British Medical Ultrasonics Group 63

made of the potential of a number of commercial machines to display amplitude information on film as a range of grey shades. The limitations are discussed and methods of improvement suggested.

12. An Evaluation of Grey Scale Ultrasonography K. J. W. TAYLOR, D. A. CARPENTER, V. R. MC- CREADY and C. R. HILL

Department of Nuclear Medicine, Royal Marsden Hospital and Institute of Cancer Research, Downs Road, Sutton, Surrey, England

Grey Scale ultrasonography has been applied to obstetric examination by Kossoff at N.A.L., Sydney and to cancer diagnosis at the Royal Marsden Hospital. Commercial machines are becoming available with grey scale display and

the applications of such techniques have been evaluated. At present, the technique has little advantage over the

conventional one in cardiology, urology, ophthalmology or for fetal cephalometry. However, scans will be shown which demonstrate the enhanced intra-fetal detail which may be obtained and the improved placental display which renders placental localisation a highly accurate procedure in unskilled hands.

The technique is essential for theadequate examination of liver, spleen and thyroid, Selective amplification of the low level echoes permits the internal consistency of the organ to be displayed. Diffuse pathologies of both liver and spleen can be reliably differentiated as well as visualisation of small space-occupying masses. Similarly, in the thyroid gland, swellings may be differentiated into benign adeno- mata, cysts and malignancies.

The technique has found extensive application in the inves- tigation of a wide varlet# of common diagnostic problems.

OSTERREICHISCHE GESELLSCHAFT FUR ULTRASCHALL IN DER MEDIZIN

The 3rd Annual Meeting of the Austrian Society for Ultrasound in Medicine was held in Vienna on 14De- cember 1974. The following papers were presented.

1. Duppler-Sonography and Echo-Orbitography in Orbital Vascular Processes P. TILL and M. R. LESSEL University of Vienna, Austria

In the presence of vascular processes of the orbit Doppler- Sonograms are different from the normal types and the sonograms can be recorded from larger areas. Doppler- Sonograms of the following pathological findings were demonstrated: orbital vascular congestion, racemous angioma, carotid-cavernous sinus, fistula and vasculanzed solid tumor. In the presence of cavernous hemangioma the vascular spaces remain sonographically silent. In arteritis temporalis the Ooppler-Sonogram is extinguished over the entire orbit including the areas of central retinal artery and superficial temporal arteries.

2. Estimation of the Duration of Gestation by means of Ultrasonic B-scan Technique H. KUCERA and E. REINOLD

University of Frauenklinik. Vienna. Austria.

The foetal transverse diameter and the longitudinal diameter has shown a good correlation with the duration of gestation, the mean and its 95 per cent confidence interval are very small. The anterior posterior diameter has shown a poor correlation.

3. Ultrasonography in Renal Transplants P. MAYRHOFER and CH. JANTSCH

Ludwig-Boltzmann Institute and University Medical Clinic, Vienna, Austria

There is no difference between the B-scan of a normal kidney in a regular position and the B-scan of a renal trans- plant. Changes in transplant size are measured because of its known significance in rejection. In patients with renal obstruction and dilation of the renal pelvis in hydro-

nephrosis, the kidneys show a C shaped pelvic echo pattern or a ring pattern.

Perirenal fluid collections can easily be detected with this method, as a sonolucent area beside the kidney. Ultrasonic laminography is readily adaptable for the initial and follow- up evaluation of patients undergoing human renal allotrans- plants.

4. Echoencephalography in Acute Subdural Effusions G. LANNER and O. SCHR6TTNER

Neurosurgical Unit of the University Hospital. Graz. Austria

Echoencephalography has been a routine investigation in more than 3000 patients suffering from severe head injury since 1965. in about 30 per cent of these patients unilateral contusion of the brain caused only a moderate contralateral displacement of the midline, the shift ranging between 2 and 3 mm. A larger shift exceeding 5 mm was seen in more than two-thirds of patients with unilateral subdural hematoma later confirmed by surgery. Midline shift were most frequently seen in clots of the temporal region, whereas those in the frontobasal and occipital areas sometimes eluded detection. These as well as bilateral hematomas still remain a problem, since detection becomes possible only if the hematoma echo can be seen.

