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Whole-body MRI in the pediatric patient
Abstracts / Clinical Imaging 33 (2009) 490–494 cholangitis. The combination of these two CT findings improved specificity (97% specificity) for the diagnosis of suppurative cholangitis. Conclusion: Papillitis and marked early inhomogeneous enhancement of the liver were found to be the most discriminative CT findings for the diagnosis of acute suppurative cholangitis and for the differentiation between suppurative and nonsuppurative cholangitis
Multidetector computed tomography arthrography of the knee: diagnostic accuracy and indications De Filippo M, Bertellini A, Pogliacomi F, Sverzellati N, Corradi D, Garlaschi G, Zompatori M (Department of Clinical Sciences, Section of Radiological Sciences, University of Parma, Parma Hospital, Via Gramsi 14, I-43100 Parma, Italy). Eur J Radiol 2009;70:342–351. Purpose: To evaluate the diagnostic accuracy and indications of arthrography with multidetector computed tomography (arthro-MDCT) of the knee, in patients with absolute or relative contraindications to MRI and in patients with periarticular metal implants using diagnostic arthroscopy as the gold standard. Materials and Methods: After intra-articular injection of iodixanol and volumetric acquisition, 68 knees in patients of both sexes (30 females, 38 males, age range 32–60 years) were examined with a 16-detector-row CT scanner. The patients had arthralgia but no radiologically detected fractures. They could not be studied by MRI either because of absolute contraindications (subcutaneous electronic implants), surgical metal implants, or claustrophobia. In 37 of 68 patients who had had previous knee surgery, the arthro-CT examination was preceded by an MRI on the same day. All examinations were interpreted by two experienced musculoskeletal radiologists. The findings were compared with arthroscopic findings carried out within 28 days of the CT study. Results: In nonoperated patients, the comparison between arthro-MDCT and arthroscopy showed sensitivity and specificity ranging between 86% and 100%. In the 37 operated knees, arthro-MDCT had an accuracy of 95% compared with 53% of the MRI. Interobserver agreement was almost perfect (K=0.97) in the evaluation of all types of lesions, both on MDCT and on MRI. When arthro-MDCT was compared with MRI in postoperative patients by a McNemar test, a significant difference (Pb.05) was found between these two techniques. Conclusions: Arthro-MDCT of the knee is a safe technique that provides accurate diagnosis in identifying chondral, fibrocartilaginous, and intraarticular ligamentous lesions, in patients who cannot be evaluated by MRI and in patients after surgery.
Rotator cuff tears: value of 3.0 T MRI Lambert A, Loffroy R, Guiu B, Mejean N, Lerais JP, Cercueil JP, Krausé D (16, place du 30 Octobre, F-21000 Dijon, France). J Radiol 2009;90:583–588. Purpose: To demonstrate the value of 3.0-T MR imaging for the detection of rotator cuff tendon tears and surgical planning by correlating imaging findings to surgical findings. Materials and Methods: Prospective follow-up of patients who underwent 3.0-T MR imaging of the shoulder in our department between November 2005 and June 2007. Surgical findings were correlated to imaging findings for 48 patients who underwent surgery: detection, size, partial thickness or complete, and tendon edges. Results: In this patient group, the positive predictive value of MRI for detecting surgical tears was 100% (100% of complete tears and 92% of partial thickness tears). No change in surgical management was recorded when arthroscopy was performed based on MRI findings (size of tear). Conclusion: Three-tesla MRI is valuable for the detection of small tears, especially for partial thickness tears due to increased spatial resolution. The
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identification of surgical candidates and surgical planning are improved due to more accurate measurements of tear size and quality of the tendon edges.
