Analytical model for managing hypotony after implantation surgery of a glaucoma drainage device.

The main aim of glaucoma treatment is to reduce the intraocular pressure (IOP). One of the most common surgical treatments of glaucoma is the implantation of a glaucoma drainage device to drain the aqueous humor from the anterior chamber to a filtration bleb, where the aqueous humor is absorbed. In some cases, the excess of drainage causes ocular hypotony, which constitutes a sight-threatening complication. To prevent hypotony after this intervention, surgeons frequently introduce a suture into the device tube, which increases the hydraulic resistance of the tube and, therefore, the IOP. This study aims to provide an analytical model to correct hypotony following implantation surgery of a glaucoma drainage device, which may help glaucoma surgeons decide on hypotony treatment. The results indicate that the IOP after implanting a cylindrical tube around 300 µm in diameter is essentially the same as that built up in the filtering bleb and can hardly be controlled by introducing a straight suture unless the suture diameter is slightly lower than that of the tube. On the contrary, when the tube diameter is smaller than, for example, 100 µm, significant reductions of the IOP can be obtained by introducing a thin suture into the tube.

Pembrolizumab-related Bilateral Ocular Hypotony, Uveitis, Cataracts, Exudative Retinal, and Choroidal Detachments: An Unusual Success Story.

Here, we report the presentation and management of a rare case of sight-threatening bilateral panuveitis with secondary chronic hypotony, subcapsular cataracts, exudative retinal detachments, and choroidal detachments, following initiation of pembrolizumab immunotherapy for metastatic melanoma. An 82-year-old white woman presented with painful, blurry vision 3 days after initiation of pembrolizumab immunotherapy. She had developed a marked panuveitis causing secondary hypotony. The fundal view was entirely limited by acutely dense cataracts and small, uveitic pupils unresponsive to topical dilation. Urgent cataract surgery with intravitreal dexamethasone implant (Ozurdex) was completed successfully and allowed a fundal examination. This revealed bilateral, symmetrical, inferior exudative retinal detachments, and choroidal detachments secondary to chronic hypotony. After 3 months of observation and cessation of oral steroids, the panuveitis remains quiescent, hypotony persists, and the choroidal and retinal detachments are showing progressive self-resolution. The current best-corrected visual acuity is 6/24 OU. She remains under close monitoring. The immune checkpoint inhibitor, pembrolizumab, has been reported to cause sight-threatening adverse effects. We report a rare case of profound bilateral complications treated successfully with oral and intravitreal steroids. To the authors' knowledge, this has not previously been reported in the literature. Ophthalmologists and oncologists should be aware of the ocular effects of pembrolizumab and be able to identify various complications early. Here, cataract surgery with a steroid implant has been an effective sight-saving intervention. The promising visual outcome makes this an unusual success story.

[Cyclodialysis, a therapeutic challenge: Review of the literature on current practices]. / Cyclodialyse : un challenge thérapeutique, revue de la littérature sur les pratiques actuelles.

INTRODUCTION: Cyclodialysis is a rare condition that is difficult to manage. We present the case of a woman with a cyclodialysis complicated by chronic hypotony requiring two surgeries to achieve reattachment of the ciliary body. We also report the results of a review of the literature regarding the treatment of this condition. DESCRIPTION: This is a 46-year-old woman with history of trauma to the right eye. Examination revealed an intra-ocular pressure (IOP) of 7mmHg, a shallow anterior chamber and signs of chronic hypotony on fundus examination (vascular tortuosity, hypotony maculopathy) due to an extensive 360° cyclodialysis, confirmed by ultrasound biomicroscopy. Transcleral cryotherapy as a first-line approach did not achieve reattachment of the ciliary body. Secondary pars plana vitrectomy with gas tamponade (C2F6) reattached the ciliary body and restored the intraocular pressure (12mmHg) and normal fundus appearance. The patient recovered corrected visual acuity of 20/20. DISCUSSION: To our knowledge, there is no standardized management for cyclodialysis. The study of the literature available on the Medline database showed that direct cyclopexy remains the most common treatment, followed by vitrectomy with internal tamponade. Neither the extent nor the duration of the cyclodialysis can predict the visual recovery, which can be major even after weeks of hypotony. CONCLUSION: The management of cyclodialysis is not well-defined; it remains a true therapeutic challenge.

Treatment of chronic and extreme ocular hypotension following glaucoma surgery with intraocular platelet-rich plasma: A case report.

