Large-diameter Penetrating Keratoplasty Research Articles

Ocular manifestations and management of Fusarium and Sarocladium infections

Since 2017, the nomenclature of Fusarium, Acremonium and Sarocladium species have changed, as these morphologically homogeneous, but phylogenetically heterogeneous species and species complexes may be differentiated using MALDI-TOF MS examination, analyzing nucleotic sequences. This resulted in taxonomical changes. We summarize the clinical course, diagnostic and therapeutic options of keratitis caused by Fusarium and Sarocladium. The challenge of Fusarium and Sarocladium keratitis management for an ophthalmologist lies in delayed diagnosis and therapy, fulminant progression and penetration of the Descemet's membrane, restricted availability, poor penetration of antifungal agents and therapy resistance. The diagnosis is based on the clinical history of corneal trauma or contact lens wear, PCR and MALDI-TOF MS, confocal microscopic examination, microbiological culture and light-microscopic analysis of corneal scrapings. As primary conservative treatment, 5% natamycin eye drops have to be used and with results of an antimycogram, topical 1% voriconazole or 0.15-0.25% amphotericin B, in some cases 0.02% polyhexamethylene-biguanide (PHMB) may be applied. Fusarium keratitis may benefit from additional 2 × 200 mg oral voriconazole treatment, daily. In therapy resistant cases, early, large diameter penetrating keratoplasty (PKP) has to be performed, with complete removal of the infected area. With late diagnosis, delayed specific treatment and surgery, mycotic hyphae may penetrate the Descemet's membrane, leading to the loss of vision and enucleation in about every fourth patient. In our paper, we also present the heterogeneous clinical history of five Fusarium and Sarocladium keratitis cases. Orv Hetil. 2019; 160(1): 2-11.

A Novel Approach to the Management of a Progressive Descemet Membrane Tear in a Patient With Keratoglobus and Acute Hydrops

To report a case of corneal hydrops in a patient with keratoglobus that was managed with endothelial keratoplasty to achieve corneal stability and prevent a limbus-to-limbus tear in Descemet membrane. A 30-year-old man with keratoglobus presented with corneal hydrops in his left eye resulting from a central vertical tear in Descemet membrane. His other eye had been previously treated with penetrating keratoplasty using a large graft (an 11-mm donor graft to a 10-mm recipient bed) because of a limbus-to-limbus tear in Descemet membrane without resolution of his edema. An attempt to approximate the edges of the Descemet tear in the left eye by an intracameral air injection failed, and the tear continued to progress peripherally. An endothelial keratoplasty button with anchoring sutures was placed over the Descemet tear because of excessive localized edema. One month after insertion of the sutured endothelial keratoplasty button, the edema had resolved, and 1 year later, the tear remains sealed. The patient's visual acuity improved from counting fingers at 1 foot to 20/100. Reconstitution of the posterior corneal surface in keratoglobus-induced hydrops can be achieved with endothelial keratoplasty over the Descemet tear. Preventing progression of a central Descemet tear is essential to bypass the need for a large-diameter penetrating keratoplasty graft and its complications in a young patient with a history of bilateral corneal hydrops.

