Brit. Y. Ophthal. (1976) 6o, 287

Pigmented lens striae

GEORGE D. STURROCK AND RAMESH C. TRIPATHIFrom Moorfields Eye Hospital and the Department of Pathology,Institute of Ophthalmology (University of London), Judd Street, London

In his atlas of slit-lamp microscopy of the eye

Vogt (I93i) described an unusual condition offine brown radial lines on the anterior lens capsulein the mid-periphery behind the iris. Becausepupillary membrane remnants were present inthree patients he concluded that the striae repre-

sented persistent tunica vasculosa lentis-a viewsupported by Lugli (I933), Streiff (I935), Bischler(1939), Vogt (1942), and Bellows (i944) when

reporting further examples of this condition.Cowan (I96I), however, suggested that some cases

of 'retroiridic lines' might represent congenitaldeposition of pigment on zonular fibres. In theabsence of any histological study, the precisenature of the pigmented lens striae remainedunresolved.

During the past two years one of us (GDS) saw a

number of patients with these pigmented lens striae.Since their morphology and distribution seemedinconsistent with a diagnosis of persistent tunicavasculosa lentis we examined three of the lenses byelectron microscopy. This paper correlates for thefirst time the clinical with the ultrastructuralfeatures of pigmented lens striae.

Patients and methodsPigmented striae on the anterior lens capsule were

seen in six women and one man aged between 5 and87 years. Two of the patients had chronic glaucoma,one had a retinal hole, and four were in hospital forcataract surgery. The lenses from three of the patientswith cataracts were processed for examination byelectron microscopy.

In the first patient chymotrypsin was used to dissolvethe zonule before removal of the lens. The lenses of theother two patients were extracted without the use ofthis enzyme. The lens in one case was delivered withcapsule forceps, taking care to grasp the capsule some

distance away from the previously determined positionof the pigmented striae. In the third patient the lenswas removed with a cryoprobe, purposely freezing on tothe capsule at the site where striae had been notedpreoperatively.The extracted lenses were fixed immediately in

Address for reprints: Dr R. C. Tripathi, Institute of Ophthal-mology, Judd Street, London WCiH 9QS

isotonic buffered glutaraldehyde (2 5 per cent solution)The pigmented striae were identified under a dissectingmicroscope, tissue blocks were postfixed in i per centbuffered osmium tetroxide solution and, after dehydra-tion, were finally embedded in Araldite. Using glassknives, sections were cut on an LKB Ultratome III atabout right-angles to the long axis of the striae. Thinsections were stained with uranyl acetate and leadcitrate and micrographs were taken with a JOEL iooCelectron microscope.

ResultsIn all seven patients the pigmented striae could beseen only when the pupil was dilated. They weresituated on the anterior lens capsule in the mid-periphery, predominantly on the nasal side (Fig. i).Although arranged in a basically radial manner,some striae forked at an acute angle (Fig. 2). Thenumber of striae visible varied from only three orfour in some patients to several dozen in others.Individual striae appeared as very fine straightlines of uniforn width a millimetre or more inlength. In two patients with pigment speckling ofthe anterior lens capsule some striae had a beadedappearance due to small deposits of pigmentedparticles. Most striae were dark brown in colourin focal illumination, although in one patient finetranslucent grey striae were also visible.The three extracted lenses were examined under

a dissecting microscope. No striae could be foundon the lens which was extracted after irrigation ofthe posterior chamber with chymotrypsin. Striaewere seen, however, on the two lenses removedwithout the use of chymotrypsin (Fig. 3).

Analysis by electron microscopy showed thatthe pigmented striae consisted of variable-sized,electron-dense, round or oval granules entrappedin bundles of fine fibrils. Sections along the lengthof the striae showed that near their terminationthe fibrillar bundles were in close contact with thelens capsule (Fig. 4) whereas peripherally they wereseparated from the surface of the lens capsule(Fig. 5). The fibrillar bundles were composed ofnumerous fine filamentous structures cut trans-versely or obliquely; the individual fibrils variedfrom I2-I5 nm in diameter and had a faint axial