The role of pre-treatment MRI in established cases of slipped capital femoral epiphysis Tins B, Cassar-Pullicino V, McCall I (Department of Radiology, Robert Jones & Agnes Hunt Orthopaedic and District Hospital, Oswestry, Shropshire SY 10 7 AG, UK). Eur J Radiol 2009;70:570–578. Background: Slipped capital femoral epiphysis (SCFE) often results in functional impairment and premature osteoarthritis despite surgical treatment. Treatment decisions are commonly based on the clinical history and radiographic appearance. This study assesses the pretreatment features of SCFE and correlates them to the clinical history to (1) define the underlying pathological mechanisms; (2) correlate the morphological hip abnormalities with the clinical classifications; (3) identify specific magnetic resonance imaging (MRI) features that could carry prognostic implications for treatment approach and outcome. Methods: Clinical history and pre- and posttreatment radiographs and pretreatment MRIs of 14 patients with 15 affected hips were reviewed. Alignment, impingement, fulcrum formation, remodelling, osteopenia, synovitis, joint effusion, bone marrow and soft tissue oedema, and status of the physis and the periosteal sleeve were assessed and related to the clinical history, in particular, history of trauma, duration of clinical symptoms, and ability to bear weight. Results: Bone marrow oedema around the growth plate and joint effusion occurred in all patients. Synovitis occurred in 13 of 15 patients. Six patients had a fall before presenting with SCFE. Five of six had periarticular soft tissue oedema, complete disruption of the physis, and partial periosteal sleeve disruption. Nine patients had no fall prior to presentation; physis and periost were intact in seven of nine; periarticular oedema was not seen. Fourteen of 15 showed evidence of chronic remodelling. Despite an acute clinical history, remodelling was present. A fulcrum-like alignment, impingement of the epiphysis on the metaphysis with a small area of physical contact, was seen in eight patients; six of eight had a prior fall. There was no case of avascular necrosis. Spontaneous reduction of SCFE occurred in one case, the only case without chronic remodelling. With MRI as gold standard, radiographs underestimate the severity of SCFE. Conclusion: Synovitis, periphyseal oedema, and joint effusion are regular features of SCFE. The clinical history and findings are unreliable for the classification of SCFE. Radiographs underestimate the severity of SCFE. SCFE is often a Salter Harris I injury due to a fall with considerable periarticular soft tissue trauma and a potentially unstable alignment of epiand metaphysis. This can lead to spontaneous reduction prior to surgery; MRI can potentially identify unstable, reducible slips. If the mode of surgical treatment depends on the particular nature of the SCFE, then MRI contributes to surgical decision making. Level of evidence: Level 4, case series.
Whole-body MRI in the pediatric patient Ley S, Ley-Zaporozhan J, Schenk J-P (Department of Diagnostic and Interventional Radiology, Section of Pediatric Radiology, University Hospital, Im Neuenheimer Feld 430, D-69120 Heidelberg, Germany). Eur J Radiol 2009;70:442–451. Whole-body MRI is a fast and accurate modality for the detection and monitoring of disease throughout the entire body. For pediatric use, the technique is of special interest twofold: first, it is a radiological method without radiation exposure and, second, it allows for whole-body staging as well as for detailed local evaluation for surgical treatment, thus reducing the number of examinations to be performed in sedation. In the pediatric population, the technique is used for oncological and nononcological (i.e., fever of unknown origin, osteonecrosis) staging and for disease severity assessment of syndromes affecting the whole body. These applications will be reviewed and imaging protocols will be presented.
Multidetector computed tomography arthrography of the knee: diagnostic accuracy and indications De Filippo M, Bertellini A, Pogliacomi F, Sverzellati N, Corradi D, Garlaschi G, Zompatori M (Department of Clinical Sciences, Section of Radiological Sciences, University of Parma, Parma Hospital, Via Gramsi 14, I-43100 Parma, Italy). Eur J Radiol 2009;70:342–351. Purpose: To evaluate the diagnostic accuracy and indications of arthrography with multidetector computed tomography (arthro-MDCT) of the knee, in patients with absolute or relative contraindications to MRI and in patients with periarticular metal implants using diagnostic arthroscopy as the gold standard. Materials and Methods: After intra-articular injection of iodixanol and volumetric acquisition, 68 knees in patients of both sexes (30 females, 38 males, age range 32–60 years) were examined with a 16-detector-row CT scanner. The patients had arthralgia but no radiologically detected fractures. They could not be studied by MRI either because of absolute contraindications (subcutaneous electronic implants), surgical metal implants, or claustrophobia. In 37 of 68 patients who had had previous knee surgery, the arthro-CT examination was preceded by an MRI on the same day. All examinations were interpreted by two experienced musculoskeletal radiologists. The findings were compared with arthroscopic findings carried out within 28 days of the CT study. Results: In nonoperated patients, the comparison between arthro-MDCT and arthroscopy showed sensitivity and specificity ranging between 86% and 100%. In the 37 operated knees, arthro-MDCT had an accuracy of 95% compared with 53% of the MRI. Interobserver agreement was almost perfect (K=0.97) in the evaluation of all types of lesions, both on MDCT and on MRI. When arthro-MDCT was compared with MRI in postoperative patients by a McNemar test, a significant difference (Pb.05) was found between these two techniques. Conclusions: Arthro-MDCT of the knee is a safe technique that provides accurate diagnosis in identifying chondral, fibrocartilaginous, and intraarticular ligamentous lesions, in patients who cannot be evaluated by MRI and in patients after surgery.
