Hybrid technique of tuck-in Tenon's patch graft and tissue adhesives and bandage contact lens (TABCL) for large corneal perforation in microbial keratitis

ABSTRACT

We describe the hybrid technique of tuck-in Tenon's patch graft (TPG) and tissue adhesive bandaged contact lens (TABCL) for large corneal perforations (>5 mm) with intact surrounding stroma. Management of large corneal perforation is often challenging, and urgent availability of donor cornea might be difficult; Tenon patch alone does not provide tectonic support; hence, this hybrid technique can be used safely in large perforations. This involves freshening the perforation edges, creating a 3600 stromal pocket, harvesting a Tenon's graft 1 mm oversized, tucking into the pocket, and suturing. Then areas of leakage were noted, and only those areas were supplemented with minimal cyanoacrylate glue (CG) at the graft edges. This technique was used in two eyes, one with a large corneal perforation and intact surrounding stroma and the other with 4 mm corneal fistula post healed keratitis with a failed primary TPG alone, and led to epithelialization and a smooth corneal surface at 6 weeks. The advantages include autologous tissue, cost-effective, easily available, minimal post-operative inflammation, vascularization, and surface irregularity.

Management of acute corneal hydrops - Current perspectives

Acute corneal hydrops (ACH) is a rare but sight-threatening complication of corneal ectasias. We aim to review the current literature on etiopathogenesis, histology, role of ancillary investigations, management, and outcomes of ACH by classifying the various management strategies based on their site of action and the underlying mechanism. A review of the literature was conducted by searching the following databases: PubMed (United States National Library of Medicine), Embase (Reed Elsevier Properties SA), Web of Science (Thomson Reuters), and Scopus (Elsevier BV) till April 2023. The literature search used various combinations of the following keywords: acute corneal hydrops, keratoconus, ectasia, management, keratoplasty. Nine hundred eighty-three articles were identified based on the above searches. Case reports which did not add any new modality of treatment to the existing literature, articles unrelated to management, those with no full text available, and foreign-language articles with no translation available were excluded. Eventually, 75 relevant articles that pertained to the management of ACH were shortlisted and reviewed. Recent studies have described newer surgical interventions like full-thickness or pre-Descemetic sutures, thermokeratoplasty, and plasma injection that aim to close the posterior stromal break. Posterior lamellar keratoplasties act by replacing the posterior torn Descemet's membrane (DM), and early deep anterior lamellar keratoplasty (DALK) has been attempted to combine the correction of the anatomical defect and visual rehabilitation in a single surgery. These surgical interventions may help by reducing the scarring and increasing the number of patients who can be visually rehabilitated with contact lenses rather than keratoplasty.

Toxic anterior segment syndrome (TASS): A review and update

Toxic anterior segment syndrome (TASS) is an acute, sterile, postoperative inflammatory reaction of the anterior segment without vitreous involvement, following an uncomplicated and uneventful ocular surgery, having broad and multiple etiologies. The symptoms of decreased visual acuity and ocular discomfort generally occur within the first 12-48 h after intraocular surgery. The clinical signs include prominent limbus-to-limbus corneal edema, anterior chamber cells, aqueous flare, fibrinous inflammation, and/or keratic precipitates. There can be sight-threatening complications of TASS, such as permanent corneal decompensation, intractable glaucoma, and cystoid macular edema. The causes of TASS are emerging and being reported, so are the newer treatment options for managing the inflammation and its complications. Prevention guidelines for TASS are being updated, and a traceability system for surgical instruments and intraocular fluids used during the surgery is being perpetually developed. It is important to recognize TASS and start treatment on an immediate effect. Hereby, we review the literature on TASS, emphasizing its etiology, pathophysiology, management, prognosis, complications, and the importance of prevention as well as prompt recognition.

Management and prevention of corneal graft rejection

The management of an episode of corneal graft rejection (CGR) is primarily by corticosteroids. Immunomodulators are useful for long-term immunosuppression and in dealing with cases of high-risk (HR) corneal grafts. The classical signs of CGR following penetrating keratoplasty (PKP) include rejection line, anterior chamber (AC) reaction, and graft edema. However, these signs may be absent or subtle in cases of endothelial keratoplasty (EK). Prevention of an episode of graft rejection is of utmost importance as it can reduce the need for donor cornea significantly. In our previous article (IJO_2866_22), we had discussed about the immunopathogenesis of CGR. In this review article, we aim to discuss the various clinical aspects and management of CGR.

Cataract surgery outcomes in pediatric patients with systemic comorbidities

Purpose

The aim of the study was to evaluate the outcomes of cataract surgery in patients of the pediatric age group with systemic comorbidities.

Methods

Medical records of 54 eyes (30 patients) of the pediatric age group with systemic comorbidities who had undergone cataract surgery in a tertiary-care center were reviewed. The following parameters were recorded: systemic comorbidity; toxoplasmosis, rubella, cytomegalovirus, herpes simplex, HIV (TORCH) profile, best spectacle-corrected visual acuity (BSCVA), strabismus, nystagmus, and cataract morphology.

