Retrospective contralateral study comparing deep anterior lamellar keratoplasty with penetrating keratoplasty: a patient's perspective

Impacts of keratoconus on quality of life: a qualitative study

BACKGROUND/AIMS

To identify the domains of quality of life (QoL) in people with keratoconus.

METHODS

Semi structured in-depth in person and telephone interviews were conducted with participants diagnosed with keratoconus and recruited from the Sydney Eye Hospital, Sydney, Australia. Thematic analysis of interview content was conducted using inductive and deductive processes. Data was collected until thematic saturation was obtained.

RESULTS

33 patients with keratoconus with median age 37 (range 18 to 65) years and majority male (n = 25; 75.8%) were interviewed and a total of 2551 quotes coded. Thematic analysis resulted in 7 broad themes, Driving (199 references), Career (259 references), Symptoms (647 references), Enjoyment (149 references), Relationships (250 references), Financial (104 references) and Healthcare (881 references). Most references described a negative relationship between keratoconus and these 7 domains. The diverse QoL issues expressed included frustration with treatment effectiveness, fear of disease progression, inconvenience with contact lenses, forced career changes and job loss, cost of contact lenses, and feelings of isolation and discrimination. Themes and subthemes described a complex and varied relationship between keratoconus and QoL.

CONCLUSION

Severe quality of life impairment was experienced by keratoconus patients despite treatment. Keratoconus diminishes various aspects of individual's QoL. Therapies able to improve QoL are still needed for keratoconus.

Visual Outcomes of Microkeratome-Assisted Anterior Lamellar Keratoplasty in Keratoconus: 5-Year Results

Purpose

To report 5-year results of microkeratome-assisted anterior lamellar keratoplasty (MK-ALK) in cases of keratoconus.

Methods

Patients with advanced keratoconus and the thinnest corneal location 300 μ or more were recruited. A Carriazo–Barraquer microkeratome was used to remove a 200-μ cap from the recipient cornea, and to prepare a 300-μ anterior stromal graft from a donor cornea. A full-thickness crescentic incision was made in the posterior stromal recipient bed using a 6.5-mm suction trephine. The donor was sutured to the recipient bed using interrupted nylon sutures. The minimum follow-up was five years.

Results

Twelve eyes of 12 patients were included. The mean age was 26 ± 8 years. None of the patients required conversion to penetrating keratoplasty. Mean logMAR uncorrected and best spectacle-corrected visual acuity, respectively, improved from 1.56 ± 0.24 and 1.18 ± 0.32 preoperatively, to 0.63 ± 0.38 and 0.18 ± 0.12, five years after surgery (P=0.001for both). There was also a statistically significant reduction of mean manifest spherical equivalent, refractive cylinder, and mean keratometry readings. Posterior stromal striations occurred in all patients immediately after surgery but resolved after a maximum of 3 months. At five-years, anterior segment optical coherence tomography revealed a clear interface in all cases and a mean graft thickness of 328 ± 27 μ.

Conclusion

MK-ALK is a safe and effective procedure for advanced keratoconus. Where feasible, it may be the best choice for patients at high risk of poor outcomes with penetrating keratoplasty, such as young patients with atopic keratoconjunctivitis or Down's syndrome.

Component corneal surgery: An update

Several decades ago, penetrating keratoplasty was a challenge to corneal surgeons. Constant effort by the corneal surgeon to improve the outcomes as well as utilization of the available resources has led to a revolutionary change in the field of keratoplasty. All these efforts have led to the evolution of techniques that allow a corneal surgeon to disease-specific transplant of individual layers of corneal “so-called component corneal surgery” depending on the layer of cornea affected. This has led to an improvement in corneal graft survival as well as a better utilization of corneal tissues. This article reviews the currently available literature on component corneal surgeries and provides an update on the available techniques.

Treatment options for advanced keratoconus: A review

Traditionally, the mainstay of treatment for advanced keratoconus (KC) has been either penetrating or deep anterior lamellar keratoplasty (PK or DALK, respectively). The success of both operations, however, has been somewhat tempered by potential difficulties and complications, both intraoperatively and postoperatively. These include suture and wound-healing problems, progression of disease in the recipient rim, allograft reaction, and persistent irregular astigmatism. Taken together, these have been the inspiration for an ongoing search for less troublesome therapeutic alternatives. These include ultraviolet crosslinking and intracorneal ring segments, both of which were originally constrained in their indication exclusively to eyes with mild to moderate disease. More recently, Bowman layer transplantation has been introduced for reversing corneal ectasia in eyes with advanced KC, re-enabling comfortable contact lens wear and permitting PK and DALK to be postponed or avoided entirely. We offer a summary of the current and emerging treatment options for advanced KC, aiming to provide the corneal specialist useful information in selecting the optimal therapy for individual patients.

