Prafulla K. Maharana

Evaluation of corneal collagen cross-linking as an additional therapy in mycotic keratitis.

To report the treatment outcomes of mycotic keratitis with collagen cross‐linking.

Outcomes of therapeutic penetrating keratoplasty from a tertiary eye care centre in northern India.

Purpose: The aim was to study the outcomes and results of therapeutic penetrating keratoplasty (Th PK) at a tertiary eye care hospital in northern India. Methods: In this retrospective interventional study, a cohort of 506 eyes that underwent a Th PK for microbial keratitis was evaluated. Th PK was performed in cases of recalcitrant microbial keratitis with impending perforation (descemetocele formation) or perforation (>3 mm). Medical records were reviewed for demographic details, risk factors, ulcer and perforation size, microbiological investigations, size of donor and recipient beds, postoperative complications, and anatomical and visual outcomes. Results: Anatomical success was seen in 454 eyes (89.7%). Preoperatively, the corrected distance visual acuity was <3/60 in 495 eyes (97.8%); after performing the Th PK, the corrected distance visual acuity was <3/60 in 249 eyes (49.2%), 3/60 to 6/60 in 182 eyes (35.9%), and >6/60 in 75 eyes (14.8%). Eyes with smaller grafts (<9 mm) had better anatomical and visual outcomes compared with eyes with larger grafts (9–11 mm; P = 0.03 and >11 mm; P = 0.0). A higher success rate was achieved with pure bacterial or fungal organisms rather than with mixed infections. A higher incidence of secondary glaucoma was seen in eyes with perforated ulcers (29.36%; 111/378) than in eyes without perforation (11.71%; 15/128) (P <.01) and in eyes with larger graft sizes (>11 mm and 9–11 mm) than in eyes with smaller graft sizes (<9 mm) (P <0.01). Conclusions: Th PK has a definitive role in the management of severe and refractory keratitis with a high success in restoring anatomical integrity and providing useful vision. Better outcomes may be achieved with early intervention before perforation or limbal/scleral extension.

Outcomes of corneal collagen crosslinking in pseudophakic bullous keratopathy.

Purpose: The aim was to evaluate the outcomes of corneal collagen crosslinking (CXL) in symptomatic pseudophakic bullous keratopathy (PBK). Methods: In a retrospective noncomparative, interventional case series, we reviewed the records of 50 eyes (50 patients) with symptomatic PBK who underwent CXL. Central corneal thickness (CCT), pain score, best corrected visual acuity (BCVA), and corneal transparency were recorded at baseline; at day 7, day 15; and 1, 3, and 6 months after the CXL. Results: The mean pain score decreased from 8.1 ± 0.6 at presentation to 2.1 ± 0.7 on day 7 (P = 0.0001). A subsequent regression was seen in pain scores over 6 months (5.3 ± 1.5). The mean CCT decreased from a preoperative value of 724.8 ± 78.4 to 694.9 ± 77.9 &mgr;m by the end of the first month (P = 0.0001). The CCT remained stable at subsequent follow-up. The BCVA improved from logarithm of the minimum angle of resolution (log MAR) 2.0 ± 0.5 preoperatively to log MAR 1.8 ± 0.5 by the end of the first month (P = 0.001). The subsequent follow-up showed a progressive deterioration in the BCVA to the preoperative levels at 6 months. Corneal bullae recurred in 44% (22 eyes) at 6 months after an initial disappearance. A significant improvement in the BCVA and a lack of recurrence of bullae were significantly associated with a thinner CCT on presentation. Conclusions: CXL in symptomatic PBK temporarily improves pain without providing long-term improvement in the BCVA. Case selection is important with more effect seen in patients with a thinner CCT at presentation.

Acute corneal hydrops in keratoconus

Acute corneal hydrops is a condition characterized by stromal edema due to leakage of aqueous through a tear in descemet membrane. The patient presents with sudden onset decrease in vision, photophobia, and pain. Corneal thinning and ectasias combined with trivial trauma to the eye mostly by eye rubbing is considered as the underlying cause. With conservative approach self-resolution takes around 2 to 3 months. Surgical intervention is required in cases of non-resolution of corneal edema to avoid complications and for early visual rehabilitation. Intracameral injection of air or gas such as perflouropropane is the most common surgical procedure done. Recent investigative modality such as anterior segment optical coherence tomography is an extremely useful tool for diagnosis, surgical planning, and postoperative follow up. Resolution of hydrops may improve the contact lens tolerance and visual acuity but most cases require keratoplasty for visual rehabilitation.

Anterior Segment Optical Coherence Tomography-Guided Management Algorithm for Descemet Membrane Detachment After Intraocular Surgery.

Purpose: To evaluate the role of anterior segment optical coherence tomography (ASOCT) in the detection and management of Descemet membrane detachment (DMD) in cases of persistent corneal edema after intraocular surgery. An ASOCT-guided new algorithm for the management of such DMDs is described. Methods: Thirty-seven consecutive cases of persistent corneal edema of more than 2-week duration after intraocular surgery were included. All cases referred had no response to medical therapy. ASOCT was performed in all eyes. DMDs that were in the superior half of the cornea with a planar configuration alone were managed using intracameral air, and those with scrolled edges were managed using intracameral 14% perfluoropropane (C3F8). DMDs that were in the inferior half of the cornea with planar or scrolled edges were managed using intracameral C3F8 injection. The parameters evaluated were the type and morphology of DMD, resolution of DMD, and best-corrected visual acuity. Results: Using ASOCT, DMD was found to be present in 25 eyes. All cases had planar edges, and 52% (13/25) cases had scrolled edges. In 48% (12/25) cases, DMD was peripheral. Descemetopexy with intracameral air or 14% C3F8 gas showed resolution in all cases with the mean time to resolution being 16.0 ± 7.1 days. Conclusions: ASOCT is a useful tool for timely diagnosis, characterization, and management of DMD in cases of nonresolving postoperative corneal edema. A new algorithm for intracameral injection of air or C3F8 in these cases helps to defer corneal transplantation.

