Radiation dose implications of digital angiographic systems.

Digital subtraction angiography (DSA) has been widely accepted and applied. The concentration of iodine in the vessels of interest is low in intravenous DSA. The resultant images can be improved to some extent by increasing the radiation dose. Therefore DSA could become, and possibly could remain, a relatively high-dose procedure. The contributions to dose from the various components of the examination such as fluoroscopy, positioning, test exposures, and final acquisition runs are considered separately. Individual segments of a DSA examination are discussed to show how and where opportunities arise to reduce doses to the lowest levels consistent with satisfactory images.

[Myelolipoma of the adrenal gland in whole-body computed tomography. Report on 2 histologically confirmed cases with clinic-radiological correlations]. / Myelolipom der Nebenniere in der Ganzkörper-Computer-Tomographie. Bericht über zwei histologisch bestätigte Fälle mit klinisch-radiologischer Korrelation.

Myelolipomas are rare non-functioning benign lesions. They occur almost exclusively in the adrenals and are usually small and asymptomatic. We report two cases of unusually large symptomatic myelolipomas of the adrenal which were examined by urography, ultrasound, angiography and computed tomography (CT). A review of the literature of 25 similar cases is presented with a discussion of the pathogenesis. Diagnostic features of an adrenal myelolipoma are (1) a non-functioning, (2) radiolucent, (3) solid and (4) avascular mass arising from the adrenal. With CT the preoperative diagnosis becomes possible by assessing the fat contents, tumor alignment and lack of invasiveness.

Testicular venography as an accurate indicator of true cryptorchism.

It may be impossible to detect a testis on physical examination because of testicular agenesis, testicular atrophy or an intra-abdominal location. When the condition is bilateral, hormonal studies are useful. Inability to locate the testicle at operation is not synonymous with testicular absence. The presence of a testicular vein excludes gonadal agenesis. Visualization of the pampiniform plexus indicates a formed testicle and accurately locates its anatomic site. Four patients with unilateral impalpable testes underwent testicular venography. General anesthesia was used for the first patient only. There were no complications related to the investigation. All four patients underwent exploratory operations that confirmed the testicular venographic findings. Three patients had unilateral testicular dysgenesis or atrophy; one patient had an intra-abdominal undescended testis. Testicular venography is a safe, practical diagnostic investigation in boys with true cryptorchism.

Traumatic aneurysm in the posterior fossa.

A case of traumatic false aneurysm of a branch of the right posterior inferior cerebellar artery is described. Traumatic aneurysms of peripheral intracranial vessels are rare lesions, and a review of the literature reveals only two previously reported cases involving vessels of the posterior fossa.

Lumbar epidural venography. Review of 1,200 cases.

A review of 1,200 lumbar epidural venograms demonstrated venography to be accurate in 98.5% of 595 patients operated on for lumbar disc herniations. Venography is particularly valuable in two situations: first, in extreme lateral disc herniations, which frequently cannot be demonstrated by myelography, and second, if the caudal sac ends more cephalad than usual or tapers sharply, a centrally herniated L5-S1 disc can be missed by myelography. The examination is done on an outpatient basis, causes negligible discomfort, and is essentially free of complications. The authors feel that venography is the examination of choice in the investigation of suspected disc herniation. If there is clinical suspicion of an intradural lesion, myelography should be performed first.

Enterolith causing bleeding in a patient with Meckel's diverticulum. Angiographic demonstration.

Angiography demonstrated a bleeding Meckel's diverticulum supplied by tortuous, presumably embryonic branches of the superior mesenteric artery. A large enterolith, partially impacted into a constriction near the center of the diverticulum, caused a bleeding ulcer. The diverticulum contained no gastric mucosa.

Lumbar epidural venography in the diagnosis of disc herniations.

Epidural venography is a relatively simple and highly accurate method of diagnosing disc herniations in the lumbar region. Good opacification of the epidural venous plexus can be obtained by selective catheterization of ascending lumbar and/or internal iliac veins. Experience with 227 cases is described. The examination appears to be at least as accurate as myelography at the L4-L5 level and more reliable than myelography in cases of lateral disc herniations at L5-SI. Epidural venography is recommended as the examination of choice in patients with suspected lumbar disc herniation.