Urrets-Zavalia syndrome and secondary acute-angle closure glaucoma induced by implantable collamer lens

Abstract

Implantable collamer lenses (ICL) have revolutionized the management of high refractive errors, yet they present unique challenges. We present a case of a fixed and dilated atonic pupil following acute-angle closure glaucoma from pupillary block after ICL implantation, known as Urrets-Zavalia syndrome. A 39-year-old woman developed acute ocular pain and headaches after surgery, leading to elevated intraocular pressure and subsequent complications necessitating ICL removal. This case highlights the need for prompt identification and management of elevated intraocular pressure to prevent irreversible complications such as Urrets-Zavalia syndrome following ICL implantation.

KEY POINTS

• Implantable collamer lenses (ICLs) are used to treat high refractive errors.

• Elevated intraocular pressure and secondary glaucoma are known complications after ICL implantation, with acute glaucoma often caused by pupillary block.

• Design modifications, such as adding a central hole to ICLs, or prophylactic measures such as laser peripheral iridotomy, aim to reduce the risk of angle closure, though some cases still occur.

• This unique case highlights the need for prompt management of elevated postoperative intraocular pressure to prevent Urrets-Zavalia syndrome and associated complications.

CME

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CASE SUMMARY

A 39-year-old woman with high myopia (-10.00 sphere in both eyes) and normal preoperative intraocular pressure (IOP), pupil responsiveness, and corneal angle depth developed anisocoria and loss of vision after undergoing implantation of a nonholed ICL in the left eye (OS). Her past medical history was significant for migraines without aura treated with rizatriptan. The remainder of her surgical, family, social, and medical histories were noncontributory.

Two hours following ICL surgery, she developed acute, intractable ocular pain and headaches. The IOP was found to be 35 mm Hg, and she was immediately started on topical eyedrops of brimonidine tartrate 0.2%, timolol maleate 0.5%, prednisolone acetate 1%, and moxifloxacin 0.5%. She then developed worsening pain, nausea, and vomiting and returned to the outside ophthalmologist’s office 9 hours later. An anterior chamber paracentesis through the prior ICL corneal incision did not resolve the pain or loss of vision OS. A laser peripheral iridotomy was attempted but was unsuccessful due to poor visualization caused by corneal edema OS. A retina specialist on the same day noted 270° of angle closure OS via gonioscopy, but a normal angle in the right eye (OD). There was no view of the posterior segment, but an ocular ultrasound B-scan did not show retinal detachment or endophthalmitis. The next day, her ICL OS was explanted and the corneal edema improved, but her vision remained unchanged. Additional diagnostic studies such as cranial computed tomography, contrast computed tomography angiography, carotid Doppler, and transthoracic echocardiogram were all unremarkable. A hypercoagulable state evaluation showed homozygosity for the methylene tetrahydrofolate reductase (MTHFR) mutation.

On initial neuro-ophthalmology examination 1 month after the surgery, her visual acuity was 20/70 in the OD and counting fingers OS. The pupil OS measured 8 mm and was nonreactive to light or near stimuli. The pupil OD showed tonic near reaction with vermiform movement (Figure 1) suggestive of a tonic pupil OD. No relative afferent pupillary defect was noted. Humphrey visual field testing (24-2) showed a mean deviation of −3.37 decibels (dB) OD and −19.94 OS (Figure 2). Pilocarpine 1% hydrochloric acid drops OS did not constrict the pupil, consistent with a postoperative, atonic Urrets-Zavalia syndrome.

Figure 1.

External colored photograph showing a fixed and dilated left pupil.

Figure 2.

Humphrey visual field showing (a) visual field damage of the left eye, along with (b) total deviation and (c) pattern deviation.

CLINICAL QUESTIONS

1. A 30-year-old man with manifest refractive spherical equivalent of -11 D presents to the clinic desiring refractive correction surgery and is found to be a poor candidate for LASIK. The patient opts to move forward with ICL placement after a discussion of the risks and benefits, including possible infection, cataract development, and glaucoma. What is a primary cause of acute glaucoma after ICL implantation? How have design modifications of ICLs addressed this issue?

   1. Increased production of aqueous; sustained released latanoprost within ICLs.

   2. Pupillary block due to ICL obstructing aqueous flow; introduction of central holes to ICL.

   3. Preexisting narrow iridocorneal angles; concurrent iridotomy with ICL placement.

   4. Acute glaucoma is not a risk of ICL placement; no changes have been made.

2. A 32-year-old woman who is 1 day status post nonholed IC placement presents to the emergency room with uniocular decreased vision, pain, headache, and an IOP of 45. Acute glaucoma is suspected. How long can postoperative glaucoma be delayed after ICL implantation?

