Cavernous Venous Malformation of the Inferior Orbital Fissure and Pterygopalatine Fossa: A Case Report

A62-year-old woman presented to our neuro-ophthalmology clinic in referral from her comprehensive ophthalmologist. Past medical and ocular history included diverticulosis, depression, and early nonexudative age-related macular degeneration, which had been diagnosed approximately 1 year before presentation.

Clinical Correspondence Section Editors: Robert Avery, DO Karl C. Golnik, MD Caroline Froment, MD, PhD An-Guor Wang, MD Cavernous Venous Malformation of the Inferior Orbital Fissure and Pterygopalatine Fossa: A Case Report Margaret S. Powell, MD, Eric L. Berman, MD CASE REPORT A 62-year-old woman presented to our neuroophthalmology clinic in referral from her comprehensive ophthalmologist. Past medical and ocular history included diverticulosis, depression, and early nonexudative age-related macular degeneration, which had been diagnosed approximately 1 year before presentation. She endorsed “dimmer” vision on the left compared with the right for the past year. For the past 6 months, she had noticed slowly progressive “blind spots” in her vision in the left eye, which she noted with routine Amsler grid monitoring. Initial exam in our clinic demonstrated mildly decreased visual acuity on the left, full extraocular movements bilaterally, and mild left optic disc pallor. A 0.6 log unit relative afferent pupillary defect (RAPD) was noted. Ancillary testing included Humphrey 30-2 visual field testing which revealed full visual fields on the right and relatively nonspecific changes in the left eye, and optical coherence tomography (OCT) of both macula and optic nerves. The retinal ganglion cell layer thickness was normal bilaterally, with mild temporal circumpapillary thinning in 2 clock-hours on the left eye. MRI revealed a T2-hyperintense, heterogeneously enhancing, 1.5- · 1-cm extraconal mass of the left orbital apex which extended through the inferior orbital fissure and into the pterygopalatine fossa (Fig. 1). The left optic nerve was displaced superiorly with compression against the roof of the optic canal. Computed tomography of the orbit was obtained which demonstrated homogeneous hyperintensity of the mass with associated bony remodeling of the inferior orbital fissure and medial orbital wall (Fig. 2). FIG. 1. Pre-operative T2 sagittal MRI demonstrating extension of the lesion from pterygopalatine fossa up through inferior orbital fissure to orbital apex. Department of Ophthalmology, Storm Eye Institute, Medical University of South Carolina, Charleston, South Carolina. The authors report no conflicts of interest. Address correspondence to Margaret S. Powell, MD, Storm Eye Institute, 171 Ashley Avenue, Charleston, SC 29425; E-mail: [e-mail] Powell and Berman: J Neuro-Ophthalmol 2022; 42: e387-e388 FIG. 2. Pre-operative coronal CT scan showing bony remodeling of the inferior orbital fissure and medial orbital wall. e387 Copyright © North American Neuro-Ophthalmology Society. Unauthorized reproduction of this article is prohibited. Clinical Correspondence An endoscopic approach through the maxillary and sphenoid sinuses was deemed preferable to an orbital approach due to the lesion’s apical location. The patient underwent mass resection approximately one month after initial presentation to our center, performed jointly by neurosurgery and otolaryngology services. Orbital apex access was obtained via binasal endonasal endoscopic approach, and the lesion was removed in its entirety within a fibrous capsule and sent to pathology for analysis. Histology of the lesion was consistent with cavernous venous malformation. The patient reported immediate subjective improvement of visual symptoms postoperatively. At evaluation, 1-month postoperatively, she had residual RAPD and mild nerve pallor, but her acuity and visual fields had normalized and she continued to endorse subjective visual improvement. Cavernous venous malformations are vascular lesions of abnormally dilated blood vessels, and have been described in multiple tissues, including orbit, brain, skin, liver, and bone. Histologic evaluation demonstrates multiple dilated endothelial-lined vascular channels separated by stromal septa. Although often described as hemangiomas, the growth process is more consistent with budding neovascularization than a neoplastic cell proliferation (1). If asymptomatic, they may be observed, as lesion growth is slow. Most symptomatic patients are middle-aged, with women more frequently affected