Utility and Accuracy of Intraoperative Squash Smear Cytology for Intraspinal Lesions: A Cross-sectional Study

Introduction: Intraoperative cytological diagnosis has gained importance because of its technical simplicity, ability to display abnormal cellularity, nuclear and cytoplasmic details. It helps the surgeon to plan the extent of surgery and modify it accordingly. Aim: To study the cytomorphology of spinal lesions by intraoperative squash cytology. Materials and Methods: The present retrospective crosssectional study was conducted for three years from January 2021 to December 2023 at a tertiary care hospital, Mumbai, Maharashtra, India. Total of 72 cases of intraspinal lesions were included in the study. Intraoperative squash smears were made and were stained with rapid Haematoxylin & Eosin (H&E) stain. Paraffin H&E-stained sections were prepared from the residual tissue and additional tissue was sent for histopathology. Smear cytology diagnoses were correlated with histopathological findings. Statistical analysis was done, and diagnostic accuracy was calculated. Results: The study included 72 cases with Male:Female (M:F)=1.8:1. The diagnostic accuracy for schwannoma was highest (21/72), followed by meningioma (19/72) and neurofibroma (9/72). By comparing the results, intraoperative squash smear cytology had a sensitivity of 98.5% and specificity of 75%. The accuracy of the study was 95.8% and three cases were discordant. Conclusion: Intraoperative squash cytology is a fairly accurate, reliable and cost-effective method for rapid diagnosis of Intraspinal lesions. When correlated with histopathological findings, it demonstrates high diagnostic concordance, reinforcing its role as a supportive tool in the intraoperative setting. Its simplicity, rapid turnaround time, and minimal resource requirement make it especially beneficial in resourcelimited settings.