Sonia N. Yeung

Intracorneal ring segments implantation followed by same-day photorefractive keratectomy and corneal collagen cross-linking in keratoconus.

PURPOSE To evaluate the efficacy of intrastromal corneal ring segments implantation followed by same-day photorefractive keratectomy (PRK) and ultraviolet-A/riboflavin collagen cross-linking (CXL) in patients with keratoconus. METHODS Four patients (five eyes) were included in the study. All patients first underwent femtosecond laser-enabled placement of intracorneal ring segments (Intacs, Addition Technology). Uncorrected (UDVA) and corrected distance visual acuity (CDVA) and keratometry readings remained stable for 6 months. Same-day PRK and CXL were subsequently performed in all patients. RESULTS Six months after Intacs plus PRK/CXL, significant improvements were noted for UDVA, CDVA, spherical equivalent refraction, keratometry, and total aberrations. No patient lost lines of CDVA or developed haze. CONCLUSIONS The combination of intracorneal ring segments implantation followed by sequential same-day PRK/CXL may be a reasonable option for improving visual acuity in select patients with keratoconus.

Evolving indications for and trends in keratoplasty in British Columbia, Canada, from 2002 to 2011: a 10-year review.

Purpose: The aim of this study was to report the evolving indications for keratoplasty and the shift in the type of keratoplasty performed in British Columbia, Canada, over a 10-year period from 2002 to 2011. Methods: This was a retrospective database review of all the records of corneal transplant tissues at the Eye Bank of British Columbia, Canada, from January 2002 to December 2011. The patient demographics, indications, and types of transplant performed were analyzed. Results: A total of 4843 corneal transplants were performed in 3742 patients (1968 male and 1774 female) from January 2002 to December 2011. The number of keratoplasties performed ranged from 420 in 2008 to 578 in 2011. The top 4 indications over the 10-year period were Fuchs endothelial dystrophy (FED; 18.9%), aphakic/pseudophakic bullous keratopathy (17.4%), regraft (17.1%), and keratoconus (15.5%). Penetrating keratoplasty (PKP) accounted for 86.5% (4191 transplants) of all keratoplasties performed. Since the introduction of Descemet stripping automated endothelial keratoplasty (DSAEK) in 2007, there was a significant increase in the number of DSAEKs (P < 0.0001) performed and a statistical decline in the number of PKPs (P < 0.0001) performed. Despite only 30 deep anterior lamellar keratoplasties being performed, an increasing trend was observed after 2008 (P = 0.0087). A decreasing trend in PKPs and an increasing trend in DSAEKs were observed for surgeries performed for FED, aphakic/pseudophakic bullous keratopathy, and regraft. Conclusions: FED has become the top indication for performing a keratoplasty over the 10-year period. There was a shift from PKP to DSAEK performed for endothelial failure. Although the number of deep anterior lamellar keratoplasty surgeries was small, there was a significant increasing trend.

Outcomes of Descemet stripping automated endothelial keratoplasty in patients with previous glaucoma drainage device insertion.

Purpose: To report the outcomes of Descemet stripping automated endothelial keratoplasty (DSAEK) in patients with a previously inserted glaucoma drainage device (GDD). Methods: The clinical records of patients who had DSAEK surgery with a history of GDD insertion were reviewed. Results: Eleven eyes of 10 patients (7 men and 3 women) were included. The mean age for DSAEK surgery was 67.2 ± 20.4 years (range, 22–93 years). The mean follow-up after DSAEK surgery was 20.2 ± 10.7 months (range, 3–37 months). Preoperative mean logarithm of the minimum angle of resolution (logMAR)–corrected distance visual acuity was 1.8 ± 0.6 (range, 20/100 to hand motions), and this improved to 0.9 ± 0.8 (range, 20/40 to hand motions) at the final follow-up (P < 0.01). There was no statistical difference in mean pre-DSAEK versus final post-DSAEK intraocular pressure (P = 0.88). Six of 11 eyes (54.5%) had double GDD insertion before DSAEK surgery. GDD tubes were trimmed in 6 eyes (54.5%), and no eyes required further glaucoma surgical intervention after DSAEK surgery. Postoperative complications included early postoperative graft dislocation in 4 eyes (36.4%) that were successfully repositioned. Four eyes (36.4%) had an episode of endothelial rejection, with 2 patients (18.2%) requiring repeat endothelial keratoplasty for endothelial failure. The mean donor endothelial cell count was 2740 cell per square millimeter preoperatively and reduced to 858 cells per square millimeter at the final follow-up, a significant mean reduction of 69%. This was significantly greater than previously reported endothelial cell loss after DSAEK alone at our institution. Conclusions: Although surgery may be more challenging, the presence of GDD is not a contraindication to DSAEK surgery. In this series, there was a high rate of dislocation that was successfully managed with rebubbling. DSAEK seems to be a reasonable alternative to penetrating keratoplasty for corneal decompensation after GDD.