Rotator cuff tears: value of 3.0 T MRI Lambert A, Loffroy R, Guiu B, Mejean N, Lerais JP, Cercueil JP, Krausé D (16, place du 30 Octobre, F-21000 Dijon, France). J Radiol 2009;90:583–588. Purpose: To demonstrate the value of 3.0-T MR imaging for the detection of rotator cuff tendon tears and surgical planning by correlating imaging findings to surgical findings. Materials and Methods: Prospective follow-up of patients who underwent 3.0-T MR imaging of the shoulder in our department between November 2005 and June 2007. Surgical findings were correlated to imaging findings for 48 patients who underwent surgery: detection, size, partial thickness or complete, and tendon edges. Results: In this patient group, the positive predictive value of MRI for detecting surgical tears was 100% (100% of complete tears and 92% of partial thickness tears). No change in surgical management was recorded when arthroscopy was performed based on MRI findings (size of tear). Conclusion: Three-tesla MRI is valuable for the detection of small tears, especially for partial thickness tears due to increased spatial resolution. The
493
identification of surgical candidates and surgical planning are improved due to more accurate measurements of tear size and quality of the tendon edges.
The role of pre-treatment MRI in established cases of slipped capital femoral epiphysis Tins B, Cassar-Pullicino V, McCall I (Department of Radiology, Robert Jones & Agnes Hunt Orthopaedic and District Hospital, Oswestry, Shropshire SY 10 7 AG, UK). Eur J Radiol 2009;70:570–578. Background: Slipped capital femoral epiphysis (SCFE) often results in functional impairment and premature osteoarthritis despite surgical treatment. Treatment decisions are commonly based on the clinical history and radiographic appearance. This study assesses the pretreatment features of SCFE and correlates them to the clinical history to (1) define the underlying pathological mechanisms; (2) correlate the morphological hip abnormalities with the clinical classifications; (3) identify specific magnetic resonance imaging (MRI) features that could carry prognostic implications for treatment approach and outcome. Methods: Clinical history and pre- and posttreatment radiographs and pretreatment MRIs of 14 patients with 15 affected hips were reviewed. Alignment, impingement, fulcrum formation, remodelling, osteopenia, synovitis, joint effusion, bone marrow and soft tissue oedema, and status of the physis and the periosteal sleeve were assessed and related to the clinical history, in particular, history of trauma, duration of clinical symptoms, and ability to bear weight. Results: Bone marrow oedema around the growth plate and joint effusion occurred in all patients. Synovitis occurred in 13 of 15 patients. Six patients had a fall before presenting with SCFE. Five of six had periarticular soft tissue oedema, complete disruption of the physis, and partial periosteal sleeve disruption. Nine patients had no fall prior to presentation; physis and periost were intact in seven of nine; periarticular oedema was not seen. Fourteen of 15 showed evidence of chronic remodelling. Despite an acute clinical history, remodelling was present. A fulcrum-like alignment, impingement of the epiphysis on the metaphysis with a small area of physical contact, was seen in eight patients; six of eight had a prior fall. There was no case of avascular necrosis. Spontaneous reduction of SCFE occurred in one case, the only case without chronic remodelling. With MRI as gold standard, radiographs underestimate the severity of SCFE. Conclusion: Synovitis, periphyseal oedema, and joint effusion are regular features of SCFE. The clinical history and findings are unreliable for the classification of SCFE. Radiographs underestimate the severity of SCFE. SCFE is often a Salter Harris I injury due to a fall with considerable periarticular soft tissue trauma and a potentially unstable alignment of epiand metaphysis. This can lead to spontaneous reduction prior to surgery; MRI can potentially identify unstable, reducible slips. If the mode of surgical treatment depends on the particular nature of the SCFE, then MRI contributes to surgical decision making. Level of evidence: Level 4, case series.
Whole-body MRI in the pediatric patient Ley S, Ley-Zaporozhan J, Schenk J-P (Department of Diagnostic and Interventional Radiology, Section of Pediatric Radiology, University Hospital, Im Neuenheimer Feld 430, D-69120 Heidelberg, Germany). Eur J Radiol 2009;70:442–451. Whole-body MRI is a fast and accurate modality for the detection and monitoring of disease throughout the entire body. For pediatric use, the technique is of special interest twofold: first, it is a radiological method without radiation exposure and, second, it allows for whole-body staging as well as for detailed local evaluation for surgical treatment, thus reducing the number of examinations to be performed in sedation. In the pediatric population, the technique is used for oncological and nononcological (i.e., fever of unknown origin, osteonecrosis) staging and for disease severity assessment of syndromes affecting the whole body. These applications will be reviewed and imaging protocols will be presented.