PURPOSE: To report a new approach for the treatment of severe ocular hypotony secondary to glaucoma filtering surgery with mitomycin C by injecting autologous eye platelet-rich plasma (E-PRP) in the anterior chamber to block excessive diffuse filtration through an abnormally thinned sclera. METHODS: A 49-year-old patient with the Axenfeld-Rieger syndrome and severe chronic hypotony and corneal edema following filtering glaucoma surgery with mitomycin C received an isolated injection of 0.3 mL of autologous platelet-rich plasma in the anterior chamber. RESULTS: Intraocular pressure measured by Goldman's applanation tonometry 6 h after the procedure improved to 18 mmHg. Intraocular pressure remained stable along the full follow-up period of 6 month. No filtration or hypotony or any other complications were observed. CONCLUSION: Intracameral platelet-rich plasma (E-PRP) injection was an effective, rapidly effective, and safe procedure for treatment of severe chronic ocular hypotony following glaucoma filtrating surgery.

The treatment of ocular hypotony after trabeculectomy with a scleral lens: A case series.

PURPOSE: Ocular hypotony after trabeculectomy may be treated medically, surgically and with a tamponade. Three cases are reported in which a scleral lens was applied to treat ocular hypotony after mitomycin C (MMC) augmented trabeculectomy. METHODS: In this retrospective case series the records of three eyes of three patients who developed ocular hypotony after they had undergone trabeculectomy augmented with MMC were evaluated. The patients were between 11 and 69 years of age and the intraocular pressure (IOP) after surgery ranged between 3 and 6 mmHg. All three patients showed a negative Seidel test; one had suspected hypotonic maculopathy and one had a collapsed anterior chamber. After unsuccessful treatment with large bandage lenses all three patients were subsequently fitted with a scleral lens. The scleral lens was fitted to fully cover and compress the bleb. Scleral lenses were worn continuously with a check-up after one night of wear and subsequent check-ups when needed. One patient continued to wear the scleral lens for a further 6.5 months on a daily wear basis. RESULTS: In all three eyes the IOP was higher after wearing the scleral lens. Two patients stopped wearing the scleral lens after the IOP was stable. One patient developed a cataract; the cataract surgery was combined with a bleb revision and scleral lens wear was therefore discontinued. DISCUSSION: The scleral lens might be a useful tool in the treatment of ocular hypotony after trabeculectomy augmented MMC surgery. The effect of the scleral lens on the ocular pressure is unpredictable. Caution is advised in vulnerable corneas due to risk factors such as hypoxia and infection. Further research is warranted to establish the safety of the procedure, the patient selection and the overall success in a larger patient group.

Suturas transconjuntivales del tapete escleral en maculopatía hipotónica tardía tras esclerectomía profunda no perforante / Transconjunctival suturing of the scleral flap in late hypotony maculopathy after non-penetrating deep sclerectomy

CASO CLÍNICO: Un hombre de 63 años desarrolla una maculopatía hipotónica tardía tras una esclerectomía profunda no perforante. La sutura transconjuntival del tapete escleral permite resolver la hipotonía y la normalización de la agudeza visual. DISCUSIÓN: La maculopatía hipotónica puede presentarse de forma diferida tras una cirugía de glaucoma. Las suturas transconjuntivales del tapete escleral son una alternativa en el tratamiento de la hipotonía cuando las medidas conservadoras han fracasado

CLINICAL CASE: A 63-year-old man presents with late hypotony maculopathy after non-penetrating deep sclerectomy. Hypotonia and visual acuity are improved after transconjunctival suturing of the scleral flap. DISCUSSION: Hypotony maculopathy may occur as a late complication after glaucoma surgery. Transconjunctival suturing of the scleral flap can be useful when conservative measures have failed

Maculopatia hipotônica pós ciclodiálise traumática por arma de fogo / Hypotonic maculopathy post traumatic cyclodialysis with firearms

Resumo Um traumatismo ocular contuso pode gerar uma vasta gama de lesões intraoculares que são dependentes da quantidade de energia que o objeto transfere ao olho durante o impacto. As lesões da íris, malha trabecular e corpo ciliar podem repercutir na drenagem do humor aquoso. A ocorrência de uma ciclodiálise caracterizada pelo descolamento do corpo ciliar da parede escleral, criando uma comunicação entre a câmara anterior e o espaço supracoroidiano, pode provocar importante redução da pressão intraocular. Esta diminuição pressórica é a responsável pela ocorrência da maculopatia hipotônica que pode cursar com diminuição irreversível da acuidade visual. Não existe consenso na literatura sobre o tratamento das ciclodiálises. Neste relato, descrevemos um caso de ciclodiálise traumática pós impacto com projétil de arma de fogo tratada com aplicação de laser de argônio.

