British Journal of Ophthalmology, 1979, 63, 465-468

Cataract extraction complicated by capsular glaucomaANTHONY J. DARKFrom the Department of Ophthalmology, Veterans Administration Hospital, Syracuse, Newv York, USA

SUMMARY Synechiae involving the iris pigment epithelium and the peripheral anterior lens capsuleoccur in capsular glaucoma. During cataract extraction they may bring about traction on thecapsule threatening its rupture. The ultrastructural basis of these adhesions is a bonding of pigmentcells to capsular surface by pseudoexfoliative material.

Tarkkhanen (1962) noted that the incidence ofsenile cataract in patients with unilateral pseudo-exfoliation (PE) was no greater on the affected thanthe unaffected side. He concluded that PE diseasedoes not appear to be pathogenically associated withcataract. In contrast, patients with capsular glaucomahave a high incidence of lens opacities. Layden andShaffer (1974) suggested that some of these cataractsmay be iatrogenic as many of these patients havebeen subjected to filtration procedures and long-acting anticholinesterases.

Capsular glaucoma affected about 50% ofTarkkhanen's (1962) patients with the PE syndrome.The mechanism producing capsular glaucoma isunknown. Since steroid responses are positive inmore than 28% of patients (in contrast to the 90%seen in chronic simple glaucoma), Pohjola and Hors-manheimo (1971) considered it to be secondary tothe PE process. Support for this contention wasprovided by the transmission electron microscopic(TEM) studies of Ringvold (1971), who found PEmaterial both within and between the trabecularbeams of the meshwork and, perhaps more signi-ficantly, infiltrating the juxtacanalicular connectivetissue as well as within the giant vacuoles of theendothelial cells lining the proximal wall ofSchlemm's canal.

It is well known that adequate mydriasis is difficultto obtain in PE disease, a circumstance which isprobably due to the extensive infiltration of theiris with PE fibres, as was noted by Ghosh andSpeakman (1974). These authors found PE materialembedded in the anterior limiting layer, surroundingand even replacing the radial blood vessels as wellas being deposited on and between the basementmembrane of the iris and pigment epithelium. Thereis a special tendency for PE fibres in this latter site

Address for reprints: Dr Anthony J. Dark, MD, Depart-ment of Ophthalmology, Veterans Administration Hospital,Syracuse, New York 13210, USA

to accumulate in the circumferential furrows, wherethey compress the intervening epithelial ridges,producing a striped appearance macroscopicallyand a characteristic cogwheel outline in radialmicroscopic sections as noted by Yanoff and Fine(1975). PE material in this location may causeadherences of the iris to the peripheral lens capsule.Aasved (1973) found fragments of the pigmentlayer on the anterior lens capsule in such cases, andthe 'remnants of posterior synechiae' which Krauseand Tarkkhanen (1978) observed in 5 out of 100extracted cataractous lenses affected with PE diseaseare presumably further evidence of this type ofadhesion.The nature, extent, and tensility of this bonding

of the iris to the periphery anterior lens capsule incapsular glaucoma (and to a less extent in PEdisease) has not been the subject of previous com-ment. The following report describes the histologyof these adhesions and indicates that they are apotential cause of capsule rupture when cataractextraction is undertaken.

Material and methods

Six eyes of 6 consecutive patients with capsularglaucoma were operated on for cataract. Five ofthe patients had been treated with anticholinesterasesfor control of glaucoma. Radial iridotomies orsphincterotomies were performed to enlarge thepupil. Alpha-chymotrypsin was used in all cases.The extracted lenses were fixed in cold 2%glutaraldehyde. Selected specimens of pre-equatoriallens capsule were osmified, dehydrated, andembedded in epoxy resin before sectioning for TEM.

