Brit. J7. Ophthal. (1976) 6o, 124 Br J Ophthalmol: first published as 10.1136/bjo.60.2.124 on 1 February 1976. Downloaded from

Intraocular surgery in advanced

E. J. O'CONNELL AND A. G. KARSERAS From the Department of , University Hospital of Wales, Heath Park, Cardiff

It has been found that 40 per cent of glaucomatous surgery may result in obliteration of the central patients registered blind or partially sighted, are subserving macular function when this registrable when they first present for ophthalmic is threatened by preoperative glaucomatous field supervision. In addition, opacity contributes loss. Lichter and Ravin (i974) have summarized significantly to visual disability in registered the historical development of this view. glaucomatous patients (Miller and Karseras, 1974). The present study attempts to define the inci- Drainage procedures, and/or lens extraction, may dence of postoperative loss of central vision, therefore have to be considered in eyes in which consequent upon modem drainage procedures and/ visual reserves are grossly reduced from glaucoma- or extractions. tous field loss. There is an established view that intraocular Material and method A review of the case histories of glaucomatous patients Address for reprints: A. G. Karseras, FRCS, University Depart- ment of Surgery, Welsh National School of Medicine, Heath Park, who have had drainage procedures or cataract extraction Cardiff CF4 4XN was undertaken. Those patients whose preoperative copyright.

Table I Quadrantic nasal field loss ± arcuate Preoperative status Postoperative status (after 6 months) Intraocular Corrected Intraocular Patient Visual pressure Visual field Lens Operation visual pressure Macular Lens acuity (mmHg) opacity acuity (mmHg) function opaci. http://bjo.bmj.com/ I 6/9 30 Upper nasal quadrantanopia Iridencleisis 6/9 22 No change - Lower arcuate defect 2 6/9 32 Lower nasal quadrantanopia Scheie Counting 35 No change fingers (see corrected comment) to 6/9 (see comment) 3 6/i8 34 Upper nasal quadrantanopia Trabeculectomy 6/I8 I0 No change + Lower arcuate defect 4 6/6 28 Upper nasal quadrantanopia Scheie 6/6 IS No change 5 6/6 so Lower nasal quadrantanopia Trabeculectomy 6/6 I5 No change on September 26, 2021 by guest. Protected 6 6/6 28 Upper nasal quadrantanopia Trabeculectomy 6/6 i8 No change 7 6/6 30 Upper nasal quadrantanopia Trabeculectomy 6/6 21 No change 8 6/68 30 Lower nasal quadrantanopia Trabeculectomy 6/x8 29 No change 9 6/9 40 Lower nasal quadrantanopia + Trabeculectomy 6/9 13 No change I0 6/9 28 Upper and lower quadran- Trabeculectomy 6/9 14 No change + tanopia (nasal hemianopia) I I 6/9 6o Upper nasal quadrantanopia Scheie 6/9 8 No change 12 6/9 30 Upper and lower quadran- Trabeculectomy 6/9 14 No change tanopia (nasal hemianopia) 13 6/6 38 Upper nasal quadrantanopia Trabeculectomy 6/6 14 No change 14 6/24 40 Upper hemianopic defect Trabeculectomy 6/36 I4 No change (nasal and temporal) IS 6/9 48 Upper and lower quadran- Iridencleisis 6/9 14 No change tanopia (nasal hemianopia) I6 6/6 22 Upper nasal quadrantanopia Iridencleisis 6/6 IS No change '7 6/9 28 Upper nasal quadrantanopia Trabeculectomy 6/9 '4 No change I8 6/I2 32 Upper nasal quadrantanopia Trabeculectomy 6/12 20 No change '9 6/i8 32 Upper nasal quadrantanopia + + Trabeculectomy 6/i8 9 No change 4- + 20 6/6o 40 Upper and lower quadran- Trabeculectomy < 6/6o x6 No apparent ++ tanopia (nasal hemianopia) change 21 6/6 22 Upper nasal quadrantanopia - Trabeculectomy 6/6 IS No change with lower arcuate 22 6/36 30 Upper nasal quadrantanopia + + Trabeculectomy 6/36 20 No change + + Intraocular surgery in advanced glaucoma 125 Br J Ophthalmol: first published as 10.1136/bjo.60.2.124 on 1 February 1976. Downloaded from