on March 9, 2021 by guest. P

rotected by copyright.http://bjo.bm

j.com/

Br J O

phthalmol: first published as 10.1136/bjo.60.4.287 on 1 A

pril 1976. Dow

nloaded from

288 British Journal of Ophthalmology

FIG. I Painting to show radialdisposition of pigmented striae onmid-periphery of anterior lens capsule.Pigment speckling also visible in sameregion. Right eye of woman aged 70with chronic simple glaucoma andshallow anterior chamber

periodicity of 20-25 nm (Fig. 6). The electron-dense pigment granules were irregularly dispersedalong the fibrillar bundles, and at higher magnifi-cation appeared to consist of finely particulate oramorphous material and occasional granules showedfibrillar profiles (Fig. 6). No cell organelles wereseen in relation to these granules.

Discussion

A review of the 70 reported cases of pigmentedlens striae shows that they occurred most often inmiddle-aged and elderly patients, of whom 8oper cent were women. Except for a girl aged I7(Vogt, 1942) and a young man of 27 (Bellows,1944), the 70 patients were aged between 40 and87 year. The striae were bilateral in over half thecases, although more pronounced in one eye.Most authors have commented on the predomi-nantly na,al disposition of the striae, which re-mains unexplained.The older-age incidence of pigmented lens

striae Itrongly suggests that the pigmentation isacquired, the most likely source being the pigmentlayer of the iris. In support of this is the observationthat when the pupil can be dilated sufficientlypigmented lines are often seen to terminate before

reaching the extreme periphery of the lens, which,owing to its backward curvature, is not usually incontact with the iris. Examination of the lens infour patients with congenital aniridia showed nosign of pigmented lens striae (Iwaszkiewicz-Bilikiewiczowa and Janukowiczowa, I969).

In many of the reported cases of pigmentedlens striae there was evidence of generalized pig-ment dispersion in the anterior segment. Lugli(I933) mentioned pigment deposition on Desce-met's membrane in a patient with iris atrophyand pigmented lens striae, and Bischler (I939)described pseudoexfoliation (commonly associatedwith pigment dispersion) in one patient with pig-mented lens striae and a Krukenberg spindle in asecond patient. Stankovic and Stankovic (I962)noted much pigmentation of the trabecular mesh-work and raised intraocular pressure (withoutfield loss) in nine out of 14 patients with pigmentedlens striae, none of whom had pseudoexfoliationor a Krukenberg spindle.The illustrations of Vogt (I 93 I) of pigmented lens

striae also show non-pigmented, greyish translucentstriae in some of his patients. Similar non-pig-mented striae were described by Lugli (I933),Bischler (I939), Bellows (I944), and Berliner(I949) in patients with pigmented lens striae, and

on March 9, 2021 by guest. P

rotected by copyright.http://bjo.bm

j.com/

Br J O

phthalmol: first published as 10.1136/bjo.60.4.287 on 1 A

pril 1976. Dow

nloaded from

Pigmented lens striae 289

they were also seen in one of the seven patientspresented here. These grey striae resemble thecondition called Strahlenkranztrubung originallydescribed in glass-workers by Schlapfer (1930)and Vogt (1931). Subsequently Abramowicz (I933)and Bucklers (i939) found the same condition in ahigh proportion (90 per cent and 72 per centrespectively) of patients not engaged in glassmakingor foundry work.The grey striae of Strahlenkranztrubung are not

visible in the zone of specular reflection from theanterior surface of the lens, and were thereforeassumed to be subcapsular by Vogt (1931),Abramowicz (I933), and Biucklers (I939), who didnot relate them to pigmented lens striae. Abramo-wicz (I933), however, found pigmented lens striaeassociated with grey striae in one patient and inanother noted that an incomplete ring of greystriae, concentric with the pupil, was interruptedonly at the site of an iridectomy performed 13years previously for glaucoma. Bischler (1939)recorded the almost total disappearance of bilaterallens striae, some grey-blue and some pigmented,after bilateral iridencleisis procedures performedin a woman of 66. In both of these patients intra-ocular surgery may have disturbed their lensstriae, suggesting that the non-pigmented striaewere, like the pigmented lens striae, situated on thesurface of the capsule. Bischler also described thespontaneous disappearance of well-marked pig-mented lens striae I5 months after they were firstobserved in a woman of 45 who presented withpresbyopia. Possibly, therefore, the grey striae ofStrahlenkranztriibung are similar in nature to thenon-pigmented striae sometimes associated withpigmented lens striae.