Results

Thirty patients with a mean age of 55 months (9 months-14 years) were included. On average, every child was seen by three physicians, and the mean duration between the first visit to a physician and presentation to our center was 2.23 ± 0.67 years. The various causes for delay in referral include multiple referrals due to a lack of general anesthesia services in 78% of cases, a long waiting list at the referral hospital in 35% of cases, and a lack of awareness at the primary-care physician level in 50% of cases. The mean BSCVA at presentation was 1.4 logMAR (0.3 to 3 logMAR). The most common cataract morphology was that of zonular cataract (31.48%; 17/54). Strabismus and abnormal eye movements were observed in 27.7% (15/54) and 33.3% (18/54) of eyes, respectively. Various systemic associations were periventricular leukomalacia (12/30), Down's syndrome (6/30), seizure disorder (6/30), cardiac valvular anomalies (6/30), Marfan's syndrome (4/30), hypothyroidism (4/30), rubella (3/20), cytomegalovirus (3/20), cerebral palsy (2/30), nephrotic syndrome (2/30), Type 1 diabetes mellitus (1/30), microcephaly (1/30), cryptogenic West syndrome (1/30), congenital rubella syndrome (1/30), and Tourette syndrome (1/30). The mean postoperative corrected distance visual acuity (CDVA) at 2-year follow-up improved to 1.0 logMAR (0 to 3 logMAR). No postoperative complications were reported at the final follow-up. Around 70% of the parents reported improvement in their child's psychomotor skills.

Conclusion

Intellectually impaired pediatric patients with cataract should be operated upon whenever there is a presence of infrastructure, and unnecessary delay in surgery should be avoided by referring the patient to higher centers. Even though objective improvement in visual acuity was suboptimal, there was definitely an improvement in the psychomotor skills of the patients.

A review of techniques and outcomes of endothelial keratoplasty in congenital hereditary endothelial dystrophy

Congenital hereditary endothelial dystrophy affects the Descemet membrane and endothelium, resulting in corneal decompensation. Penetrating keratoplasty (PKP) has been the gold-standard surgical management until recently; however, at present, endothelial keratoplasty (DSEK/DSAEK/n-DSEK: Descemet-stripping or non-Descemet stripping endothelial keratoplasty and DMEK/n-DMEK: Descemet membrane endothelial keratoplasty) is being preferred due to lesser intraoperative and postoperative complications, early visual recovery, and comparable visual outcomes. Endothelial keratoplasty (EK) can be challenging, especially in pediatric eyes with CHED due to smaller eyeballs, shallow anterior chambers, phakic status, and poor intraoperative visibility due to thick and hazy corneas. A total of 198 articles matched our search strategy. After screening for duplication and going through the titles and abstracts, 12 relevant original articles, one case series, and six case reports were included in this review. Various surgical modifications have to be adopted in comparison to adult eyes to overcome the aforementioned difficulties. Regardless, studies have shown favorable visual outcomes with better graft survival and fewer complications in eyes that underwent EK compared to PKP. Hence, timely surgical intervention and strict amblyopia management can result in better final visual outcomes. The purpose of this review is to summarize various intraoperative difficulties and the surgical modifications required, different surgical techniques, visual and graft-related outcomes, and various complications of EK in CHED eyes.

Ocular manifestations in Kindler syndrome

We aimed describe the chronic ocular sequelae of Kindler syndrome. All cases of Kindler syndrome with ocular involvement that presented to a tertiary eye care center were included. Three cases of Kindler syndrome with ocular changes were reviewed. Case 1 (10 years, female) had recurrent epithelial breakdown with severe dry eye and corneal opacity secondary to keratitis. Case 2 (28 years, male) had symblepharon , ocular surface keratinization , and severe dry eye. Case 3 (16 years , female ) had partial limbal stem cell deficiency with dry eye. All cases were treated with topical lubricants, short course of low-potency steroids and immuno-modulators. Attention must be paid to the eye in addition to the oro-an-genital mucosa to avoid longterm ocular sequelae.

Outcomes of surgical intervention in cases of ectopia lentis

Purpose:

To evaluate the outcomes of surgical intervention in cases of ectopia lentis.

Methods:

This retrospective study included all cases of ectopia lentis that presented between June 2015 and March 2019 in a tertiary care center. They were reviewed retrospectively. The corrected distance visual acuity (CDVA), severity of lens subluxation, type of surgery, intra-operative and post-operative complication, and specular count were recorded.

Results:

Seventy-eight eyes of 57 cases with a mean age at surgery of 14.73 years were analyzed. Intra-lenticular lens aspiration was the most common (n-62/78; 79.5%) surgical procedure followed by lens aspiration, intra-capsular cataract extraction, phaco-aspiration, and pars-plana lensectomy. Simultaneous intra-ocular lens (IOL) implantation was performed in 46.2% (n-32/78) of the eyes. The mean CDVA improved from 0.85 ± 0.55 logMAR to 0.44 ± 0.29 logMAR at 6 weeks follow-up. The post-operative CDVA was significantly better in the pseudo-phakic group compared to the aphakic group (p-0.02). The patient’s age at the time of surgery and the degree of subluxation did not impact the final visual outcome. Intra-operative complication included vitreous hemorrhage (n-1) and lens matter drop (n-1). Post-operative complications were noted in 26.9% of the eyes (n-21/78) with a higher complication rate in the pseudo-phakic group (p-0.00). A second intervention was required in 7.7% of the eyes (n-6/78).