field loss encroached on central fixation were selected fixation directly attributable to the operation was for this study. They were divided into two groups: therefore recorded but possible medium or long-term I. 24 eyes with a residual central island, with or postoperative was not excluded in some without a temporal island of vision instances (Table III). The visual acuity of each patient 2. 22 eyes in which an arcuate scotoma not only at the final review was recorded. approached to within 50 of central fixation but Preoperative field analysis in the cataract extraction had extended to the peripheral field to cause a group (Table III), Patients I to 8, was carried out nasal quadrantic defect. several months, and in some instances years, before An additional arcuate scotoma was occasionally extraction, when the visual acuity and amount of lens present. Five patients from Group I and three from opacity allowed accurate Goldmann perimetry. Patients Group 2 subsequently had cataract extractions. Five 9-I3, because of gross cataract and glaucoma at presen- eyes in three patients who presented with coincidental tation, did not have perimetry. Visual fields were cataract and late glaucoma also underwent cataract assessed by confrontation to hand movement and extraction. An analysis of the results of these 13 cataract perception of light. extractions was undertaken. The difficulty in assessing macular function in the Preoperative and postoperative data recorded in both presence of cataract and a glaucomatous nasal quad- groups included visual acuity, intraocular pressure, rantic or hemianopic field defect is discussed later. Goldmann perimetry, an assessment of lens opacity, and the drainage procedure undertaken. Postoperative data from both groups were recorded Results of surgery. Loss of fixation 6 months from the day Table I shows that drainage operations on eyes after such an interval was not considered attributable to the drainage procedure. The present status of each with quadrantic field loss did not lead to any patient was ascertained and any change of status after further loss of visual field involving macular 6 months was recorded. fixation. The postoperative status of the cataract group (Table In Patient 2 the visual acuity fell from 6/9 to

III) was assessed 2 months after extraction when the counting fingers immediately postoperatively. This copyright. eyes were free from postoperative inflammation. Loss of was found to be due to lenticular which, when corrected, restored the visual acuity to its preoperative level. Nuclear sclerosis developed after 6 months, but cataract extraction at i yr, although al review complicated by vitreous loss, restored the visual acuity to 6/9 (Table III, Patient 7). te Visual acuity Comments (operated eye*) The only instance in which the preoperative

visual acuity of 6/I8-6/24 could not be explained http://bjo.bmj.com/ 12 Counting fingers 6/9* Left cataract extraction at is/I2 by any condition other than glaucomatous field 6/I2* 6/6 Postoperative loss wrongly attributed loss was that of Patient i4. The sequence of field to loaa of visual field in patient was also unusual, in that tem- Right cataract extraction at I yr loss this (vitreous loss) poral field loss, giving an altitudinal hemianopia, succeeded a nasal quadrantanopia instead of the 6/X8* 6/X8 Bilateral lens opacities more usual development of a nasal hemianopia. 6/6* 6/6 Patient died at 6/12 on Table II illustrates that drainage operations on September 26, 2021 by guest. Protected 6/6* 6/6 not cause an 12 6/6* 6/6 eyes with central islands of vision did I2 6/6 6/6* obliteration of macular function from extension of 12 6/9 6/24* Slight increase in cataract affecting 6/S 6/24* Development of cataract visual field loss. There is a higher morbidity 6/36 6/9* Left corrected lenticular myopia visual acuity than in the quadrantic field loss group, and losses in visual acuity therefore occurred in 12 6/9* 6/9 )/12 6/12 6/9* nine out of 24 eyes immediately postoperatively. In Patients 5, 12, and 22 the cause was first attri- )/i2 6/6 6/6* 12 6/36* 6/4 Atypical field loss and visual acuity buted to loss of central field, but later to the preoperatively presence of a correctable lenticular myopia. When 12 6/9* 6/9 cataract became apparent, subsequent extraction Hand movements 6/i8* Lens opacity developing restored the visual acuity to the pre-drainage level 12 6/9* Counting fingers (Table III: Patients 4, 2, and 5). 6/12* 6/6 Branch vein occlusion (right) 12 6/12 6/36* Increasing cataract Patient I5 was considered to belong to this [2 Hand movements* Macular function could not be group but refused operation. It was first thought No perception of light assessed as patient refused lens extraction that Patient i7 had lost central fixation, but the 6/6 6/6* study revealed a divergent squint with a facultative suppression of the preoperative vision. Three 6/12 6/60* Preoperative lens opacity increasing weeks' postoperative occlusion (for shallow an- xa6 British Journal of Ophthalmology Br J Ophthalmol: first published as 10.1136/bjo.60.2.124 on 1 February 1976. Downloaded from

