Optic nerve sheath diameter as a prognostic tool for postdural puncture headache in pregnant women undergoing caesarean section under spinal anesthesia: A cross-sectional study.

CONTEXT: Postdural puncture headache (PDPH) is a common and debilitating complication following spinal anesthesia in obstetric patients, with few objective tools available for early prediction. Optic nerve sheath diameter (ONSD) measured by ultrasonography is a noninvasive surrogate marker of intracranial pressure changes and may aid in early risk stratification.

AIM: To evaluate the prognostic utility of ONSD measurements in predicting PDPH among pregnant women undergoing cesarean section under spinal anesthesia.

MATERIALS AND

METHODS

This cross-sectional study included 88 pregnant women aged between 18 and 40 years undergoing cesarean section under spinal anesthesia. ONSD was measured using ultrasonography with a 13-6 MHz probe at baseline (T0) and at 4 (T4), 24 (T24), 48 (T48), and 72 h (T72) postprocedure. PDPH was diagnosed using International Classification of Headache Disorders criteria.

STATISTICAL ANALYSIS USED: Data were analyzed using SPSS version 22. Continuous variables were expressed as mean ± SD and categorical variables as frequencies and percentages. Student's t-test and Chi-square/Fischer's exact test were used as appropriate. Diagnostic performance was assessed using sensitivity, specificity, predictive values, and ROC curve analysis with calculation of area under the curve (AUC).

RESULTS

PDPH occurred in 12 patients (13.6%). Baseline ONSD values were comparable between groups. Patients who developed PDPH showed significantly lower ONSD values from T4 onward (P < 0.05). The best diagnostic performance was at T72 (AUC 0.776; 95% CI 0.663-0.889) with a cutoff ≤4.52 mm, yielding 91.7% sensitivity, 69.7% specificity, and 98.1% negative predictive value. ONSD reduction from baseline at T72 was significantly greater in the PDPH group (P < 0.001).

CONCLUSION

ONSD measurement at 72 h postspinal anesthesia is a sensitive and clinically useful prognostic tool for predicting PDPH in obstetric patients and may be incorporated into routine postoperative monitoring.