Evaluating Ex Vivo Fluorescence Confocal Microscopy for Intraoperative Diagnosis in Pediatric Surgery: A Feasibility Study

Background: Ex vivo fluorescence confocal microscopy (FCM) is an emerging technology that enables real-time, high-resolution digital imaging of freshly excised tissues without requiring standard histological preparation. This study aims to evaluate the diagnostic performance of FCM compared to conventional histology in a pediatric population with suspected oncological pathology. Materials and methods: A total of 18 tissue samples from pediatric patients with suspected oncological lesions were analyzed using FCM. The results were compared to the definitive diagnoses obtained via conventional histology, serving as the gold standard. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated to assess the diagnostic accuracy. Cohen's kappa coefficient (K), 95% confidence interval (95%CI) and p-value were computed to evaluate the interobserver agreement and the concordance between FCM and histology. Results: FCM correctly identified 10 positive cases (true positives) and 7 negative cases (true negatives), with 1 false positive and no false negatives. Interobserver agreement was perfect, with a Cohen's kappa coefficient of 1.00 (95% CI: 0.81-1.00, p < 0.001). Sensitivity was 100% (95% CI: 72.2%-100%), specificity 87.5% (95% CI: 52.9%-97.8%), PPV 90.9% (95% CI: 62.3%-98.4%), and NPV 100% (95% CI: 64.6%-100%). The Cohen's kappa coefficient was 0.89, indicating excellent agreement between FCM and histology (95% CI: 0.67-1.10, p < 0.001). FCM provided rapid diagnostic results, significantly reducing turnaround time compared to conventional methods. Conclusions: FCM demonstrates exceptional diagnostic accuracy, with excellent sensitivity and specificity in evaluating pediatric specimens. Its ability to deliver reliable intraoperative results highlights its potential as a valuable adjunct to conventional histopathology in pediatric surgery. Larger studies are warranted to confirm these findings and establish its role in clinical practice.