- Email: [email protected]
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ultrasound performed on men with obstructive voiding symptoms and benign glands as evidenced by digital rectal palpation has little value in predicting the presence or absence of occult prostate cancer.
Editorial Comment: This interesting article demonstrates that transrectal ultrasound prior to transurethral resection of the prostate is not useful in detecting occult prostatic cancer. Patrick C. Walsh, M.D.
IMAGING Renal Cancer Staging: Comparison of Contrast-Enhanced CT and Gadolinium-Enhanced FatSuppressed Spin-Echo and Gradient-Echo MR Imaging R. C. SEMELKA, J.P. SHOENUT, C. M. MAGRO, M.A. KROEKER, R. MACMAHON AND H. M. GREENBERG, Departments of Radiology, Pathology and Surgery, St. Boniface General Hospital MRI Facility and University of Manitoba, Winnipeg, Manitoba, Canada J. Mag. Reson. Imaging, 3: 597-602, 1993 Permission fo Publish Abstract Not Granted
Editorial Comment: As expected, the quality of magnetic resonance imaging (MRI) is getting better and better, and its diagnostic ability is beginning to approach and possibly exceed that of computerized tomography (CT). This advance reflects the use of contrast material (gadolinium) and fat suppression, which is helpful in excluding the fat around the kidney and better ~etermines the presence of vascular invasion. Because of its present cost, however, MRI still is not the study of choice on a routine basis. It should be used in patients who are allergic to the usual contrast agents and those with renal failure. However, its ability to differentiate hyperplastic from malignant lymph nodes is still unclear. The authors claim that MRI showed necrosis in the involved lymph nodes, something that was not seen on CT. They also wonder whether gadolinium uptake in the lymph nodes may be of diagnostic importance but are purely speculating at this point. They claim that with pre-contrast and post-contrast scanning with 19-second breath holding techniques, lesions as small as 1 cm. can be as readily detected with MRI as with CT. Stanford M. Goldman, M.D.
First-Pass Evaluation of Renal Perfusion With TurboFLASH MR Imaging and Superparamagnetic Iron Oxide Particles H. TRILLAUD, N. GRENIER, P. DEGREZE, C. LOUAIL, C. CHAMBON AND J.-M. FRANCONI, Department of Radiology, Hopital Pellegrin Tripode and Equipe de Recherche en Imagerie Medicate, Universite de Bordeaux II, Bordeaux, Laboratoires Guerbet, Aulnay-Sous-Boix and Siemens, Division Medicate, Saint Denis, France
J. Mag. Reson. Imaging, 3: 83-91, 1993 Permission to Publish Abstract Not Granted
Editorial Comment: Presently there is no agent on the market that can evaluate perfusion on magnetic resonance imaging. The authors suggest that superparamagnetic iron oxide particles and a T2-weighted TurboFLASH (fast low-angle shot) magnetic resonance imaging sequence may be an appropriate technique to evaluate perfusion. This technique will have to be evaluated by others with regard to reliability, availability, cost and so forth. Stanford M. Goldman, M.D.
Color Flow Sonographic Mapping of Intravascular Extension of Malignant Renal Tumors
L. C. BLAKE, R. DEVERE WHITE, E. 0. GERSCOVICH AND W. E. BRANT, Departments of Radiology and Urology, University of California Davis Medical Center, Sacramento, California
J.P. McGAHAN,
J. Ultrasound Med., 12: 403-409, 1993
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The purpose of this study was to evaluate the possible role of CDFI in identifying malignant renal tumor thrombus in the renal vein or the IVC. This study involved 24 tumors in 23 patients, including 19 renal cell carcinomas, four Wilms' tumors, and one rhabdoid tumor. CDFI had an overall sensitivity of 95% in predicting combined renal vein and IVC tumor involvement but was more sensitive in the renal vein alone (100%) than in the IVC alone (89%). Specificity of CDFI was nearly equal for both renal vein and IVC thrombus at 85%. The main limitation of CDFI was its inability to predict venous tumor extension in large or bulky tumors. We would recommend CDFI as a method of detecting renal vein or IVC thrombus at the time of initial real-time sonographic detection of tumor. When CT or MR imaging is equivocal, CDFI may be used to predict tumor thrombus in the :renal vein or IVC. Editorial Comment: This interesting article reports that color flow Doppler correctly staged renal vein or inferior venal caval thrombus in 20 of 24 cases, with renal vein involvement being correctly staged in 21 and inferior vena caval involvement correctly recognized in 20. The authors had significant difficulty in staging childhood malignancy, being correct in only 2 of the 5 cases. They ascribed this result to the fact that the tumors were extremely large and compressed the inferior vena cava, making interpretation difficult. They believe that such a phenomenon would occur in adults as well. There is no question that color Doppler is an improvement over the older real-time ultrasonography, in which hyperechoic tumor thrombus may mimic a normal vein with flow. Color flow Doppler will definitely improve diagnosis but it is time-consuming. I agree with the authors that if ultrasound is performed for a possible renal mass then one should include color Doppler in the evaluation of the renal vein and inferior vena cava. I also agree that it should be used in equivocal cases on computerized tomography or magnetic resonance imaging, although proof of its efficacy in these more difficult cases is lacking in this study. It should be noted, however, that this technique will not differentiate bland clot in the inferior vena cava and renal vein from actual tumor thrombus. There have been reports of gadolinium enhancement in tumor clot on magnetic resonance imaging. Since these case reports have been incidental, there is a need for a large systematic study to prove its true efficacy in separating tumor from bland clot. Based on my experience with angiography, I believe that it will be of value in only a few cases. Stanford M. Goldman, M.D.
Hyperechoic Renal Tumors: Anechoic Rim and Intratumoral Cysts in US Differentiation of Renal Cell Carcinoma From Angiomyolipoma S. UENO, 0. MAKITA, I. OGATA, Y. HATANAKA, 0. WATANABE AND M. TAKAHASHI,Department of Radiology, Kumamoto University School of Medicine, Honjo, Kumamoto, Japan
Y. YAMASHITA,
Radiology, 188: 179-182, 1993 To determine whether angiomyolipomas (AMLs) and renal cell carcinomas (RCCs) can be differentiated at ultrasonography (US), the authors retrospectively evaluated the sonographic appearances of 31 AMLs and 38 RCCs. Sonograms were evaluated by three radiologists without knowledge of histologic findings, with respect to the echogenicity of the tumor, predominant echotexture, and whether an anechoic rim was present. All patients had also undergone computed tomography (CT) to check for tumoral fat. Intratumoral fat was evident at CT in 28 of the 31 AMLs. RCCs had no fat at CT or histologic evaluation. An anechoic rim was evident in 32 of 38 (84 % ) RCCs, and 10 RCCs had small anechoic areas with back echo enhancement, which corresponded to intratumoral cysts or cystic necrosis at histologic evaluation. The anechoic rim and areas indicative of cysts were not found in AMLs. Demonstration of an anechoic rim and/or intratumoral cysts in a hyperechoic mass at US suggests that the tumor is an RCC. Editorial Comment: Using anatopic correlation the authors claim that one can differentiate between small hyperechoic renal cell carcinomas and small hyperechoic angiomyolipomas on ultrasound based on the presence of an anechoic rim, which is seen only with renal cell carcinoma. They discuss a large series of cases to support these data. This is an important finding, which I have not observed in my own experience. I also have not encountered cases in which careful computerized tomography performed with and without contrast material using the Bosniak technique led to an inability to diagnose an angiomyolipoma. 1 However, if such a situation should arise, it might be helpful to suggest to the patient the possibility of doing a wedge resection of the small tumor rather than performing radical nephrectomy. I would be uncomfortable in just following these angiomyolipomas, in which no fat is seen on computerized tomography and which are hyperechoic without a rim on ultrasound, unless the medical condition, patient age and so forth contraindicate surgery. Stanford M. Goldman, M.D. 1. Bosniak, M. A.: Angiomyolipoma (hamartoma) of the kidney: a preoperative diagnosis is possible in virtually every case. Urol. Rad., 3: 135, 1981.
