The trigeminal nerve has the largest territory of sensory innervation across the head and neck. It leaves the lateral pons through a large lateral sensory and small medial motor root. Root Entry Zone is an anatomical landmark of great functional hierarchy where variants in nervous tract trajectories and arterial loops, may result in neurovascular conflicts leading to neuralgias. The sensory root holds clinical significance because it innervates sensory receptors of the head and neck. This case reports a cadaveric brain stem with significant loss/ hypotrophy of left trigerminal nerve fibers. Such forfeit (weather due to congenital hypotrophy or postnatal lesion) can lead to variable degree of sensory loss along the nerve course and the innervation of mastication apparatus, change in of cerebellopontine angel and cistern volumes. The clinical outcomes of missing fibers might be not only hold symptomatic indicators for neurosurgeons but also morphologic benchmarks for biological anthropologists. These incidental findings are noteworthy to understand the causes, intricacies and clinical consequences of such neuroscience dilemmas. The case reported here might have presented with perplexing neurosensory ambiguities while alive and leaves ground of speculation for anatomists and neurologists. It is fundamental to identify spatial relations between different portions of the nervous tract, (especially while establishing possible vascular contact conflicts) that could explain lesser known Trigerminus syndromes. In future, high spatial resolution imaging would allow the study of each portion of the trigeminal nerve, recognizing with more clarity the anatomical variants or pathological elements.
