Journal of Cornea

Assessment of Factors Associated With Postoperative Pain After Photorefractive Keratectomy

Palochak, Cherilyn Mae A.; Santamaria, Joseph; Justin, Grant A.; More

Abstract

Purpose: 

To define the factors that affect patient’s self-assessed postoperative pain after photorefractive keratectomy (PRK).

Methods: 

Patients who underwent PRK in 2016 were evaluated. Anonymized data collected included patient gender, age, and season at the time of surgery, ablation depth, surgeon status (attending vs. resident), topical tetracaine use, and subjective pain scores at postoperative days (PODs) 1 and 7. Average pain scores and amount of pain medication taken were analyzed for each of the previously mentioned variables.

Results: 

Overall, 231 patients who underwent PRK were analyzed. The mean pain score and SD were 0.78 ± ۱.۸۷ on POD 1 and 0.03 ± ۰.۳۷ by POD 7. Patients who used topical tetracaine reported significantly higher pain on POD 1 and 7 compared with patients who did not use tetracaine (P < 0.001 and P = ۰.۰۳۸, respectively). No significant differences in pain scores were seen based on surgeon status, ablation depth, gender, and season. Patients who used topical tetracaine took a higher amount of oral pain medication (9.44 ± ۶.۰۱) compared with those who did not (7.02 ± ۴.۷۱) (P = ۰.۰۲۲).

Conclusions: 

Postoperative pain was significantly elevated in patients who used tetracaine on POD 1 and POD 7. These patients were also more likely to take oral pain medication than those who did not use topical tetracaine. Surgeon status, season, gender, and ablation depth showed no significant differences in subjective pain scores. Oral pain medication should be evaluated to assess efficacy and safety in inhibiting ocular pain after PRK.

Lower Corneal Haze and Aberrations in Descemet Membrane Endothelial Keratoplasty Versus Descemet Stripping Automated Endothelial Keratoplasty in Fellow Eyes for Fuchs Endothelial Corneal Dystrophy

Waldrop, William H.; Gillings, Matthew J.; Robertson, Danielle M.; More

Abstract

Purpose: 

To investigate the long-term corneal changes in patients with Fuchs endothelial corneal dystrophy contributing to superior postoperative visual outcomes after Descemet membrane endothelial keratoplasty (DMEK) compared with Descemet stripping automated endothelial keratoplasty (DSAEK).

Methods:

Using retrospective analysis, we evaluated 9 patients with Fuchs endothelial corneal dystrophy who underwent DSAEK in 1 eye and DMEK in the fellow eye. Patients were genotyped for the triplet repeat expansion in the TCF4 gene and imaged using optical coherence tomography, Scheimpflug imaging, and in vivo confocal microscopy through focusing.

Results: 

Eight of 9 subjects were genotyped, and all were found to harbor the triplet repeat expansion. The average time between endothelial keratoplasty and imaging was 76 ± ۲۲ and 37 ± ۹ months after DSAEK and DMEK, respectively. The mean best spectacle-corrected visual acuity (logMAR) was 0.04 ± ۰.۰۵ and 0.11 ± ۰.۰۳ in the DMEK eyes versus DSAEK eyes (P = ۰.۰۲), respectively. Posterior corneal higher order aberrations were less in the DMEK eyes compared with fellow DSAEK eyes (0.25 ± ۰.۰۶ and 0.66 ± ۰.۲۵, respectively, P ≤ ۰.۰۱). Using confocal microscopy through focusing, we found that the persistent anterior stromal haze was correlated between the right and left eyes (R = 0.73, P ≤ ۰.۰۵), but total stromal backscattering was higher for the DSAEK eyes (P ≤ ۰.۰۵).

Conclusions: 

DSAEK inherently results in higher total stromal backscattering (haze) compared with DMEK because of the addition of stromal tissue. Lower higher order aberrations of the posterior cornea and lower total stromal backscattering (haze) may both contribute to superior visual outcomes after DMEK compared with DSAEK.

Prospective Clinical Study of Keratoconus Progression in Patients Awaiting Corneal Cross-linking

Goh, Yi Wei; Gokul, Akilesh; Yadegarfar, Mohammad E.; More

Abstract

Purpose: 

Keratoconus progression should be treated with corneal cross-linking (CXL) in a timely manner. This study aimed to investigate patient factors associated with keratoconus progression between time of listing and at time of CXL.