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Assessment of Inte1·1u1.i Uireteral Stent Duplex S0m.:1g1·aphy
J. F. PLATT, J. H.. Arbor, Michigan
ELLIS AND
J. M.
RUBIN,
in Patients With
Department of Radiology, University of Michigan Hospitals, Ann
AJR, HH: 87-90, 1993 OBJECTIVE. The purpose of this study was to evaluate duplex Doppler sonography in the assessment of internal ureteral stent patency. SUBJECTS AND METHODS. Thirty-three kidneys with pyelocaliectasis and an internal stent were studied with Doppler sonography and conventional sonography. Stent patency was proved by subsequent contrastenhanced studies, direct inspection of the stent after removal, or clinical follow-up. RESULTS. The 11 kidneys with stent dysfunction had a significantly higher mean resistive index (0.78 ± 0.08) than the 22 kidneys with patent stents (resistive index= 0.62 ± 0.05) (p < .001). Eighty-two percent (9/ 11) of kidneys with occluded stents had elevated resistive indexes. The two occluded stents with normal resistive indexes were found in kidneys without significant obstruction before stent placement. Ninety-one percent (20/22) of patent stents were associated with a resistive index of less than 0.70. In the two cases of falsely elevated Doppler studies, the resistive index was obtained only 24-36 hr after placement of the stent; however, the resistive index was at least 10% less than that before stent placement. No significant correlation existed between degree of pyelocaliectasis shown on real-time sonography and stent status. CONCLUSION. In the presence of pyelocaliectasis after placement of an internal ureteral stent, intrarenal Doppler sonography can be used to accurately distinguish between patency and obstruction. Real-time sonographic findings (degree of pyelocaliectasis) are not useful in this clinical situation.
Edito:rial Comment: The :resistive index obtained with Doppler studies seem§ to be a relatively accurate indicator fol" the presen.ce of obstructive pyelocaliecta!>is ver§1!ll.S :mmobst:ructive dilatation of the collecting system, This article suggests that the resistive index can also be used in patients with ureteral stents to dete:rmhi.e whether the dilatation is due to true obstruction. This finding may be important if confirmed by otheR"§. Stanford M. Goldman, MJ).
Polyme:ric Contrast Agents for MR Imaging of Adrenal Glands
R.
WEISSLEDER, Y. M. WANG, M. PAPISOV, A. BOGDANOV, B. SCHAFFER, T. J. BRADY AND J. WITTENBERG, MR Pharmaceutical Program, MGH-NMR Center, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts
J. Mag. Reson. Imaging, 3: 93-97, 1993 Permission to Publish Abstract Not Granted
Editorial Comment: The a-uthors describe a contrast agent that is specifically taken up predominantly in the cortical. zona glomen!.losa and in the medulla of the ad:renal glands. We aire an awa:1:e of the important clinical aspect§ of metaiod.obenzylguanidine in evaluation of the ad1rnnaL We are also aware of tb.e fact that many other cholesterol del'ivatives have been. developed and are in use at select institutimu, for imagh,g and diagnrn,i§ of adrenal lesions in nudea:r medicine. H i§ too early to say whetheir this '-'-"'"'"•'"'·;,; agent in fact, have a significant impact i.n better diagnosing the natu:re of adrenal lesions with :real rnr pos§ible adR·Emal disease. Stanford IVt Gold.man, M.D,
Predictive Value of Image-Guided Adrenal Biop§y: Arnalysi§ of Re§ults of 101 Biopsies
S. G. SILVERMAN, P. R. MUELLER, L. P. PINKNEY, R M. KOENKER AND S. E. SELTZER, Departments of Radiology, Brigham and Women's Hospital, and Massachusetts General Hospital, Boston, Massachusetts Radiology, 187: 715-718, 1993 A retrospective study of 97 patients undergoing 101 image-guided adrenal biopsies (IGABs) was performed to analyze the effects of specific pathologic results on test characteristics. Three categories of pathologic results (benign adrenal tissue, malignant tissue, and nondiagnostic) were compared with outcomes. Diagnostic samples were obtained in 86% of cases. Among 72 patients with proved outcomes, IGAB had an accuracy of 96%, a sensitivity of 93%, and a negative predictive value of 91 % (92% in patients with bronchogenic carcinoma). In this subset of patients, 33 had biopsy specimens that contained benign adrenal tissue. In these 33 patients, three masses (each smaller than 3 cm) proved malignant. In the 14 patients with nondiagnostic samples, two
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masses proved malignant. Obtaining benign adrenal tissue was highly predictive of benignity, even in the setting of lung cancer. The authors conclude that IGAB is an accurate procedure in both oncologic and nononcologic patients. However, when the biopsy specimen does not contain benign adrenal tissue or malignant cells, repeat percutaneous biopsy or surgery should be considered.
Editorial Comment: This article is important in that it suggests that the finding of benign adrenal tissue on a percutaneous adrenal biopsy is in most cases adequate to exclude malignancy even in the presence of a known primary tumor, such as a lung neoplasm. This is noteworthy, since it suggests that one need not have evidence of malignancy in the biopsy to be relatively comfortable with the diagnosis as long as adrenal tissue is found within the biopsy. However, the authors clearly indicate that repeat biopsies must be obtained if no true adrenal tissue is found in the specimen. In the absence of a known malignancy the authors are willing to watch the patient if the lesion is smaller than 3 cm. Other institutions use a 2 cm. cutoff. Certainly, watchful waiting for lesions smaller 2 cm. is an appropriate approach when there is no known history of malignancy or signs of a functional adrenal tumor. The authors also warn, and I agree, that biopsy will not differentiate an adrenal cortical adenoma from an adrenal cortical carcinoma, since multiple areas need to be sectioned pathologically before these lesions can be differentiated unequivocally. However, the authors are correct that it is rare to observe or diagnose a nonfunctional adrenal carcinoma that is smaller than 4 to 5 cm. However, one must remember that this fact derives from the pre-computerized tomography era, in which 2 cm. incidental adrenal tumors could not possibly be diagnosed. Stanford M. Goldman, M.D.
Evaluation of Adrenal Masses with Gadolinium Enhancement and Fat-Suppressed MR Imaging R. C. SEMELKA, J.P. SHOENUT, P.H. LAWRENCE, H. M. GREENBERG, B. MAYCHER, T. P. MADDEN AND M. A. KROEKER, Department of Radiology, St. Boniface General Hospital MRI Facility and University of Manitoba, Winnipeg, Manitoba, Canada
J. Mag. Reson. Imaging, 3: 337-343, 1993 Permission to Publish Abstract Not Granted
Editorial Comment: As expected with newer techniques and faster scanning modalities, the quality of the adrenal images on magnetic resonance imaging (MRI) is improving in tandem with the quality of the renal images. However, the cost of MRI, especially with gadolinium, hardly warrants its routine use compared to computerized tomography. MRI should be reserved for select cases in which the cost legitimizes its use, such as evaluating for pheochromocytoma when the diagnosis is equivocal on laboratory studies, or when one is interested in investigating for vascular tumor invasion. Stanford M. Goldman, M.D.
