Contact endoscopy for intraoperative parathyroid identification.

Experienced thyroid surgeons are often able to identify the parathyroid glands, but sometimes it is difficult to differentiate them from other contiguous tissues. Contact endoscopy was introduced in otolaryngology for the characterization of normal and pathological epithelia. Our objective was to analyze contact endoscopy as an auxiliary method for identification of the parathyroid glands during thyroid surgery. Five total thyroidectomies and 5 hemithyroidectomies were performed in September 2001. After surgical exposure, contact endoscopy was performed. A total of 15 peritracheal regions were studied. Superior and inferior parathyroid tissues were identified on the basis of color, size, and probable location. Contact endoscopy was performed before and after use of methylene blue stain. Contact endoscopy was also used in neighboring areas. We compared the visual impression to the contact endoscopy findings. Two structures were visually supposed to be the superior and inferior parathyroid glands in each case. From 30 visually supposed glands, 25 were confirmed by telescope. Of the other 5 structures initially supposed to be parathyroid tissue, 3 were adipose tissue and 2 were thyroid parenchyma. In the 5 cases in which the identification of one of the glands was not confirmed, an additional contact examination enabled us to further identify parathyroid glands in 3 cases in which structures were initially identified as adipose tissue. Contact endoscopy is an efficient auxiliary method for the identification of the parathyroid glands during thyroid surgery that poses little risk of morbidity to the patient.