   1. It will happen immediately following surgery.

   2. It will happen within the first postoperative month.

   3. It will happen within the first postoperative year.

   4. It can happen many years after surgery.

Answers are provided at the end of the article.

DISCUSSION

ICLs are a specialized type of posterior chamber phakic intraocular lenses used to treat high refractive errors.^1,2 ICLs are made of specialized collagen copolymers and are surgically implanted inside the eye, between the iris and the natural lens.¹ Although first implanted in 1993, since their approval in 2005, ICLs have undergone many design modifications.^3–5 Complications of ICL placement include pupillary block, intraocular inflammation, cataract formation, and increased IOP.^6,7 Elevated IOP and secondary glaucoma account for up to 4.4% of complications after ICL implantation.¹ Postoperative glaucoma can be acute or chronic and can be delayed up to 5 to 8 years after surgery.^1,2

One cause of acute glaucoma after ICL implantation is pupillary block.² The lens can block the flow of aqueous from the posterior chamber to the anterior chamber, elevating IOP. Design modifications for holed and nonholed ICLs have been proposed to try to mitigate the risk for angle closure after ICL. While most cases of pupillary block previously occurred after placement of an ICL without a central hole, some cases have occurred despite a central hole. This may be due to the abnormal aqueous flow and misdirection without the central pore.^3–5 More cases occur without a hole because of the decreased ability for aqueous flow around the implantable lens, while the hole allows for improved mobility of aqueous. In these cases of nonholed ICLs, preoperative laser peripheral iridotomy and assured patency are important for good aqueous humor flow.^6,7 ICLs containing a central hole that developed pupillary block and angle closure glaucoma presumably developed central hole obstruction by viscoelastic retention, iris, iris pigment, or inflammatory debris (Table 1).^3,4,8–15

Table 1.

Case reports of patients with ICL implantation who presented with pupillary block

Reference	Case description	Reported IOP	Pupillary description
Frost et al, 20198	29-year old female with previous ICL implantation	44 mm Hg at time of presentation 5 years after ICL implantation	Pupil was mid-dilated and fixed at 6 mm
Gonzalez-Lopez et al, 20199	28-year-old female with recent central-holed ICL implantation	42 mm Hg on first postoperative day	Pupil was centered, rounded, in mild mydriasis, and slightly reactive to light
Mansoori et al, 201910	20-year-old male with previous central-holed ICL implantation and recent vitreoretinal surgery	44 mm Hg 2 years after ICL implantation and 2 weeks after retinal detachment surgery	Pupil was 3 to 4 mm dilated in the left eye and sluggishly reacting to the light
Grover et al, 201711	28-year-old female with recent central-holed ICL implantation	60 mm Hg on first postoperative day	Pupil was fixed and dilated
Mimouni et al, 202012	32-year-old female with recent central-holed ICL implantation and toxic anterior segment syndrome	44 mm Hg on seventh postoperative day	Pupil was fixed and mid-dilated
Al Habash et al, 201513	28-year-old female with recent ICL implantation	Unavailable	Pupil was fixed and mid-dilated
Al-Thomali et al, 201614	32-year-old female with recent ICL implantation	28 mm Hg several hours after surgery	Pupil was mid-dilated
Niruthisard et al, 202115	20-year-old male with recent central-holed ICL implantation	48 mm Hg	Pupil was 6 mm and slightly reactive to light

In summary, this case of a 39-year-old woman who developed fixed and dilated atonic pupil ICL implantation is a unique example of Urrets-Zavalia syndrome. It illustrates the importance of prompt identification and management of elevated postoperative IOP to prevent Urrets-Zavalia syndrome and associated complications.

ANSWERS TO CLINICAL QUESTIONS

Question 1, b. Pupil block is a primary cause of acute angle closure glaucoma, including in patients who are post-ICL placement. ICLs have now been developed with central holes that allow for better aqueous flow, so it is important that these holes remain patent from viscoelastic or other debris. While the risk of pupil block is lower with this design, cases have still been described.

Question 2, d. While cases of acute glaucoma after ICL surgery can occur very soon postoperatively, several cases have been described years after the surgery.

Disclosure statement/Funding

The planners and faculty for this activity have no relevant financial relationships to disclose. The authors report no funding. The patient consented to publication of this case report.