Application of a Novel Miniaturized Histopathologic Microscope for Identifying Cerebral Glioma Margins Rapidly During Surgery

Abstract Rapidly and accurately identifying glioma margins during neurosurgery has significance in reducing the recurrence rate and improving perioperative safety. The purpose of our study is to assess the clinical performance of the DiveScope, a novel handheld histopathologic microscope in rapidly differentiating glioma from normal brain tissue during neurosurgery. Prior to the application of the DiveScope to neurosurgery, we first dissected 3 experimental pigs' brains and observed them under the DiveScope in vivo. Subsequently, 32 ex-vivo specimens from 18 patients were included in the present study. The excised suspicious tissue was sequentially stained with sodium fluorescein and methylene blue and scanned with DiveScope during surgery. The adjacent tissue was sent to the department of pathology for frozen section examination. They would eventually be sent to the pathology department later for hematoxylin and eosin (HE) staining for final confirmation. The positive likelihood ratio (PLR), negative likelihood ratio (NLR), sensitivity, specificity, and area under the curve (AUC) of the device were calculated. In addition, we compared the difference in time consumption between DiveScope and frozen sections for the initial judgment. We also provided a typical case to elucidate the clinical application of the DiveScope in neurosurgery. When HE-stained sections were used as the gold standard, the sensitivity and the specificity of the DiveScope was 88.29% (95% CI: 70.8% − 97.6%) and 100% (95% CI: 39.8% − 100.0%), respectively. In contrast, the sensitivity and specificity of the frozen sections were 100% (95% CI: 87.7% − 100%) and 75% (95% CI: 19.4% − 99.4%), respectively. The AUC of the DiveScope and the frozen sections were 0.946 and 0.875 respectively, with no statistical difference(P = 0.578). Concerning time consumption, in tumorous samples with ≥ 0.8 cm in diameter, the Divescope cost 10.7 minutes on average while frozen pathology cost 41.9 minutes (p < 0.0001). For tumor samples < 0.8 cm in diameter, DiveScope cost an average of 10.7 minutes while the frozen pathology cost 50.1 minutes (p < 0.01). Compared with traditional pathologic examination of frozen sections, DiveScope was faster and displayed an equal accuracy for judging tumor margins intraoperatively.