A 66-year-old Hispanic woman presented to the eye clinic with chronic, progressively worsening vision in the right eye over 2 years associated with right-sided temporal headaches, cutaneous allodynia of the scalp, and jaw claudication. She denied fevers, chills, joint pains, nausea, photophobia, phonophobia, personal history of autoimmune disease, and family history of hereditary ophthalmological diseases. Her ocular history included pterygium removal from the OD. Seven years prior to presentation, she had an episode of light-headedness, blurry vision for 30 minutes, a severe headache, and mild weakness of the left hemiface and left body lasting 2 hours. She was evaluated by her primary care provider, the emergency department, and neurology; neuroimaging was recommended but never completed, and atypical migraine was considered.
At this presentation, her best corrected visual acuity was 20/400 OD and 20/20 OS. She had a 2+ relative afferent pupillary defect OD and optic disc pallor in the right eye with optic atrophy seen on magnetic resonance imaging of the brain and orbits. Fundoscopy of the left eye was normal. Automated perimetry showed visual field defects in each eye (Fig. 1). Erythrocyte sedimentation rate, C-reactive protein, and platelets were within normal limits. Computerized tomography angiography (CTA) was performed along with 3-dimensional volume-rendered CTA reformatting and angiography (Fig. 2), which demonstrated poor perfusion through the right supraclinoid segment of the internal carotid artery that was confirmed with angiography, leading to the diagnosis of moyamoya disease (MMD). Neurosurgery evaluated the patient and determined that the risks for undergoing an external carotid-internal carotid bypass outweighed the benefits at this time.
Fig. 1Visual field demonstrates junctional scotoma; 24-2 Humphrey visual field showed decreased sensitivity more temporally in the left eye and a central defect breaking out temporally in the right eye.
Fig. 2Computerized tomography angiography (CTA) and angiography with stenotic internal carotid artery (ICA); axial (A), coronal (B) CTA maximum intensity projection images; 3-dimensional volume-rendered CTA reformat (C); and AP projections from right (D) and left (E) selective ICA injections from a digital subtraction angiogram demonstrate an occluded right supraclinoid ICA (blue arrow) and small caliber right middle cerebral artery (green arrow) compared to the patent contralateral left supraclinoid ICA at the carotid terminus (red arrow) and normal caliber left Middle cerebral artery (MCA) (purple arrow).
Discussion
MMD and moyamoya syndrome (MMS) are characterized by a diffuse narrowing of the internal carotid, middle cerebral, or anterior cerebral artery lumen.
1
The fine tangle of compensatory collateral vessels produces the distinctive cranial angiography. (Moyamoya is Japanese for “puff of smoke.”) The classic patient is a young woman of Asian descent with a family history of medical issues similar to those demonstrated by our patient: temporal headache, jaw claudication, and progressive vision loss.Etiologies for MMD and MMS include idiopathic, iatrogenic (i.e., radiation), atherosclerosis, and congenital. Twelve percent of cases are familial, and the disease has been associated with several polymorphisms of the RNF213 gene, which encodes a gene finger protein.
2
Although MMD and MMS are rare, this life-threatening disease is important to keep in the differential when a patient presents with ipsilateral optic atrophy.Poor perfusion may result in optic nerve ischemia, which can result in the “morning glory disc” anomaly as the optic nerve develops. This finding is characterized by chorioretinal pigment changes surrounding the optic disc, an enlarged and funnel-shaped appearance of the optic disc, and central tuft of glia in the center of the optic disc.
3
Our patient is notable for the involvement of the optic chiasm, resulting in a junctional scotoma—a description that we have not seen to date in the English literature.Medical management involves antiplatelet treatment, although the evidence supporting this practice is limited. Surgical revascularization is offered as well and is often pursued in pediatric patients who are more likely to have the progressive form of the disease.
4
Revascularization can be either direct or indirect. Direct involves anastomoses created between the superficial temporal artery and the middle cerebral artery. Indirect involves the use of implanted vascular tissue to promote angiogenesis in the implanted area.5
Footnotes and Disclosure
The authors have no proprietary or commercial interest in any materials discussed in this article.
References
- Moyamoya disease: a review of clinical research.Acta Med Okayama. 2016; 70: 229-236
- RNF213 polymorphism and Moyamoya disease: a systematic review and meta-analysis.Neurol India. 2013; 61: 35-39
- Morning glory syndrome with Moyamoya disease: a rare association with role of imaging.Indian J Radiol Imaging. 2018; 28: 165-168
- Indirect revascularization surgery for moyamoya disease in children and its special considerations.Korean J Pediatr. 2012; 55: 408-413
- Moyamoya disease.Neuropatho. 2000; 20: S61-S64
Article Info
Publication History
Published online: February 01, 2021
Accepted:
January 11,
2021
Received in revised form:
November 6,
2020
Received:
July 6,
2020
Identification
Copyright
© 2021 Canadian Ophthalmological Society. Published by Elsevier Inc. All rights reserved.
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