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CLINICAL RADIOLOGY
Conclusion: Mild hypogonadism in the male, resulting from treatment of Hodgkin's disease, is associated with osteopaenia. LYMPHATIC FILLING IN H I P ARTHROGRAPHY FOLLOWING TOTAL H I P R E P L A C E M E N T S. D. HEENAN, W. C H 1 R A M B A S U K W A and D. J. STOKER
4%. Radiographs were positive in only 14 cases. Clinical follow-up confirmed no false negative scintigrams. We conclude that initial radiographs are mostly non-contributory but add unnecessary cost and irradiation to a young population. From our results, an investigative algorithm has been constructed, with scintigraphy now the first diagnostic step.
Department of Diagnostic Radiology, St George's Hospital, London The significance of lymphatic filling at hip arthrography on prosthetic hips is uncertain. This study investigates the relation between lymphatic opacification and loosening o f total hip replacements. Ninety-one patients were studied retrospectively to determine whether opacification o f lymphatics during hip arthrography correlated with loosening of the prosthetic hip. Plain radiographs were evaluated and a total of 92 hip arthrograms performed. There was radiological evidence of prosthetic loosening at hip arthrography in 61 patients. Fifty-three patients consequently had surgical exploration and 50 were confirmed to have loose and/or infected components. In only 18 patients had lymphatic filling been demonstrated at arthrography. No evidence of loosening was seen in 23 patients. However, lymphatic opacification occurred in 10 of these arthrograms. This study does not demonstrate any correlation between prosthetic loosening, either with or without infection, and filling o f the nearby lymphatic vessels. This finding contradicts an earlier report in the literature. RAD1OLOGICAL APPEARANCES OF THE CERVICAL SPINE 20 YEARS AFFER HALO-PELVIC TRACTION
W. C- G. PEH, A. OHLIN*, K. D. K. LUK* and K. Y. CHIU*
Departments of Diagnostic Radiology and *Orthopaedic Surgery, University of Hong Kong, Duchess of Kent and Queen Mary Hospitals, Hong Kong Halo-pelvic traction (HPT) was extensively used in the management of severe spinal deformities in the past and may cause, odontoid peg osteonecrosis. This study aimed to document resultant long-term cervical spine radiological changes, with clinical correlation. Twenty-five recalled patients (8 men, 17 women) attended clinical review. The average patient was 36.8 years old, had HPT applied at 15.3 years for 29 weeks, and had been followed up for 21.4 years. Initial radiographs were normal in 20 patients (80%) while at final review, only one had a normal radiograph. Abnormalities included degenerative changes (56%), loss of lordosis during extension (52%) and bony fusion (8%). The odontoid peg appeared abnormal in 13 (52%) and indistinct in three cases, requiring axial and direct coronal CT scans. Of 11 CTs performed to date, nine had abnormal odontoid pegs, seven suggestive of osteonecrosis, while two were normal. CT also demonstrated cysts in the atlas (three cases) and neuro-central joint degenerative changes (four cases)~ Most of the patients (88%) were pain-free. Six had mild or moderate neck motion restriction, with one also having mild muscle wasting. Clinical features correlated poorly with radiological abnormalities. Cervical spine radiological changes are common after halo-pelvic traction and are not of clinical significance. 'STRESSED OUT': DIAGNOSIS OF SKELETAL STRESS INJURY IN ELITE ATHLETES R. SHAW, C. M. O'DRISCOLL, R. MITCHELL and J. WILSON*
Radiology Department and *British Olympic Medical Centre, Northwick Park Hospital, Harrow, Middlesex Technetium 99m Methylene Diphosphonate Scintigraphy is widely used for detection of 'stress fracture'. However, plain radiographs are the usual initial investigation performed, before scintigraphy, in athletes referred from the British Olympic Medical Centre (BOMC). This study correlates the clinical, radiographic and isotope sensitivities in detection of stress injury in this group of elite athletes. We retrospectively reviewed 81 athletes from the BOMC with suspected stress injury in a 2 year period (1991-93). Analysis was made of initial investigations, sport, age, sex, site and type of injury, including other modalities used to define or follow up initial results. A total of 88 scintigrams in 81 athletes (46 male, 35 female, mean age 22 years) yielded 53 positive (60%) and 35 negative (40%) results, from a wide cross-section of sports. Commonest sites were lower leg and foot (77%). Common injury types were: stress fracture 65%, stress 'reaction' 15%, direct trauma 12%, insufficiency fracture 4~ and osteochondritis
