Malignant glaucoma with variable outcomes after irido-zonulo-hyaloid-vitrectomy-bilateral involvement: a case report

Abstract

Introduction

Malignant glaucoma is an uncommon but serious complication of intraocular surgery, including filtration surgery and phacoemulsification, with an incidence of 2–4%. It arises from an obstruction in aqueous humor flow, leading to elevated posterior pressure and subsequent complications. Delayed or insufficient treatment can result in irreversible vision loss. This case highlights the importance of early surgical intervention and anti-inflammatory management for preventing complications and achieving improved outcomes.

Case presentation

A 56-year-old Chinese woman presented with bilateral malignant glaucoma. The initial treatment of the right eye involved medications for 3 months, followed by yttrium aluminium garnet laser posterior capsulotomy, which offered limited success. Irido-zonulo-hyaloid-vitrectomy was eventually performed, successfully normalizing her intraocular pressure but resulting in macular cystoid edema 6 months later. Her left eye, diagnosed with malignant glaucoma 2 months after the right eye’s presentation, received early intervention with cataract extraction, intraocular lens implantation, and irido-zonulo-hyaloid-vitrectomy. This approach yielded excellent outcomes, with optimal intraocular pressure control and preserved vision without complications.

Conclusion

This case underscores the importance of early surgical intervention, particularly irido-zonulo-hyaloid-vitrectomy, in managing malignant glaucoma. Early intervention can prevent postoperative complications such as macular edema and ensure superior visual outcomes. Tailored anti-inflammatory approaches further mitigate associated risks and enhance long-term prognosis in cases of bilateral involvement.

Introduction

Malignant glaucoma is a rare but serious complication of intraocular surgery. While classically associated with filtration surgery for angle-closure glaucoma, it can also occur following cataract extraction (phacoemulsification) or laser procedures, with an estimated incidence of approximately 2–4% [1]. This condition is caused by an obstruction in aqueous humor circulation, leading to a posterior shift in pressure and anterior displacement of the lens-iris diaphragm [2]. Commonly used treatments include topical medications, laser therapy, and surgery [3, 4]. However, delayed or inadequate treatment can result in severe vision loss.

There is a lack of literature directly comparing the outcomes of early versus delayed surgical intervention with irido-zonulo-hyaloid-vitrectomy (IZHV) in the same patient with bilateral involvement. This case is unique as it provides a rare, direct comparison of these two management strategies. It highlights the critical impact of treatment timing on postoperative complications, such as macular edema, and underscores the significance of early surgical intervention and tailored anti-inflammatory strategies for improved prognosis.

Case presentation

A 56-year-old Chinese woman presented with blurred vision and ocular discomfort in her right eye following cataract surgery (phacoemulsification with intraocular lens implantation) for acute angle-closure glaucoma performed at an external facility. No filtration procedure (trabeculectomy) was combined with the primary cataract surgery. She received initial treatment with timolol, brimonidine, and brinzolamide eye drops for 3 months, but her symptoms persisted.

Examination findings and management of right eye (OD)

Upon presentation to our clinic, the examination revealed:

• Visual acuity: best-corrected visual acuity (BCVA) was 20/160.

• Anterior segment: anterior chamber depth (ACD) was extremely shallow at 1.56 mm; intraocular pressure (IOP) was 28 mmHg. Slit-lamp examination showed conjunctival congestion (++) and iris depigmentation with pigment deposits on the intraocular lens.

• Gonioscopy: gonioscopy revealed extensive peripheral anterior synechiae (PAS) with 360-degree angle closure, despite the presence of a patent pseudophakic status.

• Posterior segment imaging: B-scan ultrasonography was performed to rule out suprachoroidal hemorrhage or effusion; no fluid pockets in the vitreous space or supraciliary choroidal effusions were observed.

Clinical course

Initial conservative management was attempted. After 1 week of intensive medical therapy failing to deepen the anterior chamber, a yttrium aluminium garnet (YAG) laser posterior capsulotomy was performed to disrupt the anterior hyaloid face. However, the anterior chamber remained shallow, and the IOP remained uncontrolled. Consequently, IZHV was performed in the right eye. Postoperatively, BCVA was restored to 20/32, ACD increased to 2.68 mm, and IOP normalized between 15 and 16 mmHg.

Contralateral eye (left eye) management

At 2 months after the presentation of the right eye, the patient complained of pain and blurred vision in the left eye.

• Examination: the left eye (OS) developed elevated IOP (35 mmHg) and a shallow anterior chamber (depth 1.16 mm) (Fig. 1). Gonioscopy confirmed angle closure. Although the patient had a diagnosis of primary angle-closure suspect in the left eye, the progression was rapid, and the attack occurred before prophylactic laser peripheral iridotomy (LPI) had been performed.

• Diagnosis and intervention: a diagnosis of primary malignant glaucoma was made. Unlike the delayed approach in the right eye, early intervention was initiated. The patient underwent phacoemulsification, intraocular lens implantation, and concurrent IZHV.

• Outcome: this early surgical approach achieved excellent outcomes, including a BCVA of 20/20 and stable IOP between 18 and 20 mmHg.

Fig. 1.

