Proceedings of the 3rd International Symposium on Orbital Disorders Amsterdam, September 5–7, 1977

We have compiled a series of over 300 consecutive clses of unilateral exoph­ thalmos with definitive diagnosis of the causes of disease process and an adequate follow-up period. Orbital and periorbital tumors constitute 34% of this series, inflammatory diseases including thyroid disorders 50%, arteriovenous abnormalities 4%, and miscellaneous disorders 12%. All patients were thoroughly evaluated clinically and with appropriate diagnostic tests, including ultrasonography (combined A-scan and B-scan), computerized axial tomography (EMI cranial scan), and radiographic tech­ niques (plain films and hypocycloidal poly tomography), orbital venography, and carotid arteriography. Each test was found to have diagnostic capabil­ ities which complemented other studies, depending upon the specific disease process involved. No one test was entirely adequate without the others. Radiographic studies demonstrated bony abnormality in 50% of tumor cases, but in only 28% of the entire series of exophthalmos cases. Primary orbital tumors had a lower hield with radiography than did secondary tumors. Computerized tomography demonstrated diagnostic soft tissue abnormality in 86% of tumors, 43% of inflammatory diseases, and an overall yield of 62% positive results. Ultrasonography proved the most versatile test for evaluation of orbital soft tissues, with 80% positive results for tumors, 87% for inflammatory disorders, and 78% overall acurate diagnosis.