Ultrasonography and Plain Film Versus Intravenous Orography in Ureteric Colic L. D. PALMA, F. STACUL, M. BAZZOCCHI, L. PAGNAN, G. FESTINI AND D. MAREGA, Institute of Radiology, University of Trieste, and Divisions of Medicine and Urology, Cattinara Hospital Trieste, Italy Clin. Rad., 4 7: 333-336, 1993 Urography (IVU) is considered the best first investigation in patients with suspected ureteric colic, but recently ultrasonography (US), combined with a plain film of the abdomen (KUB), has been suggested as an alternative. We have undertaken a prospective study to see if this approach can be used in an Emergency Department by radiologists with different amounts of ultrasound experience. Some 180 patients with suspected ureteric colic presenting to the Emergency Department over an 8-month period were studied. They had a plain abdominal film (KUB) and US examination of the kidneys, ureters and bladder following hydration. Some 120 patients subsequently underwent IVU at a mean interval of 3.5 days after the ultrasound examination. Of these, 15 patients passed a stone before their IVU. Of the remaining 105 patients, 44 had an IVU positive for stone and 61 had a negative IVU. Fifty of the 60 patients who did not have an IVU had clinical follow-up and 31 had ultrasound. Our findings in this prospective study suggest that in the hydrated patient the combination of KUB plus US is a sensitive but not very specific screening test (sensitivity 95%, specificity 67% ). Because of the high negative predictive value of KUB plus US (95% ), urography is not likely to be helpful when KUB plus US are negative. Urography is indicated only if KUB plus US findings are equivocal or if intervention is necessary. If we had
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used KUB plus US alone as the first test in our patients, urography would have been unnecessary in approximately 60%. Twenty per cent of our patients passed a stone in the first 48 h. Editorial Comment: European radiologists have been aggressive in suggesting the use of the abdominal film plus ultrasound as an alte:rnative to u:rog:raphy. This article suggests that urog:raphy is indicated only if the abdominal film plus ultrasound are equivocal or intervention is necessary. This is particularly true as a negative predictive value, that is when the abdominal film and ultrasound are negative. In this rega:rd, Talner (reference 5 in article) believes that it takes several hou:rs for frank pyelocaliectasis to develop after sudden total obstruction. The criteria used by the authors for a positive study were the abnormal findings of stone on the abdominal film, or stone or hydronephrogis on ultrasound. The authors also claim that they detected a stone on 77% of the abdominal films. This detection rate of calculi on plain film is far higher than that seen at our institution. Most of the abdominal films we have :read have been equivocal, and the differentiation between stone and phliebolith has been nearly impossible. There is no doubt that this approach is used in Europe to a significant extent because of the ready availability of ultrasound, which is usually performed by the radiologist in the emergency :room. In the United States, however, where ultrasound examinations are not as readily available on an emergency basis, the excretory urogram will probably still be the standard technique, except in those patients with a history of allergy. Stanford M. Goldman, M.D.
Retrograde Catheterization of the Ureter Without Cystoscopic Assistance: Plt"elimina:ry Experience
S. G.
BABEL AND
K. G. WINTERKORN, X-Ray Associates of New Mexico, Albuquerque, New Mexico
Radiology, 187: 547-549, 1993 Standard angiographic techniques were applied to fluoroscopically directed retrograde guide wire or catheter placement into the distal ureter without cystoscopic assistance. The procedure was successful in five of the seven initial attempts, with no complications. Retrograde pyelography and stent placement were accomplished for a benign posttraumatic ureteral stricture, a proximal ureteral calculus, and three malignant ureteral strictures. Percutaneous nephrostomy was obviated in all successful cases. Fluoroscopy time averaged less than 3 minutes. Mild intravenous sedation was used, and the procedure was well tolerated. This initial experience suggests that this method may be useful for a variety of endourologic procedures, as well as for routine retrograde pyelography. Editorial Comment: The authors claim that their success rate with fluoroscopic retrograde ureteral cathete:rization without cystoscopy is due in part to the new guide wires that have a hydrophilic coating. This se:ries is small and one wonders whether this success rate can be rep:roduced by others in larger studies. There is no question, however', that this approach is less expensive than cystoscopic techniques. Stanford M. Goldman, M.D.
The Role of MR Imaging in Carcinoma of the U rina:ry Bl.adder J. 0. BARENTSZ, S. H.J. RUIJS ANDS. P. STRIJK, Department of Radiology, University Hospital St. Radboud, Nijmegen, The Netherlands
AJR, 160: 937-947, 1993 In this article, the role of MR imaging in the management of carcinoma of the urinary bladder is reviewed and illustrated. The appearance of the normal urinary bladder and of bladder carcinoma on MR images is shown. Important factors for optimal MR imaging of urinary bladder carcinoma are reviewed. New developments such as three-dimensional and fast spin-echo sequences and the use of contrast agents, endorectal imaging, and phased array coils are discussed. Finally, the value of MR imaging in the staging of bladder carcinoma is described, and MR staging is compared with clinical staging, staging based on findings from intravesical sonography, and CT staging.
Bladder Wall Morphology: In Vitro MR Imaging-Histopathologic Correlation Y. NARUMI, T. KADOTA, E. INOUE, K. KURIYAMA, T. HORINOUCHI, K. KASAI, H. MAEDA, M. KURODA, T. KOTAKE, S. ISHIGURO AND C. KURODA, Departments of Diagnostic Radiology, Urology and Pathology, Center for Adult Diseases, Osaka, Nakamichi, Higashinari-ku, Osaka, Japan
Radiology, 187: 151-155, 1993
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To study the morphology of the normal and inflamed bladder wall, the findings of magnetic resonance imaging and histopathologic examination of 13 in vitro specimens were correlated. Normal bladder wall appeared as a band of intermediate signal intensity on Tl-weighted images and as bands of low (inner) and intermediate (outer) signal intensity on T2-weighted images. Inflamed bladder walls demonstrated two additional inner bands of intermediate (inner) and high (innermost) signal intensity on Tl-weighted images and high (inner) and low (innermost) signal intensity on T2-weighted images. The mean histopathologic percentages of muscle bundles in inner and outer bands that appeared on T2-weighted images were 92.5% ± 4.9 and 78.3% ± 8.2, respectively. The authors conclude that the total thickness of the two bands of differing intensity that appeared on the T2-weighted images of the normal bladder wall correlated well morphometrically with the muscle layers in the histopathologic specimens, and that the different signal intensities in the muscle layer represent a compact inner and looser outer arrangement of smooth muscle bundles.
Editorial Comment: The excellent state of the art review article by Barentsz et al regarding the role of magnetic resonance imaging (MRI) in carcinoma of the bladder, and the histological correlation by N arumi et al would suggest that MRI is of value in the staging of urinary carcinoma. I do not dispute that MRI is probably better than any other currently available imaging technique in its staging ability, especially with the use of gadolinium. However, there has been a precipitous decrease in the use of MRI for bladder carcinomas at our institution and at Johns Hopkins Hospital because the information gained rarely affects clinical treatment, and the cost of computerized tomography is so much lower. However, I do believe that there are select cases in which MRI is of value. This is particularly true for bladder base lesions because one can obtain coronal and sagittal direct imaging to evaluate the status of the prostate better. In select cases we have found MRI to change the impression. from that at cystoscopy of primary bladder carcinoma to that of primary prostatic carcinoma (in l case a primary transitional cell cance:r of the prostate). Since the surgical approach is significantly altered if prostatic invasion by bladder carcinoma is present, it is incumbent that MRI be obtained in these lesions. Otherwise, computerized tomography is adequate in demonstrating lymph node involvement in most cases and in determining treatment, although MRI with gadolinium enhancement may be slightly more sensitive. Stan.ford M. Goldman, M.D.
Magnetic Resonance Imaging With Gadolinium-DTPA for Assessment of Bladder Carcinoma and Its Response to Treatment
J.M. HAWNAUR, R. J. JOHNSON, G. READ AND I. ISHERWOOD, Department of Diagnostic Radiology, University of Manchester and Department of Radiotherapy, Christie Hospital and Holt Radium Institute, Manchester, England Clin. Rad., 47: 302-310, 1993 Magnetic Resonance Imaging (MRI) with intravenous Gadolinium-DTP A (Gd-DTP A, Magnevist, ScheringAG) was performed in 44 patients, 32 with primary bladder carcinoma and 12 with suspected recurrence after treatment. Gd-DTPA often increased diagnostic confidence in the identification and staging of tumours confined to the bladder wall and was necessary to assess depth of bladder wall invasion when T2-weighted images were suboptimal. Enhancement after Gd-DTP A enabled distinction between necrotic and viable tumour and blood clot. There was little advantage in its use for tumours infiltrating perivesical fat or with metastases to lymph nodes or bone, in the absence of a fat suppression sequence. Gd-DTPA may therefore be useful in selected patients with tumours of Stage T3a or less in whom information about depth of bladder wall invasion is inadequately shown on pre-contrast sequences. Artefacts due to variable and inhomogeneous urine signal intensity, however, often degraded post-Gd-DTPA images of the bladder. Changes in the bladder due to radiotherapy were observed on MRI 3-4 months after treatment in patients referred for routine follow-up and in some patients with suspected recurrence. Mucosal hyperintensity, thickening and abnormal signal intensity of the muscular layers of the bladder wall, with enhancement after Gd-DTP A were demonstrated. Such changes obscured small volume or superficial recurrence of tumour after radiotherapy. Abnormal enhancement was also observed in pelvic organs and soft tissues irradiated several years earlier. Enhancement after Gd-DTPA does not therefore reliably distinguish between recurrent tumour and radiotherapy change. Editorial Comment: My opinion regarding the value of MRI in the preoperative diagnosis of bladder carcinoma has been stated in the preceding comment. This article confirms what one would have suspected, that is gadolinium-enhanced studies cannot differentiate between radiation-induced inflammatory changes and recurrent post-radiation. tumor in patients with known bladder cancer. Stanford M. Goldman, M.D.