Electron microscopical analysis clearly showsthat pigmented lens striae are formed by pigmentgranules trapped within the fibrillar bundles of thezonules. The absence of any other cellular compo-nents associated with the pigment granules sug-gests that they entered the zonular bundles asfree-floating pigment and were probably notdeposited by wandering cells or elaborated locally.The morphological appearance of the granulesseems consistent with an origin from the uvealtract, the pigment layer of the iris being the mostlikely source (Feeney, Grieshaber, and Hogan,I 965).Pigmented lens striae can be differentiated

clinically from conditions such as 'persistent pupil-lary membrane', posterior synechiae showing aspigmented streaks after mydriasis, and pseudo-exfoliation associated with pigment dispersion.The mesodermal strands of a 'persistent pupillarymembrane' are much coarser than pigmented lensstriae and rarely have a strictly radial orientation.The strands, which may be multiple to form a net-

FIG. 2 Slit-lamp photograph of pigmented lens striaenear margin of dilated pupil (white zone). Note acuteforking of some striae. Left eye with retinal hole ofman aged 66. ( - x 8o)

FIG. 3 Macrophotograph of extracted lens showingpigmented stria which forks (arrow) at insertion intoanterior lens capsule. Epithelial cells and lens fibresvisible in the background. ( t x 70)

like pattern, are almost invariably attached to theiris collarette. Mydriasis commonly alters thedisposition of pupillary strands since they areusually distensible and stretch with the pupil.Pupillary strands may coexist with pigmented

A-1 A-0, t8

on March 9, 2021 by guest. P

rotected by copyright.http://bjo.bm

j.com/

Br J O

phthalmol: first published as 10.1136/bjo.60.4.287 on 1 A

pril 1976. Dow

nloaded from

290 British Journal of Ophthalmology

.Y .i.Jrn. 1.

FIG. 4 Electron micrograph of pigmented lens stria in section near attachment to lens capsule (LC). Stria consistsof fine fibrils (cut transversely and obliquely) with characteristics of fibrils of zonular bundles. P= trapped pigmentgranules. (Fixed GA/sO04, stained UA/LC. x 6o ooo)

on March 9, 2021 by guest. P

rotected by copyright.http://bjo.bm

j.com/

Br J O

phthalmol: first published as 10.1136/bjo.60.4.287 on 1 A

pril 1976. Dow

nloaded from

Pigmented lens striae 291

9

re: 6ljV, II

e

.it

5

FIG. 5 Electron micrograph of pigmented lens stria in section at region peripheral to attachment showing spatialrelationship of stria with lens capsule (LC). Note numerous pigment granules (P) entrapped by the fibrillarcomponent of the stria. (Fixed GA/OsO4, stained UA/LC. x 22 8oo)

1.

" .T,.-. .-:o0, .f V .k:r,; li.i?!. . .-,f

"u. ia.,

,4"

* .tPI

..s..,0 ..'01

on March 9, 2021 by guest. P

rotected by copyright.http://bjo.bm

j.com/

Br J O

phthalmol: first published as 10.1136/bjo.60.4.287 on 1 A

pril 1976. Dow

nloaded from

292 British Journal of Ophthalmology

V . : ...... . - . ....A,;.4*.S r i F AS w j^ r4...* s

&:.. .

FIG. 6 Higher magnification of pigmented lens stria in section. Note some variati6n in morphology of pigmentgranules (P) and characteristic fine fibrils of zonule. Variable orientation of fibrils probably due to relaxed state ofthe bundle. (Fixed GA/Os04, stained UA/LC. x 67 500)

p -. ..::_w. .*-::..-

r. "

., ":, H: '.:.i!c,:. In t.