Table II Residual central island ± temporal island

Preoperative statuts Postoperative status (after 6 months) Intraocular Intraocular Patient Visual pressute Visual field Lens Operation Visual pressure Macular Lens acuitv (mmHg) opacity acuity (mmHg) function opacit

6/i8 44 Central island + Trabeculectomy 6/I8 I8 No change + 2 6/36 32 Central island + + Trabeculectomy 6 36 9 No change ++

3 6/6 .42 Central island and - Scheie 6/6 50 No change temporal island 4 6/12 44 Central island - Scheie 6/I8 I8 No change 5 6/9 29 Central island - Scheie Counting 25 No change + + fingers (see comment) 6 6/6 6o Central island and - i. Stallard Counting 20 Lost central island temporal island 2. Scheie fingers

6/i8 42 Central island and + Iridencleisis 6, i8 9 No change + temporal island 6/12 48 Central island Iridencleisis <6/6o 8 Gross reduction in macular function 6/12 30 Central island + Scheie 6/6o i8 Gross reduction in macular function I0 6/6 70 Central island Iridencleisis 6/6 13 No change I I 6/24 24 Central island T Trabeculectomy 6/24 I7 No change 12 6/6 31 Central island Scheie 6/24 I7 No change comment) (see copyright. 13 6/I8 28 Central island Trabeculectomy 6!24 i8 No change ++ 14 6/9 44 Central island ± Iridencleisis 6/9 I8 No change 15 6/9 42 Central island and Stallard 6/I8 I8 No change temporal island ±± I6 6/9 50 Central island and --OOOOS Scheie Hand I8 Reduction of macular temporal island movements function 17 6/9 44 Central island --OOOOS Scheie 6,'9 20 No change i8 6/24 62 Central island and Trabeculectomy 6/24 I5 No change temporal island

I9 6/i8 24 Central island + Trabeculectomv 6/i8 '4 No change - http://bjo.bmj.com/ 20 6/9 28 Central island Trabeculectomy 6/9 14 No change 21 6/6 46 Central island Trabeculectomy 6/6 i8 No change 22 6/9 34 Central island Scheie 6/6o 21 See comment 23 6/6 44 Central island and Trabeculectomy 6/6 26 No change temporal island 24 6/9 40 Central island and Iridencleisis 6/12 23 No change temporal island on September 26, 2021 by guest. Protected terior chamber), a lack of binocular field available lead to worsening of central vision. Three patients for fusion, and a possible pre-existent out of the i3 did not obtain an improved visual may have contributed to this status. acuity. In Patients i and 9 this was due to maculo- In three instances there was an irreversible loss pathy and in Patient I 2 to absence of macular of visual acuity - due to a postoperative maculopathy function. Maculopathy also restricted visual im- (Patient x 6), exacerbation of a preoperative maculo- provement to 6/i8 in Patient 8. pathy (Patient 8), and a maculopathy which de- Of the five eyes (i to 5) with an isolated central veloped coincidentally with a cataract postopera- visual field, four (2 to 5) survived a drainage pro- tively, or subsequent to an eventual cataract extrac- cedure and a cataract extraction allowing visual tion (Patient 9, Table II; Patient i, Table III). acuities of 6/9. In Patient i a coincidental maculo- After two unsuccessful drainage procedures pathy restricted vision to the preoperative level of with very raised intraocular pressures Patient 6 perception of light. lost central fixation, and it is not certain whether the The three (Patients 6-8) with charted pre- surgery or the uncontrolled pressure was the cause. extraction quadrantic defects did not lose central Patient 7 lost central vision 2 years after the fixation after a cataract extraction or a preceding drainage procedure. drainage operation. Table III shows that cataract extraction did not The five eyes (9 to 13) belonged to three patients Intraocular surgery in advanced glaucoma 127 Br J Ophthalmol: first published as 10.1136/bjo.60.2.124 on 1 February 1976. Downloaded from

