Eye (1990) 4, 190--194

Visual Performance in Idiopathic Macular Holes

R. G. SMITH, S. J. HARDMAN LEA, N. R. GALLOWAY Nottingham

Summary Previously published reports on the clinical features of idiopathic macular holes highlight the predilection for post-menopausal women and implicate vitreomacular traction in the aetiology of these lesions. Relatively little attention, however, has been paid to the quality of visual loss in eyes with macular holes. Histological studies of full-thickness macular holes have shown loss of all retinal layers in the area of the hole, and this would be expected to produce a central absolute scotoma of the same diameter. The majority of patients with full-thickness holes in this series did not have an absolute scotoma large enough to be detected on the Amsler Chart or when read­ ing. It is suggested that following formation of a macular hole, enlargement may occur without further loss of foveal tissue and without enlargement of the absolute scotoma, due to tangential vitreous traction or contraction of an associated epiretinal membrane.

Since the first detailed description1 of a mac­ patierits with idiopathic macular holes as part ular hole by Noyes in 1871 much has been of a separate study, it was noticed that in no written about the pathogenesis, histopathol­ case was positive scotoma a presenting symp­ ogy, clinical features, and course of these tom, the most consistent complaint being that lesions. Although visual acuity is documented objects appeared distorted or fragmented. We as a matter of course in all such studies, rela­ present the results of the clinical assessment tively little attention has been paid to the of these patients, particularly with regard to quality of visual disturbance experienced by the type and severity of central vision patients with macular holes. disturbance. The cardinal symptoms of macular disease are positive scotoma, metamorphopsia, SUbjects and Method micropsia and macropsia. 2 From detailed his­ Twenty eight patients (24 female, four male) 60-81 69.9) tological descriptions of macular holes/,4 a with age range years (mean with full-thickness hole would be expected to give 32 idiopathic macular holes were recruited rise to an absolute scotoma, surrounded by an from outpatient clinics at the Queen's area of metamorphopsia (especially where Medical Centre. The lesions had been present there is an associated serous retinal detach­ for between three weeks and eleven years ment). With lamellar holes, disruption is con­ (Table 1) and presenting complaints included fined to the inner retinal layers4 and is less metamorphopsia (14 eyes), reduced vision likely to give rise to an absolute scotoma. (12 eyes) and difficulty reading (three eyes). While we were examining a group of Three holes were discovered incidentally by

From: Department of Ophthalmology, The Queen's Medical Centre, Nottingham.

Correspondence to: Mr R. G. Smith, FRCS FCOphth, Department of Ophthalmology, The Queen's Medical Centre, Nottingham NG7 2UH. VISUAL PERFORMANCE IN IDIOPATHIC MACULAR HOLES 191

Table I Duration of Macular Holes (32 eyes) ness holes and two had a full-thickness hole in one eye with a lamellar hole in the fellow eye. Duration Number Distance visual acuity in eyes with full­ thickness holes ranged from 0.03 (2/60) to 0-2 months 4 0.25 (6/24) with a mean of 0.13, and in eyes 3--6 months 2 7-12 months 7 with lamellar holes ranged from 0.33 (6/18) to 1-5 years 11 1.20 (6/5) with a mean of 0.5,? The difference >5 years 6 in visual acuity for the two types of macular Unknown 2 hole is significantat p