5. The Diagnosis of Pseudotumours of the Macula by means of ultrasonography

H. FREYLER

University of Augenklinik, Vienna. Austria

The echograms of 35 patients affected with pseudo- tumours of the macula were analysed in detail. Pseudo- tumours and malignant melanomas can be distinguished by means of ultrasound with a high probability if the minimal prominence of the tumour is not lower than 1. I mm, and with certainty if the minimal prominence is not tess than 1.5 mm. The echogram of pseudotumours is mainly characterized by its extraordinary irregularity resulting from the irregular histologic structure of these lesions.

64 British Medical Ultrasonics Group

6. Ultrasonic Assessment of Left Ventricular Con- tractility Following Administration of Vasoactive Drugs G. STEFAN

J udendorf-Strassengel, Austria

Plotting the left ventricular internal dimensions or the midpoint distance at 50 msec intervals against the elapsed time on a high quality echogram for a number of heart cycles, one can establish a curve, which represents the course of left ventricular contraction during ejection period.

Curves for various drugs were constructed establishing the inotropic, chronotropic and dromotropic effect prior to, during and after administration of the drugs.

It could be shown, that solely by means of this curve, it is possible to obtain reliable qualitative and quantitative information on alterations of the contractile state of the left ventricular myocardium in patients, who are subjected to therapy with vascoactive drugs.

7. Echography in Diseases of Periorbital Sinuses H. FROHWALD and P. TILL

University of Vienna, Austria

A-scan echography, as used for the examination of the orbit, can reveal defects in the bony orbital wall and detect tumor tissues in the sinuses outside the orbit. The extension of such a lesion can be measured in directions where the sound beam passes through a bone defect. The following criteria help differentiate between the two main groups of lesions: (1) Muco-pyoceles are large, regularly shaped and sharply outlined. A single, large, regularly outlined bone

defect is the rule. Usually, double spikes from the cyst wall can be displayed. (2) Periorbital malignancies such as carcinoma and, less frequently, sarcoma--by contrast-- show irregular structures and borders. They usually have a low reflectivity similar to that of mucopyoceles: single higher spikes, however, within the pattern are the rule. Often spontaneous movements from single spikes can be seen (blood flow from larger tumor vessels). Results: in 25 histologically verified cases of mucoceles the differential diagnosis was correctly made by echography in 24 cases. In 20 histologically verified cases of periorbital malignancies the differential diagnosiswas correctly made by echography in 18 cases.

8. The Role of Ultrasound in the Diagnosis of Soft Tissue Hematomas in Hemophilic Patients CH. JANTSCH

University of Vienna, Austria

Ultrasound scanning permits, for the first time, direct visualization of soft tissue hematomas. Since the test is non- invasive, causes no discomfort and does not expose the patient to ionizing radiation, it can hence be ordered without hesitation, even in small children. One illustrative case, where ultrasound permitted differentiation between acute appendicitis and an intramuscular hematoma is presented.

Based on the examination of 29 cases the use of ultra- sound scanning for the follow-up of soft tissue hematomas in hemophilia patients is shown.

N E D E R L A N D S E V E R E N I G I N G voor U L T R A G E L U I D in de G E N E E S K U N D E en de BIOLOGIE

The Annual Scientific Meeting of the Dutch Society for Ultrasound in Medicine and Biology was held in Utrecht on 17 October 1974. The meeting was largely devoted to a discussion, under the chairmanship of the President, Dr. J. Somer, of a comparison of two commercially available

grey-scale ultrasonic scanners--the Kretz Combison I1 and and Picker E.D.C. The discussion was preceded by a paper on Grey-scale Echography by J. M. Thijssen of the Ophthal- mological Biophysics Laboratory at the University of Nijmegen.