Conclusion:

Age and degree of subluxation at the time of surgery do not influence the final visual outcome in cases of ectopia lentis undergoing lens extraction surgery. IOL implantation results in better visual outcomes but is associated with a high complication rate.

Spectrum of bacterial keratitis in North India: A retrospective analysis of six years at a tertiary care eye center

Purpose

To analyze the pattern of bacterial pathogens causing infective keratitis and their resistance to the recommended antibiotics over six years.

Methods

It was a retrospective study of 9,357 cases of bacterial keratitis from January 2015 to December 2020, at a tertiary care ophthalmic center. A total of 9,547 corneal specimens were obtained from the study subjects. Demographic details of the patients, pathogenic bacteria isolated, and their antimicrobial susceptibility were noted and analyzed.

Results

Bacterial pathogens were identified in 23.52% of the specimens. The most common isolates were coagulase-negative Staphylococci (60.75%), followed by Pseudomonas aeruginosa (14.23%), Staphylococcus aureus (13.92%), gram negative bacilli of the family Enterobacterales (8.64%), Streptococcus spp. (1.72%), Acinetobacter spp. (0.13%), and other non-fermenting gram-negative bacilli (0.57%). In Staphylococci, 55-80% of isolates were resistant to erythromycin, and 40-70% to fluoroquinolones, while no resistance was observed against vancomycin. 40-60% of isolates of P. aeruginosa were resistant to cephalosporins, 40-55% to fluoroquinolones, and 30-60% to aminoglycosides. Also, 40-80% of isolates of Enterobacterales were resistant to cephalosporins, and 50-60% to fluoroquinolones. Most gram-negative isolates were susceptible to carbapenems and polymyxin B.

Conclusion

To the best of our knowledge, our study is the largest compilation of microbiological profile of bacterial keratitis from North India. It highlights the current trend of the bacterial pathogens that cause infectious keratitis. Staphylococci and Pseudomonas were found to be the most common pathogens. Increased resistance was seen against some of the commonly prescribed empirical antibiotics. Such evidence is useful for restructuring the empirical prescription practices from time to time.

Management of descemetocele: Our experience and a simplified treatment algorithm

Purpose:

To formulate a treatment algorithm for the management of descemetocele.

Methods:

This was a prospective interventional study that was conducted at a tertiary eye-care center. All consecutive cases of descemetocele during the study period (April 1, 2017–March 31, 2018) were evaluated for the following parameters: age, sex, previous medical or surgical therapy, risk factors, preexisting ocular diseases, location, site and size of descemetocele, interventions undertaken, visual acuity, and the fellow eye status. The surgical modalities and fellow eye status were correlated individually with therapeutic and functional outcomes, based on which a treatment algorithm was formulated.

Results:

The study included 24 eyes of 24 patients (19M, 5F) with a median age of presentation of 45 years. The mean follow-up duration was 6.79 ± 3.97 months (3–12 months). The most common cause of descemetocele was microbial keratitis (66.66%), and most cases were central (50%), small (58.33%), and non-perforated (79.16%). The surgical interventions undertaken were cyanoacrylate glue (CG, 37.5%), penetrating keratoplasty (PKP, 33.33%), patch graft (16.66%), and deep anterior lamellar keratoplasty (DALK, 12.5%). Therapeutic success was noted in 13/24 eyes (54.16%). Final visual acuity > 3/60 was seen in 25% cases. Suboptimal therapeutic (P = 0.07) and visual (P = 0.34) outcomes were noted in subjects with non-functional fellow eye.

Conclusion:

PKP was preferred for descemetoceles with active microbial keratitis and extensive infiltrates, while CG and DALK were undertaken for healed microbial keratitis, neurotrophic keratitis, and ocular surface disorders with partial limbal stem cell deficiency (LSCD). For total LSCD, amniotic membrane graft was preferred.

Surgical outcomes of concomitantly performed penetrating keratoplasty with intrascleral haptic fixation

Purpose:

To describe the surgical results of concomitantly performed optical penetrating keratoplasty (PKP) with glued intrascleral haptic fixation (ISHF).

Methods:

Retrospective review of 18 patients (15–72 years) with best-corrected visual acuity (BCVA) of ≤1/60 subjected to unilateral concomitant optical PKP with ISHF and followed up for 13.11 ± 5.83 months (6–26 months) was undertaken.

Results:

The most common diagnoses were failed PKP (9/18, 50%) followed by aphakic bullous keratopathy (5/18, 27%). Preoperative glaucoma, peripheral anterior synechiae (PAS), and deep vascularization were present in 7/18 (38.88%), 12/18 (61.11%), and 5/18 (27.77%) patients, respectively. Intraoperatively, concomitant procedures such as pupilloplasty and intraocular lens explant were undertaken in 5/18 (27.277%) patients and 1/18 patients (5.55%) experienced suprachoroidal hemorrhage. At final follow-up, BCVA was ≥6/60 in 50% patients (mean astigmatism: 4.79 ± 1.68D), and 55.55% cases experienced graft failure (90% failed within one year of surgery). The most common causes of graft failure were glaucoma (50%), glaucoma with rejection (20%), rejection (10%), retinal detachment (10%), and suprachoroidal hemorrhage (10%). The ODDS ratio (OR) of having graft failure with the following factors was postoperative secondary interventions (OR: 6), postoperative complications (OR: 2.25), prior failed graft (OR: 1.8), preoperative PAS (OR: 1.75), intraoperative concomitant procedures (OR: 1.5), preoperative glaucoma (OR: 1.33), previous surgeries (OR: 1.24), and deep corneal vessels (OR: 0.66).