DRAINAGE OPERATIONS AND CATARACT FORMATION IN ADVANCED GLAUCOMA review Within 6 months, in the 'central island' group of 24 patients, postoperative lens opacities signifi- Visual acuity Comments cantly reduced vision in five patients (Table II, (operated eye*) Patients 5, 9, 12, 15, and 22). After the period of 6/9 6/I8* final review had progressed in a further 2 6/12* 6/36 (lens opacity Cataract extraction at I yr five patients (Patients 2, II, 13, i8, and 24). Pre- and quadrantic loss Prefers to function with aphakic of visual field) central island operative lens opacities were present in four of 6/6* 6/5 Stallard procedure 3/12 before those io patients (Patients 2, II, I3, and i8). In Scheie cataracts at Preoperative maculopathy the four Scheie operations the developed :2 within 6 months and were not associated with 6/I8* 6/9 Cataract extraction at I yr Bilateral , loss of fixation preoperative lens opacities. In the four trabeculec- originally diagnosed tomies there were preoperative lens opacities and 2 Hand movements* 6/9 5 wk between the 2 operations with these progressed significantly after the 6-month intraocular pressure 50 mmHg Flat anterior chamber and choroidal interval. detachment after Scheie Within 6 months, in the 'quadrantic loss' group 2 Hand movements* 6/5 Central vision loss at 2 yr Gradual deterioration of 22 patients, postoperative lens opacities signifi- 2 Counting fingers Progressive maculopathy in both eyes cantly reduced vision in one patient (Table I, counting fingers* Pathological myopia Patient 2) and this was corrected to 6/9. After the Perception of light* Cataract extraction at 2i yr showed 6/36 gross maculopathy period of final review cataracts had progressed in a 6/6* 6/9 further eight eyes (Patients I, 8, 9, Io, I6, I9, 20, 6 i8 6/60* Increase in cataract 2 6/9* counting fingers Cataract extraction at I yr and 22). Preoperative lens opacities were present

Patient functioning with aphakic central in five of these eyes. copyright. island of 2 6/60* 6/36 Bilateral lens opacities Consideration both groups (Tables I and II) 6/6 6/9* shows that 10 out of 25 trabeculectomies resulted z 6/36* hand movements Increasing lens opacities in the progression of lens opacities, but that pre- 6/36 hand movements* Postoperative exudative maculopathy operative opacities were present in nine of these. Five out of I2 Scheie operations were associated 6/9* 6/9 Divergent squint with suppression Difficulty in locating test type with progressive postoperative cataract and pre- 2 6, 9 counting fingers* Progressive lens opacities operative lens opacity was present in one instance.

