Approach to a patient with bilateral vision loss

bilateral vision loss

1. Approach to a patient with bilateral vision loss Dr. Nishtha Jain Senior Resident Department of Neurology GMC, Kota.

2. Question 1 Patient with visual loss Monocular Binocular

3. Question 2 Patient with Bilateral visual loss Transient Persistent

4. Persistent bilateral visual loss Both anterior visual visual pathways Both optic Nerves Chiasmal involvement Retrochiasmal involvement

5. Question 3 Patient with persistent bilateral visual loss Non progressive Progressive

6. Age of presentation Associated neurological symptoms Risk factors Family history Any particular sector of visual field affected Associated visual symptoms Additional History

7. A child coming with persistent non progressive bilateral visual loss

8. Ophthalmologic conditions Anophthalmos and microphthalmos Persistent hyperplastic primary vitreous Infantile glaucoma Retinal dystrophies Congenital Cataract Retinopathy of prematurity

9. Congenital Tilted Disc Syndrome 1% to 2% of the population. The disc is tilted in an inferonasal direction. Bilateral in 80% of patients Result in myopia and astigmatism. Also cause bitemporal hemianopic field defects that can mimic those seen in chiasmal lesions but defect crosses the midline(not observed with chiasmal hemianopias ).

10. Optic Nerve Coloboma Caused by incomplete closure of the embryonic fissure. May occur sporadically. In bilateral cases with systemic involvement, inherited in an autosomal dominant pattern. Clinical findings- visual field defects and decreased visual acuity.

11. An enlarged, sharply circumscribed, glistening disc with a deeply excavated inferior border. With time, serous macular detachment may occur.

12. Morning Glory Disc Anomaly A variant of optic disc coloboma . More common in females Result of posterior displacement of the nerve and peripapillary retina Due to incomplete closure of the fetal fissure. Retinal detachment (typically involving only the posterior pole) may result.

13. Optic Nerve Hypoplasia Most common congenital optic disc anomaly. Bilateral in 56% to 92% of patients. Localized (typically arcuate and peripheral) visual field loss is common. Defective chiasm/midline development resulting in retrograde degeneration or defective differentiation of ganglion cells. Proposed risk factors - young maternal age, first parity, maternal smoking, preterm birth, and the use of fertility drugs and antidepressant medications.

14. Superior segmental optic nerve hypoplasia , is characterized by selective involvement of the superior portion of the optic nerve head, resulting in a ‘‘topless optic nerve.’’ Almost exclusively seen in children of diabetic mothers. The triad of optic nerve hypoplasia , absence of the septum pellucidum , and hypopituitarism is termed septo- optic dysplasia (de Morsier syndrome). MRI is recommended for all children presenting with optic nerve hypoplasia .

15. The optic disc is small in diameter(one-half to one-third of normal size). The nerve may be pale in color and surrounded by a yellowish peripapillary halo circumscribed by a darker ring of pigment (double-ring sign).

16. Middle/old age person with bilateral sequential/simultaneous non progressive visual loss

17. Optic disc is swollen Visual field loss is typically inferior altitudinal Risk factors - systemic hypertension, diabetes mellitus, hypercholesterolaemia Non arteritic anterior ischemic optic neuropathy

18. Visual acuity spontaneously improves in over 40% by six months but without improvement in the visual field loss. The optic disc swelling resolves to leave optic disc pallor, often segmental. Does not recur in the same eye but there is about 15% risk of fellow eye involvement. Low dose aspirin reduce this risk and is usually recommended, together with control of risk factors amenable to treatment.

19. Associated with Jaw Claudication , polymyalgia rheumatica and constitutional symptoms Tenderness or absence of pulsation of the superficial temporal arteries Fundus shows optic neuropathy with central retinal artery occlusion Arteritic anterior ischemic optic neuropathy

20. Erythrocyte sedimentation rate (ESR) and C reactive protein (CRP) are usually raised. Temporal artery biopsy - with a specimen of at least 2 cm in length. Emergency systemic steroid treatment. Standard initial treatment is oral prednisolone (1–1.5 mg/kg/day).

21. Sudden onset of headache, decreased acuity and/or visual field loss, altered mental status, and hormone dysfunction Visual field defect -superior bitemporal quadrantanopia Pitutary Apoplexy

22. Age - 37 to 57 years Male-to-female predominance of 2:1. Lumbar puncture may disclose elevated opening pressure, pleocytosis , increased red blood cells, and xanthochromia . MRI is the imaging study of choice.

23. Stroke

24. Persistent Progressive Bilateral Visual Loss

25. Causes of Retinopathy Diabetes Mellitus Hypertension Atherosclerosis Systemic vasculitis Blood dyscrasias Systemic infections Radiation

26. Fundus Autofluorescence imaging Metabolic mapping of naturally and pathologically occuring flurophores of ocular fundus . Flouroscence is mainly derived from lipofuscin . Uses : Cystoid macular oedema, wet AMD, Choroidal neovascularisation, Diabetic macular oedema

27. Optical Coherence Tomography Noninvasive imaging technique Provides high-resolution, cross-sectional images of the retina, retinal nerve fiber layer and the optic nerve head. Time-domain detection- 400 A-scans per second with an axial resolution of 8–10 μm in tissue. Spectral domain (Fourier domain) – 20000–52000 A-scans per second and a resolution of 5–7 μm in tissue .