Results

Preoperative mydriasis in the eye scheduled forcataract extraction was limited to 5 mm or less in

465

on Decem

ber 23, 2020 by guest. Protected by copyright.

http://bjo.bmj.com

/B

r J Ophthalm

ol: first published as 10.1136/bjo.63.7.465 on 1 July 1979. Dow

nloaded from

the pigment epithelium of the iris periphery whichcorresponded in size and position with the pigmentsheets adherent to the extracted lenses.An extensive bonding of the iris pigment epithel-

ium to the pre-equatorial lens capsule by PE fibreswas confirmed in TEM (Fig. 3). There was noevidence of collagenous or other fibrous union. Cellmembranes of the pigment epithelial cells were oftendisrupted with PE fibres Iying alongside various

ni~~~ organelles. In these areas the basement membraneof the iris was also frequently absent. Occasionallybush-like excrescences of PE fibres were capped with

fa ruptured pigment cells (Fig. 4). The lens capsule...........~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~...................often showed surface irregularities and multilaminarbasement membrane formation (Fig. 3) as well as

- the pathognomonic deep striated band described byBertelson et al. (1964).

Discussion

_ 't ' & Impaired mydriasis in patients with senile cataractsmay be associated with the PB syndrome. Neverthe-

.......

Figs. 1 (a), (b) Sheets of iris pigment epithelium, P, areadherent to the pre-equatorial lens capsule. Zonules, Z,are encrusted with PE material. Cases 1 and 2

2aevery case. Neither iridodonesis nor phakodonesiswas noted in any of these patients. Cataract extrac-tion in all of the patients was protracted and thecapsule thrown into traction folds until the lenswas .finally delivered. The extracted lenses showed 1 to 4sheets of iris pigment epithelium which wereattached to the anterior lens capsule in the pre-........equatorial region (Figs. 1 and 2). In some instancesnthe pigment sheets were rolled over, the posterior 1

iridic surfaces showing the characteristic stripingcaused by PB fibres accumulated within the circularfurrows (Fig. 2). Elsewhere in the pre-equatorialregion and to a less extent in the granular zone therewas a fine pigment stippling. Pigment granules oftenadhered to and defined the zonules,, which moreperipherally were encrusted with PE material. Somezonules were stiffened and stood out from the Fig. 2 (a) Iris pigment epithelial sheet adheres tocapsule at an acute angle for a millimetre or so. capsule, but it is rolled over to display striped appearance

Transpupillary transillumination of the irides caused by accumulation ofPE fibres in circumferentialpostoperatively showed sharply defined defects in furrows. Case 3. (b): Detail of2 (a)

Anthony J. Dark466

I I I I

on Decem

ber 23, 2020 by guest. Protected by copyright.

http://bjo.bmj.com

/B

r J Ophthalm

ol: first published as 10.1136/bjo.63.7.465 on 1 July 1979. Dow

nloaded from

Cataract extraction complicated by capsular glaucoma

Fig. 3 Pseudoexfoliative fibres,PE, bonding iris pigmentepithelium, P, to zonules, Z, andlens capsule, C, which showsmultilaminar basement membraneformation. The basementmembrane of the pigmentepithelial cell has almostdisappeared and the cell membraneis dehiscent, so that PEfibres liein direct contact with organelles( x 10 800)

less, it is usually taught that cataract extraction inthis disorder is relatively uncomplicated. Certainlythe zonules are unduly fragile and may undergospontaneous rupture, leading to the subluxation ofthe lens in some patients, as noted by Bartholomew(1970). In contrast, the present study indicates thatcataract extraction, in spite of an adequatelyfashioned pupillary opening, may be difficult insome patients with capsular glaucoma because PEfibres often effect an extensive union of the irispigment epithelium to the pre-equatorial lensperiphery. These adhesions resist lysis with alpha-chymotrypsin. It is possible, however, that synechi-otomies may be performed by sweeping an irisrepositor between the lens and iris, a technique whichwas not used here. Peripheral bonding of the iristo the lens, together with poor dilatation of the pupilafter instillation of mydriatic, has also been reported(Zaret et al., 1976) in cataracts which developed

after exposure to non-ionising radiant energy.Moreover, difficulty in cataract extraction was alsoreported in this instance. Finally, it is well recognisedthat pigment stippling of the anterior lens capsule aswell as posterior synechiae and a poor mydriaticresponse may also be seen in patients who havebeen treated with long-acting cholinesterases forchronic simple glaucoma. The nature of theseadhesions in the 2 latter conditions has not beenstudied.Davanger (1977) views PE material as a fibre gel.