6/i8* 6/6o Inequality of follow-up does not allow valid com- http://bjo.bmj.com/ 6/ 12 6/9* parison between the Scheie and trabeculectomy 6/,12* 6/9 procedures, but at the 6-month level, trabeculec- 619* 6/I2 (aphakic) Cataract extraction at 2/12 yr 6/6* 6/9 tomy would appear to induce less deterioration of visual acuity of lenticular origin. Counting fingers* Progressive cataract both eyes 6/6 (aphakic) Cataract extraction at 3 yr Discussion Lichter and Ravin (I974) correctly stated that on September 26, 2021 by guest. Protected who presented with both advanced glaucoma and many of the opinions regarding loss of central cataracts. Intraocular pressures were controlled vision in late glaucoma after intraocular surgery medically before extraction in three eyes (Patients are the result of clinical impression rather than 9, io, and ii) and by peripheral iridectomy and of the study of a series of patients. It is of interest medical treatment in two (Patients I2, I 3). to analyse the relatively few series which have led Considerable improvement in visual acuity to a reluctance to undertake intraocular surgery in resulted in eyes io, ii, and 13. The postoperative advanced glaucoma. development of maculopathy in Patient 9 allowed Bloomfield and Kellerman (I949) compared the only the preoperative vision of 6/6o. results of surgery in i 9 patients with those of Patient I2 was the only example in the present medical treatment in 22 patients. All had residual series in which macular function was lost before central islands and after an average follow-up the development of a nasal hemianopia. This period of 2 years and 4 months it was found that patient had chronic angle-closure glaucoma with vision was better maintained in the unoperated intraocular pressures of 6o mmHg at presentation. group. The cause of reduction in visual acuity was Central fixation was absent postoperatively. In not determined so that reversibility of the condition Patients 8 to I 2 macular function could not be was not excluded. demonstrated preoperatively. The present study showed that postoperative 128 British Journal of Ophthalmology Br J Ophthalmol: first published as 10.1136/bjo.60.2.124 on 1 February 1976. Downloaded from

Table m Cataract extraction group

Preoperative status Postoperative status (2 months) Intraocular Intraocular Patient Corrected visual pressure Visual field Corrected visual pressure Macularfunction acuity (mmHg) acuity (mmHg)

I Perception of light 8 Central island with temporal island Perception of light I8 See comment

2 6/36 17 Central island 6/9 l6 Maintained

3 Hand movements 5 Central island 6/9 I6 Maintained

4 Counting fingers 25 Central island 6/9 I8 Maintained

Counting fingers 2I Central island 6/9 I5 Maintained

6/36 22 Upper nasal quadrantanopic loss 6/6 24 Maintained with lower arcuate defect Counting fingers 30 Lower nasal quadrantanopic defect 6/9 8 Maintained copyright. 6/6o Ir8 Upper nasal quadrantanopic defect 6/I8 21 Partially maintaine 6/6o 17 Lower nasal quadrantic defect 6/6o I6 See comment

I0 Hand movements 20 Upper and lower quadrantic defects 6/I2 20 Maintained (nasal hemianopia) II Counting fingers 24 Nasal hemianopia 6/I2 20 Maintained http://bjo.bmj.com/

I2 Counting fingers 2I Upper nasal quadrantic defect Counting fingers 20 Absent (? lost fron extraction)

13 6/6o 32 Upper nasal quadrantic defect 6/9 IS Maintained on September 26, 2021 by guest. Protected

and cataract formation accounted the results of surgery. Thus only 6 per cent of for the loss of visual acuity postoperatively in 212 eyes with a preoperative vision of more than four out of so patients (Table II). Only five out of 6/6o 'turned blind' after operation and 64 eyes the total of the 24 central island group had signifi- with a preoperative vision of 6/6o or less had an cant irreversible reduction of vision, up to the time incidence of 64 per cent blindness. All patients of the final review (Table II, Patients 6 to 9, i6). had a 'contraction of the visual field as low as 50 The trephine operations and the acknowledged in one quadrant'. inexperience of some surgeons would have in- Glaucomatous field loss does not significantly creased the reversible postoperative loss of acuity reduce the visual acuity unless it extends to inside in Bloomfield and Kellerman's series. The amount the 50 isoptre (see below). In the series of Nemetz of irreversible macular loss in uncontrolled medi- and Papapanos it is likely that macular fixation cally-treated patients would also increase with a was involved preoperatively in most of the 64 follow-up longer than the 2 years averaged. eyes or that there was a non-glaucomatous cause Nemetz and Papapanos (1959) found that visual for the preoperative vision of 6/6o or less. These acuity was the most significant factor influencing eyes therefore cannot be said to have lost central Intraocular surgery in advanced glaucoma I29 Br J Ophthalmol: first published as 10.1136/bjo.60.2.124 on 1 February 1976. Downloaded from

