How Many Grays to Get to the Malfunction of Insulin Pumps? Determining the Effects of Radiation on Insulin Pump Function.

BACKGROUND: The primary objective was to determine if exposure to radiation has an effect on insulin pump function. METHOD: Four donated insulin pumps were filled with saline and set to identical program modes. They were attached together with a dosimeter and exposed to repeat CT scans. RESULTS: Insulin Pump 1 experienced a Prime alarm and a darkened screen during CT scan radiation exposure; this pump was removed from further radiation exposure after 6 CT scans. Insulin Pumps 2, 3, and 4 all continued to receive 34 more consecutive CT scan exposures with no significant alarms, failures, or malfunctions. Insulin Pump 4 experienced Low Battery and Stuck Button alarms, both of which were easily fixed. Insulin Pumps 2, 3, and 4 received a total of at least 8576 mrem from 34 CT scans worth of radiation without any significant alarms, malfunctions, or failures. Insulin Pump 1 was monitored after being removed from the study and continued to function normally with the darkened screen. CONCLUSIONS: It cannot be determined whether Insulin Pump 1 had minor malfunctions due to repetitive use as a demonstration model or due to the radiation exposure. Insulin Pumps 2, 3, and 4 were monitored for 2 additional months following radiation exposure and continued to function normally. Further research studies with a larger number of insulin pumps are warranted to determine the true effect of radiation exposure on insulin pump function

Invasive cervical thymoma masquerading as a solitary thyroid nodule. Report of a case studied by fine needle aspiration.

A 49-year-old woman underwent fine needle aspiration (FNA) biopsy of a presumed thyroid nodule. The initial cytopathologic interpretation suggested a chronic lymphocytic thyroiditis or a malignant lymphoma. The examination of frozen sections during surgery also suggested the presence of a lymphoma. However, histopathologic examination of permanent sections showed the lesion to be an invasive ectopic lymphocyte-predominant thymoma adjacent to the thyroid. Immunoperoxidase staining of FNA cell block sections and permanent sections showed positivity for keratin, proving the epithelial nature of the elongated and spindle-shaped tumor cells. This case high-lights the need to be aware of unusual lesions that may occur in the area of the thyroid; recognizing the potential diversity of thyroid masses that ultimately prove to be of nonthyroid origin should aid in making the correct cytologic differential diagnosis and interpretation of FNA samples obtained from such masses