Pars plana vitrectomy for malignant glaucoma in nonglaucomatous and in filtered glaucomatous eyes

Successful Pars Plana Vitrectomy with Zonulo-hyaloidectomy Performed 4 Years after the Onset of Chronic Low-Grade Aqueous Misdirection

In aqueous misdirection, the interval between diagnosis and surgical intervention is inversely proportional to the success of the surgery. Here, we report a successful outcome of pars plana vitrectomy (PPV) with irido-zonulo-hyaloidectomy 4 years after the onset of the disease. A 34-year-old female, known to have primary angle closure glaucoma, underwent trabeculectomy with mitomycin C in the right eye for uncontrolled intraocular pressure (IOP). Six weeks after the surgery, the patient presented with a shallow anterior chamber centrally and peripheral iridocorneal touch along with a patent peripheral iridectomy. Ultrasound biomicroscopy showed a shallow AC centrally with peripheral iridocorneal touch, and the ciliary body was rotated forward confirming the diagnosis of aqueous misdirection. The patient refused surgical management and was managed medically, which was unsuccessful. Four years after the diagnosis, the patient underwent PPV with irido-zonulo-hyaloidectomy because of progressive shallowing of the AC and corneal edema. One month postoperatively, visual acuity improved from 20/200 to 20/60, and the AC maintained appropriate depth. In conclusion, PPV with irido-zonulo-hyaloidectomy may result in a complete resolution of a chronic low-grade form of aqueous misdirection.

Factors Impacting Outcomes and the Time to Recovery From Malignant Glaucoma

PURPOSE

To identify factors associated with the successful treatment of malignant glaucoma (MG).

DESIGN

Retrospective case series.

METHODS

Setting: single institution; study population: 64 eyes (55 subjects) with MG; observation procedure(s): chart review; main outcome measures: anatomy, intraocular pressure (IOP), best visual acuity (BVA).

RESULTS

87.5% (n=56/64) of eyes with MG required surgical intervention. Vitrectomy was more likely to be successful in eyes with a history of <3 incisional surgeries, <3 glaucoma drops, or IOP ≤30 mm Hg (P < .05). If vitrectomy was performed within 30 days, recovery of anatomy, BVA, and IOP occurred sooner (P < .05). IOP reduction was greater in subjects treated with oral carbonic anhydrase inhibitors (P = .016) or Nd:YAG laser hyaloidotomy (P = .007), and without a history of MG (P = .007). Time to maximal improvement was significantly longer for IOP and BVA than anatomy (P < .001). Treatment of MG with an oral carbonic anhydrase inhibitor hastened anatomic recovery (P = .01). Time to improvement in BVA was significantly faster in men and African Americans (P < .05). Time to maximal reduction in IOP occurred sooner in eyes that underwent anterior chamber reformation in clinic (P < .002). Trabeculectomy surgery prior to MG was associated with prolonged recovery of anatomy, BVA, and IOP (P < .05).

CONCLUSIONS

Earlier vitrectomy may shorten recovery times for MG. Nd:YAG laser hyaloidotomy and oral carbonic anhydrase inhibitors may lead to greater IOP reduction. The time to maximal improvement in IOP and BVA may be longer than the time to anatomic resolution. Although trabeculectomy may impede time to recovery from MG, oral carbonic anhydrase inhibitors may shorten the time to anatomic recovery and anterior chamber reformation may hasten IOP recovery.

Spontaneous malignant glaucoma: Case report and review of the literature

Malignant glaucoma usually occurs after anterior segment surgery (typically after glaucoma surgery). The aim of this article is to report a case of spontaneous malignant glaucoma (SpMG), which required phacovitrectomy for resolution and to review the cases of SpMG reported in modern literature. Only nine cases were identified. SpMG has no gender predilection and age at onset seems to be lower (mean age 47 years) than in secondary malignant glaucoma (SeMG). Nearly in half of the reported patients (4 out of 9) the condition had a bilateral presentation. The risk factors that have been identified for SeMG (nanophthalmos, shallow anterior chamber, iris plateau, zonular laxity) are underrepresented in SpMG.