was justified only if the limits of the visual field did not encroach more than 50 from fixation and that loss of fixation was probable if the encroach- I review ment was 30 or less. This supposition is not borne out by the recent Visual acuity Comments (operated eye*) results of Lichter and Ravin (I974) or those of the present series. We found that the patients' response 6/6 Perception of light* Large white scar at macula observed incon- (aphakic) postextraction to perimetry inside the 50 isoptre is usually Drainage procedure 2s yr before stant and that the actual visual acuity is the best extraction method of determining macular involvement in 2 6/9 counting fingers Drainage procedure I yr before extraction glaucomatous field loss in these circumstances. We Functioning well with aphakic central found that acuity fluctuated at different examina- island 6/12* 6/36 (phakic) Drainage procedure xi yr before tions, usually between 6/9 and 6/i8 and, exception- extraction ally, 6/24 (Patient i4, Table II). Patient prefers to function with aphakic central island Careful refraction and time for the patients' 6/I8* 6/9 Drainage procedure I yr before concentration and orientation of visual direction extraction Bilateral aphakia were the most important factors in eliciting the 6/9* 6/I2 (phakic) Drainage procedure i 2/I2 yr before maximum visual acuity. When fixation is involved extraction Difficulty in locating test chart but the acuity is invariably less than 6/6o and when eye is unused, being held in reserve the condition is due to glaucomatous field loss 6/9* counting fingers Drainage procedure I 3/I2 yr before extraction the decline to this level is dramatic unless other Functioning well with aphakic eye factors such as cataract have already lowered 6/12* 6/6 (phakic) Drainage procedure i yr before the to between 6/24 and 6/6o. extraction acuity

Operated eye held in reserve Lichter and Ravin (1974) attempted to classify copyright. Vitreous loss late glaucoma in terms of visual acuity and field 6/I8* counting fingers Maculopathy evident postoperatively Patient died at 9/I2 loss. They did not give a full description of the 2 6/i8 6/60* Progressive maculopathy reduced visual fields but in 23 eyes in which visual field visual acuity of 6/24 to 6/6o 2 6/12* 6/24 Cyclodialysis 3/I2 postoperatively loss 'involved fixation' (as shown by a reduced Bilateral aphakia. visual acuity), and in nine eyes in which field loss 2 6/12 6/24* Slight membrane over Visual acuity transiently 6/I2 extended to within 5° of fixation, drainage pro- Macula function not thought to be cedures did not influence macular function. Loss present preoperatively but patient

of acuity was attributed to cataract and this caused http://bjo.bmj.com/ insisted on extraction in view of result of first operation (Patient io) a similar loss of acuity postoperatively in glauco- Normal visual functioning matous eyes in which fixation was not threatened. 6/I2-6/I8 counting Iridectomy before extraction (sub- fingers* acute angle closure) The present investigation has also revealed that Macular function could not be postoperative cataracts reduce the visual acuity. demonstrated in early stages of cataract They occurred earlier, and with a greater effect on 2 6/12-6/18* counting Iridectomy I yr before extraction vision, in the central island group than in the nasal fingers (subacute angle closure) field defect group. This may mean that the more Visual functioning much improved on September 26, 2021 by guest. Protected severe the glaucomatous damage, the more vul- nerable are the eyes to postdrainage cataract forma- tion. Alternatively, the 'tunnel' vision of these fixation as it is unlikely to have been present eyes may be more vulnerable to minor lens opaci- preoperatively. ties. The number of trabeculectomies carried out Fanta and Herold (i966) undertook static peri- was also much lower in the central island group, metry before and after operation on io eyes in and this operation appears to be much less likely which the macular fixation was approximated by to cause postoperative lens opacity, at the 6-months glaucomatous field loss. They demonstrated a fall level of follow-up. in the profile of sensitivity to static perimetry and Lichter and Ravin's series was remarkable be- a reduction of the functioning field in all instances. cause of the absence of any postoperative maculo- However, fixation was maintained in eight of their pathy. In the central island group (Table II) in cases. Of the two who lost fixation, one was a high the present series maculopathy reduced vision myope (Case io). In the other (Case 8), the inferior postoperatively in three out of 24 eyes (I2-5 scotoma, almost splitting fixation preoperatively, per cent). Postoperatively maculopathy was not was questionably glaucomatous as it was atypical seen in the nasal field defect group. It appears in shape and crossed the horizontal meridian from this series that the central island group is nasally. Fanta and Herold suggested that operation more vulnerable not only to postoperative cataract 130 Brtish Journal of Ophthalmology Br J Ophthalmol: first published as 10.1136/bjo.60.2.124 on 1 February 1976. Downloaded from