Length of time fromonset of symptoms to assessment performed on the logarithm of the. Snellen for this study. fractions). Near visual acuities (Standard reading test optometrists or ophthalmologists. All eyes types, Keeler, England) were converted to with macular holes were otherwise healthy Snellen equivalents by measuring the height and had no history of previous disease, sur­ of lower case letters without ascenders and gery or significant trauma. descenders and calculating the angle sub­ A full medical history was taken and clinical tended at the eye at a distance of 0.3 m. When examination included refraction, measure­ expressed as Snellen equivalents, visual acu­ ment of best corrected visual acuity at 6 m and ities at 0.3 m accorded closely with those at 0.3 m with a + 3.00 dioptre addition, central recorded at 6 m for all patients. visual field assessment (Amsler No. 1 Chart, Refractive errors of the macular hole eyes Hamblin, London), slit lamp biomicroscopy and fellow eyes showed a small tendency to­ and fundus photography. Amsler Chart exam­ ward hypermetropia but were not signifi­ inations were carried out according to the cantly different from a group of 119 control method recommended by Amsler5 with a eyes with 6/12 or better vision (Age range working distance of 0.3 m and the same spec­ 50-80, mean 63) taken from a local optomet­ tacle correction as used to test reading acuity. ric practice (Fig. 1). Fundus examinations were carried out using a An absolute scotoma was detected on the "Goldmann three mirror contact lens or a +90 Amsler Chart in eight eyes with full-thickness dioptre double aspheric lens. Macular hole holes. Because there was associated meta­ diameters were measured with the scale on morphopsia in all cases, the scotoma was the slit lamp (Haag Streit 900) and also with a sometimes difficultto delineate, but appeared graticule on the fundus photographs. In both to be less than 3° in diameter in all cases. Six­ cases, the measurement was made in compari­ teen eyes with full-thickness holes and five son with the vertical diameter of the optic eyes with lamellar holes detected only central disc, assuming this to be 1.75 ± 0.19 mm,6the distortion on the Amsler Chart. Two patients optic discs being morphologically normal in were unable to understand the test and one all cases. patient with a lamellar hole perceived no The distinction between full-thickness and distortion. lamellar holes was made on the biomicro­ Complete posterior vitreous detachment scopic criteria of Gass.4 No difficulties were (PVD) appeared to be present in 15 eyes encountered in making this distinction and (58%) with full-thickness holes and five eyes routine fluorescein angiography was not felt (85%) with lamellar holes. Partial PVD was to be necessary. present in two eyes (8%) with full-thickness All clinical assessments were carried out by holes. One eye with a lamellar hole showed two of the authors (R.S. and S.H.-L.). partial PVD with vitreous traction to an ele­ vated flap of foveal tissue. Surprisingly the Results patient was unaware of any metamorphopsia. Of the 32 macular holes, 26 were classified as Nine eyes, all with full-thickness holes had no full thickness and six lamellar. Of the four evidence of PVD on biomicroscopy. patients with bilateral holes, one had bilateral Diameters of full-thickness holes ranged lamellar holes, one had bilateral full-thick- from 0.35-0.9mm (mean 0.57, SD 0.13 mm) 192 R. G. SMITH ET AL.

