Metamorphopsia As an Initial Complaint of Idiopathic Intracranial Hypertension

CLINICOPATHOLOGIC REPORTS, CASE REPORTS, AND SMALL CASE SERIES

SECTION EDITOR: W. RICHARD GREEN, MD

had Frisen stage 2 papilledema in the phopsia. Results of ocular coherence Metamorphopsia as right eye1 and stage 1 papilledema in tomography (OCT) of the macula an Initial Complaint the left eye (Figure 2A). There were were normal. A multifocal electroreti- of Idiopathic Intracranial no abnormalities of the maculae. A nogram (ERG) showed no focal Hypertension fluorescein angiogram showed no ab- abnormality corresponding to her normalities except for late staining of metamorphopsia. both optic nerves. Magnetic reso- Case 3. This 48-year-old woman We examined 4 patients in the past nance imaging (MRI) results were had had distortion of her vision bi- 6 years who were first seen at our normal, and lumbar puncture showed laterally for 6 to 12 months. Her institution because of metamor- an opening pressure of 280 mm CSF, medical history was notable for phopsia and who were eventually with normal indices. Treatment with asthma and hypercholesterolemia. diagnosed as having idiopathic in- acetazolamide resulted in improve- Review of systems was notable for tracranial hypertension (IIH). Idio- ment of the twinkling lights and non–pulse-synchronous tinnitus and pathic intracranial hypertension is gradual regression of the papill- rare headaches. Her ophthalmic his- a condition of elevated intracranial edema. The metamorphopsia im- tory was notable for myopia (–4.25 pressure that occurs primarily in proved slightly (Figure 1A). OU). She weighed 106 kg, was 157 young women. Neuroimaging find- Case 2. This 43-year-old woman cm tall, and had lost 7 kg in the past ings and cerebrospinal fluid (CSF) had had metamorphopsia in the right few months. indices are normal. Its cause is un- eye for 4 months. Her medical his- On examination, her visual acu- known, but recent weight gain is tory was unremarkable. Her oph- ity was 20/20 OD and 20/25 OS, with nearly universal. Symptoms in- thalmic history was notable for myo- distortion on the Amsler grid bilat- clude headache, pulse-synchro- pia and contact lens wear (–3.50 erally (Figure 1B). Examination find- nous tinnitus, visual obscurations, OU). She weighed 63 kg, was 152 cm ings were normal except for stage and diplopia. Most patients have tall, and had gained 7 to 9 kg dur- 2 papilledema in both eyes papilledema, and they may have ing the past year. (Figure 2C). A fluorescein angio- sixth nerve palsies. Optic nerve dys- Best-correctedvisualacuitywas20/ gram showed only late hyperfluo- function can occur if the papill- 20 OD and 20/15 OS. She described rescence of both optic nerves. The edema is severe or prolonged. distortion of the Amsler grid in the MRI results were normal. Lumbar right eye. Her examination findings Report of Cases. Case 1. This 46- were normal except for stage 2 pap- puncture showed an opening pres- year-old woman’s medical history illedema in the right eye (Figure 2B) sure of 310 mm CSF, with normal was notable for several sinus sur- and mild relative enlargement of the indices. A multifocal ERG showed geries. Her ophthalmic history was blind spot on automated perimetry in no abnormalities. Treatment with ac- notable for myopia (–5.00 OU). Fun- the right eye. There were tiny macu- etazolamide resulted in improve- dus photographs taken in 1993 lar drusen in the right eye. A fluores- ment of the papilledema, but no showed normal optic nerves, with a cein angiogram showed only late hy- change in the metamorphopsia. small choroidal hemorrhage in the perfluorescence of both optic nerves. Case 4. This 36-year-old woman right eye. At a routine follow-up visit The MRI results were normal except noticed spots missing in the vision in 1995 she complained of blurred, for a slightly tortuous optic nerve immediately after a hysterectomy distorted vision in the right eye dur- sheath in the right eye without en- 2 months earlier. Her medical his- ing the preceding 10 months. She hancementandanemptysella.Shede- tory was notable for asthma, depres- noted “twinkling lights” in her vi- veloped transient tunneling of vision sion, and an episode of carbon mon- sion on waking. She denied head- in the mornings, and on follow-up she oxide poisoning 16 years earlier aches, except for those associated had developed a new peripapillary without sequelae. Review of sys- with sinus problems. She weighed hemorrhage with stage 3 papilledema tems was notable for a few episodes 106 kg, was 168 cm tall, and had intherighteyeandstage1papilledema of pulse-synchronous tinnitus in the gained 14 kg during the preceding in the left eye. Lumbar puncture immediate postoperative period. She 4 years. showed an opening pressure of 275 also noted a pressure sensation Her visual acuity was 20/15 OU. mm CSF, with normal indices. Treat- around the eyes and in the occipi- She described distortion of the Am- ment with acetazolamide resulted in tal region. She had recently gained sler grid temporally in the right eye resolution of the tunneling and im- 12 kg, weighing 120 kg at a height (Figure 1A). Automated perimetry provement of the papilledema to stage of 165 cm. Her ophthalmic history showed enlargement of the physi- 1 in the right eye and stage 0 in the left was notable for mild myopia (–1.00 ologic blind spot in the right eye. She eye but no change in the metamor- OU). On examination, her visual