Abstract Blunt eye trauma can generate a wide range of intraocular lesions that are dependent on the amount of energy the object transfers to the eye during the impact. Lesions of the iris, trabecular meshwork and ciliary body may influence aqueous humor drainage. The cyclodialysis which is characterized by the detachment of ciliary body from the scleral wall, creating a communication between the anterior chamber to supracoroid space, can cause a several reduction of intraocular pressure. This pressure decrease is responsible for the occurrence of hypotonic maculopathy which may induce a severe impact on visual acuity. There is no consensus in the literature about cyclodialysis treatment. In this report, we describe a case of traumatic cyclodialysis after impact with a firearm projectile treated with argon laser photocoagulation.

Anterior Chamber Sulfur Hexafluoride (SF6) Injection for the Management of Postsurgery Hypotony in Glaucoma Patients.

PURPOSE: The purpose of this article was to describe a new technique involving the injection of sulfur hexafluoride (SF6) gas in the anterior chamber (A/C) for the management of hypotony in patients with previous glaucoma surgery. MATERIALS AND METHODS: Seven patients were included in this prospective case series. All patients had advanced glaucoma that was managed surgically either by trabeculectomy (6 patients) or Ahmed valve (1 patient). All patients presented with intraocular pressure (IOP) <7 mm Ηg, shallow A/C, and ultrasound images of choroidal detachment and ciliary body detachment. Patients' hypotony was treated by 0.4 to 0.6 mL of 100% pure SF6 injection in the A/C followed by supine posture. The purpose of this injection was dual: to displace the ciliary body to its normal position and restore aqueous humor normal production, and to block aqueous humor outflow through bubble formation, causing an increase in IOP. RESULTS: Surgical technique was successful in all 7 patients with IOP normalization (>10 mm Hg) and A/C depth increase within the first week after surgery. CONCLUSION: A new surgical technique of SF6 injection in the A/C for patients with choroidal detachment and hypotony shows promising results.

[Ocular Hypotension: How the Retina Surgeon Sees the Causes and Therapeutic Options]. / Okuläre Hypotonie - Ursachen und therapeutische Möglichkeiten aus Sicht des Netzhautchirurgen.

Ocular hypotension is a result of a lack of production or a loss of intraocular fluid. Intraocular inflammation, drugs, or proliferative vitreoretinopathy (PVR) with overgrowth of the ciliary body can result in reduced secretion of intraocular fluid. Loss of intraocular fluid can result from external loss, such as in fistulating surgery or trauma, or internally, e.g. from cyclodialysis clefts or retinal detachment. In this review, we discuss the causal therapy of ocular hypotension: fixation of the ciliary body, removal of ciliary body membranes, surgery for PVR, choice of tamponade, possibilities and limitations of an iris diaphragm, and pharmacological options.

Pars plana vitrectomy, fluocinolone acetonide implantation, and silicone oil infusion for the treatment of chronic, refractory uveitic hypotony.

PURPOSE: To assess the feasibility and outcomes of combining fluocinolone acetonide sustained drug delivery implant insertion, pars plana vitrectomy, and silicone oil infusion to treat patients with chronic, refractory ocular hypotony resulting from uveitis. DESIGN: Retrospective chart review. METHODS: A retrospective, institutional chart review was performed. Outcome measures included visual acuity, intraocular pressure, and adverse events. RESULTS: A total of 13 eyes of 11 patients were studied. All patients were women, had a mean age of 57 years (range, 26 to 73 years), and had a diagnosis of panuveitis. The mean duration of preoperative hypotony was 42 months (range, 11 to 108 months). Patients were followed up on average for 22 months (range, 9 to 46 months) after the combined surgical procedure. The mean preoperative visual acuity was 20/1000 (logarithm of the minimal angle of resolution, 1.7). At the 6- and 12-month visits, the mean visual acuity remained stable at 20/800 (logarithm of the minimal angle of resolution, 1.6; P = .74) and 20/600 (P = .34), respectively. At baseline, the mean intraocular pressure (IOP) was 2.3 mm Hg. The average IOP was 5.9 mm Hg, 5.1 mm Hg, and 5.0 mm Hg at 6, 12, and 24 months after surgery, respectively. The increase in IOP relative to the baseline IOP was statistically significant at 6 and 12 months (P = .027 and P = .004, respectively). The duration of preoperative hypotony inversely correlated with the IOP at 6 months (P = .027). No intraoperative complications were encountered and the procedure was well tolerated. CONCLUSIONS: Fluocinolone acetonide implantation combined with pars plana vitrectomy and silicone oil infusion is feasible and is well tolerated in the management of chronic, refractory ocular hypotony associated with uveitis.