Management of acute corneal hydrops in ectatic corneal disorders.

Purpose of review The purpose of this review is to outline the risk factors, clinical features, diagnosis, and management of acute corneal hydrops in corneal ectatic disorders. Recent findings The advent of newer investigative modalities aids in diagnosis and planning of treatment in cases of acute hydrops. Although visual outcome does not differ with intervention such as intracameral air/gas injection the duration of symptoms and the risk of complications decrease in comparison with medical therapy alone. Summary The intent of this article is to highlight the various risk factors and the newer diagnostic modalities such as ultra biomicroscopy, anterior segment optical coherence tomography and confocal microscopy in cases of acute corneal hydrops. Further, the conventional as well as the newer treatment modalities are also described. Although newer diagnostic and treatment modalities are found to be useful, the available information in literature is limited. This article will encourage future prospective studies and randomized controlled trials, which may help in finding novel diagnostic and effective therapeutic techniques.

Recent advances in diagnosis and management of Mycotic Keratitis

Mycotic keratitis is a major cause of corneal blindness, especially in tropical and subtropical countries. The prognosis is markedly worse compared to bacterial keratitis. Delayed diagnosis and scarcity of effective antifungal agents are the major factors for poor outcome. Over the last decade, considerable progress has been made to rapidly diagnose cases with mycotic keratitis and increase the efficacy of treatment. This review article discusses the recent advances in diagnosis and management of mycotic keratitis with a brief discussion on rare and emerging organisms. A MEDLINE search was carried out for articles in English language, with the keywords, mycotic keratitis, fungal keratitis, emerging or atypical fungal pathogens in mycotic keratitis, investigations in mycotic keratitis, polymerase chain reaction in mycotic keratitis, confocal microscopy, treatment of mycotic keratitis, newer therapy for mycotic keratitis. All relevant articles were included in this review. Considering the limited studies available on newer diagnostic and therapeutic modalities in mycotic keratitis, case series as well as case reports were also included if felt important.

Diamond knife-assisted deep anterior lamellar keratoplasty to manage keratoconus.

Purpose To evaluate the outcomes of a new surgical technique, diamond knife–assisted deep anterior lamellar keratoplasty (DALK), and compare its visual and refractive results with big‐bubble DALK in cases of keratoconus. Setting Tertiary eyecare hospital. Design Comparative case series. Methods The visual and surgical outcomes of diamond knife–assisted DALK were compared with those of successful big‐bubble DALK. Results Diamond knife–assisted DALK was performed in 19 eyes and big‐bubble DALK, in 11 eyes. All surgeries were completed successfully. No intraoperative or postoperative complications occurred with diamond knife–assisted DALK. Six months after diamond knife–assisted DALK, the mean corrected distance visual acuity (CDVA) improved significantly from 1.87 logMAR ± 0.22 (SD) to 0.23 ± 0.06 logMAR, the mean keratometry improved from 65.99 ± 8.86 diopters (D) to 45.13 ± 1.16 D, and the mean keratometric cylinder improved from 7.99 ± 3.81 D to 2.87 ± 0.59 D (all P=.005). Postoperatively, the mean refractive astigmatism was 2.55 ± 0.49 D and the mean spherical equivalent was −1.97 ± 0.56 D. The mean logMAR CDVA (P = .06), postoperative keratometry (P=.64), refractive cylinder (P=.63), and endothelial cell loss (P=.11) were comparable between diamond knife–assisted DALK and big‐bubble DALK. Conclusions Diamond knife–assisted DALK was effective and predictable as a surgical technique for management of keratoconus cases. This technique has the potential to offer visual and refractive outcomes comparable to those of big‐bubble DALK. Financial Disclosure No author has a financial or proprietary interest in any material or method mentioned.

Ocular allergy and keratoconus

Keratoconus is the most common corneal ectatic disorder, the cause of which is largely unknown. Many factors have been implicated, and the ocular allergy is being one of them. The commonly proposed pathogenesis includes the release of inflammatory mediators due to eye rubbing which may alter the corneal collagen and lead to corneal ectasias. The onset of keratoconus is often early in cases associated with allergy and routine corneal topography may detect subtle forms of keratoconus. These cases may require early keratoplasty and are at an increased risk of having acute corneal hydrops. Surgical outcomes are similar to primary keratoconus cases. However, post-operative epithelial breakdown may be a problem in these cases. Control of allergy and eye rubbing is the best measure to prevent corneal ectasias in cases of ocular allergy.

Deep anterior lamellar keratoplasty for keratoconus: a review.

Abstract: Deep anterior lamellar keratoplasty (DALK) is a surgical technique that involves the removal of pathological corneal stroma down to Descemet membrane and replacing it with a donor cornea. Over the last decade, there has been a paradigm shift in the surgical techniques of DALK, which has made it safer with visual outcomes comparable with penetrating keratoplasty. This review aims to discuss the existing popular techniques of DALK, their advantages and limitations. We will also describe techniques of DALK that are useful in special situations.