somewhat extreme, the amount of hyperopic shift seenin our patient suggests that this represents an ‘‘outlier,’’as cited in previously performed studies.9 Given thesedata, one needs to wonder how much hyperopic shiftseen in post-RK eyes is actually caused by RK10 com-pared with that which occurs naturally with age.

This patient may be an extreme event in biology;however, we definitely have the impression that thereare hyperopic changes apparent in our patient popula-tions, as noted in previous studies,9 in the fifth andsixth decades of life. Since this is a general phenome-non, we should see these changes in the long-termfollow-up of non-RK corneal refractive procedures. Itis hypothesized that these changes are due to age-related progressive changes in ciliary muscle tone.11

Therefore, one unavoidable conclusion would be thatrefractive surgery that replaces the crystalline lenscould uniquely avoid this variable and unpredictablephenomenon. If loss of ciliary tonicity causes a netloss in the dioptic power of the crystalline lens due toa change in the lens shape, one would expect that sim-ply replacing the crystalline lens with a conventionalintraocular lens (IOL) would prevent this hyperopicshift. However, if the change in tonicity is associatedwith a positional change of the crystalline lens, thehyperopic shift would persist even with the lensexchange and an adjustable IOL would be requiredfor refractive stability.12

REFERENCES1. Kymionis GD, Tsiklis N, Pallikaris AI, et al. Long-term results of

superficial laser in situ keratomileusis after ultrathin flap crea-

tion. J Cataract Refract Surg 2006; 32:1276–1280

2. Rajan MS, O’Brart D, Jaycock P, Marshall J. Effects of ablation

diameter on long-term refractive stability and corneal transpar-

ency after photorefractive keratectomy. Ophthalmology 2006;

113:1798–1806

3. CharpentierDY, GarciaP,Grunewald F,etal.Refractive resultsof

radial keratotomy after 10years. JRefractSurg1998;14:646–648

4. Waring GO III, Lynn MJ, McDonnell PJ. Results of the Prospec-

tive Evaluation of Radial Keratotomy (PERK) Study 10 years af-

ter surgery; the PERK Study Group. Arch Ophthalmol 1994;

112:1298–1308

5. Deitz MR, Sanders DR, Raanan MG. Progressive hyperopia in

radial keratotomy; long-term follow-up of diamond-knife and

metal-blade series. Ophthalmology 1986; 93:1284–1289

6. Randleman JB, Caster AO, Banning CS, Stulting RD. Corneal

ectasia after photorefractive keratectomy. J Cataract Refract

Surg 2006; 32:1395–1398

7. Tabbara KF, Kotb AA. Risk factors for corneal ectasia after LA-

SIK. Ophthalmology 2006; 113:1618–1622

8. Werblin TP, Stafford GM. The Casebeer system for predictable

corneal refractive surgery; one year evaluation of 205 consecu-

tive eyes. Ophthalmology 1993; 100:1095–1102

9. Hirsch MJ. Changes in refractive state after the age of forty-five.

Am J Optom Arch Am Acad Optom 1958; 35:229–237

10. Werblin TP, Stafford GM. Hyperopic shift after refractive keratot-

omy using the Casebeer System. J Cataract Refract Surg 1996;

22:1030–1035

11. Walton WG Jr. Refractive changes in the eye over a period

of years. Am J Optom Arch Am Acad Optom 1950; 27:

267–286

12. Werblin TP. Why should refractive surgeons be looking beyond

the cornea? The Barraquer Lecture. J Refract Surg 1999;

15:357–376

1344 CORRESPONDENCE

J CATARACT REFRACT SUR

Intraocular pressure rise and recurrenceof capsular block syndrome afterneodymium:YAG laser anterior capsulotomy

Ahmet Colakoglu, MD, Necmettin Kucukakyuz, MD,Iffet E. Topcuoglu, MD, Solmaz Akar, MD, PhD

Capsular block syndrome (CBS) occurs when thecontinuous curvilinear capsulorhexis (CCC) marginis occluded by the intraocular lens (IOL) optic.1,2 Wereport a case of intraocular pressure (IOP) rise andrecurrence of capsular bag distension after neody-mium:YAG (Nd:YAG) laser anterior capsulotomyperformed for late postoperative CBS with opaquecontents.