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T:ransureiiual Balloon Dilation of the Extei·nal Urinary SphincteK': Effectiveness in Spinal Co:rdInjured Men With Detrusor-External Uretlural Sphincter Dyssynergia M. B. CHANCELLOR, S. KARASICK, S. STRUP, C. K. ABDILL, L H. HIRSCH AND W. E. STAAS, Departments of Urology and Radiology, Jefferson Medical College and Thomas Jefferson University, and Magee Rehabilitation Hospital, Philadelphia, Pennsylvania
Radiology, 187: 557-560, 1993 Abstract Printed in J. Urol., 150: 2035, 1993
Placement of a Wire Mesh Prosthesis in the External Urinary Sphincter of Men With Spinal Co:rd In.juries
M. B.
CHANCELLOR, S. KARUSICK, M. J. ERHARD, C. K. ABDILL, J.-B. Lrn, STAAS, Departments of Urology and Radiology, Jefferson Medical College and
B. B. GOLDBERG AND W. E. Thomas Jefferson University,
and Magee Rehabilitation Hospital, Philadelphia, Pennsylvania Radiology, 187: 551-555, 1993 Abstract Printed in J. Urol., 150: 2035, 1993 Editorial Comment: Interestingly, these 2 studies are reported in the radiological literature, although the senior author is a urologist. Each a:rticle deals with a different method of managing external urethral sphincter dyssynergia in patients with spinal cord injury. Based on these reports, both techniques seem to have merit and deserve further evaluation, especially with regard to longterm :results. More long-term studies are necessary to determine which method is the most effective, although the authors report improved fertility in 3 patients treated with the balloon technique. We have no experience with either of these procedures, although apparently there has been some evaluation of balloon dilation in Europe with somewhat poorer results. Stanfo:rd M. Goldman, M.D.
Impact of Contrast Medium Temperature on Bladder Capacity and Cystogiraphic Diagnosis of Vesicoureteral Reflux in Chi.ldre:n J.M. ZERIN, Section of Pediatric Radiology, Department of Radiology, C. S. Mott Children's Hospital, University of Michigan Hospitals, Ann Arbor, Michigan
Radiology, 187: 161-164, 1993 To assess the influence of temperature of contrast medium used in voiding cystourethrography (VCUG) on the estimation of bladder capacity and detection of vesicoureteral reflux (VUR), 250 consecutive children (aged from birth to 13.5 years) undergoing VCUG were randomized to receive room temperature (n = 133) or body temperature (n = 117) contrast medium. Bladder capacity (ie, volume infused) was measured, and bladder volume index (BVI) was calculated by dividing the measured capacity by the predicted capacity. Contrast medium temperature did not affect either bladder capacity (warm: mean capacity, 210.8 mL; cold: mean capacity, 212.6 mL) or BVI (warm: mean BVI, 1.15; cold: mean BVI, 1.10). Although boys had smaller capacities than girls, neither capacity nor BVI was significantly (P > .05) affected by contrast medium temperature in either sex. VUR was detected in 42 (35.9%) of 117 children studied with warmed contrast medium and in 42 (31.6%) of 133 studied with room temperature medium. Prevalence of VUR was unaffected by contrast medium temperature in children with previously diagnosed VUR and in those studied for the first time. Editorial. Comment: This §imple study shows that temperature does not affect blad.deF volume or the ability to demonstrate reflux. The simplicity of the study makes it noteworthy to the casual observer as an example of simple but effective clinical research. Stanford M. Goldman, M.D.
Incidental Vesicoureteral Reflux in Neonates With An.tenatally Detected Hydronephrosis and Other Renal Abnormalities J. M. ZERIN, M. L. RITCHEY AND A. C. H. CHANG, Section of Pediatric Radiology, Department of Radiology and Section of Pediatric Urology, Department of Surgery, C. S. Mott Children's Hospital, University of Michigan Hospitals, Ann Arbor, Michigan Radiology, 187: 157-160, 1993 Abstract Printed in J. Urol., 150: 1336-1337, 1993
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Neonatal Vesicoureteral Reflux: What Do We Know? R. L. LEBOWITZ, Division of Diagnostic Radiology, Department of Radiology, Harvard Medical School and Children's Hospital, Boston, Massachusetts Radiology, 187: 17, 1993 No Abstract
Editorial Comment: I strongly recommend this article and the somewhat controversial accompanying editorial, which makes the following points. 1) The study demonstrates the usefulness of a computerized data base in clinical research in that it enables one to correlate the imaging information as it affects the care of the patient. 2) The authors show that when hydronephrosis is detected in utero, reflux is the single most common cause. It is so common, according to Lebowitz, that he strongly recommends that all infants with prenatally detected hydronephrosis be given antibiotic prophylaxis until a voiding cystourethrogram can be performed. Breast-feeding and circumcision should also be encouraged in these cases. 3) The report also demonstrates that the background prevalence of reflux is low. In fact, the frequency of reflux in a subset studied was equal regardless of gender, although in boys the incidence of urinary infection was more common and the severity of reflux was higher. Lebowitz recommends that a child with a urinary tract infection be evaluated immediately. 4) The report confirms the International Reflux Study Group findings that if the reflux resolves spontaneously it does so at a much younger age than previously believed. 5) Ultrasound is a poor screening technique for reflux in the neonate. In fact, 25% of the patients with hydronephrosis on prenatal ultrasound had a normal postnatal ultrasound but had reflux on voiding cystourethrography. Lebowitz raises philosophical questions to which there are no answers. By finding patients who are not sick prenatally, are we treating and studying too many patients? I believe that we are not. He also wonders whether several of the children with a normal ultrasound prenatally may, in fact, have reflux. Hopefully, few of these cases will remain undetected before damage to the kidneys occurs. Stanford M. Goldman, M.D.
PEDIATRIC UROLOGY Treatment.of Vesicoureteric Reflux: Results of a Prospective Study R. J. SCHOLTMEIJER, Department of Paediatric Urology, Sophia Children's Hospital, Erasmus University, Rotterdam, The Netherlands Brit. J. Urol., 71: 346-349, 1993 Between 1982 and 1986, 96 children with non-obstructive vesicoureteric reflux were included in a prospective ~tudy. Three patients withdrew from the study and results are therefore presented on 93 children with 135 J/~flµjing ureters who were followed up for at least 5 years. Initially, all children with reflux grade III or less received antibiotic treatment only. Those with reflux grade IV were randomised to antibiotic treatment alone versus surgery plus antibiotic treatment; the primary treatment of reflux grade V was reimplantation. In 85 ureters treated by antibiotics only, reflux disappeared in 64 cases and was reduced in 12. In 50 ureters treated by reimplantation, reflux was cured in 46 cases and no severe ureteric obstruction was seen. Conservative management of reflux grade IV was less successful than surgery. The results of conservative, non-surgical treatment of reflux grades 1-111 were satisfactory, but for grades IV and V surgery should be the treatment of choice if detrusor instability has been excluded.
Editorial Comment: This study reports the late followup of 93 children with 135 refluxing ureters. At 5 years 6 of 11 ureters (55%) with grade 4 reflux showed resolution and 3 demonstrated reduction in grade. However, 7 additional patients with grade 4 reflux initially assigned to medical therapy were crossed over to reimplantation because of breakthrough urinary tract infection or increased reflux. Of the 36 ureters with grade 3 reflux 21 (58%) had resolution at 5 years, 7 (19%) had reduction in reflux grade and 8 (22%) were crossed over to reimplantation because of increasing reflux or breakthrough urinary tract infection. Overall 23 of 105 ureters were subjected to reimplantation because of breakthrough urinary tract infection and/or increasing reflux grade.
ultrasound performed on men with obstructive voiding symptoms and benign glands as evidenced by digital rectal palpation has little value in predicting the presence or absence of occult prostate cancer.
