Phaco-endocycloplasty: A novel technique for management of ring iridociliary cyst presenting as acute angle closure.

Iridociliary cysts of pigment epithelium are rare, ring cysts being rarer still, and usually benign in their clinical course. Presented here is a case of ring iridociliary cyst that resulted in secondary synechial angle closure with an acutely elevated intraocular pressure, refractory to medical treatment. Primary endocycloplasty and cataract extraction with implant were used successfully to manage the case.

Introduction

Iridociliary cyst of pigment epithelium has been very infrequently reported in literature, majority of which run a benign course, quite often detected incidentally and rarely causing any complications or requiring treatment.[1] Often they are solitary, but multiple cysts with pseudo-plateau appearance have also been reported.[2] Ring iridociliary cysts are rarer still and only one case of unilateral[3] and two cases of bilateral,[45] ring iridociliary cyst presenting with raised intraocular pressure (IOP) and closed angles have been reported in the literature.

Case Report

A 63-year-old female presented to emergency with a unilateral, acutely painful and red left eye of 3 weeks duration. Local ophthalmic consult diagnosed lens-induced glaucoma, and this spurred a referral to our advanced tertiary eye care institute for further management.

She was a known hypertensive, also suffering from coronary artery disease, both of which were controlled by medication. At the time of evaluation, topical treatment consisted of a single anti-glaucoma medication (AGM) (beta-blocker twice daily), anti-biotic (generic gatifloxacin thrice daily), lubricant, and hypertonic saline.

The patient was not very cooperative for examination, but persistence revealed best-corrected visual acuity (BCVA) to be count fingers at 1 m, circumciliary congestion, significant cells, and flare, raised IOP (34 mmHg), 360° synechial angle closure, and Grade II–III nuclear sclerosis. Disc examination revealed a small disc with inferior rim thinning and a cup-to-disc (CD) ratio of 0.7:1 with diffuse loss of retinal nerve fiber layer (RNFL), inferior greater than superior. BCVA of the fellow right eye was 20/80 in the presence of nuclear sclerosis of similar grade; it however had normal IOP, open angle, and healthy disc.

Unilateral presentation of synechial angle closure, with 360° open angle in the fellow right eye, excluded a diagnosis of primary angle closure glaucoma.

Differential diagnosis of unilateral secondary angle closure, considered here, included an inflammatory etiology as well as a possible neovascular one even though retinal examination failed to reveal any changes suggestive of ischemia. However, all systemic investigations (full blood count, fasting blood sugar, lipid profile, and carotid Doppler) were normal. Ultrasound biomicroscopy (UBM) [Figure 1] revealed the presence of ring iridociliary cyst in the left eye and a partial one (2 o'clock hours temporally) in the right eye.

Figure 1

Ultrasound biomicroscopy of left eye showing ring iridociliary cyst (encircled)

Maximally tolerated medical management, including topical steroids prednisolone 1%, q 2 hourly (Predforte, Allergan, Irvine, CA), cycloplegic homatropine hydrobromide 2% (Homide, Warren Excel and Warren Vision, Indoco Remedies, India), topical fixed combination of a beta-blocker, and alpha adrenergic AGM (Combigan, Allergan, Irvine, CA), and subsequently, once inflammation was brought under control, even a prostaglandin analog, bimatoprost (Lumigan 0.01%, Allergan, Irvine, CA), and oral acetazolamide (Diamox 250, Wyeth Pharmaceutical Ltd., India) failed to control symptoms and IOP (44 mmHg) in the left eye; she subsequently also developed corneal edema as compliance was questionable.

Thus, surgical intervention in the form of phacoemulsification (phaco) with implant, posterior chamber IOL (PCIOL), and endocycloplasty (ECPL) was undertaken in the left eye, 3 weeks after presentation.

Routine clear corneal superior phaco was done in the left eye, and PCIOL was inserted in the bag. Following this, cohesive viscosurgical device hyaluronic acid 1.2% (Aurogel, Aurolabs, India) was injected into the sulcus, under the iris, creating space for the endoscope. A 20-gauge curved endoscopic probe (Endo Optiks, Little Silver, NJ, USA), coupled with an 810 nm diode laser (IRIS Oculight SLx, Iris Medical Inc., Mountain View, CA, USA), was introduced into the eye through the clear corneal phaco wound, advanced posterior to the pupil and into the sulcus, and the ciliary processes and the cyst were visualized [Figure 2]. The endoscopic appearance of the ring cyst was ragged, with multiple out pouching, which was not evident on UBM. As a deviation from direct application of photocoagulation to the body of ciliary processes, ECPL was done as has been recently described for treatment of plateau iris syndrome.[6] In ECPL, typically, the tail of the ciliary processes [Figure 3] are targeted with the laser, to shrink them posteriorly, away from the iris.

