Study of assessing diagnostic efficacy of squash smear technique and frozen section by comparing with histopathology in CNS lesions, with special reference to IHC

Abstract

Central nervous system (CNS) squash cytology (CSC) has established itself as a technically simple, rapid, inexpensive, fairly accurate, and dependable intraoperative diagnostic tool. It helps neurosurgeons immensely when management is dependent on it.: To asses the efficacy of squash cytology in the intraoperative diagnosis of CNS lesions by comparing with histopathological diagnosis. The present study is a prospective study done for one and a half year includes 43 patients who presented to the department of neurosurgery with complaints of a headache, backache, epilepsy and radiologically diagnosed to have a space occupying lesion. Only the cases where either squash cytology or frozen section was performed were included in the study. : In the present study, it is observed as Out of 43 cases, squash cytology is performed in 42 cases in which histopathological diagnosis is correlated in 36 cases with a diagnostic accuracy of 85.7%. The diagnostic accuracy of squash cytology in common CNS tumors gliomas and meningiomas was 92.8% and 100% respectively. Out of the 43 cases, the frozen section is performed in 42 cases of which histopathological diagnosis is correlated in 37 cases with a diagnostic accuracy of 87%. The diagnostic accuracy of frozen section in common CNS tumors gliomas and meningiomas was 85.7% and 100% respectively. The sensitivity and specificity of frozen section in the identification of tumor was 94.7% and 100%. The positive predictive value and negative predictive value of the frozen section in the identification of the neoplastic lesion was 100% and 66.6% respectively.Squash cytology and frozen section are preliminary diagnostic methods, which should always be followed by a definitive histopathological diagnosis.