Editorial Comment: This interesting article demonstrates that transrectal ultrasound prior to transurethral resection of the prostate is not useful in detecting occult prostatic cancer. Patrick C. Walsh, M.D.
IMAGING Renal Cancer Staging: Comparison of Contrast-Enhanced CT and Gadolinium-Enhanced FatSuppressed Spin-Echo and Gradient-Echo MR Imaging R. C. SEMELKA, J.P. SHOENUT, C. M. MAGRO, M.A. KROEKER, R. MACMAHON AND H. M. GREENBERG, Departments of Radiology, Pathology and Surgery, St. Boniface General Hospital MRI Facility and University of Manitoba, Winnipeg, Manitoba, Canada J. Mag. Reson. Imaging, 3: 597-602, 1993 Permission fo Publish Abstract Not Granted
Editorial Comment: As expected, the quality of magnetic resonance imaging (MRI) is getting better and better, and its diagnostic ability is beginning to approach and possibly exceed that of computerized tomography (CT). This advance reflects the use of contrast material (gadolinium) and fat suppression, which is helpful in excluding the fat around the kidney and better ~etermines the presence of vascular invasion. Because of its present cost, however, MRI still is not the study of choice on a routine basis. It should be used in patients who are allergic to the usual contrast agents and those with renal failure. However, its ability to differentiate hyperplastic from malignant lymph nodes is still unclear. The authors claim that MRI showed necrosis in the involved lymph nodes, something that was not seen on CT. They also wonder whether gadolinium uptake in the lymph nodes may be of diagnostic importance but are purely speculating at this point. They claim that with pre-contrast and post-contrast scanning with 19-second breath holding techniques, lesions as small as 1 cm. can be as readily detected with MRI as with CT. Stanford M. Goldman, M.D.
First-Pass Evaluation of Renal Perfusion With TurboFLASH MR Imaging and Superparamagnetic Iron Oxide Particles H. TRILLAUD, N. GRENIER, P. DEGREZE, C. LOUAIL, C. CHAMBON AND J.-M. FRANCONI, Department of Radiology, Hopital Pellegrin Tripode and Equipe de Recherche en Imagerie Medicate, Universite de Bordeaux II, Bordeaux, Laboratoires Guerbet, Aulnay-Sous-Boix and Siemens, Division Medicate, Saint Denis, France
J. Mag. Reson. Imaging, 3: 83-91, 1993 Permission to Publish Abstract Not Granted
Editorial Comment: Presently there is no agent on the market that can evaluate perfusion on magnetic resonance imaging. The authors suggest that superparamagnetic iron oxide particles and a T2-weighted TurboFLASH (fast low-angle shot) magnetic resonance imaging sequence may be an appropriate technique to evaluate perfusion. This technique will have to be evaluated by others with regard to reliability, availability, cost and so forth. Stanford M. Goldman, M.D.
Color Flow Sonographic Mapping of Intravascular Extension of Malignant Renal Tumors
L. C. BLAKE, R. DEVERE WHITE, E. 0. GERSCOVICH AND W. E. BRANT, Departments of Radiology and Urology, University of California Davis Medical Center, Sacramento, California
J.P. McGAHAN,
J. Ultrasound Med., 12: 403-409, 1993
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The purpose of this study was to evaluate the possible role of CDFI in identifying malignant renal tumor thrombus in the renal vein or the IVC. This study involved 24 tumors in 23 patients, including 19 renal cell carcinomas, four Wilms' tumors, and one rhabdoid tumor. CDFI had an overall sensitivity of 95% in predicting combined renal vein and IVC tumor involvement but was more sensitive in the renal vein alone (100%) than in the IVC alone (89%). Specificity of CDFI was nearly equal for both renal vein and IVC thrombus at 85%. The main limitation of CDFI was its inability to predict venous tumor extension in large or bulky tumors. We would recommend CDFI as a method of detecting renal vein or IVC thrombus at the time of initial real-time sonographic detection of tumor. When CT or MR imaging is equivocal, CDFI may be used to predict tumor thrombus in the :renal vein or IVC. Editorial Comment: This interesting article reports that color flow Doppler correctly staged renal vein or inferior venal caval thrombus in 20 of 24 cases, with renal vein involvement being correctly staged in 21 and inferior vena caval involvement correctly recognized in 20. The authors had significant difficulty in staging childhood malignancy, being correct in only 2 of the 5 cases. They ascribed this result to the fact that the tumors were extremely large and compressed the inferior vena cava, making interpretation difficult. They believe that such a phenomenon would occur in adults as well. There is no question that color Doppler is an improvement over the older real-time ultrasonography, in which hyperechoic tumor thrombus may mimic a normal vein with flow. Color flow Doppler will definitely improve diagnosis but it is time-consuming. I agree with the authors that if ultrasound is performed for a possible renal mass then one should include color Doppler in the evaluation of the renal vein and inferior vena cava. I also agree that it should be used in equivocal cases on computerized tomography or magnetic resonance imaging, although proof of its efficacy in these more difficult cases is lacking in this study. It should be noted, however, that this technique will not differentiate bland clot in the inferior vena cava and renal vein from actual tumor thrombus. There have been reports of gadolinium enhancement in tumor clot on magnetic resonance imaging. Since these case reports have been incidental, there is a need for a large systematic study to prove its true efficacy in separating tumor from bland clot. Based on my experience with angiography, I believe that it will be of value in only a few cases. Stanford M. Goldman, M.D.
Hyperechoic Renal Tumors: Anechoic Rim and Intratumoral Cysts in US Differentiation of Renal Cell Carcinoma From Angiomyolipoma S. UENO, 0. MAKITA, I. OGATA, Y. HATANAKA, 0. WATANABE AND M. TAKAHASHI,Department of Radiology, Kumamoto University School of Medicine, Honjo, Kumamoto, Japan
Y. YAMASHITA,
Radiology, 188: 179-182, 1993 To determine whether angiomyolipomas (AMLs) and renal cell carcinomas (RCCs) can be differentiated at ultrasonography (US), the authors retrospectively evaluated the sonographic appearances of 31 AMLs and 38 RCCs. Sonograms were evaluated by three radiologists without knowledge of histologic findings, with respect to the echogenicity of the tumor, predominant echotexture, and whether an anechoic rim was present. All patients had also undergone computed tomography (CT) to check for tumoral fat. Intratumoral fat was evident at CT in 28 of the 31 AMLs. RCCs had no fat at CT or histologic evaluation. An anechoic rim was evident in 32 of 38 (84 % ) RCCs, and 10 RCCs had small anechoic areas with back echo enhancement, which corresponded to intratumoral cysts or cystic necrosis at histologic evaluation. The anechoic rim and areas indicative of cysts were not found in AMLs. Demonstration of an anechoic rim and/or intratumoral cysts in a hyperechoic mass at US suggests that the tumor is an RCC. Editorial Comment: Using anatopic correlation the authors claim that one can differentiate between small hyperechoic renal cell carcinomas and small hyperechoic angiomyolipomas on ultrasound based on the presence of an anechoic rim, which is seen only with renal cell carcinoma. They discuss a large series of cases to support these data. This is an important finding, which I have not observed in my own experience. I also have not encountered cases in which careful computerized tomography performed with and without contrast material using the Bosniak technique led to an inability to diagnose an angiomyolipoma. 1 However, if such a situation should arise, it might be helpful to suggest to the patient the possibility of doing a wedge resection of the small tumor rather than performing radical nephrectomy. I would be uncomfortable in just following these angiomyolipomas, in which no fat is seen on computerized tomography and which are hyperechoic without a rim on ultrasound, unless the medical condition, patient age and so forth contraindicate surgery. Stanford M. Goldman, M.D. 1. Bosniak, M. A.: Angiomyolipoma (hamartoma) of the kidney: a preoperative diagnosis is possible in virtually every case. Urol. Rad., 3: 135, 1981.