Figure 2

Endoscopic appearance of ring iridociliary cyst in the left eye

Figure 3

Endocycloplasty before – laser beam (arrow) targeting tail of ciliary process. Endocycloplasty after – whitening and shrinking of ciliary process away from the cyst (arrow)

Approximately 210° were treated with 40 burns; power ranged between 250 and 500 mW, delivered at 1000–2000 ms setting. Individual ciliary processes were targeted, and endpoint of the laser treatment was determined by adequate whitening and shrinkage of the tail of the ciliary process, away from the cyst [Figure 3], avoiding iatrogenic rupture of the cyst. Following the procedure, viscoelastic was washed and wound checked for water tightness.

Postoperative day 1, patient had BCVA of 20/60 in the left eye and IOP of 10 mmHg with mild fibrinous reaction, which settled on application of topical steroids prednisolone 1% (Pred Forte, Allergan, Irvine, CA, USA) in a tapering dose over 6-weeks; she was also on a topical quinolone antibiotic (Vigamox, Allergan, Irvine, CA, USA) and cycloplegic homatropine hydrobromide 2% (Homide, Warren Excel and Warren Vision, Indoco Remedies, India) for 1 week. A visual field on Humphrey Field Analyzer (Carl Zeiss Meditec, Dublin, CA, USA) at 1 month postoperative was extremely unreliable. It however revealed constriction of visual field, correlating with extensive diffuse RNFL loss, as seen clinically in the left eye; it was within normal limits in the right eye.

Fellow right eye also underwent routine phaco with PCIOL, 3 months after presentation, with full visual recovery.

UBM was repeated at 3 months postoperative [Figure 4] and it revealed remnant of the cyst at 6 o'clock only; PCIOL was seen in situ together with synechial angle closure.

Figure 4

Remnant of ring cyst in the right eye at 3-months post surgery, in the presence of synechial angle closure

One year postoperatively, her BCVA was 20/20 in the right eye and 20/25 in the left eye; IOP was 15 and 12 mmHg, without any AGM, in the right and left eye, respectively. Gonioscopy continued to reveal 360° open angle in the right eye; 360° synechial angle closure was seen in the left eye. Disc appearance was unchanged and humphrey visual field (HVF) continued to be unreliable.

Discussion

Iridociliary cysts of pigment epithelium are rare, ring cysts being rarer still, and usually benign in their clinical course. Lois et al.[1] found these peripheral cysts to have greater female predilection when compared to the central pupillary cysts and in a series of 124 patients followed up for a mean of 35 months, only two cases developed glaucoma.

Though rare, these ring cysts are capable of causing secondary angle closure and glaucoma by its sheer bulk presence in the posterior chamber, pushing the iris anteriorly, promoting iridotrabecular contact and adhesion.

Management options that have been reported include laser iridocystotomy, both argon[3] and neodymium-doped yttrium aluminium garnet (YAG) laser assisted,[5] to rupture and cause collapse of the cyst; argon laser peripheral iridoplasty[7] has been described to counter the pseudo-plateau iris configuration.

Bron et al.[3] reported appositional angle closure due to ring cyst, visible at the slit lamp, that resolved on argon laser rupture of the cyst (pigment epithelial iridotomy) while transscleral diode photocoagulation (TSCPC) was used by Choudhari et al.[4] in synechial angle closure which failed to control IOP; incidentally, latter also reported resolution in appositional angle closure due to ring cyst with YAG iridotomy alone, in fellow eye. Kuchenbecker et al.[5] achieved re-opening of angle with the use of laser iridocystotomy, both argon and YAG laser, in a case of bilateral acute appositional angle closure with raised IOP secondary to iris cysts.

Rupture of the cyst can be fraught with complications, and severe protracted inflammation has been encountered in the past, when accidental rupture of cyst has occurred, following TSCPC.[4]

In our case, as there was no pupillary block, YAG laser peripheral iridotomy was not considered. In addition, in view of 360° synechial angle closure, collapse of cyst (cystotomy) too was not considered an option as control of IOP could potentially become a serious issue, in addition to possible inflammation, as encountered by Choudhari et al.[4] In our patient, direct visualization and ECPL achieved dual purpose – it helped us avoid rupture of cyst, potentially avoiding severe inflammation, and reduced aqueous production as evidenced by adequately controlled-IOP without medication; cataract extraction helped in visual rehabilitation.

The cyst was only partial in the right eye and had not resulted in any angle closure or raised IOP; this eye was visually rehabilitated with cataract surgery alone.

Conclusions

This case report highlights a novel technique (phaco-ECPL) in the successful management of ring iridociliary cyst when synechial angle closure occurs as iridotrabecular adhesion can present a challenge to the long-term control of IOP.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.