D Controls Frequency II Patients

-7 - 6 - 5 -4 -3 -2 -1 0 234 5

Refractive Error

Fig.1. Mean spherical equivalent refractive errors for eyes with macular holes andfellow eyes (52 eyes) compared with 119 eyes with 6/12 or better vision taken from records from a local optometric practice. The differencebetween the two groups is not statistically significant. and diameters of lamellar holes ranged from the clinical features of macular holes. 4.7-10 The 0.35--D.7 mm (mean 0.48, SD 0.15 mm). The condition has consistently shown a predilec­ difference between the groups was not tion for post-menopausal women (86% of significant. patients in this series and 70-77% in the series There was no correlation between macular cited above). Although vitreomacular trac­ hole diameter and visual acuity, nor between tion is strongly implicated in the aetiology of macular hole diameter and the presence or macular holes, the association with posterior absence of an absolute scotoma. However, vitreous detachment (PVD) is less clear. The macular hole diameter showed a significant incidence of PVD in previously reported correlation with the time since the onset of series varies from 40% to 100% ,7-10 but not all symptoms (pHypertension 9 being hypertension (Table II). As far as is Ischaemic Heart Disease 5 known, none of the female patients had Hypercholesterolaemia 2 Cerebrovascular Disease 1 undergone hysterectomy or had taken hor­ Diabetes Mellitus 2 mone replacement therapy. Of the28 patients with macular holes, a number were Discussion receiving treatment for the medical conditions shown A number of recent reports have highlighted above. VISUAL PERFORMANCE IN IDIOPATHIC MACULAR HOLES 193 the margin of the hole, similar to one case in The loss of foveal tissue in the development our series. They concluded that vitreomacular of a full-thickness hole presumably occurs by adhesion, combined with intravitreal traction avulsion of an operculum during detachment or the process of posterior vitreous separation of the posterior vitreous face, or secondary to was responsible for macular hole formation. degenerative changes in the fovea.13 If, as Gassll has suggested that tangential traction Gass suggests, tangential traction from the from the posterior vitreous surface may also posterior vitreous may contribute to the be an aetiological factor. It may be that tan­ development of macular holes, this might pro­ gential traction forces are important in those vide a basis for enlargement of the hole with­ cases where there is no evidence of PVD out further loss of retinal tissue. Smiddy et (28% of eyes in this series). al.13 have found during vitrectomy for Morgan and Schatz9 reported a close corre­ 'impending macular hole' that a thin layer of lation between macular hole diameter and cortical vitreous may remain adherent to the visual acuity at the initial assessment (61% macula despite apparently complete posterior were assessed within a year of onset of symp­ vitreous detachment on biomicroscopy. Gass4 toms), but noted that the diameter of holes has also shown that lamellar holes may be tended to increase during a period of fol­ associated with a cellular epiretinal mem­ low-up, though visual acuity remained stable. brane which contracts, throwing the retinal The lack of correlation between macular hole surface adjacent to the hole into small folds. diameter and visual acuity in this series is If a macular hole enlarges through 'centrif­ likely to be due to the fact that 53% of holes ugal' traction on it's margins, whether due to had been present for more than 12 months vitreous attachments or an epiretinal mem­ and 19% for more than five years. This is also brane, but without any further loss of foveal reflected in the strong correlation between tissue, the enlargement would occur without duration of symptoms and hole diameter. an increase in the size of an associated abso­ It has been noted previously that central lute scotoma. The low incidence of a detect­ scotoma is rarely a presenting symptom of able scotoma in the eyes with full thickness macular holes.9 Mitra12 detected absolute sco­ holes in this series could be explained on this tomas of up to 2.5" by means of contrast sensi­ basis. tivity gratings in all of a group of ten patients In conclusion, the clinical findings in this with full-thickness macular holes. However, series of eyes with idiopathic macular holes 50% of these measured P or less. No details are in broad agreement with those of pre­ of the diameter of the holes were given. It is viously published series, but we draw atten­ likely that a number of our patients with full­ tion to the unexpectedly low incidence of thickness holes failed to recognise an absolute central absolute scotomas in eyes with full­ scotoma on the Amsler Chart because their thickness holes and suggest that this may be scotoma was lOin diameter or less (ie less than due to enlargement of the hole without tissue one square on the chart). Accurate plotting of loss by tangential traction on it's margins. small central scotomas is a problem whichever References method is used because of the difficulty of 1 Noyes HD: Detachment of the retina, with lacer­ Tr Am Ophthalmol Soc maintaining fixation. Our patients could ation at the macula lutea. 1871,1: 128. usually say with confidence whether any lines 2 Kanski JJ: Clinical Ophthalmology. Butterworths, on the Amsler Chart were missing or not, but 1984, 12: 3. found it difficult to count how many lines or 3 Kornzweig AL and Feldstein M: Studies of the eye Am J Ophthalmol1950, 33: 243-7. squares were missing. For this reason, it was in old age. 4 Gass JDM: Lamellar macular hole, a complication only possible to measure the size of an abso­ of cystoid macular edema after cataract extrac­ lute scotoma approximately. tion. Arch Ophthalmol1976, 94: 793-800. If the size of the absolute scotoma corre­ 5 Amsler M: Earliest symptoms of disease of the mac­ sponded exactly with the diameter of the mac­ ula. Br J Ophthalmol1953, 37: 521-37. 6 Straatsma BR, Foos RY, Spencer LM: The retina: ular hole, a hole of 0.5 mm diameter would 1.80 topography and clinical correlations. Symposium result in an absolute scotoma of and a on retina and retinal surgery. Trans New Orleans 0.75 mm hole would give a 2.80 scotoma. Acad Ophthalmol Mosby, St.Louis. 1969,1-26. 194 R. G. SMITH ET AL.

7 Aaberg TM, Blair CJ, Gass JDM: Macular holes. H Gass JDM: Macular dysfunction caused by vitreous Am J Ophthalmol1970, 69: 555-62. and vitreoretinal interface abnormality. Vitreous 8 McDonnell PJ, Fine SL, Hillis AI: Clinical features traction maculopathies. Stereoscopic Atlas of of idiopathic macular cysts and holes. Am J Oph­ Macular Disease. St Louis, CV Mosby Co. 1987, thalmoll982, 93: 777-86. 676-93. 12 9 Morgan CM and Schatz H: Idiopathic Macular Mitra S: Spatial contrast sensitivity in macular dis­ Holes. Am J Ophthalmol1985, 99: 437-44. order. Doc Ophthalmol1985, 59: 247-67. 10 1 Trempe CL, Weiter JJ, Furukawa H: Fellow eyes in 3 Smiddy WE, Michels RG, Glaser BM, de Bustros S: cases of macular hole. Biomicroscopic study of Vitrectomy for impending idiopathic macular the vitreous. Arch Ophthalmol1986, 104: 93-5. holes. Am J Ophthalmol1988, 105: 371-6.