Related Experiment Video
Updated: Aug 13, 2026

In Vivo Calcium Imaging of Neuronal Ensembles in Networks of Primary Sensory Neurons in Intact Trigeminal Ganglia
Published on: August 1, 2025
Unilateral hypoplasia of the trigeminal ganglion
Andrew D Milne1, Lica Chui, Aditya V Mishra
1Department of Anesthesia, Dalhousie University, Halifax, NS.
Case Report:
We report a case of unilateral anaesthesia of the V1 (ophthalmic) division of the trigeminal cranial nerve presenting with persistent corneal erosions and ulceration secondary to trigeminal ganglion hypoplasia. The patient had a lifelong history of unexplained left-sided ophthalmic symptoms for which numerous diagnoses were provided. Cranial nerve testing demonstrated partial trigeminal dysfunction on the left side. Further investigation eliminated viral etiologies, and subsequent magnetic resonance imaging determined that the patient had a hypo-plastic left trigeminal ganglion.
Comments:
We present the case to alert clinicians to the possibility of this rare condition.
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