Conclusion:

All patients underlying PKP combined with glued ISHF must be counseled about suboptimal surgical outcomes. Emphasis is laid on appropriate case selection and stringent follow-up during the first year after surgery. Secondary interventions should be undertaken cautiously and judiciously in these patients.

Fungal keratitis: A review of clinical presentations, treatment strategies and outcomes

Infectious keratitis is a significant cause of corneal blindness worldwide. Although less prevalent in the developed world, cases of fungal keratitis account for almost half of all keratitis cases, occurring in the developing countries. These cases are one of the most refractory types of infectious keratitis and present various challenges to the treating physician such as delayed presentation, long waiting time for culture positivity, limited availability effective antifungal drugs, prolonged duration for response to therapy, a highly variable spectrum of anti-fungal drug sensitivity and a high recurrence rate following keratoplasty. The advent of rapid diagnostic tools, molecular methods, in vitro anti-fungal drug sensitivity testing, alternatives to natamycin, targeted drug delivery and most importantly the results of large randomized controlled trials have significantly improved our understanding and approach towards the diagnosis and management of cases with fungal keratitis. Overall, Aspergillus and Fusarium species are the most common causes ones of fungal keratitis. History of antecedent trauma is a significant predisposing factor. Corneal scrapings for microscopic evaluation and culture preparation, is the standard of care for establishing the diagnosis of fungal keratitis. Molecular identification of cultures offers accurate identification of fungal pathogens, especially the rare species. Natamycin is an approved first-line drug. Voriconazole is the best alternative, especially for non-fusarium cases. Management involves administration of drugs usually by a combination of various routes, the treatment regimen being individualized depending upon the response to therapy. Photodynamic therapy is a newer treatment modality, being tried for non-responsive cases, before resorting to a therapeutic graft.

Evaluation of various preservation media for storage of donor corneas

Purpose

To compare the physical and microbiological characteristics of McCarey-Kaufman (MK), Cornisol, and Optisol-GS media and evaluate the outcomes of keratoplasty performed using corneas stored in these three media.

Methods

The study involved 60 donor corneas which were distributed in 3 groups: MK, Cornisol, and Optisol-GS. Corneas in these groups were further analyzed based on the type of keratoplasty performed (full thickness versus endothelial keratoplasty). At baseline, the endothelial cell density and death to preservation time of donor corneas were recorded. Following keratoplasty, patients were evaluated on day 1, at 1 month, 3 months, and 6 months follow-up. Outcomes were assessed in terms of corrected distance visual acuity (CDVA), endothelial cell density, percentage endothelial cell loss, and corneal thickness. The storage media were also assessed for their physical quality and their microbiological characteristics.

Results

Physical characteristics of all three media were found to be within normal limits. Mean CDVA was comparable among the 3 groups at 6-month follow-up. The absolute endothelial cell count values were significantly lower for corneas stored in MK medium (1873.7 ± 261.1 cells/mm²) compared to the Cornisol (2085.0 ± 230.3 cells/mm²) and Optisol-GS media [(2180.3 ± 217.2 cells/mm²) (P = <0.001)]. Corneas stored in Optisol-GS medium were significantly thinner at 1-month follow-up with no significant difference at 6 months (P = 0.66).

Conclusion

Optisol-GS and Cornisol media were found to preserve endothelial cell density better and stabilize corneal thickness earlier as compared to the MK medium. However, the functional outcomes were comparable among the three groups.

Role of therapeutic contact lens following Descemet's stripping automated endothelial keratoplasty: A randomized control trial

Purpose

Therapeutic contact lenses (TCL) are known to help in epithelial healing and decreasing pain after various corneal surgeries. However, literature lacks any data describing their use following Descemet's stripping automated endothelial keratoplasty (DSAEK) where intraoperative epithelial debridement is commonly performed. Here we study the efficacy and safety of TCL in patients undergoing DSAEK.

Methods

In this prospective, randomized, controlled clinical trial. 40 eyes of 40 patients of pseudophakic bullous keratopathy undergoing DSAEK were enrolled and randomized into two groups, control (no TCL) and test (TCL). Primary outcome was time taken for epithelial healing and secondary outcomes were postoperative pain score, graft attachment, best spectacle-corrected visual acuity, and endothelial cell loss at 3 months.

Results

Average time taken for epithelial healing was 3.35 ± 0.49 days in the test group and 4.95 ± 1.05 days in the control group (P < 0.001). Average pain scores in first operative week were significantly lower in the test group as compared to control (P < 0.001). Graft detachment occurred in eight patients in control group and two in test group (P = 0.03). Both rebubbling rates and average endothelial cell loss at 3 months were higher in the control group with P = 0.07 and 0.06 respectively. No contact lens-related adverse effects were noted during the study period.

Conclusion

Use of TCL in DSAEK leads to faster epithelial healing and lesser postoperative pain. In addition, it may also contribute to lower rebubbling rates and endothelial cell loss.

Pediatric Keratoconus: Topographic, Biomechanical and Aberrometric Characteristics

PURPOSE

This study sought to evaluate the demographic profile, clinical features, topographic features, and biomechanical and aberrometric characteristics in pediatric keratoconus (KC).