Bilateral anterior segment photography and Pentacam analysis. After irido-zonulo-hyaloid-vitrectomy surgery, the anterior chamber depth of the right eye measures 2.53 mm, and the pupil diameter is 3.16 mm (a, b). In contrast, the pupil diameter of the left eye is 1.91 mm, the direct light reflex is absent, and the anterior chamber depth is 1.16 mm. Pantacam analysis indicates that the peripheral iris is in contact with the corneal endothelium (c, d)

Follow-up and complications

Complications arose 6 months post-IZHV in the right eye, with macular cystoid edema documented by optical coherence tomography (OCT) (Fig. 2a). Other etiologies of cystoid macular edema (CME), including diabetic retinopathy, retinal vein occlusion, and uveitis, were ruled out through clinical examination and history taking. Repeated triamcinolone injections provided transient improvement, but recurrent edema persisted (Fig. 2b–f). The left eye, which underwent early IZHV, remained complication-free throughout the follow-up period.

Fig. 2.

Changes in macular edema after right eye surgery; 6 months after the right eye irido-zonulo-hyaloid-vitrectomy surgery, cystoid macular edema developed in the macular region, characterized by several cystic structures in the retinal nerve epithelium layer and visible fluid dark areas. During this period, three injections of 20 mg methylprednisolone acetate were administered around the right eyeball, but no reduction in macular edema was observed (a). In the seventh month post surgery, an intravitreal injection of 2 mg triamcinolone acetonide was administered. A follow-up optical coherence tomography 1 week later revealed a significant decrease in macular thickness compared with the pre-injection state (b). By the ninth month post surgery, a follow-up optical coherence tomography showed that macular edema had recurred, with an increase in the elevation height compared with previous observations (c). In the tenth month post surgery, another intravitreal injection of 2 mg triamcinolone acetonide was given. A follow-up optical coherence tomography one week later revealed a significant decrease in macular thickness, with the macular morphology and structure returning to near-normal (d). By the fourteenth month post surgery, the macula was edematous again, with increased elevation height noted during a follow-up optical coherence tomography. After another intravitreal injection of 2 mg triamcinolone acetonide, the macular edema was alleviated (e). At the twenty-fourth month post surgery, a follow-up optical coherence tomography showed increased thickness in the nerve epithelium layer of the right macula, with scattered small fluid dark areas present. This indicated the persistence of macular edema in the right eye (f)

Discussion

This case underscores the variations in clinical outcomes based on treatment timing and protocol. Malignant glaucoma is characterized by anterior displacement of the lens-iris diaphragm, shallow anterior chamber, and disruption of aqueous humor circulation [5]. The pathophysiology in this case suggests overall anterior lens-iris diaphragm displacement as the primary mechanism. It is important to note that while malignant glaucoma is often associated with trabeculectomy, it can occur in pseudophakic eyes following routine phacoemulsification, particularly in eyes with a history of angle closure, as seen in this patient.

Surgical approach

IZHV remains the gold standard by establishing aqueous humor communication between anterior and posterior segments [6, 7]. In this patient, the left eye underwent combined phacoemulsification and IZHV immediately upon diagnosis, preventing the cycle of chronic inflammation.

Pathogenesis and complications

Macular cystoid edema is a known postoperative complication associated with inflammation [8]. Proinflammatory mediators likely disrupted the blood–retinal barrier, supported by the patient’s response to corticosteroid therapy. The development of cystoid macular edema (CME) in the right eye, but not the left, is a key finding of this case. The link is likely not with the IZHV procedure itself, but with the timing of the intervention. The right eye endured 3 months of persistent high IOP and associated subclinical inflammation before the YAG laser, with further delay before the definitive IZHV. This prolonged period of ocular hypertension and inflammation likely compromised the blood-retinal barrier. The subsequent (but necessary) surgical trauma of the IZHV, combined with this preexisting vulnerability, probably triggered the inflammatory cascade that led to persistent, recurrent CME [8].

Regarding the left eye, the absence of a patent peripheral iridotomy (PI) prior to the acute attack highlights the aggressive nature of the disease in this patient. Even in the absence of a prior filtration procedure, the anatomical predisposition led to a malignant mechanism. The prompt IZHV in the left eye resolved the pressure and inflammatory stimulus quickly, thereby preserving the integrity of the blood–retinal barrier and preventing CME. This strongly supports the hypothesis that the CME was a consequence of delayed management, rather than a direct complication of the IZHV procedure.

Conclusion

Here, we report a case of bilateral malignant glaucoma that underwent surgical treatment sequentially. The strategies for managing both eyes were different; although the right eye developed macular edema postoperatively, both eyes ultimately maintained normal anterior and posterior chamber pressures. By comparing different treatment plans, we emphasize the importance of early surgical intervention and active anti-inflammatory measures to prevent vision-threatening complications such as CME.

Author contributions

NL collected the samples and drafted the manuscript. YD and FL supervised and approved the study, revised the manuscript, prepared the figures, and provided the funds for this research.

Funding

This study was supported by the International Science and Technology Co-operation Program of Henan (grant no. 232102521033), and the Medical Education Research Project of Henan (grant no. WJLX2022165), and the Henan Province Medical Science and Technology Key Project (grant no. LHGJ20230956).

Availability of data and materials

The datasets used and/or analyzed during the current study are available from the corresponding author on reasonable request.

Declarations

Ethics approval and consent to participate

This study protocol was reviewed and approved by Sanmenxia Eye Hospital, approval no. 20240321.

Consent for publication

Written informed consent was obtained from the patient for publication of this case report and any accompanying images. A copy of the written consent is available for review by the Editor-in-Chief of this journal.

Competing interests

The authors have no conflicts of interest to declare.