Descemetic and predescemetic DALK in keratoconus patients: a clinical and confocal perspective study

Purpose. To evaluate the clinical outcomes and in vivo confocal microscopy (IVCM) features of keratoconus patients who underwent deep anterior lamellar keratoplasty (DALK). Methods. DALK was performed using the big bubble technique in all the patients. If the bubble was not successful to bare the descemet membrane, a manual dissection layer-by layer was performed to expose a deep stromal plane close to the DM. The patients were divided in two groups depending on the intraoperative baring of the descemet membrane: predescemetic DALK (PD-DALK) and descemetic DALK (D-DALK) group. Results. One month after surgery the D-DALK patients show an increase of mean BCVA. In the PD-DALK group mean BCVA did not show significant improvement as compared to preoperative values. At 6 months after surgery mean BCVA was found to be similar in both groups. At 1 month IVCM the peak of reflectivity of the interface was lower in D-DALK group compared to PD-DALK. At 6 months the values of reflectivity were comparable. Conclusions. At 1 month D-DALK seems to lead to a minor interface reflectivity and to a better BCVA; these differences disappear after 6 months and the values of interface reflectivity and BCVA are comparable between D-DALK and PD-DALK.

Customised component corneal transplantation: a blessing for three patients

The existing acute shortage of good quality donor corneas in a developing country like India, prompted us to attempt customised component corneal transplantation. Using this surgical strategy, one corneoscleral button was used for three recipients. Anterior and posterior lamellar discs were used for anterior lamellar keratoplasty and Descemet's stripping endothelial keratoplasty in patients with superficial corneal scar and pseudophakic bullous keratopathy, respectively. From the remnant peripheral corneoscleral rim, a patch graft was taken and used for a case of perforated corneal ulcer. Postoperatively, the two earlier mentioned cases achieved visual acuities of 20/30 and 20/60, respectively, whereas the latter mentioned patient with the patch graft achieved good tectonic stability. This case report highlights the optimal utilisation of a corneoscleral button by customising it for three recipients. Moreover, a patch graft has been introduced in the armamentarium of customised component corneal transplantation for the first time.

Deep anterior lamellar keratoplasty with a manual spatula: anatomical and functional results

Objective:

Evaluate the anatomical, refractive, and functional results of an innovative technique of deep anterior lamellar keratoplasty with a manual spatula.

Materials and Methods:

We evaluated the results and examinations of 16 eyes from 14 patients who underwent deep anterior lamellar keratoplasty using the technique described by Ferrara. Residual bed thickness after keratoplasty was evaluated postoperatively using Visante. The measurement was performed using a technique similar to that used to measure flap thickness after laser in situ keratomileusis refractive surgery. The measurements were performed at the center of the cornea in an area comprising the central 3-mm in the 45° and 135° meridians.

Results:

Best-corrected visual acuity was 0.34 ± 0.18 LogMar (0.09 to 0.60 LogMar), the spherical equivalent was -4.31 ± 3.38 D (+0.25 to -9.50 diopters), and keratometry was 45.75 ± 2.77 D (41.11 to 52.48 diopters) postoperatively. Corneal astigmatism was 3.19 ± 2.78 D (0.18 to 11.81 diopters). Residual stromal bed thickness measured by optical coherence tomography showed values of 67.1 ± 24.3 μm (30 to 109 μm). The statistical correlation by Spearman's test between the best-corrected visual acuity and the residual stromal bed thickness was 0.11 (P = 0.67).

Conclusion:

Deep anterior lamellar keratoplasty, in which manual dissection was performed using an instrument similar to that used to implant corneal rings, provided good visual and anatomical results.

Lamellar keratoplasty: a literature review

The concept of lamellar keratoplasty (LK) is not new. However, newer forms of lamellar keratoplasty techniques have emerged in the last decade or so revolving around the concept of targeted replacement of diseased corneal layers. These include anterior lamellar keratoplasty (ALK) techniques that aim to selectively replace diseased corneal stroma and endothelial keratoplasty techniques aiming to replaced damaged endothelium in endothelial disorders. Recent improvements in surgical instruments and introduction of new techniques as well as inherent advantages such as preservation of globe integrity and decreased graft rejection have resulted in the reintroduction of LK as an acceptable alternative to conventional PK. In this review, indications, benefits, limitations, and outcomes of various anterior and posterior lamellar keratoplasty techniques are discussed.