DESIGN

Cross-sectional study.

METHODS

Pediatric KC cases <18 years of age were evaluated at a tertiary hospital. Main outcome measurements were demographic profile, clinical features, visual acuity, corneal topography, aberrometry, and biomechanical and confocal microscopy findings.

RESULTS

A total of 116 eyes of 62 consecutive patients were recruited with a mean ± age of 14.7 ± 2.77 years (range: 8-18 years); 46 of 62 (88%) were males; 57 of 62 cases (92%) had bilateral disease; 53 of 116 eyes (46%) had progressive KC; and 9 of 116 eyes (8%) had acute hydrops. Systemic associations were found in 6 of 62 patients (9.7%) and ocular associations in 77 of 116 eyes (66.3%); 68 of 116 eyes (58.6%) had associated vernal keratoconjunctivitis (VKC). Among eyes with VKC, 29 of 68 eyes (46%) were in stage IV KC, versus 25% of eyes with no VKC (P = .004). The mean ± SD refractive spherical equivalent was -4.72 ± 3.32 diopters (D), and refractive astigmatism was 3.69 ± 3.09 D. The mean values of maximum keratometry, thinnest pachymetry, and corneal higher-order aberrations were 60.89 ± 10.9 D, 396.05 ± 95.03 μm, and 1.18 ± 1.2 μm, respectively. Values of corneal hysteresis and corneal resistance factor correlated with the stage of KC (r = -0.26; P = .007).

CONCLUSIONS

Pediatric KC was commonly associated with VKC in this cohort. Eyes with VKC had more severe KC than those without VKC. Nearly half of the patients presented with progressive disease. Corneal biomechanical changes correlated well with stage of KC in this pediatric age group.

Outcomes of Cultivated Oral Mucosal Epithelial Transplantation in Eyes With Chronic Stevens-Johnson Syndrome Sequelae

PURPOSE

To study the outcomes of cultivated oral mucosal epithelial transplantation (COMET) in eyes with chronic Stevens-Johnson syndrome (SJS) sequelae.

DESIGN

Prospective interventional case series.

METHODS

Forty-five eyes of 41 patients with chronic SJS sequelae were recruited and evaluated from 2013 to 2017 in an institutional setting. All patients underwent COMET, with an aim of fornix reconstruction and visual rehabilitation. Change in corrected distance visual acuity (CDVA), severity scores of various ocular surface parameters, and the occurrence of complications were documented during a follow up period of 2 years. Attainment and maintenance of a stable ocular surface, as assessed by change in the ocular surface severity scores was the primary outcome measure, while change in CDVA was the secondary outcome measure.

RESULTS

The mean preoperative CDVA was 2.7± 0.5 logMAR, which improved to 1.5± 0.7 logMAR and 1.49± 0.98 postoperatively, at 1- and 2-year follow-up visit. Overall, 82.2% eyes (37/45) had improvement in visual acuity, 13.3% (6/45) experienced no change, whereas 2 eyes (4.4%) had worsening of visual acuity. The total ocular surface severity scores improved from a mean preoperative value of 29.1± 9.7 to 18.7± 7.2 postoperatively, at 2-year follow-up. Two eyes developed persistent epithelial defects, with progression to corneal melting requiring keratoplasty.

CONCLUSIONS

COMET allows successful and sustained restoration of ocular surface anatomy with functional improvement, in eyes with chronic sequelae of SJS.

Complications of small incision lenticule extraction

The procedure of small incision lenticule extraction (SMILE) was introduced in 2011, and since then there has been an increase in the number of cases undergoing this procedure worldwide. The surgery has a learning curve and may be associated with problems in the intraoperative and postoperative periods. The intraoperative problems during SMILE surgery include the loss of suction, the occurrence of altered or irregular opaque bubble layer and black spots, difficulty in lenticular dissection and extraction, cap perforation, incision-related problems, and decentered ablation. Most of the postoperative problems are similar as in other laser refractive procedures, but with decreased incidence. The identification of risk factors, clinical features, and management of complications of SMILE help to obtain optimum refractive outcomes.

Cataract surgery outcomes in eyes with chorioretinal coloboma

PURPOSE

To evaluate the outcomes of cataract surgery in patients with chorioretinal coloboma.

SETTING

Tertiary eyecare center, New Delhi, India.

DESIGN

Retrospective case series.

METHODS

Medical records of patients with chorioretinal coloboma having cataract surgery between January 2016 and May 2018 were reviewed. The corrected distance visual acuity (CDVA), grade of cataract, type of chorioretinal coloboma, type of surgery, postoperative CDVA, and complications were recorded.

RESULTS

Thirty-eight patients with a mean age at surgery of 36.7 years were included. The mean CDVA at presentation was 1.83 logarithm of the minimum angle of resolution [logMAR] ± 0.31 (SD). Advanced nuclear sclerosis occurred in 61.4% of cases and lens subluxation in 10.2% of cases. Phacoemulsification (56.4%) was the most commonly performed cataract surgery followed by lens aspiration (12.8%) and extracapsular cataract surgery (12.8%). Uneventful cataract surgery with intraocular lens (IOL) implantation was performed in 69.2% of cases. Intraoperative complications included 7 cases of bag dialyses, 3 of posterior capsule ruptures, and 1 of capsulorhexis extension. The mean postoperative CDVA at 6 weeks and 1 year was 1.64 ± 0.51 logMAR and 1.51 ± 0.58 logMAR, respectively. Postoperative complications included 11 cases each of raised intraocular pressure and corneal edema; 2 cases each of IOL decentration, capsule phimosis, and corneal edema; and 1 case of posterior capsule opacification. A second intervention was required in 4 cases (2 endothelial keratoplasties, 1 IOL explantation, 1 neodymium:YAG capsulotomy).

