Vertical Diplopia and Ptosis from Removal of the Orbital Roof in Pterional Craniotomy

Abstract

Purpose To describe a newly recognized clinical syndrome consisting of ptosis, diplopia, vertical gaze limitation, and abduction weakness that can occur following orbital roof removal during orbito-zygomatic-pterional craniotomy. Design Case series. Participants Eight study patients, ages 44 – 80 years, 7 female, with neuro-ophthalmic symptoms after pterional craniotomy. Methods Case description of eight study patients. Main Outcome Measures Presence of ptosis, diplopia, and gaze limitation. Results Eight patients had neuro-ophthalmic findings after pterional craniotomy for meningioma removal or aneurysm clipping. The cardinal features were ptosis, limited elevation and hypotropia. Three patients also had limitation of downgaze and two had limitation of abduction. Imaging showed loss of the fat layers which normally envelop the superior rectus/levator palpebrae superioris. The muscles appeared attached to the defect in the orbital roof. Ptosis and diplopia developed in two patients despite Medpor titanium mesh implants. Deficits in all patients showed spontaneous improvement. In two patients a levator advancement was required to repair ptosis. In three patients an inferior rectus recession using an adjustable suture was performed to treat vertical diplopia. Follow-up a mean of 6.5 years later revealed that all patients had a slight residual upgaze deficit, but alignment was orthotropic in primary gaze. Conclusions After pterional craniotomy, ptosis, diplopia and vertical gaze limitation can result from tethering of the superior rectus/levator palpebrae superioris complex to the surgical defect in the orbital roof. Lateral rectus function is sometimes compromised by muscle attachment to the lateral orbital osteotomy. This syndrome occurs in about 1% of patients after removal of the orbital roof and can be treated, if necessary, by prism glasses or surgery.

Restrictive Strabismus Following Frontotemporal-orbitozygomatic Craniotomy

“…Moreover, the muscle can be prone to mechanical restriction from alterations in the bony anatomy and/or implant placed for reconstruction that result in a step-off or ridge as demonstrated in this series. Desai, et al also did report adhesion of the lateral rectus muscle to the osteotomy following lateral wall removal, further supporting the significance of the surgical anatomy in this complication [ 5 ].…”

“…Although neurosurgical access to SWMs has improved with the FTOZ approach, ophthalmologic risks associated with resection and reconstruction of the roof and lateral wall of the orbit include enophthalmos, vision loss, ocular misalignment, and diplopia. Earlier studies attributed extraocular muscle restriction to physical injury of the muscle or respective cranial nerve during surgery, postoperative edema, and soft-tissue adhesion to the lateral wall osteotomy [ 3 - 5 ]. Liu, et al reported limitation of extraocular muscle in 40.5% (15/37) of patients after a pterional approach, which was transient in nature in 73.3% of cases and attributed to excessive traction during surgery [ 4 ].…”

“…Both patients had limited adduction with a corresponding exotropia in primary gaze and a positive forced duction test (FDT) postoperatively. Vertical diplopia following craniotomy via a pterional approach has also been observed [ 5 - 7 ]. In a series by Desai, et al, the proposed mechanism was adhesion of the extraocular muscle to the orbital roof, reducing its ability to rotate the globe [ 5 ].…”

“…Vertical diplopia following craniotomy via a pterional approach has also been observed [ 5 - 7 ]. In a series by Desai, et al, the proposed mechanism was adhesion of the extraocular muscle to the orbital roof, reducing its ability to rotate the globe [ 5 ]. Similarly, Kaeser and Klainguti attributed vertical diplopia to the adhesion of the superior rectus/levator palpebrae complex to the orbital roof [ 7 ].…”

Orbito-Masticatory Syndrome

“…Reported neuro-ophthalmic complications in the setting of orbitozygomatic and fronto-temporal craniotomy include cosmetic deformity, enophthalmos, pulsatile exophthalmos, ptosis, diplopia, vertical gaze limitations and blindness (10, 11). Poor cosmetic and structural outcomes often stem from suboptimal reconstruction of a defect in the temporal region (12) and we add masticatory proptosis and oscillopsia to the list of complications.…”