CHRONIC EXERCISE-RELATED CALF PAIN: MRI ASSESSMENT P. EMBERTON, A. R. MOODY, S. C. BOLTON, D. B. FINLAY, M. J. ALLEN and G. R. C H E R R Y M A N
University Department of Radiology, Leicester Royal Infirmary, Leicester Purpose: This study assesses the role of TurboFLASH contrastenhanced MRI, and conventional spin-echo imaging, in two causes of chronic calf p a i n - medial tibial syndrome (MTS) and chronic calf compartment syndrome (CCCS). Materials and Methods: All investigations were performed using a Siemens Magnetom Impact 1.0 T machine. Eleven patients with a clinical diagnosis of either MTS or CCCS underwent standard axial TI and T2 imaging, repeated in four patients after exercise. Post-Gd-DTPA (Magnevist TM) scanning was used in 10 patients. Dynamic TurboFLASH contrast-enhanced 3-slice scanning was performed during the contrast injection in four patients to assess the early perfusion phase. The scans were reported without clinical information. Compartmental pressures were independently obtained. Results: In one patient with CCCS, early, abnormal, increased signal intensity values were obtained from affected compartments during dynamic scanning, whilst uniform contrast-enhancement profiles were obtained in other patients, All spin-echo sequences were normal in all patients. Post-exercise and non-dynamic post-contrast scanning was unhelpful. All sequences were normal in patients with MTS. Conclusion: TurboFLASH contrast-enhanced dynamic scanning is of benefit in patients with CCCS, but not MTS. Conventional spin-echo MRI was of limited value.
ESSENTIAL HYPERTENSION: IS VASCULAR C O M P R E S S I O N OF T H E LEFT VENTROLATERAL MEDULLA RESPONSIBLE? J. F. M. MEANEY, T. WHALLEY, J. B. MILES, T. E. NIXON, G. H. WHITEHOUSE, E. S. BALLANTYNE and M. W. BOURNE
Departments of Clinical Pharmacology, Radiology and Neurosurgery, Royal Liverpool Hospital & Walton Hospital, Liverpool Recent surgical, post-mortem and angiographic studies have suggested that the cause of essential hypertension may be arterial compression of the left ventrolateral medulla just below the pontomedullary junction. This is the site of the Cl-adrenaline cell nucleus which is intimately involved in the regulation of blood pressure, and the IX (glossopharyngeal) and X (vagus) cranial nerves which mediate the baroreceptor reflexes enter the brain-stem at this level. The theory supposes that pulsatile irritation at this site is responsible for hypertension. Thirty-two patients with essential hypertension and 32 matched controls were scanned prospectively using a FISP 3D sequence, centred over the pontomedullary junction (TR/TE/FLIP 35/7/15 ~ 64 partitions, 55 mm slab). The axial images and operator defined reconstructions were inspected to establish the exact relationships of the (IX) and (X) nerves and ventrolateral medulla to the surrounding arteries. Arterial contact with the left ventrolateral medulla was seen in 26/32 patients with essential hypertension and 8/32 normotensive controls. Essential hypertension may be aetiologically linked to vascular compression of the left ventrolateral medulla at the level of the REZ of IX and X.
M E A S U R E M E N T OF TISSUE BOUND A M I O D A R O N E AND ITS METABOLITES BY C O M P U T E D T O M O G R A P H Y A. A. NICHOLSON and D. M. STEVENTON
Department of Radiology, Hull Royal Infirmary, Hull Amiodarone is strongly tissue-bound and serum levels are a poor guide to therapeutic efficacy. The electrocardiographic measurement of the QT interval corrected for heart rate (QTc) is a better guide but is unhelpful in patients with bundle branch block or U-waves on the electrOcardiogram. Myocardial amiodarone levels are the most accurate guide but are