CONCLUSIONS

Cataracts in patients with chorioretinal coloboma are usually advanced compared with age-matched patients with senile cataract. Delayed surgery results in suboptimum outcomes; thus, surgery should be scheduled as soon as possible after the cataract is documented.

Surgical alternatives to keratoplasty in microbial keratitis

Penetrating keratoplasty is often required in microbial keratitis not responding to the standard treatments available or the development of complications like corneal perforation. Performing keratoplasty in microbial keratitis has several challenges, the major ones being the availability of donor corneal tissue and the poor success of the corneal graft performed in such a setting. For overcoming these challenges, several alternatives to keratoplasty have been described. Broadly, these options could be categorized into autologous tissues such as conjunctival and tenon tissue, synthetic products like tissue adhesives and therapeutic contact lenses, or biological tissues like amniotic membrane graft. These alternative modalities are not universal. They have their specific indications in microbial keratitis. Most of these alternatives are useful only for small corneal perforations. While autologous tissues are cost-effective and readily available, lack of tectonic support is a significant limitation. Tissue adhesives are excellent alternatives in terms of tectonic support, but surface irregularity and tissue reaction are their potential limitations. The amniotic membrane is useful for small corneal perforations, but availability, cost, and poor tectonic support restrict its use. Herein, we discuss these various alternatives to keratoplasty in microbial keratitis, their indications, advantages, disadvantages, and the various techniques of performing these procedures.

Microscope Integrated Intraoperative Optical Coherence Tomography-Guided DMEK in Corneas with Poor Visualization

PURPOSE

To assess the utility of microscope-integrated intraoperative optical coherence tomography (Mi-OCT) for performing Descemet membrane endothelial keratoplasty (DMEK) in corneas with poor visualization.

METHODS

It is a prospective interventional case series that included 25 consecutive cases of corneal decompensation with poor visualization that underwent Mi-OCT-guided DMEK at a tertiary eye care centre. The main outcome measures were graft attachment on day 3 and requirement for re-bubbling.

RESULTS

The etiology for corneal decompensation was pseudophakic bullous keratopathy (n=17), Fuchs endothelial corneal dystrophy (n=4), failed graft (n=2), iridocorneal endothelial syndrome (n=1) and failed Descemet stripping automated endothelial keratoplasty (n=1). Complete graft attachment was noted in 72% of cases. Graft detachment was noted in 16% of cases which required re-bubbling. No intervention was done for shallow peripheral detachment (n=2) and peripheral Descemet membrane (DM) fold (n=1). All grafts were attached at six-months follow-up. The mean corrected distance visual acuity and central corneal thickness improved from 1.4 ± 0.5 logMAR and 799.6 ± 110.9 µm at baseline to 0.3 ± 0.3 logMAR and 536.28 ± 11.44 um at six months. Mi-OCT was helpful in visualizing areas of peripheral anterior synechiae, missing DM, retained DM tags after descemetorhexis, DMEK roll configuration and orientation in the injector and anterior chamber, interface fluid and peripheral folds in the DMEK graft.

CONCLUSION

Mi-OCT helps in identification of the anatomy and dynamics of the host DM, DM roll and anterior chamber in cases with poor visualization and is a useful tool while performing DMEK in such cases.

Intraoperative optical coherence tomography-guided release of lenticulo-corneal adhesion and lens aspiration in anterior dislocation of lens with corneal edema

Purpose:

To describe the outcome of microscope integrated optical coherence tomography (MiOCT) guided removal of lenticulo-corneal adhesion and intralenticular lens aspiration (ILLA) in cases with anterior dislocation of the crystalline lens and corneal edema.

Methods:

MiOCT-guided ILLA was performed in three eyes of two cases of homocystinuria with spontaneous anterior dislocation of lens and corneal edema. Lenticulo-corneal adhesion was noted intraoperatively, which was not apparent pre-operatively. The lenticulo-corneal adhesion could be successfully peeled using intravitreal forceps and viscodissection with visco-dispersive viscoelastic under the guidance of MiOCT.

Results:

In all cases, the lenticulo-corneal adhesion could be successfully removed without any complication such as Descemet tear or worsening in corneal edema. Improvement in visual acuity was noted in all cases with resolution in corneal edema by 1 week.

Conclusion:

MiOCT-guided ILLA can be extremely useful in cases of lenticulo-corneal adhesion especially in cases with corneal edema.

