Background: Intraoperative consultation for neurosurgical specimens can be difficult at times, despite the use of both frozen section and squash preparation. Various factors influence the diagnostic accuracy of these procedures. This study was conducted to evaluate reasons for discordant case results in neurosurgical intraoperative consultations and make a comparative analysis of these two commonly used methods to identify the possible pitfalls, errors, and limitations.
Materials and methods: All the neurosurgical cases received in the Department of Pathology for intraoperative consultation over a period of 3 years were studied retrospectively. The slides of frozen sections and squash preparation were retrieved and the diagnosis was compared with the final diagnosis given on paraffin-embedded sections.
Results and observations: A total of 6% of the cases were found to be discordant; these included angiomatous meningioma, Non-Hodgkins lymphoma, metastatic renal cell carcinoma, cerebellopontine angle fibrous meningioma, and craniopharyngioma. Highly vascular lesions, unavailability of squash preparation in a few cases and technical errors like thick smears, excessively crushed specimen, freezing, and cautery induced and crushing artifacts contributed to misdiagnosis.
Conclusion: The discrepant cases need to be reviewed regularly by pathologists to familiarize themselves with the morphological changes and artifacts. The knowledge of possible errors could minimize misinterpretation and help in providing a more conclusive opinion to the operating surgeon.