287
Assessment of Inte1·1u1.i Uireteral Stent Duplex S0m.:1g1·aphy
J. F. PLATT, J. H.. Arbor, Michigan
ELLIS AND
J. M.
RUBIN,
in Patients With
Department of Radiology, University of Michigan Hospitals, Ann
AJR, HH: 87-90, 1993 OBJECTIVE. The purpose of this study was to evaluate duplex Doppler sonography in the assessment of internal ureteral stent patency. SUBJECTS AND METHODS. Thirty-three kidneys with pyelocaliectasis and an internal stent were studied with Doppler sonography and conventional sonography. Stent patency was proved by subsequent contrastenhanced studies, direct inspection of the stent after removal, or clinical follow-up. RESULTS. The 11 kidneys with stent dysfunction had a significantly higher mean resistive index (0.78 ± 0.08) than the 22 kidneys with patent stents (resistive index= 0.62 ± 0.05) (p < .001). Eighty-two percent (9/ 11) of kidneys with occluded stents had elevated resistive indexes. The two occluded stents with normal resistive indexes were found in kidneys without significant obstruction before stent placement. Ninety-one percent (20/22) of patent stents were associated with a resistive index of less than 0.70. In the two cases of falsely elevated Doppler studies, the resistive index was obtained only 24-36 hr after placement of the stent; however, the resistive index was at least 10% less than that before stent placement. No significant correlation existed between degree of pyelocaliectasis shown on real-time sonography and stent status. CONCLUSION. In the presence of pyelocaliectasis after placement of an internal ureteral stent, intrarenal Doppler sonography can be used to accurately distinguish between patency and obstruction. Real-time sonographic findings (degree of pyelocaliectasis) are not useful in this clinical situation.
Edito:rial Comment: The :resistive index obtained with Doppler studies seem§ to be a relatively accurate indicator fol" the presen.ce of obstructive pyelocaliecta!>is ver§1!ll.S :mmobst:ructive dilatation of the collecting system, This article suggests that the resistive index can also be used in patients with ureteral stents to dete:rmhi.e whether the dilatation is due to true obstruction. This finding may be important if confirmed by otheR"§. Stanford M. Goldman, MJ).
Polyme:ric Contrast Agents for MR Imaging of Adrenal Glands
R.
WEISSLEDER, Y. M. WANG, M. PAPISOV, A. BOGDANOV, B. SCHAFFER, T. J. BRADY AND J. WITTENBERG, MR Pharmaceutical Program, MGH-NMR Center, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts
J. Mag. Reson. Imaging, 3: 93-97, 1993 Permission to Publish Abstract Not Granted
Editorial Comment: The a-uthors describe a contrast agent that is specifically taken up predominantly in the cortical. zona glomen!.losa and in the medulla of the ad:renal glands. We aire an awa:1:e of the important clinical aspect§ of metaiod.obenzylguanidine in evaluation of the ad1rnnaL We are also aware of tb.e fact that many other cholesterol del'ivatives have been. developed and are in use at select institutimu, for imagh,g and diagnrn,i§ of adrenal lesions in nudea:r medicine. H i§ too early to say whetheir this '-'-"'"'"•'"'·;,; agent in fact, have a significant impact i.n better diagnosing the natu:re of adrenal lesions with :real rnr pos§ible adR·Emal disease. Stanford IVt Gold.man, M.D,
Predictive Value of Image-Guided Adrenal Biop§y: Arnalysi§ of Re§ults of 101 Biopsies
S. G. SILVERMAN, P. R. MUELLER, L. P. PINKNEY, R M. KOENKER AND S. E. SELTZER, Departments of Radiology, Brigham and Women's Hospital, and Massachusetts General Hospital, Boston, Massachusetts Radiology, 187: 715-718, 1993 A retrospective study of 97 patients undergoing 101 image-guided adrenal biopsies (IGABs) was performed to analyze the effects of specific pathologic results on test characteristics. Three categories of pathologic results (benign adrenal tissue, malignant tissue, and nondiagnostic) were compared with outcomes. Diagnostic samples were obtained in 86% of cases. Among 72 patients with proved outcomes, IGAB had an accuracy of 96%, a sensitivity of 93%, and a negative predictive value of 91 % (92% in patients with bronchogenic carcinoma). In this subset of patients, 33 had biopsy specimens that contained benign adrenal tissue. In these 33 patients, three masses (each smaller than 3 cm) proved malignant. In the 14 patients with nondiagnostic samples, two
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masses proved malignant. Obtaining benign adrenal tissue was highly predictive of benignity, even in the setting of lung cancer. The authors conclude that IGAB is an accurate procedure in both oncologic and nononcologic patients. However, when the biopsy specimen does not contain benign adrenal tissue or malignant cells, repeat percutaneous biopsy or surgery should be considered.
Editorial Comment: This article is important in that it suggests that the finding of benign adrenal tissue on a percutaneous adrenal biopsy is in most cases adequate to exclude malignancy even in the presence of a known primary tumor, such as a lung neoplasm. This is noteworthy, since it suggests that one need not have evidence of malignancy in the biopsy to be relatively comfortable with the diagnosis as long as adrenal tissue is found within the biopsy. However, the authors clearly indicate that repeat biopsies must be obtained if no true adrenal tissue is found in the specimen. In the absence of a known malignancy the authors are willing to watch the patient if the lesion is smaller than 3 cm. Other institutions use a 2 cm. cutoff. Certainly, watchful waiting for lesions smaller 2 cm. is an appropriate approach when there is no known history of malignancy or signs of a functional adrenal tumor. The authors also warn, and I agree, that biopsy will not differentiate an adrenal cortical adenoma from an adrenal cortical carcinoma, since multiple areas need to be sectioned pathologically before these lesions can be differentiated unequivocally. However, the authors are correct that it is rare to observe or diagnose a nonfunctional adrenal carcinoma that is smaller than 4 to 5 cm. However, one must remember that this fact derives from the pre-computerized tomography era, in which 2 cm. incidental adrenal tumors could not possibly be diagnosed. Stanford M. Goldman, M.D.
Evaluation of Adrenal Masses with Gadolinium Enhancement and Fat-Suppressed MR Imaging R. C. SEMELKA, J.P. SHOENUT, P.H. LAWRENCE, H. M. GREENBERG, B. MAYCHER, T. P. MADDEN AND M. A. KROEKER, Department of Radiology, St. Boniface General Hospital MRI Facility and University of Manitoba, Winnipeg, Manitoba, Canada
J. Mag. Reson. Imaging, 3: 337-343, 1993 Permission to Publish Abstract Not Granted
Editorial Comment: As expected with newer techniques and faster scanning modalities, the quality of the adrenal images on magnetic resonance imaging (MRI) is improving in tandem with the quality of the renal images. However, the cost of MRI, especially with gadolinium, hardly warrants its routine use compared to computerized tomography. MRI should be reserved for select cases in which the cost legitimizes its use, such as evaluating for pheochromocytoma when the diagnosis is equivocal on laboratory studies, or when one is interested in investigating for vascular tumor invasion. Stanford M. Goldman, M.D.