Descemet membrane detachment

Descemet membrane detachment (DMD) is a potential vision-threatening complication that occurs most commonly after cataract surgery. DMD has also been reported to occur in various other surgeries such as keratoplasty, iridectomy, vitrectomy, trabeculectomy, holmium laser sclerostomy, alkali burn, and viscocanalostomy. Major risk factors include advanced age, preexisting endothelial diseases like Fuchs dystrophy or abnormality in the Descemet membrane and stromal interface, hard cataract, prolonged surgical time, ragged clear corneal incisions, and inadvertent trauma with blunt instruments or phacoemulsification probe. Most DMDs are peripheral and resolve spontaneously. Large, central DMDs if not managed appropriately may lead to corneal decompensation and opacification. Several authors have classified DMD depending on its configuration, height, extent, length, and position with respect to pupil. Anterior segment optical coherence tomography has been used to confirm and classify DMD and can also aid in deciding the management plan. Spontaneous reattachment of the DM with conservative management may occur in cases with small, peripheral, planar DMD with nonscrolled edges. Cases with nonplanar, central DMD, scrolled edges, and length >2 mm, however, have to be managed surgically. Descemetopexy is the gold standard for the management of DMD. Other management options include mechanical tamponade, suture fixation, descemetotomy, interface drainage, and keratoplasty. Prompt diagnosis and timely management often leads to a good visual outcome.

Infectious Keratitis Caused by Rare and Emerging Micro-Organisms

PURPOSE

To provide a comprehensive review of rare and emerging micro-organisms causing infectious keratitis.

MATERIAL AND METHODS

A literature search was performed using PubMed Medline, Cochrane Library Database, EMBASE and Scopus (1960 onwards), using the terms: keratitis caused by rare pathogens; mycotic keratitis; fungal keratitis; bacterial keratitis; infectious keratitis; infective keratitis; atypical fungal keratitis; fungal keratitis caused by rare organisms; fungal keratitis caused by rare ocular pathogen; atypical bacterial keratitis; bacterial keratitis caused by rare organisms; bacterial keratitis caused by rare ocular pathogen. All relevant articles were included in this review.

RESULTS

A total of 1232 articles matched our search strategy of which 124 articles were included in this mini-review. The rare and emerging bacteria causing keratitis include atypical mycobacteria, Nocardia spp., Chrysebacterium spp., Delftia acidovorans, Kocuria spp., Enterococcus spp., Bartonella henslae, Achromobacter spp. and others. The rare and emerging fungi causing keratitis include Pythium spp., Alternaria spp., Acremonium spp., Cladosporium spp., Curvularia spp., Bipolaris spp., Microsporidia spp., Pseudallescheria spp., Colletotrichum spp., and others. The clinical presentation of these cases is variable. While a few organisms produce characteristic clinical features, rest present similar to bacterial or fungal keratitis with variable response to routine treatment. A strong degree of suspicion is therefore essential for its diagnosis. Special investigations like polymerase chain reaction, gene sequencing, mass spectroscopy and enzyme-linked immunosorbent assay are required for accurate identification of these organisms. Culture-sensitivity is extremely useful as drug resistance to routinely used anti-microbial drugs is common. Prognosis is usually poor for keratitis with Pythium spp., Pseudallescheria spp., Arthrographis spp., Purpureocillium spp., Kociria spp. and Achromobacter spp.

CONCLUSION

Keratitis caused by rare and emerging micro-organisms must be suspected in cases where the infection runs an unusual course or shows a poor response to standard anti-microbial drugs. Early diagnosis and timely treatment hold the key for a good outcome.

Procurement, storage and utilization trends of eye banks in India

Purpose:

To study the trends in collection, storage and utilization of donor corneas in eye banks in India.

Methods:

The data was collected from 12 eye banks in India that collected more than 1000 corneas per year. The retrospective analysis of the parameters like characteristics of the donor and the host, storage media used, number of eyes collected, number of eyes utilized, causes of non-utilization of the tissue and the procedures performed was done.

Results:

A total of 20,564 eyes were collected by the 12 eye banks during the year 2013–2014. Voluntary eye donation (VED), and hospital cornea retrieval program (HCRP) contributed to 59.6% and 40.4% of tissue procurement respectively. Whole globe enucleation (52.3%) was more commonly performed as compared to in-situ excision of the donor corneas. The most commonly used storage media at all eye banks was McCarey-Kaufman (MK) media (83.3%). The utilization rate of the donor eyes was 50.5%. The most frequent indication for corneal transplantation was infection (active infection - 33.13%, healed infection - 10.78%) followed by Pseudophakic bullous keratopathy (PBK) (13.57%). Full thickness keratoplasty (optical penetrating keratoplasty - 47.23%, therapeutic penetrating keratoplasty - 31.74%) was performed most often followed by endothelial keratoplasty (12.41%) in the developing country.

Conclusion:

VED still contributes to majority of the donor tissue retrieval in India. The majority of the eye banks still utilize whole globe enucleation technique and store tissues in MK media. Trends from previous years showed a change towards HCRP, in-situ excision technique and preservation in the long-term storage media.

Unilateral acute hydrops in a child with bilateral microcornea and iridofundal coloboma

A 15-year-old female child with history of bilateral poor vision since childhood presented with sudden onset pain, photophobia, and diminution of vision OD for 10 days. Visual acuity was hand motion OD and 1/60 OS. Slit lamp examination revealed microcornea OU with multiple intrastromal fluid clefts OD and an irregular cornea and iridofundal coloboma OS. A clinical diagnosis of acute corneal hydrops OD was made, and the child was subjected to intraoperative optical coherence tomography guided intrastromal fluid drainage with air tamponade. The corneal edema resolved completely within 2 weeks resuming visual acuity to 3/60 allowing laser delimitation of fundal coloboma OD.

