Errors, limitations, and pitfalls in the diagnosis of central and peripheral nervous system lesions in intraoperative cytology and frozen sections.
BACKGROUND
Intraoperative cytology and frozen section play an important role in the diagnosis of neurosurgical specimens. There are limitations in both these procedures but understanding the errors and pitfalls may help in increasing the diagnostic yield.


OBJECTIVE
To find the diagnostic accuracy of intraoperative cytology and frozen section for central and peripheral nervous system (PNS) lesions and analyze the errors, pitfalls, and limitations in these procedures.


METHODS
Eighty cases were included in this prospective study in a span of 1.5 years.


METHODS
The crush preparations and the frozen sections were stained with hematoxylin and eosin method. The diagnosis of crush smears and the frozen sections were compared with the diagnosis in the paraffin section, which was considered as the gold standard.


METHODS
Diagnostic accuracy, sensitivity, and specificity.


RESULTS
The diagnostic accuracy of crush smears was 91.25% with a sensitivity of 95.5% and specificity of 100%. In the frozen sections, the overall diagnostic accuracy was 95%, sensitivity was 96.8%, and specificity was 100%. The categories of pitfalls noted in this study were categorization of spindle cell lesions, differentiation of oligodendroglioma from astrocytoma in frozen sections, differentiation of coagulative tumor necrosis of glioblastoma multiforme (GBM) from the caseous necrosis of tuberculosis, grading of gliomas in frozen section, and differentiation of the normal granular cells of the cerebellum from the lymphocytes in cytological smears.


CONCLUSIONS
Crush smear and frozen section are complimentary procedures. When both are used together, the diagnostic yield is substantially increased.
Department of Pathology, Dr. Baba Saheb Ambedkar Hospital, Delhi, India.
Priyanka
P
Chand
Department of Pathology, Ganesh Shankar Vidyarthi Memorial Medical College, Kanpur, Uttar Pradesh, India.
Sonal
S
Amit
Department of Surgery, Ganesh Shankar Vidyarthi Memorial Medical College, Kanpur, Uttar Pradesh, India.
Raghvendra
R
Gupta
Department of Pathology, Ganesh Shankar Vidyarthi Memorial Medical College, Kanpur, Uttar Pradesh, India.
Asha
A
Agarwal
Central nervous system (CNS) tumors; crush smear; frozen section; intraoperative diagnosis; pitfalls