Neurology Case Presentation MARCH 23 2012 LORI NOOROLLAH

Neurology Case Presentation MARCH 23, 2012 LORI NOOROLLAH

Chief Complaint �Double Vision �HPI: Middle aged woman who reports that she woke up with blurry vision and pain in her right eye Two week later– woke up with double vision � Binocular, vertical and horizontal � Worse on right gaze Three months later– woke up with blurry vision in left eye and left orbital pain

More History �PMH: HTN, Anxiety, chronic pain, GI bleed due to diverticulosis �Meds: Clonidine 0. 2 mg q. HS Metoprolol 50 mg BID Diazepam prn Diltiazem q. AM Losartan 100 mg q. HS hydrocodone prn �SH: Smokes 3 -4 cigarettes daily for 25 years No Et. OH or illicit drug use

General Exam �Alert, oriented, no acute distress �CV: RRR, no carotid bruit �Chest: CTAB �Visual Acuity: OD: 20/60 OS: 20/25 �+relative APD on right �red-green dyschromatopsia on right

Neurological Exam �Mental status and speech normal �CN: PERRL APD on right Visual Fields – � Inferior arcuate defect on Right � Enlarged blind spot on Left normal facial sensation and movement, symmetric palate elevation, tongue midline EOM: Limited abduction and slightly limited upgaze bilaterally �Motor, Sensory, Reflexes, Coordination – within normal limits

Visual Fields Inferior arcuate defect in right eye Enlarged blind spot in left eye

? Where? ? What?

Differential Diagnosis �Anterior Ischemic Optic Neuropathy (AION) + cranial nerve infarcts AAION vs. NAION �Optic Neuritis �Ocular Myasthenia gravis Acetylcholine receptor antibodies negative

NAION Non-arteritic Anterior Ischemic Optic Neuropathy is an “idiopathic” ischemic insult of the optic nerve head �Most common optic neuropathy Annual incidence for people > age 50 is 2. 3 – 10. 2 /100, 000 95% of cases occur in Caucasian population

NAION � Clinical presentation: Sudden monocular visual loss Blurring or cloudiness Often noticed upon awakening (73%) Most often painless � � 12% have ocular pain or headache A lot of pain more suggestive of optic neuritis or AION � Exam: Reduced visual acuity to varying degrees � Dyschromatopsia proportional to reduction in visual acuity Afferent pupillary defect Fundoscopic Exam: � � � Not ruled out by normal visual acuity Optic disc swelling Disc hyperemia with splinter or flame hemorrhages Small optic cup (nerve fiber crowding) in unaffected eye Visual field defect – relative inferior altitudinal defect and absolute inferior nasal defect

NAION – Fundoscopic Exam Hayreh SS (2009) Ischemic optic neuropathy. Progress in retinal and eye research 28: 34 -62

NAION �Vascular supply to optic nerve head 15 -20 short posterior ciliary arteries, supplied by ophthalmic artery

NAION �Pathogenesis: Different than Ischemic CVA � No clear relationship with HTN, HLD, smoking � Not associated with embolism or large vessel occlusion Transient hypoperfusion of posterior ciliary arteries � Vasospasm vs. nocturnal hypotension vs. impaired autoregulation of microvasculature vs. vasculopathic occlusion vs. venous insufficiency Hypoxia/Ischemia optic disc swelling (in setting of physiologically crowded optic nerve head) infarction �Treatment = Modify risk factors, vision therapy Early therapy shown to have better recovery Questionable role for steroids

NAION and OSA �Nocturnal Hypotension Normal physiologic occurrence Autoregulation �OSA Loss of autoregulation Non-dipping status Hypoxic-ischemic insult to optic nerve head �Anti-hypertensive medications at night may also disrupt autoregulation

OSA and NAION �Stein, 2011 – American Journal of Ophthalmology �Retrospective cohort study Review from managed care database looking at patients > 40 with at least 1 eye-care visit N=2, 259, 061 Compared incidence of NAION in population with and without OSA � Compared NAION in treated vs. untreated OSA

OSA and NAION �Results: �After adjusting for confouding variables: Untreated OSA patients had 16% increased hazard of experiencing NAION (HR 1. 16, CI 1. 01 -1. 33) compared with non-OSA patietns Treated OSA patients had no difference in hazard (HR 1. 38, CI 0. 76 -2. 5) compared with non-OSA patients

NAION – Future Studies �Implications: Do patients with NAION need screening for OSA? Do patients with OSA need evaluation? Consider avoiding anti-hypertensive medications at night, especially in patients “at risk” for NAION �Future Studies: Treatment options/Intervention/Prevention Further investigation into the pathophysiology of NAION

References � Anterior Ischemic Optic Neuropathy: Part II: a discussion for physicians. Sohan Singh � � � Hayreh, MD, MS, Ph. D, DSc, FRCS, FRCOphth http: //webeye. ophth. uiowa. edu/component/content/article/118 -aion-part 2 Atkins, EJ Nonarteritic Anterior Ischemic Optic Neuropathy. Current Treatment Options in Neurology. 2011; 13: 92 -100 Hayreh SS (2009) Ischemic optic neuropathy. Progress in retinal and eye research 28: 34 -62 Kerr NM, Etal. Non-arteritic ischaemic optic neuropathy: A review and update. Journal of Clinical Neuroscience. 2009; 16: 994 -1000. Stein JD, Etal. The Association between Glaucomatous and other causes of Optic Neuropathy and Sleep Apnea. Am J Ophthalmol. 2011; 152: 989 -998. Up To Date Online