Effect of Previous Crosslinking on Intraoperative and Postoperative Outcomes and Complication Rates of Big-Bubble Deep Anterior Lamellar Keratoplasty for Keratoconus: A Comparative Study.

PURPOSE: To compare surgical outcomes and intraoperative and postoperative complications of big-bubble deep anterior lamellar keratoplasty (DALK) in patients with and without a history of previous corneal collagen crosslinking (CXL) for keratoconus. METHODS: Patients with keratoconus who underwent DALK surgery with big-bubble technique between January 2013 and January 2018 were retrospectively reviewed. Operative findings, intraoperative and postoperative complications, and visual and refractive outcomes were recorded. Patients were divided into 2 groups: with previous CXL (CXL-DALK group: 27 eyes) and without previous CXL (DALK group: 50 eyes). All parameters were compared between groups. RESULTS: Big bubble was successfully achieved in 24 eyes (88.9%) in the CXL-DALK group and in 45 eyes (90.0%) in the DALK group (P = 0.87). Type 1 bubble was obtained in 22 eyes (91.7%) in the CXL-DALK group and in 42 eyes (93.3%) in the DALK group (P = 0.79). Intraoperative microperforation occurred in 3 eyes (11.1%) in the CXL-DALK group and in 5 eyes (10.0%) in the DALK group (P = 1). Visual and refractive outcomes were similar between groups. The mean endothelial cell loss rates were 5.7% ± 2.3 at 1 year and 10.2 ± 3.1 at 2 years in the CXL-DALK group and 6.4% ± 4.7 at 1 year and 10.9% ± 5.4 at 2 years in the DALK group. Postoperatively, persistent epithelial defect was the most common complication in both groups, and postoperative complication rates were similar between groups. CONCLUSIONS: Our results have shown that previous CXL treatment does not influence the success of bubble formation and does not increase intraoperative or postoperative complication rates of DALK surgery for keratoconus. The improvement in visual acuity and refractive errors and endothelial cell loss rates were similar between CXL treated and untreated eyes after 2 years of follow-up.

Deep anterior lamellar keratoplasty in eyes previously treated with collagen crosslinking for keratoconus: 3-year results.

PURPOSE: To evaluate the 3-year results of deep anterior lamellar keratoplasty (DALK) using the big-bubble technique in keratoconus patients with previous corneal collagen crosslinking (CXL) treatment. METHODS: Twenty eyes of 20 keratoconus patients who underwent DALK surgery using the big-bubble technique after CXL treatment between January 2011 and September 2015 were retrospectively reviewed. All patients completed 3 years follow-up. Intraoperative and postoperative complications were recorded. Uncorrected visual acuity (UCVA), best spectacle corrected visual acuity (BSCVA), maximum keratometry, keratometric astigmatism and endothelial cell density (ECD) were analysed. RESULTS: The mean interval between CXL and DALK surgery was 47.5 ± 24.0 months (mean ± SD). DALK was completed in all eyes. Big-bubble was successfully achieved in 16 eyes (80%), and manual dissection was performed in four eyes (20%). Microperforation occurred in three eyes (15%). Postoperatively, persistent epithelial defect occurred in three eyes (15%). The mean UCVA and mean BSCVA values were significantly improved preoperatively to all postoperative visits (p < 0.001). UCVA was 20/100 or lower in all eyes preoperatively and 20/100 or better in 18 eyes (80%) at 3 years; BSCVA was 20/40 or better in all eyes (100%) and 20/20 or better in three eyes (15%), and keratometric astigmatism was lower than 4 dioptres in 14 eyes (70%) at 3 years. The mean ECD loss was 6.3 ± 4.4% at 1 year, 9.0 ± 6.3% at 2 years and 11.2 ± 7.4% at 3 years. CONCLUSION: Previous CXL treatment in keratoconus patients did not cause a negative impact on the visual, refractive and surgical outcomes of DALK surgery using the big-bubble technique. DALK surgery seems to be a safe and effective surgical approach in these patients.

Characteristics of pediatric and adult cases with open globe injury and factors affecting visual outcomes: A retrospective analysis of 294 cases from Turkey.