Large-Diameter Penetrating Keratoplasty: Indications and Outcomes

To report the indications and outcomes of patients who underwent large-diameter penetrating keratoplasty (LDPK) for the management of peripheral corneal disease. A retrospective chart review and data analysis of patients who underwent LDPK was performed. A retrospective chart review of 35 eyes of 32 patients undergoing LDPK between May 2000 and December 2006 at the Cincinnati Eye Institute/University of Cincinnati was completed. Corneal grafts 8.75 mm or larger were designated as large grafts. Graft diameter ranged from 8.75 mm to 10.0 mm. Indications for cornea transplantation included keratoconus (19), pellucid marginal degeneration (two), keratoconus and pellucid marginal degeneration (five), Fuchs endothelial dystrophy (one), corneal stromal scar (one), postradial keratotomy irregular astigmatism (two), and repeat penetrating keratoplasty (five). No evidence of preoperative stromal neovascularization was seen in any eye. Five of 35 eyes had experienced one previous graft failure. Minimum follow up was 12 months (range, 12-91 months) with a mean follow up of 29.8 months. Preoperative best-corrected visual acuity was 20/100 (range, 20/25 to hand movements), and postoperative best-corrected visual acuity was 20/32 (range, 20/20-20/125). Postoperatively, 43% of patients had 20/40 or better uncorrected visual acuity. Average postoperative manifest cylinder was +2.19 D (range, none to +4.75 D) with 77% of patients having less than +3.00 D of cylinder. The postoperative immunosuppression regimen included topical corticosteroid and topical cyclosporine 0.05%. The incidence of cataract formation in our study was 14.2%. The incidence of secondary glaucoma was 8.8%. Cornea graft rejection was noted in six of 35 eyes with resolution in 4/6. Repeat cornea transplant was required in one of six eyes for severe infectious keratitis, and one of six eyes was lost to follow up. At last follow up, 33 of 35 original grafts were clear with one graft lost to follow up and one eye requiring repeat keratoplasty. No graft rejection was experienced by any patient with a history of prior graft failure. LDPK may result in less postoperative astigmatism without an increased risk of graft failure if managed correctly postoperatively. Topical cyclosporine 0.05% may be a useful adjunct to decrease the incidence of graft rejection and failure. Ophthalmologists performing penetrating keratoplasty should consider a LDPK to reduce postoperative astigmatism and improve visual acuity outcomes in their patients.

An Atypical Presentation of Acanthamoeba Keratitis in a Patient With Keratoconus Treated Briefly With Topical Anesthetic

To present a case of biopsy proven acanthamoeba keratitis requiring penetrating keratoplasty in a patient with keratoconus whose clinical course was remarkable for its lack of ocular injection and pain. The absence of these key findings may have contributed to a delay in diagnosis and a delay in instituting antiamoebic therapy. Case report. A 21-year-old woman who wore soft contact lenses for management of keratoconus presented with a painful suppurative corneal infiltrate and epithelial defect. The patient was initially seen in an emergency department where she was given a bottle of topical anesthetic drops (proparacaine) to use for pain. When she was seen by the authors 18 hr after presenting to the emergency department, the proparacaine was immediately discontinued, and she was treated with fortified antibiotic (vancomycin and tobramycin) eye drops and oral antiviral medications (famciclovir). Despite an initial improvement and complete resolution of ocular discomfort, the patient went on to develop a dense, peripheral stromal infiltrate that failed to improve despite intensive treatment. Confocal microscopy and corneal biopsy were definitive for acanthamoeba infection. The patient subsequently failed medical therapy and underwent large diameter penetrating keratoplasty. The patient has shown no evidence of acanthamoeba recurrence in the corneal graft. Keratoconic patients may have atypical presentations of acanthamoeba keratitis, which may delay diagnosis and institution of medical therapy. Even brief use of topical anesthetics may further complicate the clinical picture.

Large Diameter Therapeutic Penetrating Keratoplasties

Fourteen penetrating keratoplasties were done on ten patients using 9.5 mm or larger diameter grafts. The causes for large grafts were perforation or impending perforation of large descemetoceles due to bacterial ulceration in five eyes, herpes simplex viral keratouveitis in three eyes, severe keratoconjunctivitis sicca with ulceration in four eyes, alkali burn and Mooren's ulcer in one eye each. The average duration of graft clarity was 67.2 days (range 14 days to 6 months). The best spectacle corrected visual acuity range was from l.p. to 20/40. Two patients had recurrent ulceration requiring two large diameter regrafts each. The average period of clarity in these repeated grafts was 26 days. A small graft placed inside of the failed large graft remained clear in 50% of the six eyes which were done for visual restoration. A large diameter penetrating keratoplasty may salvage an eye that might have otherwise been lost and in a few cases provide the opportunity for useful vision.