Post-craniotomy blindness in the supine position: Unlikely or ignored?
A 37-year-old female patient presented with a 5 months history of constant pulsatile frontal headache. The headaches were only somewhat responsive to paracetamol but she had to take narcotics to get to sleep. Recently, she had noticed that she was unable to distinguish smells while cooking and the food had a different taste for her.\nNeurological exam revealed anosmia and bilateral papilledema more severe on the left side. Visual acuity was 20/20 and 20/40 in the right and left eyes, respectively. The remainder of the physical exam and the laboratory tests were all within normal range.\nAxial brain CT scan was performed and demonstrated an extra axial hyperdense interhemispheric space-occupying lesion within the anterior cranial fossa. Surrounding vasogenic edema was evident. Brain magnetic resonance imaging (MRI) with and without contrast revealed the mass that was isointense relative to the gray matter on T1 and T2-weighted images. The tumor showed a homogenous contrast uptake with gadolinium injection suggesting anolfactory meningioma [].\nThe patient was operated in the supine position and the head was placed in the neutral position. A bifrontal craniotomy was performed over the superior sagittal sinus (SSS). The dura was opened in a linear fashion on both sides of SSS and it was ligated at its anterior third. Gross total resection of the firm tumor was made, the infiltrated dura was resected and the tumor's adhesions to the anterior skull base were coagulated (Simpson grade II).\nThe patient awoke with sudden bilateral blindness. Her vision was no light perception (NLP) in both eyes. Extraocular movement and IOP were normal. Fundoscopy revealed no apparent change. The anesthesiologist records documented no intra-operative hypotension. Early axial brain CT scan excluded the possibility of developing mass effect and 24 h brain MRI showed no residual tumor. One main concern was the possibility of inadvertent surgical trauma to the optic nerves or chiasm. Review of the operative video excluded this possibility, as well as any external pressure on the eyes during the surgery. Visual evoked potential (VEP) responses were completely abolished in both eyes.\nSerial therapeutic lumbar punctures (LP) were done and high dose methylprednisolone were given for three days with the hope to resolve possible optic nerve entrapment, which was unsuccessful. After six weeks post-procedure, she gained some light perception in her right eye. Follow-up fudoscopy revealed bilateral optic disc atrophy after two months. During 52 months follow up, her visual status showed no improvement. Fundoscopy revealed bilateral optic atrophy [].\nInformed consent was sought and granted from the patient's family to report this case.