Combined use of subconjunctival and intracorneal bevacizumab injection for corneal neovascularization.

Purpose: To report on the safety and clinical use of combined subconjunctival and intracorneal bevacizumab for corneal neovascularization. Methods: The charts of 12 consecutive patients with corneal neovascularization who received combined subconjunctival and intracorneal injections of bevacizumab (2.5 mg/0.1 mL) were reviewed. Patients received 1 to 3 injections of 2.5 mg of bevacizumab (1.25 mg/0.05 mL subconjunctival and 1.25 mg/0.05 mL intrastromal). Morphological changes were assessed clinically by 1 investigator. Results: Combined subconjunctival and intracorneal injections of bevacizumab were effective and well-tolerated. No significant ocular or systemic adverse events were observed during 6.4 months (range, 0.25-22 months) of follow-up. All patients showed a reduction in the neovascularized area. Conclusions: Short-term results suggest that combined subconjunctival and intracorneal injections of bevacizumab are an effective method for reducing corneal neovascularization. It may be a useful option or adjunct to other treatments in stabilizing or improving vision.

Long-term outcomes of femtosecond laser-assisted mushroom configuration deep anterior lamellar keratoplasty.

Purpose: To review the long-term outcomes after femtosecond laser (FSL)–assisted mushroom configuration deep anterior lamellar keratoplasty (DALK). Methods: Noncomparative case series of 19 eyes from 19 patients who underwent FSL-assisted mushroom configuration DALK. Results: Data were available for 14 eyes at 1 month, for 14 at 3 months, for 16 at 6 months, for 10 at 9 months, and for 8 at 1 year. Preoperative mean best-corrected visual acuity was 20/108 (range: 20/30–20/400). At 3 months, the mean best-corrected visual acuity was 20/46 (range: 20/25–20/250), and at a mean final follow-up of 13 months (range: 6–29) it was 20/35 (range: 20/15–20/200). The greatest change in mean spherical equivalent was at 3 months [−2.29 diopters (D), range: −7.38 to +3.38 D; from −9.54 D, range: −20.00 to +3.38 D, preoperatively]. There was 56% reduction in mean keratometric cylinder at 6 months (4.00 D, range: 1.04–8.75 D; from 9.13 D, range: 0.50–18.75 D, preoperatively). Complications included 3 cases (15.8%) of small Descemet membrane perforation, none of which required conversion to penetrating keratoplasty; 3 cases (15.8%) of stromal rejection that resolved with topical steroids; and 6 cases (31.6%) of steroid-related intraocular pressure rise that were treated with topical medications. Selective suture removal was initiated a mean of 3.5 months (range: 1.5–6 months) after surgery. Conclusions: The use of the FSL to perform corneal cuts in a mushroom configuration for DALK is reliable and reproducible. Earlier visual rehabilitation may be possible because of the mechanical stability and wound healing advantages of stepped corneal wounds.

Histopathologic features of multiple myeloma involving the optic nerves.

We report a case of optic nerve involvement by multiple myeloma in which progressive visual loss heralded leukemic transformation and intracranial involvement. Imaging showed enhancing nodules in the intracranial segments of both optic nerves posterior to the optic canals and in the anterior optic tract, optic chiasm, and basal leptomeninges. Postmortem histopathologic examination disclosed malignant plasma cells in the subarachnoid spaces around the optic nerves and in the optic nerves. Infarctions were present in both optic nerves near their junction with the globes. Microscopic examination also showed malignant plasma cell infiltration of the leptomeninges of the cerebrum, brain stem, optic chiasm, pituitary gland, cranial bone marrow, and subarachnoid blood vessels. This is the first reported histopathologic examination in conjunction with MRI of multiple myeloma involving the anterior visual pathway. The mechanism of optic neuropathy in this case is probably related to infiltration of the optic nerve meninges by malignant plasma cells and impaired vascular supply caused by aggregated intraluminal plasma cells and monoclonal hypergammaglobulinemia.