than men. Familial inheritance has been described, although the genetics are incompletely understood. Visual symptoms stem from mass effect on posterior globe, extraocular muscles or optic nerve, depending on the location of the lesion within the orbit. The large size of our patient’s lesion with relatively recent onset of visual symptoms suggests growth over a long period with likely inferior origin in the pterygopalatine fossa and growth superiorly through the fissure to involve the orbital apex structures. Symmetrically intact ganglion cell layer thickness on OCT and complete reversal of visual symptoms after lesion removal in our patient also support relatively late compression of the optic nerve. Differential diagnosis of a lesion in the pterygopalatine fossa is broad and includes schwannoma, neurofibroma, vascular malformation, hemangiopericytoma, meningioma, lymphoma, angiofibroma, sinonasal carcinoma, metastatic disease, epidermoid cyst, or teratoma, in addition to inflammatory or infectious processes (2). The location of this lesion in the inferior orbital fissure and pterygopalatine fossa is unusual, as cavernous venous malformations of the nasal cavities and sinuses are much less common than in the orbit or CNS. Upon literature review, we found only 2 other case reports of cavernous venous malformation in the pterygopalatine fossa. Sahin et al report a cavernous venous malformation of the pterygopalatine fossa without apparent impingement on orbital apex structures (3). A cavernous e388 venous malformation extending from left orbital apex to pterygopalatine fossa was described by Yoshimura et al, which presented with visual field defect of the left eye (4). Harris et al present a series of orbital apex cases, all of which manifest with visual acuity and visual field changes (1). A review by Rootman et al found that of 39 cases evaluated over 10 years, 4 (10.4%) involved the inferior orbital fissure, although no comment was made on inferior extension into the pterygopalatine fossa (5). Lesions involving the orbital apex structures, including superior or inferior orbital fissure or optic canal, were more likely to be associated with a compressive optic neuropathy and corresponding relative afferent pupillary defect, decreased visual acuity, and/or visual field changes. Although in this review and throughout the literature, the most common overall presenting sign is axial proptosis, this was not seen in our case because of the posterior and extraconal location of the lesion. To our knowledge, this case is one of very few in the literature reporting cavernous venous malformation of the pterygopalatine fossa. In addition, our case may be unique in that the lesion likely originated in the pterygopalatine fossa with secondary extension into the orbital apex and visual compromise. Complete surgical excision was achieved with subsequent restoration of visual acuity and resolution of visual field abnormalities. STATEMENT OF AUTHORSHIP Category 1: a. Conception and design: M. S. Powell and E. L. Berman; b. Acquisition of data: M. S. Powell and E. L. Berman; c. Analysis and interpretation of data: M. S. Powell and E. L. Berman. Category 2: a. Drafting the manuscript: M. S. Powell and E. L. Berman; b. Revising it for intellectual content: M. S. Powell and E. L. Berman. Category 3: a. Final approval of the completed manuscript: M. S. Powell and Eric L. Berman. REFERENCES 1. Harris GJ. Cavernous venous malformation of the orbital apex: pathogenetic considerations in surgical management. Am J Ophthalmol. 2010;150:764–773. 2. Tashi S, Purohit BS, Becker M, Mundada P. The pterygopalatine fossa: imaging anatomy, communications, and pathology revisited. Insights Imaging. 2016;7:589–599. 3. Şahin B, Sönmez S, Yılmazbayhan ED, Orhan KS. Cavernous venous malformation in unusual location: pterygopalatine fossa. Braz J Otorhinolaryngol. 2016;85:121–124. 4. Yoshimura KK, Kubo S, Yoneda H, Tominaga S, Yoshimine T. Removal of a cavernous venous malformation in the orbital apex via the endoscopic transnasal approach: a case report. Minim Invas Neurosurg. 2010;53:77–79. 5. Rootman DB, Heran MK, Rootman J, White VA, Luemsanran P, Yucel YH. Cavernous venous malformations of the orbit (socalled cavernous haemangioma): a comprehensive evaluation of their clinical, imaging and histologic nature. Br J Ophthalmol. 2014;98:880–888. Powell and Berman: J Neuro-Ophthalmol 2022; 42: e387-e388 Copyright © North American Neuro-Ophthalmology Society. Unauthorized reproduction of this article is prohibited.