ABSTRACTS 335

THE A C C U R A C y OF COMPUTED TOMOGRAPHY IN THE INTRA-ABDOMINAL STAGING OF RENAL CELL CARCINOMA EAMANN BREATNACH Mater Misericordiae Hospital, Dublin

diagnostic accuracy. To our knowledge, no such study has pre- viously been performed. Normal, premature and vomiting infants were examined using a real-time sector scanner with either a 5 MHz or a 7.5 MHz probe.

To assess the accuracy of abdominal computed tomography in staging renal cell carcinoma, an analysis of 42 patients was made. Patients were aged from 35 to 83 years and only those where the tumour was thought resectable were included. In each patient abdominal computed tomography scan results were compared with pathologically proven surgical staging according to the classification of Robson.

Sensitivities and specificities calculated were as follows:

Stage 1 disease (tumour confined within the renal capsule): sensitiv- ity 80%, specificity 75%, overall accuracy 83%.

Stage 2 turnouts (tumour extending beyond renal capsule but confined with Gerotas fascia): sensitivity 66%, specificity 97%, overall accuracy 95%.

Stage 3 turnouts (I.V.C. involvement): sensitivity 78%, specificity 85%, overall accuracy 83%.

Stage 3 (lymph node involvement): sensitivity 71%, specificity 91%, overall accuracy 88%.

Stage 4 (tumour extending beyond Gerotas fascia): sensitivity 33%*, specificity 81%, overall accuracy 71%.

(* Note that patient selection excluded those with pre-operatively suspected adjacent organ or abdominal wall involvement.)

The pitfalls in interpretation for each stage will be discussed and illustrated and a discussion on the role of computed tomography in staging renal cell carcinoma will be presented.

Results 1 The muscle thickness and the total diameter vary in the individual

patient but are maximal immediately after a feed. 2 The examination must be performed immediately after feeds. 3 The symptoms of pyloric stenosis are possible when muscle

thickness measures less than 0.4 cm or total diameter is less than 1.5 cm.

4 The pylorus may not be palpable when less than 1.5 cm in diameter.

5 The value of the ratio of pyloric volume to body weight will be discussed.

ULTRASOUND EVALUATION OF RENAL VOLUME IN CHILDREN. A COMPARISON WITH DMSA SCANNING J. HOWARD and G. M. STEINER Children's Hospital, Sheffield

This study aims to determine whether simple measurements of kidney volume made by ultrasound examination can give a satisfac- tory estimate of the relative functions of the two kidneys. The results of the ultrasound measurements will be compared with the results of DMSA isotope examinations.

The comparison will be made for hydronephrotic and non- hydronephrotic kidneys. Assessments of renal scarring will also be made.

R A D I O D I A G N O S I S C h a i r m a n : D r W . H a t e l y

ULTRASOUND APPEARANCES OF THE OVARIES AND UTERUS IN ANOREXIA NERVOSA P. A. L. GORDON, J. L. TREASURE, E. A. KING, M. WHEELER and G. F. M. RUSSELL St Thomas' Hospital & Institute of Psychiatry, London

The changes in ovarian and uterine morphology during weight-gain in patients with anorexia nervosa are described. Eleven patients had a minimum of four sequential pelvic scans. Ovarian volume was initially smaller than in normal women but increased logarithmically with weight-gain. The internal structure of the ovaries was initially homogeneous but with increased weight multiple small cysts (2- 5 mm diameter) were demonstrated. Development of larger cysts (6-10 mm) occurred in five patients. Accelerated growth of one cyst (>10 mm) then occurred and in two patients this was associated with menstruation.

The uterine cross-sectional area increased slightly with the development of intraovarian cysts and markedly in those patients who subsequently menstruated (to 17.5cm 3 compared with 13.6 cm 3 in the non-menstruating group).

The return of reproductive function as shown ultrasonically is backed up by the hormonal data which demonstrated an increase in basal luteinising hormone throughout the period of weight gain. Oestradiol levels were significantly increased at each stage of ovarian intrastructural development.

It is concluded that ultrasound is an important adjunct in the management of patients with anorexia nervosa.

ULTRASOUND APPEARANCES OF INFANTILE HYPERTROPHIC PYLORIC STENOSIS - A NEW FORMULA? R. A. CARVER, M. OKORIE, G. M. STEINER and J. A. S. DICKSON Children's Hospital, Sheffield

Previous studies on the ultrasonic appearances of infantile hyper- trophic pyloric stenosis have utilised isolated measurements of length, breadth or muscle thickness of the pylorus in order to define upper limits of normal for such measurements. The aim of this clinico-radiological study was to assess pyloric volume from these measurements and to compare this with body weight in normal infants and in those with pyloric stenosis, with a view to improving

COULD WE BE DOING FEWER INTRAVENOUS UROGRAMS? D. J. MOORE, D. R. NAIK and B. JAGJIVAN Royal Hallamshire Hospital, Sheffield

Intravenous urography (IVU) is, at best, unpleasant for the patient and carries a small, but real risk of a serious adverse reaction or even death. With the advent of newer imaging modalities, particu- larly ultrasound, many IVU's should be avoidable. With a view to clarifying what seems a confused situation we have compared the IVU and ultrasound studies on 350 adult patients. We have attempted to answer two basic questions 'What can ultrasound do (and not do)' and 'on which patients can an IVU be safely omitted without loss of diagnostic information'.

We will present the results of our study and discuss the conclusions which we have drawn from it. This information should have implications for all clinicians requesting IVU's and should assist in the rational use of these two investigations.

PRE-NATAL DETECTION OF FETAL CHOROID PLEXUS CYSTS S. OSTLERE, J. GROVES and H. C. IRVING St James' University Hospital, Leeds

Many centres in the UK perform a routine antenatal ultrasound scan at 16 to 18 weeks, and an essential part of this examination is the demonstration of the anatomy of the ventricular system within the fetal head. Abnormalities of the ventricular dimensions have been well described but the significance of some other abnormal findings is less certain.

Cysts in the choroid plexus of the lateral ventricles of the fetus have been detected on ultrasound examinations in early pregnancy in nine patients. The cysts were solitary in three cases, multiple and bilateral in five, and multiple and unilateral in one.

The progress of the cysts in these nine fetuses is being monitored with follow-up scans during pregnancy, and it. is also intended to perform cranial ultrasound scans in the neonatal period. Spon- taneous resolution of the cysts between 21 and 34 weeks of gestation has already been documented in four of the cases under study.

The results of the subsequent scans and the outcome of all the pregnancies in this study will be reported, in an effort to establish the true significance of the pre-natal detection of cysts in the fetal choroid plexus.