formation, but also to postoperative maculopathy. and three quadrantic loss). Maculopathy restricted Of a total of 46 drainage procedures (Tables I and visual improvement in two eyes with quadrantic II), however, maculopathy developed in three field loss. eyes (7 per cent). These findings suggest that cataract extraction Lawrence (I969) found a similar postoperative in eyes with advanced glaucoma will usually incur morbidity regarding cataract and maculopathy. benefit to the patient and that the risk of removing In I9 eyes with residual central islands, central the small amount of sight the patient may have, is fixation was not lost but visual acuity was reduced small (reduction or loss of visual acuity was not as a result of cataract in six eyes and maculopathy recorded in the present series or in Lawrence's in one. In 24 eyes with 'quadrantic' field loss, eight cases). Failure to improve the vision may occur central fixation was maintained but vision was in 24 per cent of patients (five out of 2I extractions, reduced by cataract in seven eyes and by macular combining data of Lawrence and present series), degeneration in eight. All were eyes which had mainly due to an increased incidence of maculo- been trephined and this operation would appear to pathy. Sixteen of these eyes were subjected to cause a greater postoperative morbidity. drainage operations before cataract extraction. Both Kronfeld and McGarry (1948) found that, in i8 series show the development of a postdrainage eyes with field defects extending to within 50 of maculopathy in some of these patients with late fixation (mainly central islands), 95 per cent re- glaucoma, so that the culpability of the cataract tained fixation for 5 years postoperatively. Imme- extraction itself may be less. diate postoperative loss of fixation was not recorded. In the monitoring of glaucoma simplex a gradual Twelve eyes with similar field defects, uncontrolled progressive loss of visual acuity is frequently medically, were not operated upon and nine (75 observed. This gradual loss is not due to glauco- per cent) retained fixation during 5 years. Although matous field loss (despite apparent changes in their study supports the view that surgery does perimetric field analysis), but often to progressive

not significantly affect fixation, it does call into lens opacity. We have found that, as in retinitiscopyright. question the wisdom of surgery in elderly patients pigmentosa with residual macular function, minor with advanced glaucoma in whom pressures are not lens opacities severely affect visual acuity in late greatly raised or have been reduced significantly glaucoma. When loss of visual acuity is severe by medical therapy. enough lens extraction will improve the sight in The present series has shown that the risk of over 75 per cent of patients. Six of the iI patients reoperation for cataract in the 'quadrantic loss' and who underwent cataract extraction experienced a the central island groups is in the order of 30 great improvement in visual function (Table III;