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Case 1, Right Eye, 11/1/1996 Case 1, Right Eye, 6/11/2002

Case 3, Left Eye, 8/28/2001 Case 3, Right Eye, 8/28/2001

Case 4, Left Eye, 4/06/2004 Case 4, Right Eye, 4/06/2004

Figure 1. A, Amsler grids drawn by case 1 at initial examination and at final follow-up showing paracentral distortion of the grid temporally in the right eye. B, Amsler grids drawn by case 3 at initial examination showing paracentral distortion of the grid temporally in both eyes. C, Amsler grids drawn by case 4 at initial examination showing paracentral distortion of the grid superotemporally in both eyes.

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Case 1, Right Eye Case 1, Left Eye

Case 2, Right Eye Case 2, Left Eye

Case 3, Right Eye Case 3, Left Eye

Case 4, Right Eye Case 4, Left Eye

Figure 2. Fundus photographs at initial examination. A, Case 1 showing stage 2 papilledema in the right eye and stage 1 papilledema in the left eye. B, Case 2 showing stage 2 papilledema in the right eye and stage 0 papilledema in the left eye. C, Case 3 showing stage 2 papilledema in both eyes. D, Case 4 showing stage 2 papilledema in both eyes.

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©2005 American Medical Association. All rights reserved. Downloaded From: https://jamanetwork.com/ on 09/26/2021 acuity was 20/20 OU with correc- lution necessary to detect subtle mis- Financial Disclosure: None. tion. She described distortion with- alignments of the photoreceptor Correspondence: Dr Warner, MD, out scotoma on the Amsler grid bi- layer. Patients with more severe meta- Department of Ophthalmology and laterally (Figure 1C). Examination morphopsia associated with more se- Visual Sciences, John A. Moran Eye findings were otherwise normal ex- vere papilledema do have distor- Center, University of Utah Health Sci- cept for stage 2 papilledema in both tions in their retinal anatomy ences Center, 50 N Medical Dr, Salt eyes (Figure 2D) and moderate en- discernible on OCT (J.E.A.W., un- Lake City, UT 84132 (judith.warner largement of the physiologic blind published data, 2004). @hsc.utah.edu). spots on automated perimetry in Despite the resolution of papill- Funding/Support: This work was both eyes. The MRI results were nor- edema, none of these patients had supported in part by an unre- mal. Lumbar puncture showed an complete relief of their metamor- stricted grant to the Department of opening pressure of 410 mm CSF, phopsia. We speculate that these pa- Ophthalmology and Visual Sci- with normal indices. Results of OCT tients did not experience complete ences from Research to Prevent of the macula were normal. No fol- relief of their metamorphopsia be- Blindness Inc, New York, NY. low-up data are available at this time. cause of the permanent anatomical 1. Frisen L. Swelling of the optic nerve head: a stag- disruption of photoreceptor align- ing scheme. J Neurol Neurosurg Psychiatry. 1982; Comment. Metamorphopsia is a vi- ment associated with prolonged pap- 45:13-18. sual distortion in which straight lines 2. Schutta HS, Corbett JJ. Intracranial hyperten- illedema. Three of the women had sion syndromes. In: Joynt JJ, Griggs RC, eds. appear curved, and it is commonly moderate myopia, and 1 had mild Clinical Neurology. Vol 2. Philadelphia, Pa: Lip- seen in disorders that disrupt the pincott Williams & Wilkins; 1998:1-57. myopia; it is possible that the normal orientation of the macular 3. Paton L, Holmes G. The pathology of anatomy of their myopic globes and papilloedema. Brain. 1911;33:389-432. photoreceptors. It may remit or it 4. Dailey RA, Mills RP, Stimac GK, Shults WT, Ka- may become permanent. Metamor- the topography of their retinas some- lina RE. The natural history and CT appear- phopsia has not specifically been how predisposed them to the devel- ance of acquired hyperopia with choroidal folds. opment of metamorphopsia. Two Ophthalmology. 