Intravitreal bevacizumab for iris neovascularization following proton beam irradiation for choroidal melanoma

OBJECTIVE To evaluate the safety and efficacy of intravitreal injections of bevacizumab as an eye-sparing treatment for iris neovascularization (NVI) following proton beam irradiation for choroidal melanoma. DESIGN Retrospective interventional case series. PARTICIPANTS Four patients who received intravitreal bevacizumab for NVI following proton beam irradiation for choroidal melanoma were identified in the Department of Ophthalmology archives at the University of British Columbia. METHODS Clinical details were reviewed. Long-term follow-up of more than 2 years was detailed for each case. RESULTS All 4 patients responded to a single injection of bevacizumab with regression of NVI. Neovascular glaucoma (NVG) was evident in 3 cases, 2 of which had stable intraocular pressure following treatment. NVI recurred following a single injection in all patients after an interval ranging from 1 month to 12 months. A longer period of regression was seen in patients with fewer systemic neovascular risk factors and earlier treatment. CONCLUSIONS Regression of NVI following proton beam irradiation for choroidal melanoma was seen in all treated patients. Repeated treatments may be required to maintain regression of new vessels. This treatment modality may be a useful eye-sparing adjunct in the prevention and treatment of NVG following proton beam irradiation.

Intracorneal ring segment explantation after intracorneal ring segment implantation combined with same-day corneal collagen crosslinking in keratoconus.

Purpose: To report the outcome and the reversibility of refractive outcomes after intrastromal corneal ring segment (ICRS) explantation in patients with keratoconus treated with ICRS implantation and same-day collagen crosslinking (CXL). Methods: This is a retrospective review of ICRS explantation in 3 eyes of 3 patients with keratoconus that had undergone femtosecond laser–enabled placement of paired ICRS (Intacs) with same-day CXL by a single surgeon between 2008 and 2011. The main outcome measures included baseline/preexplantation/postexplantation visual acuity, refractive error, keratometry, and higher order aberrations. Results: None of the patients lost best-corrected distance visual acuity lines. ICRS can be safely and easily explanted from keratoconic eyes with previous CXL. Some of the topographic benefits gained from ICRS implantation may persist after explantation. Conclusions: Despite the reversal of refractive outcomes, the preservation of topographic changes may occur in some cases after the explantation of 1 or both the segments in patients with keratoconus treated with ICRS implantation with same-day CXL.

Anterior segment uses of bevacizumab.

Purpose of review A significant recent advancement in the treatment of neovascularization of the anterior segment of the eye is the development of antivascular endothelial growth factor (anti-VEGF) therapeutic agents. We present a review of the current knowledge on anti-VEGF therapy with bevacizumab for anterior segment neovascularization. Recent findings A review of the recent peer-reviewed literature reveals an increasing number of experimental and clinical studies on the use of Avastin in both human and animal eye models. Although the numbers are still relatively small, the evidence suggests that bevacizumab may be effective in the treatment of corneal and iris neovascularization. Its effect on primary and recurrent pterygium is more controversial. In general, achievement of vessels regression is usually partial, and recurrence may occur after cessation of treatment. Response to treatment is affected by the chronicity of vessels, their extent, the cause for blood vessels formation, and the route of administration. Summary Effective short-term response together with high patient tolerance to local bevacizumab therapy offer encouraging results for the management of anterior segment neovascular disorders. Although statistically significant regression of vessels has been documented in many studies, the clinical significance of this finding is still a subject of debate.

Applications of the polymerase chain reaction in clinical ophthalmology.

Molecular biology has become a valuable component in many areas of medicine, including ophthalmology. Polymerase chain reaction (PCR) is the most widely used tool. It has proven to be a powerful technique in diagnosis and quantification of microorganisms and antibiotic resistance screening. For a growing number of ophthalmic conditions PCR testing can be conducted. It is therefore important that clinicians be knowledgeable about the indications, strengths, and limitations of the technique. The purpose of this review is to explore the current role of PCR in the diagnosis and management of eye disease.