Ultrasonography and Plain Film Versus Intravenous Orography in Ureteric Colic L. D. PALMA, F. STACUL, M. BAZZOCCHI, L. PAGNAN, G. FESTINI AND D. MAREGA, Institute of Radiology, University of Trieste, and Divisions of Medicine and Urology, Cattinara Hospital Trieste, Italy Clin. Rad., 4 7: 333-336, 1993 Urography (IVU) is considered the best first investigation in patients with suspected ureteric colic, but recently ultrasonography (US), combined with a plain film of the abdomen (KUB), has been suggested as an alternative. We have undertaken a prospective study to see if this approach can be used in an Emergency Department by radiologists with different amounts of ultrasound experience. Some 180 patients with suspected ureteric colic presenting to the Emergency Department over an 8-month period were studied. They had a plain abdominal film (KUB) and US examination of the kidneys, ureters and bladder following hydration. Some 120 patients subsequently underwent IVU at a mean interval of 3.5 days after the ultrasound examination. Of these, 15 patients passed a stone before their IVU. Of the remaining 105 patients, 44 had an IVU positive for stone and 61 had a negative IVU. Fifty of the 60 patients who did not have an IVU had clinical follow-up and 31 had ultrasound. Our findings in this prospective study suggest that in the hydrated patient the combination of KUB plus US is a sensitive but not very specific screening test (sensitivity 95%, specificity 67% ). Because of the high negative predictive value of KUB plus US (95% ), urography is not likely to be helpful when KUB plus US are negative. Urography is indicated only if KUB plus US findings are equivocal or if intervention is necessary. If we had
Ii'JAG!:NG
used KUB plus US alone as the first test in our patients, urography would have been unnecessary in approximately 60%. Twenty per cent of our patients passed a stone in the first 48 h. Editorial Comment: European radiologists have been aggressive in suggesting the use of the abdominal film plus ultrasound as an alte:rnative to u:rog:raphy. This article suggests that urog:raphy is indicated only if the abdominal film plus ultrasound are equivocal or intervention is necessary. This is particularly true as a negative predictive value, that is when the abdominal film and ultrasound are negative. In this rega:rd, Talner (reference 5 in article) believes that it takes several hou:rs for frank pyelocaliectasis to develop after sudden total obstruction. The criteria used by the authors for a positive study were the abnormal findings of stone on the abdominal film, or stone or hydronephrogis on ultrasound. The authors also claim that they detected a stone on 77% of the abdominal films. This detection rate of calculi on plain film is far higher than that seen at our institution. Most of the abdominal films we have :read have been equivocal, and the differentiation between stone and phliebolith has been nearly impossible. There is no doubt that this approach is used in Europe to a significant extent because of the ready availability of ultrasound, which is usually performed by the radiologist in the emergency :room. In the United States, however, where ultrasound examinations are not as readily available on an emergency basis, the excretory urogram will probably still be the standard technique, except in those patients with a history of allergy. Stanford M. Goldman, M.D.
Retrograde Catheterization of the Ureter Without Cystoscopic Assistance: Plt"elimina:ry Experience
S. G.
BABEL AND
K. G. WINTERKORN, X-Ray Associates of New Mexico, Albuquerque, New Mexico
Radiology, 187: 547-549, 1993 Standard angiographic techniques were applied to fluoroscopically directed retrograde guide wire or catheter placement into the distal ureter without cystoscopic assistance. The procedure was successful in five of the seven initial attempts, with no complications. Retrograde pyelography and stent placement were accomplished for a benign posttraumatic ureteral stricture, a proximal ureteral calculus, and three malignant ureteral strictures. Percutaneous nephrostomy was obviated in all successful cases. Fluoroscopy time averaged less than 3 minutes. Mild intravenous sedation was used, and the procedure was well tolerated. This initial experience suggests that this method may be useful for a variety of endourologic procedures, as well as for routine retrograde pyelography. Editorial Comment: The authors claim that their success rate with fluoroscopic retrograde ureteral cathete:rization without cystoscopy is due in part to the new guide wires that have a hydrophilic coating. This se:ries is small and one wonders whether this success rate can be rep:roduced by others in larger studies. There is no question, however', that this approach is less expensive than cystoscopic techniques. Stanford M. Goldman, M.D.
The Role of MR Imaging in Carcinoma of the U rina:ry Bl.adder J. 0. BARENTSZ, S. H.J. RUIJS ANDS. P. STRIJK, Department of Radiology, University Hospital St. Radboud, Nijmegen, The Netherlands
AJR, 160: 937-947, 1993 In this article, the role of MR imaging in the management of carcinoma of the urinary bladder is reviewed and illustrated. The appearance of the normal urinary bladder and of bladder carcinoma on MR images is shown. Important factors for optimal MR imaging of urinary bladder carcinoma are reviewed. New developments such as three-dimensional and fast spin-echo sequences and the use of contrast agents, endorectal imaging, and phased array coils are discussed. Finally, the value of MR imaging in the staging of bladder carcinoma is described, and MR staging is compared with clinical staging, staging based on findings from intravesical sonography, and CT staging.
Bladder Wall Morphology: In Vitro MR Imaging-Histopathologic Correlation Y. NARUMI, T. KADOTA, E. INOUE, K. KURIYAMA, T. HORINOUCHI, K. KASAI, H. MAEDA, M. KURODA, T. KOTAKE, S. ISHIGURO AND C. KURODA, Departments of Diagnostic Radiology, Urology and Pathology, Center for Adult Diseases, Osaka, Nakamichi, Higashinari-ku, Osaka, Japan
Radiology, 187: 151-155, 1993
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To study the morphology of the normal and inflamed bladder wall, the findings of magnetic resonance imaging and histopathologic examination of 13 in vitro specimens were correlated. Normal bladder wall appeared as a band of intermediate signal intensity on Tl-weighted images and as bands of low (inner) and intermediate (outer) signal intensity on T2-weighted images. Inflamed bladder walls demonstrated two additional inner bands of intermediate (inner) and high (innermost) signal intensity on Tl-weighted images and high (inner) and low (innermost) signal intensity on T2-weighted images. The mean histopathologic percentages of muscle bundles in inner and outer bands that appeared on T2-weighted images were 92.5% ± 4.9 and 78.3% ± 8.2, respectively. The authors conclude that the total thickness of the two bands of differing intensity that appeared on the T2-weighted images of the normal bladder wall correlated well morphometrically with the muscle layers in the histopathologic specimens, and that the different signal intensities in the muscle layer represent a compact inner and looser outer arrangement of smooth muscle bundles.
Editorial Comment: The excellent state of the art review article by Barentsz et al regarding the role of magnetic resonance imaging (MRI) in carcinoma of the bladder, and the histological correlation by N arumi et al would suggest that MRI is of value in the staging of urinary carcinoma. I do not dispute that MRI is probably better than any other currently available imaging technique in its staging ability, especially with the use of gadolinium. However, there has been a precipitous decrease in the use of MRI for bladder carcinomas at our institution and at Johns Hopkins Hospital because the information gained rarely affects clinical treatment, and the cost of computerized tomography is so much lower. However, I do believe that there are select cases in which MRI is of value. This is particularly true for bladder base lesions because one can obtain coronal and sagittal direct imaging to evaluate the status of the prostate better. In select cases we have found MRI to change the impression. from that at cystoscopy of primary bladder carcinoma to that of primary prostatic carcinoma (in l case a primary transitional cell cance:r of the prostate). Since the surgical approach is significantly altered if prostatic invasion by bladder carcinoma is present, it is incumbent that MRI be obtained in these lesions. Otherwise, computerized tomography is adequate in demonstrating lymph node involvement in most cases and in determining treatment, although MRI with gadolinium enhancement may be slightly more sensitive. Stan.ford M. Goldman, M.D.
Magnetic Resonance Imaging With Gadolinium-DTPA for Assessment of Bladder Carcinoma and Its Response to Treatment
J.M. HAWNAUR, R. J. JOHNSON, G. READ AND I. ISHERWOOD, Department of Diagnostic Radiology, University of Manchester and Department of Radiotherapy, Christie Hospital and Holt Radium Institute, Manchester, England Clin. Rad., 47: 302-310, 1993 Magnetic Resonance Imaging (MRI) with intravenous Gadolinium-DTP A (Gd-DTP A, Magnevist, ScheringAG) was performed in 44 patients, 32 with primary bladder carcinoma and 12 with suspected recurrence after treatment. Gd-DTPA often increased diagnostic confidence in the identification and staging of tumours confined to the bladder wall and was necessary to assess depth of bladder wall invasion when T2-weighted images were suboptimal. Enhancement after Gd-DTP A enabled distinction between necrotic and viable tumour and blood clot. There was little advantage in its use for tumours infiltrating perivesical fat or with metastases to lymph nodes or bone, in the absence of a fat suppression sequence. Gd-DTPA may therefore be useful in selected patients with tumours of Stage T3a or less in whom information about depth of bladder wall invasion is inadequately shown on pre-contrast sequences. Artefacts due to variable and inhomogeneous urine signal intensity, however, often degraded post-Gd-DTPA images of the bladder. Changes in the bladder due to radiotherapy were observed on MRI 3-4 months after treatment in patients referred for routine follow-up and in some patients with suspected recurrence. Mucosal hyperintensity, thickening and abnormal signal intensity of the muscular layers of the bladder wall, with enhancement after Gd-DTP A were demonstrated. Such changes obscured small volume or superficial recurrence of tumour after radiotherapy. Abnormal enhancement was also observed in pelvic organs and soft tissues irradiated several years earlier. Enhancement after Gd-DTPA does not therefore reliably distinguish between recurrent tumour and radiotherapy change. Editorial Comment: My opinion regarding the value of MRI in the preoperative diagnosis of bladder carcinoma has been stated in the preceding comment. This article confirms what one would have suspected, that is gadolinium-enhanced studies cannot differentiate between radiation-induced inflammatory changes and recurrent post-radiation. tumor in patients with known bladder cancer. Stanford M. Goldman, M.D.