Methods: 

Prospective observational study at a tertiary center. Ninety-six eyes of 96 patients with keratoconus. Demographic, clinical, and tomographic parameters were analyzed to determine the risk factors for keratoconus progression. Analyzed tomographic indices included steepest keratometry, average keratometry, cornea thinnest point, index of surface variance, index of vertical asymmetry, keratoconus index, center keratoconus index, index of height asymmetry, and index of height decentration.

Results: 

A total of 38 eyes (39.6%) were found to have keratoconus progression during an average waiting time of 153 ± ۱۰۱ days. There were significant differences in preoperative tomographic parameters such as index of surface variance (111.3 ± ۳۶.۶ vs. 88.3 ± ۳۱.۸; P = ۰.۰۰۲), index of vertical asymmetry (1.1 ± ۰.۴ vs. 0.9 ± ۰.۴; P = ۰.۰۰۵), keratoconus index (1.31 ± ۰.۱۲ vs. 1.22 ± ۰.۱۱; P < 0.001), and index of height decentration (0.16 ± ۰.۰۷ vs. 0.11 ± ۰.۰۶; P = ۰.۰۱۵) between eyes that progressed and those that remained stable. There were no significant differences in steepest keratometry, average keratometry, cornea thinnest point, and center keratoconus index. Multivariate analysis did not reveal age, presence of atopy/atopic keratoconjunctivitis, eye rubbing, or waiting time to be a significant risk factor for progression; however, Maori ethnicity was a risk factor (odds ratio = 3.89; P = ۰.۰۲).

Conclusions: 

A significant proportion of eyes were found to be progressing while waiting for CXL. A risk stratification score for patients awaiting CXL may reduce the risk of progression.

Efficacy of Amphotericin B in Corneal Preservation Media After Extended Frozen Storage

Huh, Doowon; Tran, Khoa D.; Straiko, Megan M. W.; More

Abstract

Purpose: 

To investigate the antimycotic activity of amphotericin B deoxycholate that has been previously frozen for 28 days before supplementation of Optisol-GS.

Methods: 

Triplicate Optisol-GS samples were inoculated with 106 colony-forming units (CFU) of Candida albicans. Each set of triplicate cultures was supplemented with 2.5 μg/mL of amphotericin B that was either freshly resuspended and never frozen, frozen overnight at −۲۰°C and thawed, or frozen at −۲۰°C for 4 weeks and thawed. The cultures were stored at 4°C, with aliquots taken at 0, 6, 24, and 72 hours for quantification. The efficacy of each preparation of amphotericin B in reducing C. albicans growth was assessed at these time points.

Results: 

Six hours after antifungal supplementation, there was a 1.33 log10 CFU reduction with freshly resuspended amphotericin B, compared with a 1.31 log10 reduction with amphotericin B that was frozen overnight (P = ۰.۲۰) and a 1.18 log10 reduction with amphotericin B that was frozen for 4 weeks (P = ۰.۰۵). After 72 hours, there was a 2.72 log10 CFU reduction with freshly resuspended amphotericin B, a 2.64 log10 CFU reduction with amphotericin B that was frozen overnight (P = ۰.۴۵), and a 2.18 log10 CFU reduction with amphotericin B that was frozen for 4 weeks (P = ۰.۰۵).

Conclusions: 

Previously frozen amphotericin B remains highly effective against C. albicans. Optisol-GS supplemented with 2.5 μg/mL amphotericin B that was frozen for 4 weeks at −۲۰°C resulted in >90% CFU reduction by 6 hours and >99% reduction by 72 hours.

Global Consensus on the Management of Limbal Stem Cell Deficiency

Deng, Sophie X.; Kruse, Friedrich; Gomes, José A. P.; More

Abstract

Purpose: 

In recent decades, the medical and surgical treatment of limbal stem cell deficiency (LSCD) has evolved significantly through the incorporation of innovative pharmacological strategies, surgical techniques, bioengineering, and cell therapy. With such a wide variety of options, there is a need to establish a global consensus on the preferred approaches for the medical and surgical treatment of LSCD.

Methods: 

An international LSCD Working Group was established by the Cornea Society in 2012 and divided into subcommittees. Four face-to-face meetings, frequent email discussions, and teleconferences were conducted since then to reach agreement on a strategic plan and methods after a comprehensive literature search. A writing group drafted the current study.

