A 71-year-old woman presented to the neuro-ophthalmology clinic with worsening vision and difficulty with focus in the left eye. She had a history of sinonasal carcinoma diagnosed in 2000-2001 with resection via craniotomy and radiation. She had tumor recurrence in 2021 and underwent radiation therapy complicated by radiation-induced necrosis treated with bevacizumab. Recently, she had a diagnosed left orbital and middle cranial fossa meningioma. External examination of the left eye showed deep sulci and sunken appearance, reduced palpebral aperture, and rhythmic retrobulbar pulsation coinciding with vascular pulsation. Ophthalmic examination showed visual acuity 20/40 in each eye, rAPD of 0.6 log units in the left eye, and partial supero-temporal and inferonasal defects on visual field testing. She had nuclear cataract in both eyes, explaining the visual acuity. Dilated fundoscopic examination showed a flat disc with mild cupping without evidence of edema in the left eye and normal right eye. MRI and CT of the brain showed an absent left medial orbital wall, temporal lobe edema, and meningioma within the left orbit without effect on the optic nerve. CTA head/neck was without vascular abnormalities, notably without a CCF.

The ocular pulsation likely resulted from an absent protective barrier following the craniotomy, resulting in brain parenchyma and tissue moving with dynamic forces within the parenchyma and vascular blood supply. Temporal lobe edema and radiation-induced changes affecting orbital elastic forces further exacerbated this.  Additionally, the patient’s decreased vision was due to multiple factors including underlying nuclear cataracts, malignancy, left nasal orbital wall resection, and radiation. This case demonstrates the development of orbital pulsation following craniotomy and radiation, underscoring the importance of thorough neuro-ophthalmologic evaluation for effective management of complications.