1986;93:1336-1342. mentioned in reports of IIH, but by 5. Jacobson DM. Intracranial hypertension and implication it occurs in the many pa- patients had peripapillary hemor- the syndrome of acquired hyperopia with cho- rhages. We considered that the meta- roidal folds. J Neuroophthalmol. 1995;15:178- tients with IIH who have severe pap- 185. illedema, resulting in a macular star morphopsia could be a manifesta- or “fan”2 due to extravasation of fluid tion of subtle myopic degeneration from the edematous nerve between or of some other condition of the the nerve fibers into the macula. Se- peripapillary retina (such as acute Optical Coherence vere papilledema may also be asso- zonal occult outer retinopathy Tomographic Findings ciated with Paton lines (concentric [AZOOR]). However, none of these in X-linked Juvenile retinal folds surrounding the optic patients had refractive errors greater Retinoschisis nerve that may also induce meta- than –6.00, and none had ophthal- morphopsia).3 A syndrome of ac- moscopic or angiographic evi- X-linked juvenile retinoschisis is a quired choroidal folds and hyper- dence of myopic degeneration. In ad- progressive bilateral disease that is opia has been described with and dition, 2 patients (cases 2 and 3) had probably present at birth and has without IIH.4,5 The incidence of normal photoreceptor function been documented as early as 7 weeks metamorphopsia in patients with IIH when evaluated by multifocal ERG. of age.1 It was first reported by Haas may be underreported because of the It remains to be seen whether these in 18982 and has recently become other, more debilitating symptoms women harbor an occult form of better understood as a mutation of experienced by these patients, or be- macular degeneration that will be- the XLRS1 gene on the short arm of cause physicians fail to document its come apparent in the future. the X chromosome (Xp22).3 This presence. We describe 4 middle-aged mutation results in an abnormal reti- The cases we describe are all un- women with initial complaints of nal protein that participates in in- usual in that the metamorphopsia metamorphopsia coinciding with the tercellular spaces.3 Cystoid changes was associated with very mild pap- development of mild papilledema. arranged in a stellate pattern with ra- illedema (stage 2 or less). None of the Because no other cause of metamor- dial striae projecting from the fo- patients had visible distortions of the phopsia was discovered and be- vea are seen in all patients, along maculae, choroidal folds, macular cause of the temporal association be- with a peripheral schisis in 50% of edema, or hyperopic shifts. We tween the onset of metamorphopsia cases, and variable findings are well speculate that the metamorphopsia and the finding of papilledema, we described by Gass4 and others. In this was due to traction on the retina from believe that these patients experi- study, we used optical coherence to- nerve elevation, with resultant dis- enced metamorphopsia as an ini- mography (OCT) (Stratus OCT; Carl ruption of photoreceptor orienta- tial symptom of IIH. Physicians Zeiss Meditec AG, Jena, Germany) tion, or from fluid within the retina should consider the diagnosis of IIH to examine the foveal areas in 2 pa- or nerve fiber layer that was not ap- in patients with metamorphopsia tients with juvenile retinoschisis. parent by ophthalmoscopy, angiog- and optic nerve edema. Our OCT findings suggest that the raphy, or OCT. Although OCT is a foveal schisis is probably located in sensitive indicator of retinal abnor- Judith E. A. Warner, MD the outer plexiform layer, not in the malities, it probably lacks the reso- Bradley J. Katz, MD, PhD nerve fiber layer (NFL), as de-

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