CASE REPORT

An 85-year-old man, who had had cataract extractionwith phacoemulsification and IOL implantation in theright eye 6 years earlier, presented with a complaint ofblurred vision in the right eye, with a best corrected vi-sual acuity (BCVA) of 20/800. Slitlamp examinationshowed a circumferential adhesion between the mar-gin of the anterior capsule opening and the anteriorsurface of the peripheral IOL optic and mild posteriorcapsule opacification (PCO). There was a pool of ho-mogeneous milky-white fluid between the posteriorsurface of the IOL optic and the posterior capsule.White fragments of moderate size were also observedin the capsular bag, but the optical axis was free ofthese fragments. The posterior capsule was vaultedposteriorly. No cells or flare were observed in the an-terior chamber, and no abnormalities were observedin the cornea, vitreous body, or retina. The milky-white substance in the pocket was thought to be themain cause of the reduced vision, aside from themild PCO, and a posterior capsulotomy was sched-uled to eliminate the substance.

The aiming beam of the Nd:YAG laser could not befocused on the posterior capsule because of the intenseopacity of the contents in the hyperdistended capsularbag. Surgical drainage of the turbid fluid via the parsplana approach was proposed, but the patient de-clined. He accepted the anterior capsulotomy alterna-tive. Wide dilation of the pupil was achieved to exposethe anterior capsule at the 6 and 12 o’clock positions.Inferior and superior anterior capsulotomies were per-formed beyond the edge of the IOL using a Nd:YAG

G - VOL 33, JULY 2007

1345CORRESPONDENCE

laser. Turbid fluid with minute white fragments wasemptied from the capsular bag anteriorly into the ante-rior chamber, and the distended capsule was restoredexcept in areas with large white fragments. Brimoni-dine and topical dorzolamide 2%, timolol 0.5% oph-thalmic solution, dexamethasone eyedrops, and 1tablet of acetazolamide were prescribed. On the morn-ing of the laser anterior capsulotomy, the IOP was65 mm Hg on applanation tonometry. Topical treat-ment and systemic acetazolamide continued with theaddition of intravenous mannitol 20%. The milky-white fluid continued to completely fill the anteriorchamber the next morning, accompanied by an IOPof 50 mm Hg and corneal edema.

Two days post capsulotomy, the turbidmedium fill-ing the anterior chamber was removed via bimanualirrigation/aspiration (I/A) under sub-Tenon’s anes-thesia. The contact margin between the IOL and theanterior capsule was freed from adhesion with the as-piration instrument, and the retrolental pocket was en-tered. Removal of the retrolental cortex-like materialand the milky-white fluid was attempted by vigorousI/A, but some of the white fragments remained.

On the day after the procedure, the IOPwas reducedto 7 mmHg. At 8 days, it was 10 mmHgwithout anti-glaucomatous medication. At 3 weeks, the BCVA im-proved to 20/300. The patient was satisfied with theimprovement in vision and rejected a posterior capsu-lotomy. At the 1-month visit, capsular distension wasseen to recur, with an IOP of 10 mm Hg and cloggingof the anterior capsulotomy opening. A posterior cap-sulotomy was performed immediately. The turbidfluid was emptied from the capsular bag posteriorlyinto the vitreous after the Nd:YAG laser capsulotomy,and the distended capsule was restored. One day post-operatively, the BCVA was 20/180 and the IOP was11 mm Hg.

DISCUSSION

Liquefied after-cataract is reported to be a specific typeof after-cataract in which the CCC edge adheres to theIOL optic around the entire edge of the opening anda liquid substance accumulates in the closed chamberformed between the IOL optic and the posterior cap-sule. The IOL optic occluding the capsulotomy open-ing formed in CCC is common in type 1 CBS, whichis defined as late CBS.