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T:ransureiiual Balloon Dilation of the Extei·nal Urinary SphincteK': Effectiveness in Spinal Co:rdInjured Men With Detrusor-External Uretlural Sphincter Dyssynergia M. B. CHANCELLOR, S. KARASICK, S. STRUP, C. K. ABDILL, L H. HIRSCH AND W. E. STAAS, Departments of Urology and Radiology, Jefferson Medical College and Thomas Jefferson University, and Magee Rehabilitation Hospital, Philadelphia, Pennsylvania
Radiology, 187: 557-560, 1993 Abstract Printed in J. Urol., 150: 2035, 1993
Placement of a Wire Mesh Prosthesis in the External Urinary Sphincter of Men With Spinal Co:rd In.juries
M. B.
CHANCELLOR, S. KARUSICK, M. J. ERHARD, C. K. ABDILL, J.-B. Lrn, STAAS, Departments of Urology and Radiology, Jefferson Medical College and
B. B. GOLDBERG AND W. E. Thomas Jefferson University,
and Magee Rehabilitation Hospital, Philadelphia, Pennsylvania Radiology, 187: 551-555, 1993 Abstract Printed in J. Urol., 150: 2035, 1993 Editorial Comment: Interestingly, these 2 studies are reported in the radiological literature, although the senior author is a urologist. Each a:rticle deals with a different method of managing external urethral sphincter dyssynergia in patients with spinal cord injury. Based on these reports, both techniques seem to have merit and deserve further evaluation, especially with regard to longterm :results. More long-term studies are necessary to determine which method is the most effective, although the authors report improved fertility in 3 patients treated with the balloon technique. We have no experience with either of these procedures, although apparently there has been some evaluation of balloon dilation in Europe with somewhat poorer results. Stanfo:rd M. Goldman, M.D.
Impact of Contrast Medium Temperature on Bladder Capacity and Cystogiraphic Diagnosis of Vesicoureteral Reflux in Chi.ldre:n J.M. ZERIN, Section of Pediatric Radiology, Department of Radiology, C. S. Mott Children's Hospital, University of Michigan Hospitals, Ann Arbor, Michigan
Radiology, 187: 161-164, 1993 To assess the influence of temperature of contrast medium used in voiding cystourethrography (VCUG) on the estimation of bladder capacity and detection of vesicoureteral reflux (VUR), 250 consecutive children (aged from birth to 13.5 years) undergoing VCUG were randomized to receive room temperature (n = 133) or body temperature (n = 117) contrast medium. Bladder capacity (ie, volume infused) was measured, and bladder volume index (BVI) was calculated by dividing the measured capacity by the predicted capacity. Contrast medium temperature did not affect either bladder capacity (warm: mean capacity, 210.8 mL; cold: mean capacity, 212.6 mL) or BVI (warm: mean BVI, 1.15; cold: mean BVI, 1.10). Although boys had smaller capacities than girls, neither capacity nor BVI was significantly (P > .05) affected by contrast medium temperature in either sex. VUR was detected in 42 (35.9%) of 117 children studied with warmed contrast medium and in 42 (31.6%) of 133 studied with room temperature medium. Prevalence of VUR was unaffected by contrast medium temperature in children with previously diagnosed VUR and in those studied for the first time. Editorial. Comment: This §imple study shows that temperature does not affect blad.deF volume or the ability to demonstrate reflux. The simplicity of the study makes it noteworthy to the casual observer as an example of simple but effective clinical research. Stanford M. Goldman, M.D.
Incidental Vesicoureteral Reflux in Neonates With An.tenatally Detected Hydronephrosis and Other Renal Abnormalities J. M. ZERIN, M. L. RITCHEY AND A. C. H. CHANG, Section of Pediatric Radiology, Department of Radiology and Section of Pediatric Urology, Department of Surgery, C. S. Mott Children's Hospital, University of Michigan Hospitals, Ann Arbor, Michigan Radiology, 187: 157-160, 1993 Abstract Printed in J. Urol., 150: 1336-1337, 1993
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Neonatal Vesicoureteral Reflux: What Do We Know? R. L. LEBOWITZ, Division of Diagnostic Radiology, Department of Radiology, Harvard Medical School and Children's Hospital, Boston, Massachusetts Radiology, 187: 17, 1993 No Abstract
Editorial Comment: I strongly recommend this article and the somewhat controversial accompanying editorial, which makes the following points. 1) The study demonstrates the usefulness of a computerized data base in clinical research in that it enables one to correlate the imaging information as it affects the care of the patient. 2) The authors show that when hydronephrosis is detected in utero, reflux is the single most common cause. It is so common, according to Lebowitz, that he strongly recommends that all infants with prenatally detected hydronephrosis be given antibiotic prophylaxis until a voiding cystourethrogram can be performed. Breast-feeding and circumcision should also be encouraged in these cases. 3) The report also demonstrates that the background prevalence of reflux is low. In fact, the frequency of reflux in a subset studied was equal regardless of gender, although in boys the incidence of urinary infection was more common and the severity of reflux was higher. Lebowitz recommends that a child with a urinary tract infection be evaluated immediately. 4) The report confirms the International Reflux Study Group findings that if the reflux resolves spontaneously it does so at a much younger age than previously believed. 5) Ultrasound is a poor screening technique for reflux in the neonate. In fact, 25% of the patients with hydronephrosis on prenatal ultrasound had a normal postnatal ultrasound but had reflux on voiding cystourethrography. Lebowitz raises philosophical questions to which there are no answers. By finding patients who are not sick prenatally, are we treating and studying too many patients? I believe that we are not. He also wonders whether several of the children with a normal ultrasound prenatally may, in fact, have reflux. Hopefully, few of these cases will remain undetected before damage to the kidneys occurs. Stanford M. Goldman, M.D.
PEDIATRIC UROLOGY Treatment.of Vesicoureteric Reflux: Results of a Prospective Study R. J. SCHOLTMEIJER, Department of Paediatric Urology, Sophia Children's Hospital, Erasmus University, Rotterdam, The Netherlands Brit. J. Urol., 71: 346-349, 1993 Between 1982 and 1986, 96 children with non-obstructive vesicoureteric reflux were included in a prospective ~tudy. Three patients withdrew from the study and results are therefore presented on 93 children with 135 J/~flµjing ureters who were followed up for at least 5 years. Initially, all children with reflux grade III or less received antibiotic treatment only. Those with reflux grade IV were randomised to antibiotic treatment alone versus surgery plus antibiotic treatment; the primary treatment of reflux grade V was reimplantation. In 85 ureters treated by antibiotics only, reflux disappeared in 64 cases and was reduced in 12. In 50 ureters treated by reimplantation, reflux was cured in 46 cases and no severe ureteric obstruction was seen. Conservative management of reflux grade IV was less successful than surgery. The results of conservative, non-surgical treatment of reflux grades 1-111 were satisfactory, but for grades IV and V surgery should be the treatment of choice if detrusor instability has been excluded.
Editorial Comment: This study reports the late followup of 93 children with 135 refluxing ureters. At 5 years 6 of 11 ureters (55%) with grade 4 reflux showed resolution and 3 demonstrated reduction in grade. However, 7 additional patients with grade 4 reflux initially assigned to medical therapy were crossed over to reimplantation because of breakthrough urinary tract infection or increased reflux. Of the 36 ureters with grade 3 reflux 21 (58%) had resolution at 5 years, 7 (19%) had reduction in reflux grade and 8 (22%) were crossed over to reimplantation because of increasing reflux or breakthrough urinary tract infection. Overall 23 of 105 ureters were subjected to reimplantation because of breakthrough urinary tract infection and/or increasing reflux grade.