Video‐assisted parathyroid gland mapping with autofocusing

Abstract

Preservation of the parathyroid gland (PTG) in neck endocrine surgery is important for regulating the amount of calcium in the blood and within the bones. Localization of the PTG has been attempted using various methods such as ultrasound, sestamibi, computerized tomography, magnetic resonance imaging and indocyanine green fluorescence imaging. These methods cannot be used during surgery, have high sensitivity or have PTG specificity. However, autofluorescence technique has shown high sensitivity and does not require exogenous contrast. In this study, a new optical system was designed and developed into a clinical system. The system enabled easier and faster focusing on the surgical area and high‐resolution video imaging while maintaining a clear image. The system was located above the head of the surgeon. The surgeon was able to see the real‐time autofluorescent image on the monitor next to the operating table at any time to locate the PTG. The PTG buried in the adipose tissue and connective tissue was located easily and accurately. The clinical trial conducted in this study consisted of 56 parathyroid cases in 26 patients. For the statistical results, the sensitivity and accuracy in this redesigned autofluorescent imaging system were 98.1% and 96.4%, respectively.

Emerging Imaging Technologies for Parathyroid Gland Identification and Vascular Assessment in Thyroid Surgery

“…With experience and proper calibration, NIRAF technologies enable earlier and improved PG identification compared with the current gold standard, the surgeon’s unaided eye . The NIRAF imaging can identify 90% to 100% of PGs with 90% to 100% sensitivity and accuracy . In one study, when compared concurrently in the same set of 20 patients, probe-based NIRAF was more sensitive in PG identification vs camera image–based NIRAF (detection rate of 97% and 91%, respectively) .…”

“…[15][16][17] The NIRAF imaging can identify 90% to 100% of PGs 16,[18][19][20][21][22][23][24][25] with 90% to 100% sensitivity and accuracy. 16,21,24,[26][27][28] In one study, when compared concurrently in the same set of 20 patients, probe-based NIRAF was more sensitive in PG identification vs camera image-based NIRAF (detection rate of 97% and 91%, respectively). 19 A meta-analysis of 2062 patients found a 98% sensitivity and 99% specificity of NIRAF (probe or camera based) to identify PG during thyroid surgery.…”

Autofluorescence and Indocyanine Green in Thyroid Surgery: A Systematic Review and Meta‐Analysis

“…Therefore, NIR‐AF is not a “one‐shot” procedure, but the surgeon can use it multiple times during the entire procedure whenever it is considered appropriate. Recently, some authors introduced the concept of “parathyroid mapping,” 20,42 or a systematic approach on PG identification with different steps: first stage images (P1) were obtained by the surgeon before dissection pointing the camera at predicted locations of PGs; the second stage (P2) was performed after the surgeon dissected or identified PGs with the naked eye not visualized in stage 1; third stage images (P3) were then taken from removed surgical specimens when PGs were not detected in stages P1 or P2.…”

Recent Advances and the Potential for Clinical Use of Autofluorescence Detection of Extra-Ophthalmic Tissues

“…Kim et al constructed an experimental setup based on a digital single-lens reflex camera with the aim of designing a PTG detection tool for thyroidectomies. They reached a PTG detection rate of 100% (n = 8) and 98.6% (n = 38) prior to surgical dissection with the system taking photographic images [97,104] and 98.1% with an improved autofocusing video-imaging system [105]. Feasibility studies on case series of parathyroidectomies found high (98.8%-100.0%) intraoperative PTG detection rates with different technical setups [98,106].…”