Microkeratome-assisted ultrathin Descemet's stripping automated endothelial keratoplasty: A randomized trial comparing single-pass versus double-pass technique

Purpose:

To compare the outcomes of two techniques, for preparation of microkeratome-assisted ultrathin grafts for Descemet's stripping automated endothelial keratoplasty (DSAEK).

Methods:

The study involved 20 eyes of 20 patients with pseudophakic bullous keratopathy, randomized into two groups. Group 1 eyes underwent microkeratome-assisted DSAEK using the single-pass technique for lenticule preparation, whereas group 2 eyes underwent microkeratome-assisted DSAEK using the double-pass technique. Patients were followed up till 6 months, postoperatively. Best-corrected visual acuity (BCVA) at final follow-up was considered as the primary outcome measure, whereas graft thickness (GT) contrast sensitivity and endothelial cell loss were considered as the secondary outcome measures. A P value of <0.05 was considered as statistically significant.

Results:

Baseline characteristics of two groups were comparable. The mean central GT was comparable in both groups at 6 months follow-up [group 1: 98 ± 24.46 μm, group 2: 129 ± 31.46 μm (P = 0.18)]. Both groups fared equally in terms of BCVA (P = 0.33). Contrast sensitivity was significantly better in group 1 eyes (P = 0.045). A statistically significant negative correlation was found between postoperative BCVA and postoperative GT (R = −0.728, P = 0.016). The percentage endothelial cell loss was slightly higher in group 2 eyes, although not statistically significant. Two eyes in group 2 experienced complications during lenticule preparation. None of the eye experienced any complication in the postoperative period.

Conclusion:

Both techniques provided grafts with comparable thickness and endothelial cell loss and were associated with comparable BCVA, at final follow-up visit. The contrast sensitivity was, however, better in eyes receiving grafts prepared with the single-pass technique.

Sinsky hook assisted roll preparation (SHARP): A modified technique for Descemet membrane endothelial keratoplasty donor preparation

Purpose

To describe a simple technique of sinsky hook assisted roll preparation (SHARP) for Descemet membrane endothelial keratoplasty (DMEK) donor preparation.

Methods

This experimental study was conducted at National Eye Bank, India with 40 optical grade human donor corneoscleral tissues found not suitable for surgery. 25 tissues were initially used to standardize the technique and remaining 15 for establishing the final technique. Donor corneal tissues were initially placed on a sterile Teflon block partially filled with tissue culture media. Initially, a partial thickness trephination was done followed by sinsky assisted 360° separation of the Descemet membrane (DM) from the underlying stroma (2 mm from the edge). The separation was further extended by 3–4 mm from the edge for 4–5 clock hours followed by bimanual peeling of the DM. This was followed by central 8 mm trephination. The primary outcome measures were a complete success (8 mm roll without peripheral edge tears) and partial success (8 mm roll with peripheral edge tears).

Results

DMEK roll was successfully peeled in 86.6% tissues (n = 13/15). Complete success was obtained in 66.6% tissues while partial success was obtained in 20% tissues. The median age of donor tissue was 45 years. The donor age of tissues, from which DMEK roll could not be obtained (2/12) was 15 days and 18 years.

Conclusion

SHARP is a simple technique of DMEK that does not require any sophisticated instruments.

Corneal Ectasia in Stevens-Johnson Syndrome: A Sequela of Chronic Disease

PURPOSE

To describe corneal ectasia in cases of chronic Stevens-Johnson syndrome (SJS).

DESIGN

Prospective observational study.

METHODS

Setting: Institutional.

PATIENTS

Fifteen consecutive cases of chronic SJS.

MAIN OUTCOME MEASURES

Best-corrected distance visual acuity (BCDVA), maximum corneal curvature (Kmax), anterior elevation, posterior elevation, thinnest pachymetry, and Sotozono severity score.

RESULTS

Thirty eyes of 15 patients were included. Corneal tomography using Scheimpflug technology (Pentacam-HR, Oculus GmbH) was performed. Nine eyes were excluded owing to poor-quality scans. The median age was 26 years. The median time from onset of disease to assessment for corneal ectasia was 7 years. The median BCDVA was 0.8 logMAR units at presentation. The median Sotozono severity score was 11. Corneal ectasia (Kmax > 48 diopters [D]) was noted in 76.2% of eyes. The mean Kmax was 58.37 ± 14.89 D. On Belin/Ambrosio enhanced ectasia display the median front and back elevation was 42 μm (10-176 μm) and 267 μm (15-2392 μm), respectively. The mean pachymetry was 377.76 ± 165.05 μm (133-448 μm). The point of maximum ectasia was peripheral in 57.1%, both central and peripheral in 19.1%, and central in 23.8% of eyes. On Spearman correlation analysis, deterioration in BCDVA (R = 0.759, P < .001) and increase in Kmax (R = 0.589, P = .005) was associated with higher disease severity (Sotozono grading).

CONCLUSION

Corneal ectasia is a common but often missed entity in cases of chronic SJS that may be a cause for poor visual acuity in these cases. All cases of SJS must be evaluated for corneal ectasia, especially when the visual acuity is disproportionate to the disease severity.