at seven sites on the operator and at fi ve sites on the patient. RESULTS: The mean number of digital subtraction angiography studies and fluoroscopy time were 21 ::':: 10 and 73 ::':: 24 minutes, respectively. The equivalent dose range at each site in the operator was 0.12 to 0.88 mSv (glabella}, 0.06 to 1.1 and 0 to 0.09 mSv (neck, outside and inside the protector, respectively}, 0 to 0.20 mSv (left shoulder, inside the protector), 0.09 to 1.99 mSv (left arm), 0.05 to 3.55 mSv (left hand}, and 0 to 0.49 m Sv (pubis, inside the protector). Those in the patients were 3.1 to 136 mSv (glabella), 13 to 5441 mSv (right temporal area), 4 to 186 mSv (left temporal area), 0.1 to 51 mSv (neck}, and 0 to 0.62 mSv (pubis}. CONCLUSIONS: The total doses at the operator's eyes and left hand during the course of a year may exceed the dose limits recommended by the International Commission on Radiological Protection. Operators should wear not only body protectors, but also thyroid protectors and lead glass spectacles. The equivalent dose at the right temporal area of the patient m ay exceed the deterministic dose for transient erythema or alopecia of the skin even in one endovascular procedure. Index terms: Radiation, dose; Radiation, exposure in diagnostic procedures; lnterventional neuroradiology, complications of; Iatrogenic disease or disorder AJf'IR Am J f'leuroradio/15:1801-1808, Nov 1994 Although there has been marked improvement of the technology used in interventional neuroradiology, the exposure dose of operators, medical staff, and patients is a matter of concern. Endovascular surgeries of the head and neck take much more time than do routine diagnostic x-ray examinations, which necessarily results in increased risk of radiation exposure of the medical staff and patient. Although the International Commission on Radiological Protec - tion has conducted research to establish international standards for exposure dose and radiologic protection ( 1), there have been few reports concerning the dose in endovascular surgery. We therefore measured the equivalent doses to the operators and the patients in 15 endovascular surgeries of the head and neck. Materials and Methods Fifteen patients, seven m ale and eight female, ranging from 17 to 71 years of age, were included in the study (Table 1). The endovascular procedures consisted of su - perselective embolization for brain arteriovenous malformations in three patients, dural arteriovenous fistulas of the cavernous sinus in six, dural arteriovenous fistulas of the posterior fossa in two, and, in one each, traumatic arteriovenous fistula of the face, glomus tumor of the neck, Received January 5, 1994; accepted after revision June 24. From the Departments of Neurosurgery (N.K., A.T. , S.E., M.N.) and Radiology (T.K.), Toyama Medical and Pharmaceutical University, Toyama, Japan. Address reprint requests to Naoya Kuwayama , MD, Department of Neurosurgery, Toyama Medical and Pharmaceutical University, 2630 Sugitani, Toyama 930-01 Japan. AJNR 15:1801-1808, Nov 1994 0195-6108/94/1510-1801 © American Society of Neuroradiology hemangioma of the face, and traumatic aneurysm of the superficial temporal artery. They included nine transarterial and six transvenous procedures. The operator wore a body protector, a thyroid protector, and lead glass spectacles. The x-ray device used was an automatic exposurecontrolled fluoroscope (Angioskop, Siemens, Erlangen, Germany) and a digital subtraction angiography system (DPS-4 1 00, Adac Laboratories, Milpitas, Calif). The dis1801 1802 KUWAYAMA TABLE 1: Fifteen patients undergoing endovascular procedures Patient Age/ Sex Diagnosis Method 1 57/M AVF of the face TAE 2 49/ F dural AVF of the cavernous sinus TAE 3 28/M brain AVM (grade Ill) TAE 4 62/ F dural AVF of the