Boston type 1 keratoprosthesis combined with silicone oil for treatment of hypotony in prephthisical eyes.

PURPOSE: To present the outcomes of Boston type I keratoprosthesis (KPro) implantation in combination with pars plana vitrectomy (PPV) and silicone oil for the treatment of hypotony in prephthisical eyes. METHODS: Interventional case series. Thirteen eyes of 13 patients underwent Boston type I KPro implantation, pars plana vitrectomy, and silicone oil placement. Concurrent retinal detachment repair, membrane peel, or intraocular lens explantation were performed if necessary. Inclusion criteria for surgery were eyes with visual acuity worse than 20/400, previous failed penetrating keratoplasty, corneal opacification, visually significant or worsening hypotony, and visual acuity 20/200 or worse in the fellow eye. Outcome measures included Snellen best-corrected visual acuity, anatomic retinal attachment, and complications. RESULTS: At the final follow-up (mean, 24 months; range, 5-66 months), visual acuity was improved in 10 of 13 eyes (77%), stable in 2 of 13 eyes (15%), and decreased in 1 of 13 eyes (8%). All eyes had attached retina with no progression to phthisis bulbi. No intraoperative complications occurred. Postoperative complications included retroprosthetic membrane (7 of 13), KPro melt (1 of 13), KPro leak (1 of 13), KPro infection (1 of 13), vitreous hemorrhage (1 of 13), and retinal detachment (1 of 13). CONCLUSIONS: Boston type I KPro implantation in combination with pars plana vitrectomy and intraocular silicone oil fill can improve vision in most prephthisical eyes with hypotony. Structural findings can also improve.

Treating uveitis-associated hypotony with pars plana vitrectomy and silicone oil injection.

PURPOSE: The purpose of this study was to determine the effect on intraocular pressure (IOP) and visual acuity of treating uveitis-related hypotony in patients with vitrectomy and intravitreal silicone oil injection. METHODS: Patients who underwent pars plana vitrectomy and silicone oil injection for uveitis-associated hypotony treatment were identified retrospectively. The primary outcome was maintaining an IOP of > or =5 mmHg. Visual acuity improvement was defined as an increase in > or =2 lines of acuity. RESULTS: Twelve eyes of 10 patients were identified. Median preoperative IOP was 2 mmHg (range: 0-7 mmHg). Two of 12 eyes had an IOP of > or =5 mmHg at presentation. The number of eyes with an IOP of > or =5 mmHg was 7 of 12 eyes (58%) at 1 month, 4 of 12 eyes (33%) at 3 months, 6 of 12 eyes (50%) at 6 months, and 3 of 9 eyes (33%) at 1 year. Five of 12 eyes (42%) were reinjected between 1 and 3 times with silicone oil for recurring hypotony. Median presenting Snellen visual acuity was counting fingers (range: 20/125 to light perception). Seven of 9 eyes (78%) maintained their preoperative vision at 1 year. CONCLUSION: Intraocular pressure elevated modestly in most patients in this series. However, results were often transient, and some eyes required repeated silicone oil injections. Although silicone oil is reasonable to consider for the treatment and maintenance of IOP in patients with ocular hypotony secondary to uveitis, better treatments are needed.

Hypotonous malignant glaucoma: aqueous misdirection with low intraocular pressure.

Two patients who underwent trabeculectomy and postoperatively manifested axially shallow anterior chamber associated with hypotony but without choroidal effusion are described. The first patient was treated conservatively with topical cycloplegics. The second patient was treated with pars plana anterior vitrectomy. The interventions resulted in deepening of the anterior chamber and posterior rotation of the ciliary body to a natural position as observed by ultrasound biomicroscopy. Intraocular pressure remained low in both cases. These cases demonstrate that hypotony and axial shallowing of the anterior chamber after trabeculectomy can result in a malignant glaucoma-like appearance.

Ocular hypotony: a review.

The etiology, diagnosis, sequelae, and management of ocular hypotony are discussed in this review. Hypotony from decreased production of aqueous is often due to inflammation, medications, or proliferative vitreoretinopathy. Hypotony from aqueous loss may be external, such as following surgery or trauma, or internal, as in cyclodialysis cleft or retinal detachment. Treatment of hypotony is most effective if the underlying cause can be addressed, either surgically or medically. Marked improvement in vision may be achieved if hypotony is reversed.