Prophylactic anterior vitrectomy during cataract surgery in eyes at increased risk for aqueous misdirection

PURPOSE

Patients with chronic narrow angle glaucoma (CNAG) are at increased risk of developing aqueous misdirection (AM) following intraocular surgery. We present a retrospective case series on the use of posterior capsulorrhexis with core vitrectomy by an anterior approach (CAV) at the time of cataract extraction with or without glaucoma surgery as a prophylactic measure for the prevention of AM in CNAG.

METHODS

Retrospective case series of six phakic eyes in four patients with CNAG and other risk factors for AM who underwent posterior capsulorrhexis and CAV at the time of cataract surgery with or without glaucoma surgery. The main outcome measures were best-corrected visual acuity (BCVA), intraocular pressure (IOP), and post-operative complications.

RESULTS

Six eyes in four subjects underwent posterior capsulorrhexis with CAV at the time of cataract surgery. The case was combined with incisional glaucoma surgery in the five eyes with advanced visual field loss. The mean logMAR BCVA and IOP improved from 0.554 ± 0.398 and 25.2 ± 13 mmHg, respectively, at the pre-operative visit to 0.257 ± 0.218 and 12.2 ± 1.7 mmHg, respectively, at final follow-up. Both eyes with nanophthalmos developed non-appositional serous choroidals that resolved with atropine, but the left eye required additional treatment with synechiolysis, intraocular lens repositioning, limited AV and endocyclophotocoagulation. There were no permanent, vision-threatening complications.

CONCLUSIONS AND IMPORTANCE

CAV can be safely combined with cataract surgery and glaucoma surgery, and it may be an effective intervention in eyes with CNAG and other risk factors for AM as a prophylactic measure against the development of AM.

Acute and chronic fluid misdirection syndrome: pathophysiology and treatment

Purpose

To summarize our current understanding of the specific pathogenic mechanisms of the fluid misdirection syndrome and possible treatment methods.

Methods

We used the PubMed web platform to find relevant studies using the following keywords: infusion misdirection syndrome, aqueous misdirection syndrome, ciliary block, ciliovitreal block, capsular block, intraoperative fluid misdirection, subcapsular fluid entrapment, acute intraoperative rock-hard eye syndrome, positive vitreous pressure glaucoma, and malignant glaucoma. Other publications were also considered as a potential source of information when referenced in relevant articles.

Results

We collected and analyzed 55 articles dated from 1951 to 2016. Acute intraoperative rock-hard eye syndrome is characterized by a very shallow anterior chamber with the absence of suprachoroidal effusion or hemorrhage and no noticeable pathology of the iris–lens diaphragm. It usually occurs during uneventful phacoemulsification, particularly in hyperopic eyes. The pathophysiology of acute fluid misdirection syndrome is based on inappropriate movement of balanced salt solution via the zonular fibers. This syndrome has also been described as occurring from hours to months, or years, after the initial surgery. The pathophysiology of malignant glaucoma is based on similar mechanisms of cilio-lenticular block of aqueous flow leading to the misdirection of aqueous posteriorly into or besides the vitreous gel. Faced with these situations, vitreous decompression is required, preferably with hyaloido-capsulo-iridectomy. In phakic eyes, concomitant cataract extraction would be desirable.

Conclusions

We believe both of these clinical conditions should be considered as one syndrome. We suggest the term acute fluid misdirection syndrome for the cascade of events during phacoemulsification surgery. Chronic fluid misdirection syndrome better describes the nature of malignant glaucoma.

Current concepts in the treatment of vitreous block, also known as aqueous misdirection

Vitreous block (VB), a rare secondary angle-closure caused by anterior rotation of the ciliary body, occurs in a variety of settings, but most frequently after glaucoma filtering surgery. The etiology remains unclear, but choroidal expansion and anterior vitreous abnormalities have been proposed. In the past, treatment of VB has yielded high rates of failure and recurrence. Advancements in surgical techniques, however, have led to improved visual outcomes. We review the history of this condition and present a stepwise approach to its diagnosis and treatment using modern imaging modalities and surgical techniques.