28. Ultra high-resolution OCT - achieve 3 μ m resolution in tissue. Swept-source OCT - the interference spectrum is measured by photodetectors instead of a spectrometer. Used in - Age-related macular degeneration, central serous chorioretinopathy , polyploidal choroidal vasculopathy , Diabetic retinopathy, inherited retinal dystrophies

29. Optic Neuropathy Classic features of an optic neuropathy: (1) central visual loss, (2) clear view through the ocular media to the optic nerve, (3)a swollen or pale optic nerve head.

30. Autosomal Dominant Optic Atrophy Also K/A Kjer optic atrophy. Characterized by decreased acuity, dyschromatopsia , abnormal visual fields (often central or cecocentral scotomas ), and optic nerve pallor in the papillomacular bundle. Approximately the time children reach school age. Bilateral visual loss is the rule, but may be asymmetric.

31. Insidious progression of visual loss, but typically not past the second decade of life. Tritanopia (an inability to distinguish between colors in the blue green section of the spectrum) is the classic pattern of color loss in patients with dominant optic atrophy.

32. Leber Hereditary Optic Neuropathy Maternally inherited condition. Result in degeneration of the retinal ganglion cells and their axons. Young males are most commonly affected Typical clinical course - acute visual loss in one eye, followed weeks to months later by visual loss in the fellow eye. More than 97%of patients - involvement in the second eye within 1 year.

33. Visual acuity is variable - 20/200 or worse. Significant loss of color vision. Central visual field defects. Three mitochondrial DNA point mutations : 11778 (69% of cases), 3460 (13% of cases), and 14484 (14% of cases). 14484 mutation - better visual acuities and better rates of spontaneous recovery than patients with other mutations.

34. Funduscopic examination circumpapillary telangiectatic microangiopathy , swelling of the nerve fiber layer around the disc ( pseudoedema )and absence of leakage from the disk or peripapillary region on fluorescein angiography.

35. Toxic Optic Neuropathy Portions of the anterior visual pathway (optic nerve, retina, and chiasm) are susceptible to direct damage from toxins or indirect damage from nutritional deficiency states. Affect both eyes due to the systemic pathophysiology . A detailed history, including medications and habits, must be obtained.

36. In patients with bilateral visual loss, serum B12, folate levels, vitamin assays, complete blood count, blood chemistries, urinalysis, and a serum lead level (if appropriate) may be useful in identifying the underlying cause. Treatment is focused on removal of the offending agent, repletion of deficient vitamins, and improving nutrition status.

37. Common Causes

38. Glaucomatous Optic Neuropathy

39. Sellar Mass Gradually progressive visual loss, particularly if associated with endocrine dysfunction. The classic visual field defect is the bitemporal hemianopia . Other examination features of chiasmal visual field loss include postfixation blindness. Mass or trauma involving the chiasm can result in seesaw nystagmus .

40. In children commonly include chiasmal / hypothalamic glioma and craniopharyngioma . In adults, pituitary adenoma is the most common. Of the secreting adenomas, prolactin secreting tumors are the most common. Corticotropin -secreting pituitary tumors are seen most commonly in women during childbearing years.

41. Managed by transsphenoidal neurosurgery. Prolactin -secreting tumors can be treated with dopamine agonists. In up to 80% of patients, gradual titration of bromocriptine to a dose of 2.5 mg to 5 mg 3 times a day can successfully reduce tumor size.

42. ANEURYSM Common aneurysm locations resulting in chiasmal defects include the supraclinoid internal carotid artery, the junction between the carotid and ophthalmic artery, and, less commonly, the cavernous or anterior communicating arteries. Neurosurgical clipping, when possible, is preferable to endovascular embolization .

43. Transient Binocular Visual Loss

44. Transient Binocular Visual Loss

45. TIAs TIAs cause a sudden onset of homonymous binocular TVL. Can result from primary arterial stenosis or occlusion, secondary occlusion due to embolism from a distant source, or, less commonly, from arterial dissection. Infrequent causes of posterior circulation TIAs include subclavian steal syndrome and ‘‘bow-hunter’’ syndrome.

46. Very rarely, giant cell arteritis (GCA) can cause isolated vertebral arteritis and without producing any of the other characteristic symptoms. The neurologic and ophthalmic examinations are usually normal between TIAs. Abnormalities on cardiovascular examination .

47. Imaging of the intracranial and extracranial (head and neck) vessels using Doppler ultrasound and CT or MR/catheter angiography should be obtained. If dissection is suspected, fat-saturated T1-weighted images of the head and neck should be obtained. Ancillary studies, such as screening tests for GCA.

48. Vasculitis GCA can cause brief episodes of transient monocular or binocular visual loss. The episodes are characteristically precipitated by postural maneuvers due to anterior or posterior circulation compromise. As TVL may be a warning symptom for impending anterior ischemic optic neuropathy, an erythrocyte sedimentation rate, C-reactive protein, platelet count, and fibrinogen level should be obtained urgently in all older patients with TVL.

