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CLINICAL RADIOLOGY
eehocardiography in investigating a potential source of thrombus in embolic disease. Even if further abnormalities are demonstrated by T O E or M R I , this does not appear to affect patient m a n a g e m e n t and these expensive and unpleasant investigations are best avoided at the present time.
USE OF INTRAOPERATIVE TRANSOESOPHAGEAL E C H O C A R D I O G R A P H Y D U R I N G M I T R A L VALVE R E P A I R A. C. DE SOUZA, R. K E A L and T. SPYT
Departments of Cardiothoracic Surgery and Radiology, Groby Road Hospital, Leicester Mitral valve repair is increasingly accepted as the procedure of choice for regurgitant mitral valves. The choice of surgical technique depends on the accurate diagnosis of pathology of the valve prior to surgery. Transoesophageal echocardiography (TOE) allows accurate assessment of the valve prior to and after repair. Since January 1992, 30 patients have undergone mitral valve repair following intraoperative assessment by single plane transoesophageal echocardiography. The pathologies demonstrated include anterior leaflet prolapse, posterior leaflet prolapse, cleft mitral valve and dilated annulus. These were confirmed intraoperatively. We will also show the post-operative appearances. The usefulness of transoesophageal echocardiography during mitral valve surgery is confirmed. There are a number of technical problems associated with setting up the service as welt as finance and resource limitations. Despite these T O E appears cost effective in terms of the saving on valve expenditure.
A U D I T OF P A T I E N T AND O P E R A T O R E X P O S U R E T O I O N I Z I N G RADIATION D U R I N G C A R D I A C CATHETERIZATION R. K E A L , C. REEK and M. D U N N
In conclusion, the generalized atrophic changes seen post liver transplantation are likely to be related to the underlying end stage chronic liver disease. Neurological complications occurred in 19 out of a total of 320 patients who underwent liver transplantation.
T H E R A D I O L O G I C A L A P P E A R A N C E S OF F A M I L I A L PITUITARY APOPLEXY A. K. BANERJEE, J. P O W R I E , B. A Y E R S and P. H. S O N K S E N
Department of Radiology and Endocrinology, St Thomas" Hospital, London Pituitary apoplexy is the sudden expansion of a pituitary a d e n o m a due to acute infarction or haemorrhage into the gland. The incidence of haemorrhage into pituitary tumours varies from 1.5% to 27.7%. Diagnosis m a y be difficult on CT scans and M R I imaging is usually required, especially in the subacute cases. We present two cases of pituitary apoplexy occurring in a 48-year-old m a n and his 19-year-old daughter. O n CT scanning, an acute pituitary haemorrhage is diagnosed by demonstrating hyperdense blood in a t u m o u r within an enlarged sella. Chronic haemorrhage, however, may be difficult to differentiate from cystic tumours on CT. O n M R I examination a hyperintense signal in a pituitary t u m o u r on a T1weighted image in the clinical context of a headache is suggestive of a pituitary haemorrhage. The intense signal is due to dilute free methaemoglobin from red cell lysis which shortens the T1 relaxation time. Wc are unaware of any previously reported familial cases of this condition.
T H E R O L E OF C O M P U T E D T O M O G R A P H Y IN T H E D I F F E R E N T I A L D I A G N O S I S O F CYSTIC NECK L E S I O N S G. J. M. G O H , E. D. V A U G H A N and H. G. LEWIS-JONES
Departments of Radiology and MaxilloJacial Surgery, Aintree Hospitals, Liverpool
Department of Cardiac Radiology, Groby Road Hospital, Leicester Cardiac catheterization is a commonly performed procedure involving the use of ionizing radiation, often by non-radiologists. There is concern over the radiation dose particularly during interventional procedures, both to the patient and operator. We have undertaken an audit in our department during the past year with regard to both patient and operator dose. The screening time and film length for procedures undertaken in the catheter rooms has been recorded on a computer database for the past 2 years. In addition, since June 1991, dose area product readings have been available from a Diamentor installed in one of our catheter rooms. We have analysed the results from this database and compared the methods of recording. The results show that the average screening time for diagnostic cases is 4.8 min, compared with 15.8 rain for PTCA. However, the average patient dose is 7.0 mSv for diagnostic studies compared with 11.5 mSv for PTCA. We have also related the operator dose to the total patient exposure during procedures performed by that operator. The results show a close correlation in most cases, but some discrepancy in others. The reasons for this are discussed. The estimated expected operator dose during diagnostic cardiac catheterization is 0.04 mSv/100 m c i n e film.
H E A D CT SCANS IN LIVER T R A N S P L A N T S O. C H A N
Department of Radiology, King's College Hospital, London A retrospective study was performed of all the patients who underwent liver transplantation and who had head CT scans. Of 320 patients who underwent liver transplantation, 50 patients had 82 head C T scans. There were 14 paediatric and 36 adult patients. There were nine patients who underwent acute liver transplantation and 41 underwent elective liver transplantation for mainly end stage liver disease. Nineteen of the 50 patients had evidence of cerebral or cerebellar atrophy and only one of these patients had an acute liver transplant. This patient had a CT scan 2 m o n t h s after liver transplantation. There were 19 focal lesions seen which included 4 abcesses, 2 infarcts, 2 haemorrhages, 1 glioma, 1 lymphoma, 1" cyclosporin toxicity, 1 arteriovenous malformation and a brain stem abscess not seen on CT.
We describe the Computed Tomographic (CT) appearances of 28 cases which presented clinically as mass lesions of the neck. Contrastenhanced C T was performed as part of the primary investigation. In all 28 cases, there was a predominant cystic appearance of the mass lesion in the neck. In the group studied, there were nine different diagnoses ranging from benign lesions such as branchial cleft cysts, plunging ranulae and h a e m a t o m a to malignant lesions such as salivary gland tumours, lymph node metastases and lymphoma. CT can determine if the lesion is solid or cystic, whether it is single or multiple, assess the cyst wall and the presence or absence of septations and demonstrate the precise anatomical location of the cyst and its relationship with other structures in the neck. All these features are of value in establishing a limited differential, if not specific diagnosis in each case.
AN A U D I T OF C O M P U T E D T O M O G R A P H I C ARTHROGRAPHY OF THE PATELLO-FEMORAL JOINT G. J. M. G O H and B. E. EYES
Department of Radiology, Aintree Hospitals, Liverpool Computer tomographic (CT) arthrography has been described as a far superior technique to plain fihn radiography in the assessment of the patello-femoral joint, especially in its ability to demonstrate patellofemoral malalignment. CT arthrography of the patello-femoral joint was introduced into our department and an audit of the first 30 patients with anterior knee pain who underwent this procedure was performed. We specifically looked at the influence of CT arthrography on further clinical m a n a g e m e n t and outcome of the patient. The diagnosis and consequently the further management was altered in 10 (30%) of the cases studied. Most of these patients were initially not thought to have patello-fernoral malalignment but following CT arthrography, this was found to be the diagnosis. These patients proceeded to surgery, with five patients responding well. Conversely, two patients avoided surgery following CT arthrography. We wish to highlight the importance of CT arthrography of the patello-femoral joint in evaluating patient with anterior knee pain and in influencing their further clinical management.