Thecondition inourpatientwouldbeclassifiedas latepostoperative CBS according to the Miyake et al. classi-fication.2 Fibrosis is produced along the CCC openingand is adherent to the optic of the IOL fixated in the cap-sular bag. In our patient, closure of the capsular bagwasinduced by completely sealing the anterior capsuleopening against the posterior surface of the IOL optic.

J CATARACT REFRACT S

The mechanism responsible for this syndrome resultedfrom residual lens epithelial cells (LECs) undergoingmetaplasia and proliferation, producing numeroustypes of collagen and extracellular substances that even-tually accumulated in the capsule. This contributed tohigher osmolarity, allowing the aqueous humor to per-meate and collect inside the capsule.3

The substance in the distended bag was identical tothat in previous reports.2–5 The main part of the lique-fied material appeared to be an aggregation of varioustypes of collagen and extracellular matrix (ECM) pro-duced by residual LECs through a process of pseudo-metaplasia, proliferation, or an aggregation of lensprotein such as albumin or a-crystalline, as reportedby Eifrig.5

In our case, many residual lens remnants werefound. The areas in which the remnants were locatedwere surrounded by the accumulated milky-whitesubstance. An anterior Nd:YAG capsulotomy may ex-pose the anterior chamber to an acute release of milky-white fluid containing collagen and ECM that may bedifficult to drain via the trabecular meshwork becauseof clogging and high osmolarity, potentially elevatingthe IOP. In addition, wide dilation of the pupil is neces-sary to prevent the peripheral anterior capsulotomyfrom damaging the lens optic. In this case, an IOP riseunresponsive to medical management followed ante-rior capsulotomy. We decided to remove the turbidfluid and white matter from the anterior chamber asearly as possible based on the results reported in casesof retained lens fragments.6 Landa et al.7 observed nocase of ocular hypertension after posterior capsulotomyin late CBS with PCO.

Reformation of the milky-white fluid may occur af-ter a short period following anterior capsulotomy inlate CBS without posterior capsulotomy. Intraocularpressure rise should be considered in patients havingan Nd:YAG laser anterior capsulotomy for late post-operative CBS. Posterior but not anterior capsulotomymay be a safer procedure for the treatment of late CBS.Posterior drainage of the turbid fluid would avoid therisk for IOP rise, as reported by Landa et al.7 If a safeNd:YAG posterior capsulotomy is not feasible becauseof technical reasons, surgical aspiration of the turbidfluid followed by posterior capsulotomy with preser-vation of the anterior capsule–IOL barrier might be of-fered as an alternative.

REFERENCES1. Davison JA. Capsular bag distension after endophacoemulsifica-

tion and posterior chamber intraocular lens implantation. J Cata-

ract Refract Surg 1990; 16:99–108

2. Miyake K, Ota I, Ichihashi S, et al. New classification of capsular

block syndrome. J Cataract Refract Surg 1998; 24:1230–1234

URG - VOL 33, JULY 2007

1346 CORRESPONDENCE

3. Miyake K, Ota I, Miyake S, Horiguchi M. Liquefied aftercataract:

a complication of continuous curvilinear capsulorhexis and intra-

ocular lens implantation in the lens capsule. Am J Ophthalmol

1998; 125:429–435

4. Ota I, Miyake S, Miyake K. [Whitish liquefied aftercataract: a pre-

liminary report.] [Japanese] Ganka Shujutsu 1997; 10:353–357

5. Eifrig DE. Capsulorhexis-related lacteocrumenasia. J Cataract

Refract Surg 1997; 23:450–454

J CATARACT REFRACT S

6. Vilar NF, Flynn HW Jr, Smiddy WE, et al. Removal of retained

lens fragments after phacoemulsification reverses secondary

glaucoma and restores visual acuity. Ophthalmology 1997; 104:

791�791; discussion by HR McDonald, 791�792

7. Landa G, Hoffman P, Pollack A, et al. Outcome of posterior

capsulotomy in late capsular block syndrome with posterior

capsular opacification. Clin Exp Ophthalmol 2006; 34:

866–869

URG - VOL 33, JULY 2007