Early diagnosis of acromegaly: computers vs clinicians.

BACKGROUND: Early diagnosis of a number of endocrine diseases is theoretically possible by the examination of facial photographs. One of these is acromegaly. If acromegaly were found, early in the course of the disease, morbidity would be lessened and cures more likely. OBJECTIVES, DESIGN, PATIENTS, MEASUREMENTS: Our objective was to develop a computer program which would separate 24 facial photographs, of patients with acromegaly, from those of 25 normal subjects. The key to doing this was to use a previously developed database that consisted of three-dimensional representations of 200 normal person's heads (SIGGRAPH '99 Conference Proceedings, 1999). We transformed our 49, two-dimensional photos into three-dimensional constructs and then, using the computer program, attempted to separate them into those with and without the features of acromegaly. We compared the accuracy of the computer to that of 10 generalist physicians. A second objective was to examine, by a subjective analysis, the features of acromegaly in the normal subjects of our photographic database. RESULTS: The accuracy of the computer model was 86%; the average of the 10 physicians was 26%. The worst individual physician, 16%, the best, 90%. The faces of 200 normal subjects, the original faces in the database, could be divided into four groups, averaged by computer, from those with fewer to those with more features of acromegaly. CONCLUSIONS: The present computer model can sort photographs of patients with acromegaly from photographs of normal subjects and is much more accurate than the sorting by practicing generalists. Even normal subjects have some of the features of acromegaly. Screening with this approach can be improved with automation of the procedure, software development and the identification of target populations in which the prevalence of acromegaly may be increased over that in the general population.

Combined use of calcium infusion localization and a minimally invasive surgical procedure in the management of insulinoma.

OBJECTIVE: To review our experience with current diagnostic localization techniques and a minimally invasive laparoscopic surgical procedure in the management of insulinoma. METHODS: We describe five patients with insulinoma, the results of diagnostic studies, and a proposed algorithm for management of this rare tumor. RESULTS: Four female patients and one male patient (age range, 34 to 72 years) underwent supervised fasting (mean duration, 12 hours; range, 3 to 28 hours) to establish the diagnosis of insulinoma. These patients had glucose values that ranged from 38 to 41 mg/dL and associated serum insulin levels of 11.3 to 61 microU/mL. C-peptide values ranged from 3.4 to 11.5 ng/mL, and proinsulin levels (measured in four patients) were 32.9 to 82 pmol/L. These biochemical findings were diagnostic for insulin-mediated hypoglycemia, and the high proinsulin and C-peptide levels, in conjunction with negative results of serum measurements for sulfonylureas, excluded an exogenous source of insulin as the cause of hypoglycemia. Four of the five study patients had nondiagnostic results of noninvasive localization studies and underwent selective arterial injection of calcium with hepatic venous sampling to help localize the insulinomas within the pancreas. This procedure correctly localized the lesion in three patients and was associated with no complications. In all five patients, surgical resection of a solitary insulinoma (with use of laparoscopic procedures in four, one of which was converted to an open procedure) yielded resolution of the hypoglycemia. CONCLUSION: The combination of calcium infusion localization and a minimally invasive surgical procedure is an efficient management approach in the diagnosis and treatment of insulinoma.