4t.

i.*-

on March 9, 2021 by guest. P

rotected by copyright.http://bjo.bm

j.com/

Br J O

phthalmol: first published as 10.1136/bjo.60.4.287 on 1 A

pril 1976. Dow

nloaded from

Pigmented lens striae 293

lens striae as in three of Vogt's cases (Vogt, I93 I).The pigmented streaks of posterior synechiae

are situated more centrally on the lens than pig-mented lens striae and are attached to the pupilmargin. They are also much broader than striaeand their postinflammatory origin is usually evi-dent.The diagnosis of pseudoexfoliation is suggested

by the presence of blue-grey floccules on the pupilmargin and confirmed by dilating the pupil toreveal the characteristic peeling sheets of pseudo-exfoliative material on the lens surface with anannular clear zone corresponding to the restingposition of the pupil. Pseudoexfoliation may alsocoexist with pigmented lens striae (Bischler, I939).Ultrastructurally there is little doubt that the finefibrillar bundles analysed in specimens belong tothe zonular system (Hogan, Alvarado, and Weddel,I971; Raviola, 1971; Takei and Ozanics, 1975),and they could be differentiated from the coarseand haphazardly arranged collagenous fibrils ofpupillary membranes (Matsuo and Smelser, 1971).Pigmentation of zonular fibres on the anterior lens

capsule renders them visible with the biomicro-scope and also shows that some fibres are insertedmore centrally on the anterior lens capsule than iscommonly described (Duke-Elder, 196I).

SummaryThe clinical features of pigmented lens striae werestudied biomicroscopically in seven patients. Thelenses of three of these, obtained by cataractsurgery, were examined by electron microscopyto determine the structure of the striae. We con-cluded that the striae are not formed by remnantsof tunica vasculosa lentis, as earlier workersbelieved, but consist of fine fibrils of zonularbundles entrapping pigment granules of uvealorigin.

We thank Professor N. Ashton, FRS, Mr D. Greaves,FRCS, and Mr. R. J. H. Smith, FRCS, for theirencouragement and Mr R. Howes for his technicalassistance. This work was supported in part by thelocally organized clinical research scheme of MoorfieldsEye Hospital.

References

ABRAMOWICZ, I. (I933) Ann. Oculist. (Paris), 95, 602BELLOWS, J. G. (I944) Arch. Ophthal., 32, 483BERLINER, M. L. (1949) 'Biomicroscopy of the Eye', vol. 2. Hoeber, New YorkBISCHLER, V. (1939) Klin. Mbl. Augenheilk., 103, 517BUCKLERS, M. (I939) Ibid., 103, 4I3COWAN, T. H. (I96I) Surv. Ophthal., 6, 630DUKE-ELDER, S. (I96i) 'System of Ophthalmology', vol. 2, p. 335. Kimpton, LondonFEENEY, L., GRIESHABER, j., and HOGAN, M. J. (I965) 'Studies on Human Ocular Pigment', Eye StructureSymposium II, ed. J. W. Rohen, pp. 535-548. Schattauer, Stuttgart

HOGAN, M. J., ALVARADO, J. A., and WEDDEL, J. E. (I971) 'Histology of the Human Eye'. Saunders,Philadelphia, London, Toronto

IWASZKIEWICZ-BILIKIEWICZOWA, B., and JANUKOWICZOWA, H. (I969) Klin. oczna, 39, 693LUGLI, L. (I933) Rass. ital. Ottal., 2, 1334MATSUO, N., and SMELSER, G. (1971) Invest. Ophthal., 1O, io8RAVIOLA, G. (1971) Ibid., IO, 85ISCHLXPFER, H. (I930) Klin. Mbl. Augenheilk., 85, 285STANKOVIC, M., and STANKOVIC, I. (I962) Bull. Soc. fran. Ophtal., 75, 586STREIFF, E. B. (1935) Indagine biomicroscopica sui residui delle tunica vascolare retroiridea del cristallino.

Atti del XXXIII congr. della Soc. Oftal. Ital., p. 89.TAKEI, Y., and ozANics, v. (I975) Jap. J. Ophthal., I9, 69VOGT, A. (193 I) 'Lehrbuch u. Atlas der Spaltlampenmikroskopie des lebenden Auges', vol. 2, 2nd ed.

Springer, Berlin(T942) 'Lehrbuch u. Atlas der Spaltlampenmikroskopie des lebenden Auges', vol. 3, 2nd ed. Enke,

Stuttgart

on March 9, 2021 by guest. P

rotected by copyright.http://bjo.bm

j.com/

Br J O

phthalmol: first published as 10.1136/bjo.60.4.287 on 1 A

pril 1976. Dow

nloaded from