per cent within the periods of final review. The Patients 2, 3, 6, 8, IO, and 13). Two aphakic eyes http://bjo.bmj.com/ risk of a maculopathy for the residual central island (4, iI) are contributing to binocularity, and two group is in the region of I2x5 per cent within 6 (5, 7) are held in potentially useful reserve. months (Tables I and II). When cataracts develop in patients with glaucoma If the 5-year survival of macular function is simplex who are under ophthalmic care their improved only from 75 to 83 per cent by drainage management is easier. The history of the visual surgery (Kronfeld and McGarry, 1948), these acuity and the visual fields will usually indicate if sequelae of surgery would not be justified. However, macular function is likely to be present, as dis- Kronfeld and McGarry did not describe the cussed already. on September 26, 2021 by guest. Protected amount of lowering of intraocular pressure achieved When patients present with advanced cataracts medically in their unoperated group and this may and late glaucoma (Patients 9 to 13, Table III) it have more significance regarding survival of the may be impossible to determine the status of visual field than 24-hour control under the arbitrary macular function. Thus in four of these five patients, pressure of 2i mmHg (Miller and Karseras, 1974). pinhole vision, Maddox rod testing, entoptic In cases in which medical therapy has little thera- imagery, and testing the perception of two approxi- peutic effect on high intraocular pressures and mated coloured lights did not indicate the presence reasonable longevity is assumed, the risks of of macular function. Perimetric field analysis is surgery may be considered to be justified in patients too refined a technique to determine the visua 1 with advanced glaucoma. fields. If vision is capable of registering hand move- The results of cataract extraction show that IO of ments this visual stimulus to confrontation in the I3 patients had an improved visual acuity, maculo- four quadrants has been found to be the most pathy being responsible for postoperative morbidity useful in determining the extent of glaucomatous in three patients. field loss. If visual fields are full to confrontation Lawrence (I969) carried out eight cataract macular function is invariably present despite extractions in eyes with macular function and this possible central Bjerrum scotoma. It is rare for was retained in six patients (three central islands central vision to be lost subsequent to a quadrantic Br J Ophthalmol: first published as 10.1136/bjo.60.2.124 on 1 February 1976. Downloaded from Intraocular surgery in advanced glaucoma 131

defect (Patient 12, Table III) and it is often re- Out of 69 intraocular procedures (46 drainage tained in the presence of a nasal hemianopic operations, I3 cataract extractions) two patients defect (Table III, Patients io and iI). Such glau- lost central visual field subserving macular fixation comatous field defects, when associated with possibly as a result of surgery. advanced cataract, do not preclude potential There is an increased incidence of postoperative macular function. This was attained in three out of maculopathy in late glaucoma. Three drainage five eyes in these circumstances (Table III, Patients operations out of 46 and four cataract extractions 10, II, 13). It is rare to make such patients' vision out of I3 had this complication. worse, so that reversibility of visual loss may be Altogether 30 per cent of drainage procedures excluded by cataract extraction when the patient's induced deterioration of visual acuity of lenticular binocular visual status and life situation merit it. origin to a level normally requiring cataract extrac- tion. Trabeculectomy was found to be less likely to cause this sequela than the Scheie procedure at Summary the 6 month postoperative stage. However, 77 per Loss of visual field subserving macular function cent of patients with advanced glaucoma and has been found to be rare after intraocular surgery cataract obtained a satisfactory improvement in in advanced glaucoma. Abrupt changes in refrac- visual status after cataract extraction. tive error, lens opacity, and suppression must be carefully excluded before macular fixation is We should like to thank M. V. Graham, P. Graham, deemed lost. and P. V. Mills for permission to study their patients.

References

BLOOMFIELD, S., and KELLERMAN, L. (1949) Amer. J. Ophthal., 32, 1177 copyright. FANTA, H., and HEROLD, I. (i966) Klin. Mbl. Augenheilk., x48, 834 KRoNFELD, P. c., and McGARRY, H. I. (1948) J. Amer. med Ass., I36, 957 LAWRENCE, G. A. (I969) Arch. Ophthal., 8I, 8o4 LICHTER, P. R., and RAVIN, J. G. (1974) Amer. Y. Ophthal., 78, I009 MILLER, S. J. H., and KARSERAS, A. G. (I974) Brit. Y. Ophthal., 58, 455 NEMETZ, U. R., and PAPAPANOS, G. (I959) Klin. Mbl. Augenheilk., I34, 83 http://bjo.bmj.com/ on September 26, 2021 by guest. Protected