BACKGROUND: This study aimed to evaluate 1-year follow-up results of cases that were diagnosed with open globe injury (OGI), to compare trauma-related characteristics between pediatric and adult cases, and to determine risk factors for a poor final visual acuity. METHODS: This study enrolled 294 cases that met the OGI definition and were followed up for at least 1 year. Demographic and clinical features regarding ocular trauma were recorded. The cases were divided into two groups according to age: pediatric (≤16 years) and adult (>16 years) groups. RESULTS: Children were exposed to accidents that led to OGI mostly at home, whereas adults were exposed to such accidents mostly in the office. Penetrating injuries were more common in children than in adults, and injuries most commonly occurred owing to spiky objects. Zone I injuries were most frequent in both children and adults. The frequency of high-grade injuries increased with age. Foreign body injuries and multiple surgeries were more common in adults than in children. There was no difference between the two age groups based on ocular trauma score (OTS) and visual acuity. OTS predicted the need for multiple surgeries. In the adult group, age, multiple surgeries, and initial visual acuity were significant risk factors for the final visual acuity that was achieved. CONCLUSION: OGI causes and risk factors for poor final visual outcomes differ in adults and children. The knowledge of these differences is crucial for taking adequate preventive measures and decreasing morbidity.

Traumatic wound dehiscence after deep anterior lamellar keratoplasty.

PURPOSE: To analyze the outcomes of traumatic wound dehiscence after deep anterior lamellar keratoplasty (DALK). DESIGN: Retrospective and interventional case series. SETTING: Single hospital. PATIENTS: A total of 338 consecutive cases were reviewed. Eleven eyes that had wound dehiscence related to ocular trauma were included. MAIN OUTCOME MEASURES: Incidence and causes, best-corrected visual acuity (BCVA), and endothelial cell density were evaluated. Complications and secondary surgeries were recorded. RESULTS: Seven patients were male (63.6%) and 4 patients were female (36.4%), with a mean age of 30.6 years (range, 24-40 years). The incidence of wound dehiscence was 3.2% (11/338). The mean interval between the initial DALK procedure and wound dehiscence was 9.45 months (range, 2-16 months). The mean follow-up time was 6 years. The most common trauma was a fist blow injury (36.3%). Descemet membrane perforation was observed in 8 eyes (72.7%); lens damage and vitreous prolapse occurred in 2 eyes (18.1%). The final BCVA was 0.51 and was maintained in 4 eyes (36.3%). At the final visit, 10 grafts (90.9%) were clear. The mean endothelial cell loss was 55.8% between before DALK and last visit. CONCLUSION: Although the intact Descemet membrane protects against dehiscing traumas after DALK, a relative weakness at the graft-host junction tends to persist and a severe deforming force may result in graft dehiscence. This case series indicates that despite the fact that the visual results following the repair are acceptable, corneal endothelium seems to be subjected to severe damage, which puts graft survival chances at risk in the long term.

Deep anterior lamellar keratoplasty versus penetrating keratoplasty for macular corneal dystrophy: a randomized trial.

PURPOSE: To compare outcomes of big-bubble deep anterior lamellar keratoplasty (DALK) and penetrating keratoplasty (PK) for macular corneal dystrophy. DESIGN: Prospective, randomized, interventional case series. METHODS: setting: Single hospital. patients: Eighty-two eyes of 54 patients requiring keratoplasty for the treatment of macular corneal dystrophy without endothelial involvement were included. main outcome measures: Operative complications, uncorrected visual acuity, best-corrected visual acuity, contrast sensitivity function, higher-order aberrations, and endothelial cell density were evaluated. RESULTS: The DALK and PK group consisted of 35 and 41 eyes, respectively. Best-corrected visual acuity after surgery was 20/40 or better 68.5% and 70.7% of the eyes in the DALK and PK groups, respectively (P > .05). No statistically significant differences between groups were found in contrast sensitivity function with and without glare for any spatial frequency (P > .05). Significantly higher levels of higher-order aberrations were found in the DALK group (P < .01). In both groups, a progressive and statistically significant reduction in endothelial cell density was found (P < .01). At the last follow-up, the mean endothelial cell loss was 18.1% and 26.9% in DALK and PK groups, respectively (P = .03). Graft rejection episodes were seen in 5 eyes (12.1%) in the PK group, and regrafting was necessary in 3 eyes (7.3%). Recurrence of the disease was documented in 5.7% and 4.8% of the eyes in the DALK and PK groups, respectively. CONCLUSIONS: Deep anterior lamellar keratoplasty with the big-bubble technique provided comparable visual and optical results as PK and resulted in less endothelial damage, as well as eliminating endothelial rejection in macular corneal dystrophy. Deep anterior lamellar keratoplasty surgery is a viable option for macular corneal dystrophy without endothelial involvement.

Toric implantable collamer lens for moderate to high myopic astigmatism: 3-year follow-up.