49. Systemic Hypoperfusion Systemic hypoperfusion due to hypotension or impaired cardiac output can produce brief episodes of transient binocular visual loss that are sudden in onset Characterized by a concentric loss of vision from the periphery. Other symptoms - lightheadedness , syncope, chest pain, palpitations, or dyspnea . Common causes - vasovagal attacks, cardiac arrhythmias, valvular heart disease ( eg , aortic stenosis ), and orthostatic hypotension.

50. Migraine Aura Common cause of episodic transient homonymous visual loss. The classic visual aura is the fortification spectrum, in which an achromatic or black and white figure with an angulated scintillating edge appears near the center of the visual field and gradually expands concentrically toward the periphery over minutes, leaving a bean-shaped scotoma .

51. Lasts for 15 minutes or longer, rarely for more than 60 minutes. Followed by a severe unilateral throbbing headache. In cases where the visual aura is always lateralized to the same side, the headache precedes the aura, or there is a persisting neurologic deficit, neuroimaging should be performed to exclude a structural lesion such as an arteriovenous malformation.

52. In basilar-type migraine, there may be an aura producing transient cortical blindness or homonymous visual field loss. An evaluation for alternative diagnoses, such as vertebrobasilar ischemia, is indicated, especially in older patients or those with vascular risk factors.

53. Occipital Seizures A sudden onset of binocular elementary positive visual phenomena with associated visual loss. The positive visual phenomena consist of multiple, brightly colored , small circular spots, circles, or balls. They are usually located in the contralateral hemifield . Vision is obscured in the area occupied by the hallucinations from the time of onset. The positive visual phenomena usually last for less than a minute.

54. Causes- PRES, metabolic encephalopathies , malformations of cortical development, neoplasms , vascular lesions, prior head trauma, metabolic diseases ( eg , mitochondrial disease), localized infections, or idiopathic.

55. PRES Transient cortical blindness and a variety of other homonymous visual field defects. Causes - malignant hypertension, preeclampsia, renal failure or in those taking immunosuppressive treatments. characterized by visual symptoms, headache, altered mental status, and seizures. Imaging typically shows bilateral subcortical and cortical edema in the occipital and occipito -parietal regions. With treatment directed toward the underlying cause, vision usually recovers over 1 to 2 weeks.

56. Angiography and Contrast Media Exposure Due to a breakdown of the blood-brain barrier by the contrast media with consequent neurotoxic effects. Symptoms - headache, altered mental status, and memory disturbances, typically develop during or shortly after contrast exposure. Extravasation of contrast in the occipital lobes on brain CT Brain MR imaging - increased signal in the occipital lobes without evidence of infarction.

57. Head Trauma Isolated transient cortical blindness may rarely result from minor blunt head trauma, usually direct occipital trauma, in children or adolescents. The visual loss commonly develops within minutes after the event. Imaging is typically normal. Most patients regain vision within minutes to hours. Neuroimaging should be obtained to exclude an intracranial hemorrhage .

58. Papilledema Well known cause of episodic TVL. Transient visual obscurations , are characterized by complete or partial loss of vision that lasts for seconds, followed by a rapid recovery of vision to baseline. Precipitated by postural changes and maneuvers that increase intracranial pressure. Occur many times per day. Due to transient ischemia of the swollen optic nerve head.

59. Neuroimaging should be obtained urgently to exclude a structural cause, such as a mass lesion, obstructive hydrocephalus, or venous sinus thrombosis. Patients with normal imaging should undergo lumbar puncture. Treatment of the underlying cause.

60. Optic Disc Drusen Brief episodes of TVL can occur in patients with optic disc drusen . Visible on funduscopy . However, when the drusen are buried, the disc appearance can mimic that of papilledema and B-scan ultrasonography or CT may be required to demonstrate their presence.

61. To conclude History Thorough examination including fundus and perimetry Newer techniques available Urgent diagnosis must in certain conditions to prevent permanent visual loss

62. Thank You

63. Referrences Diagnostic approach to visual loss. Newman et al. Continuum ( Minneap Minn ) 2014;20(4):785–815. Severe Visual Impairment and Blindness in Infants. Gogate et al. Middle East African Journal of Ophthalmology, Volume 18, Number 2, April - June 2011. Ocular and systemic causes of retinopathy in patients without diabetes mellitus. Venkatramani et al. BMJ 2004;328:625–9. Optical coherence tomography – current and future applications. M Adhi et al. Curr Opin Ophthalmol . 2013 May ; 24(3): 213–221. Bilateral visual loss Approach, localization, And Causes. Christopher C. Glisson . Continuum Lifelong Learning Neurol 2009;15(4). Disorders of the anterior visual pathways. S A Madill et al. J Neurol Neurosurg Psychiatry 2004;75( Suppl IV):iv12–iv19. Approach to acute visual loss. Khadilkar et al. Medicine update. 2012. Transient visual loss. Thurtell and Rucker. International ophthalmology clinics. 2009 .