The authors report a case of a 22-year-old otherwise healthy female who 
presented following a head injury during a bar altercation, with no associated 
loss of consciousness and an unknown mechanism of injury. Examination revealed 
an isolated 1cm laceration on the right upper eyelid, superior to her medial 
canthus. She experienced diplopia on right horizontal gaze due to a left 
internuclear ophthalmoplegia (INO) with an associated left conjugate horizontal 
gaze palsy, collectively described as a left one-and-a-half syndrome. CT and MRI 
demonstrated evidence of a deep penetrating injury above the right medial 
canthus, traversing the ethmoid and sphenoid sinuses, the dorsum sella, narrowly 
missing the basilar artery, penetrating the pons, and extending to the floor of 
the contralateral fourth ventricle. The patient was diagnosed with multiple 
sinus fractures, lesions in her left paramedian pontine reticular formation 
(PPRF) and medial longitudinal fasciculus (MLF), and progressive pneumocephalus. 
She underwent a transsphenoidal endoscopic repair via a vascularized mucosal 
flap without complication. Postoperatively, the patient's pneumocephalus 
resolved and her conjugate gaze markedly improved; however, minimal diplopia 
remained. This case demonstrates the importance of the clinical exam, and its 
benefit in localizing imaging findings and guiding treatment.