Use of sentinel node lymphoscintigraphy in malignant melanoma.

Lymphoscintigraphy is a sensitive, inexpensive, relatively noninvasive method of identifying lymphatic drainage patterns and sentinel lymph nodes in patients with malignant melanoma. Lymphoscintigraphy with filtered technetium-99m sulfur colloid allows prompt visualization of the lymphatic system, produces high-quality images, and delivers a low radiation dose to the patient. In addition, good regional lymph node retention is seen with filtered Tc-99m sulfur colloid, improving the success rate of intraoperative gamma probe localization. In combination with surgical localization, lymphoscintigraphy allows preoperative and intraoperative identification of the sentinel node in patients with intermediate thickness melanomatous lesions, obviating radical lymph node dissection in most patients and possibly prolonging their survival. Variables such as tumor location, type and preparation of radiopharmaceutical, injection technique, imaging technique, and prior surgical intervention influence the efficacy of lymphoscintigraphy. Nevertheless, lymphoscintigraphy is recommended as a cost-effective preoperative procedure in all patients planning to undergo elective lymph node dissection. Because of the unpredictability of lymphatic drainage, preoperative scintigraphic findings may lead to changes in surgical management.

Radiographic film fog artifact caused by fluorescent bandage.

Film fog is a common cause of x-ray film artifact. The authors report an unusual source of film fogging in the darkroom--seen in three consecutive radiographs of two different patients--the exposure of film to the low light emission of a fluorescent commercial adhesive bandage worn by the technologist. Heightened awareness of the effects of these bandages will help avoid creation of this film fog artifact.

Computed tomography of adult neuroblastoma.

The computed tomographic (CT) findings in five adult patients with neuroblastoma and in one with ganglioneuroblastoma are presented. Four patients had abdominal and thoracic disease, one had abdominal disease only, and one had isolated chest involvement. The CT findings are nonspecific and may be confused with lymphoma. Nevertheless, multifocal presentation, particularly if it includes the posterior mediastinum and association with diffuse or focal bone involvement, when present, should suggest the diagnosis and lead to appropriate laboratory and histopathologic workup.

Computed tomography of entero-enteric intussusception.

Characteristic computed tomographic findings of entero-enteric intussusception were demonstrated with in vitro studies of surgically created intussusceptions in canine small bowel. The signs were effective in detecting intussusception in two patients, one with metastatic melanoma and a second with a plasmacytoma, both of whom had previously nondiagnostic standard oral contrast medium examinations. The findings consist of a dilated loop of bowel (the intussuscipiens) with a thickened wall, within which is an eccentric soft tissue mass (the intussusceptum) and an adjacent crescentic low density mass on the mesenteric side, representing the invaginated mesentery.

Computerized tomography in the diagnosis of retroperitoneal fibrosis.

We evaluated 4 patients with surgically proved retroperitoneal fibrosis by computerized tomography and ultrasound. Retroperitoneal fibrosis was diagnosed correctly in all 4 patients by computerized tomography but was detected by ultrasound in only 1. On computerized tomography, retroperitoneal fibrosis demonstrated a characteristic soft tissue mass enveloping the abdominal aorta, inferior vena cava and ureters. Computerized tomography was capable of detecting the abnormality with greater reliability than ultrasound, and was far superior in delineating the extent of the process and its relation to adjacent abdominal structures. Computerized tomography is the method of choice in the preoperative evaluation evaluation of retroperitoneal fibrosis. It also is anticipated that computerized tomography will prove equally useful in the postoperative followup of this disease.