Results: 

A consensus in the medical and surgical management of LSCD was reached by the Working Group. Optimization of the ocular surface by eyelid and conjunctival reconstruction, antiinflammatory therapy, dry eye and meibomian gland dysfunction treatment, minimization of ocular surface toxicity from medications, topical medications that promote epithelialization, and use of a scleral lens is considered essential before surgical treatment of LSCD. Depending on the laterality, cause, and stage of LSCD, surgical strategies including conjunctival epitheliectomy, amniotic membrane transplantation, transplantation of limbal stem cells using different techniques and sources (allogeneic vs. autologous vs. ex vivo–cultivated), transplantation of oral mucosal epithelium, and keratoprosthesis can be performed as treatment. A stepwise flowchart for use in treatment decision-making was established.

Conclusions: 

This global consensus provides an up-to-date and comprehensive framework for the management of LSCD.

Descemet Membrane Detachment After Penetrating Keratoplasty for Keratoconus

Kit, Vivienne MBBS; Kriman, Jaime MD; Vasquez-Perez, Alfonso, FRCO; Muthusamy, Kirithika FRCOphth; Thaung, Caroline FRCOphth, FRCPath Tuft, Stephen MD, FRCO

Abstract

Purpose: 

To describe the risk factors, management, and outcome of delayed Descemet membrane (DM) detachment after penetrating keratoplasty (PK) for keratoconus.

Methods: 

We report 7 eyes from 6 cases and combine these data with 7 previous case reports identified by a search of PubMed.

Results:

DM detachment occurred at a median of 25 years (range, 7–۳۳ years) after PK. One individual had bilateral detachments. There was typically a mild ocular discomfort accompanied in some cases by a rapid onset of visual blur. Cases were often treated for allograft rejection before a DM detachment was suspected and confirmed by optical coherence tomography. Detachments were limited to the donor tissue in 11 eyes, but a DM break was identified at the time of onset in only 4 eyes. Thinning of the host corneal rim with ectasia was reported in 8 eyes (57%). In 3 eyes, the detachment resolved spontaneously, but in 2 eyes, a detachment was still present at 12 months. Gas tamponade to reattach the DM was performed in 9 eyes and was effective in 4 eyes. Five eyes underwent a repeat PK or endothelial keratoplasty. Histology showed fibroblastic proliferation on the stromal surface of the folded DM.

Conclusions: 

The cause for DM detachment many years after PK is unknown, although progressive thinning of the host cornea and secondary graft ectasia may be implicated. Gas tamponade can be effective, but a repeat keratoplasty might be necessary. DM detachment should be included in the differential diagnosis for late-onset corneal edema after PK.

Limbal Stem Cell Dysfunction in Ichthyosis Follicularis, Alopecia, and Photophobia Syndrome

Basilious, Alfred; Fung, Simon S. M.; Ali, Asim

Abstract

Purpose: 

To describe the presentation and management of limbal stem cell dysfunction in ichthyosis follicularis, alopecia, and photophobia (IFAP) syndrome.

Methods: 

A retrospective case report.

Results: 

A 6-day-old male infant was diagnosed with IFAP syndrome based on family history and a mutation detected in the MBTPS2 gene. Initial examination showed hyperkeratotic eyelids, madarosis, and lagophthalmos, but otherwise clear corneas. He developed bilateral central corneal epithelial defects spontaneously 6 months later, which were managed with aggressive lubrication, prophylactic antibiotics, and bilateral permanent lateral tarsorrhaphies at 7 months of age. During the procedure, the patient was noted to have bilateral limbal thickening, peripheral corneal pannus with underlying stromal scarring, and late fluorescein staining of the corneal surface. Anterior segment optical coherence tomography demonstrated a significantly abnormal and hyperreflective epithelial surface overlying a thinned corneal stroma, suggestive of limbal stem cell dysfunction. The corneal surface was maintained with lubrication and tarsorrhaphy and has remained stable since.

Conclusions: 

The progressive conjunctivalization, spontaneous epithelial defects, and anterior segment optical coherence tomography features are highly suggestive of limbal stem cell dysfunction in IFAP syndrome. Optimizing the ocular surface is of importance in the management of children with this rare disease.