The Cytoscan model E-II in intraoperative parathyroid gland identification in a rabbit model.

BACKGROUND: Intraoperative parathyroid gland identification and preservation is often a challenge even in the hands of experienced surgeons as they could be indistinguishable from fat or thyroid tissue. OBJECTIVE: The goal of this study was to demonstrate the use of the Cytoscan Model E-II, which uses orthogonal polarization spectral (OPS) imaging technology, as an intravital microscope in identifying parathyroid glands intraoperatively and differentiating the parathyroid glands from fat and thyroid tissue in a rabbit model. METHODS: The necks of 4 New England white rabbits were explored with the animals under a general anesthesia. The Cytoscan was used to obtain images of the vasculature of tissue suspected to be parathyroid, fat, and thyroid tissue. These were confirmed by histologic evaluation. RESULTS: All tissues were correctly identified by the Cytoscan and confirmed by histologic analysis. There was an obvious difference in the images obtained of fatty tissue as compared with parathyroid tissues. There was also an appreciable difference between parathyroid and thyroid tissue based on the difference in vascularity. CONCLUSIONS: OPS imaging technology can be used in identifying parathyroid glands based on the difference in vascularity from fat and the pattern and density of vessels when compared with thyroid tissue in a rabbit model. SIGNIFICANCE: The Cytoscan may play a future role in real time intraoperative identification of human parathyroid glands. Future investigation is warranted.

Blindness after bilateral neck dissection: case report and review.

The primary objective of this review of the literature is to identify the probable causes of blindness after bilateral radical neck dissections. This case report and literature review also discusses possible preventive measures that may avert this catastrophic outcome. Cases of blindness after bilateral radical neck dissection were identified by an electronic literature search, as well as cross-checking all references of the above-identified papers. Eleven previous cases of blindness after bilateral neck dissection were identified. The most common cause was posterior ischemic optic neuropathy (PION), which was permanent. We present the only case in the literature in which blindness occurred after radical neck dissections separated by a span of 9 years. The cause of blindness in our patient was posterior ischemic optic neuropathy. Contributing factors included anemia, hypotension, and disruption of collateral venous return from the neck.