If so, aqueous could permeate the PE material onlyby the slow process of diffusion, and hence massflow would be prevented. PE material depositedbetween the lens and iris periphery may conceivablyimpede the flow of aqueous in this way, thus causinga pressure differential between the aqueous com-partments resulting in forward movement of theiris with narrowing of the angles. Herbst's (1976>

467

on Decem

ber 23, 2020 by guest. Protected by copyright.

http://bjo.bmj.com

/B

r J Ophthalm

ol: first published as 10.1136/bjo.63.7.465 on 1 July 1979. Dow

nloaded from

Anthony J. Dark

t.f k

+,

. k

:.. ^

.P

Fig. 4 Bush-like mass ofPE fibres capped bydisintegrating pigment epithelial cell ( x 8500)

patient with unilateral shallow angles and ipsilateralPE disease may have been an instance of suchhypothetical mechanics. Layden and Shaffer (1974)found that the incidence of narrow angles (grade 2or less) in 100 patients with PE syndrome was 25%in contrast to 5% of the normal population. Theseauthors point out, however, that many of their

patients were on anticholinesterases, which areknown to reduce anterior chamber depth. Thus thepossible role of these pre-equatorial adhesions inproducing angle narrowing in the PE syndromemust for the present remain speculative.

Miss Sharon Edwards was responsible for the technicalaspects of microscopy in this report.

This study was supported by a grant from the MedicalResearch Service of the Veterans Administration.

References

Aasved, H. (1973). Incidence of defects in the pigmentedpupillary ruff in eyes with and without fibrillopathiaepitheliocapsularis. Acta Ophthalmologica, 51, 710-715.

Bartholomew, R. S. (1970). Lens displacement associatedwith pseudocapsular exfoliation. British Journal ofOphthalmology, 54, 744-750.

Bertelson, T. I., Drablos, P. A., and Flood, P. R. (1964).The so-called senile exfoliation (pseudo exfoliation) ofthe lens capsule, a product of lens epithelium. ActaOphthalmologica, 42, 1096-1113.

Davanger, M. (1977). On the molecular composition andphysiochemical properties ofthe pseudoexfoliation material.Acta Ophthalmologica, 55, 621-633.

Ghosh, M., and Speakman, J. S. (1974). The iris in senileexfoliation of the lens. Canadian Journal of Ophthal-mology, 9, 289-297.

Herbst, R. W. (1976). Angle-closure glaucoma in a patientwith pseudoexfoliation of the lens capsule. Annals ofOphthalmology, 8, 853-856.

Krause, U., and Tarkkhanen, A. (1978). Cataract and pseu-doexfoliation, a clinico-pathological study. Acta Ophthal-mologica, 56, 329-334.

Layden, W. E., and Shaffer, R. N. (1974). Exoliation syn-drome. American Journal of Ophthalmology, 78, 835-841.

Pohjola, S., and Horsmanheimo, A. (1971). Topically appliedcorticosteroids in glaucoma capsulare. Archives ofOphthalmology, 85, 150-153.

Ringvold, A. (1971). Electron microscopy of the trabecularmeshwork in eyes with exfoliation syndrome. VirchowsArchiv Abteilung A. Pathologische Anatomie, 353, 110-127.

Tarkkhanen, A. (1962). Pseudoexfoliation of the lenscapsule. Acta Ophthalmologica, Supplement 71.

Yanoff, M., and Fine, B. S. (1975). Ocular Pathology: AText and Atlas, p. 365. Harper Row: Maryland.

Zaret, M. M., Snyder, W. Z., and Birenbaum, L. (1976).Cataract after exposure to non-ionising radiant energy.British Journal of Ophthalmology, 60, 632-637.

468

Vt. 'I,

on Decem

ber 23, 2020 by guest. Protected by copyright.

http://bjo.bmj.com

/B

r J Ophthalm

ol: first published as 10.1136/bjo.63.7.465 on 1 July 1979. Dow

nloaded from