BACKGROUND: To evaluate the 3-year clinical outcomes after toric implantable collamer lens (ICL) implantation for the management of moderate to high myopic astigmatism. METHODS: Thirty-four eyes of 20 patients who underwent toric ICL implantation were reviewed. All eyes completed 3-year follow-up. Uncorrected (UDVA) and corrected (CDVA) distance LogMAR visual acuities, refraction, endothelial cell density (ECD), and surgical complications were evaluated. Vectorial analysis of astigmatic correction was also done. RESULTS: A significant improvement in UDVA, CDVA, manifest spherical and cylindrical refraction was observed at 1 week and remained stable after 3 years. Twenty-six eyes (76.5%) gained lines of CDVA, and two eyes (5.9%) showed a loss of 1 line of CDVA. The spherical equivalent (SE) was within ±0.50 D of emmetropia in 18 eyes (52.9%) and within ±1.00 D in 28 eyes (82.4%). Differences between target-induced astigmatism (TIA) and surgically-induced astigmatism (SIA) were statistically significant (p < 0.01), and a trend to undercorrection of the refractive astigmatism was present after 3 years. The magnitude of flattening effect (FE) was found to be significantly lower than the magnitude of TIA (p < 0.01). The magnitude of the torque vector was always positive, with a value below 0.50 D in all cases. No vision-threatening complications were observed during the follow-up. CONCLUSION: Toric ICL implantation is an effective and safe surgical option that provides a relatively predictable and stable refractive correction of myopic astigmatism. Further improvements are needed to minimize the degree of undercorrection.

Penetrating keratoplasty versus deep anterior lamellar keratoplasty: comparison of optical and visual quality outcomes.

PURPOSE: To evaluate and compare visual and optical performance outcomes by means of analysis of the contrast sensitivity function (CSF) and ocular higher order aberrations (HOA) in patients with keratoconus who had deep anterior lamellar keratoplasty (DALK) or penetrating keratoplasty (PK). METHODS: In this prospective, randomised case series, 174 eyes of 140 consecutive patients with moderate to advanced keratoconus were included. The big-bubble technique was attempted to perform DALK. Intraoperative and postoperative complications, uncorrected visual acuity, best spectacle-corrected visual acuity (BSCVA), refraction, topographic astigmatism, CSF and ocular HOA were evaluated. RESULTS: The DALK and PK groups consisted of 99 and 75 eyes, respectively. Postoperative BSCVA was 20/40 or better in 64 eyes (85%) in the PK group and and 82 eyes (83%) in the DALK group (p>0.05). The mean spherical equivalent and maximum keratometry were -1.50 (-6.25 to +4.75) and 46.85 (40.60 to 56.00) in the PK group and -2.25 (-8.75 to +4.00) and 46.90 (40.60 to 53.60) in the DALK group, respectively. The differences were not statistically significant (p=0.08 and p=0.66, respectively). No significant differences in photopic contrast sensitivity were found for each of the spatial frequencies (p>0.05 for all). However, mesopic contrast sensitivity for three cycles/degree was significantly higher in the DALK group (p=0.01). No significant differences between groups were detected for any of the aberrometric parameters (p>0.05). CONCLUSIONS: DALK is an alternative treatment option in eyes with moderate to advanced keratoconus, providing comparable results to PK in terms of visual acuity, refraction, CSF and HOA.

Elevation changes of central posterior corneal surface after intracorneal ring segment implantation in keratoconus.

PURPOSE: To compare changes that occur at the posterior corneal surface after the implantation of intracorneal ring segments (ICRSs) using either mechanical or femtosecond laser-assisted procedures and to correlate these changes with the visual outcome achieved. METHODS: Retrospective, nonrandomized, and interventional case series including 223 consecutive eyes of 186 patients with keratoconus ranging in age from 16 to 39 years that were implanted with ring segments (KeraRing; Mediphacos) at Kartal Training and Research Hospital, Istanbul, Turkey. Two groups were created according to the surgical technique used: mechanical group (168 eyes) and femtosecond group (55 eyes). Visual and refractive outcomes and corneal elevation changes were evaluated during a 24-month follow-up. Correlations between visual and posterior elevation changes were evaluated. RESULTS: The posterior corneal surface could not be analyzed with accuracy for diameters larger than the diameter of the ICRS implant. A statistically significant reduction of maximum elevation for both the corneal surfaces was observed at 1 month after the surgery (P < 0.01), with additional reductions at 3 and 6 months (P ≤ 0.03). In addition, the posterior best-fit sphere was flattened significantly at 1 month after the surgery in both the groups, with additional flattening at 3 months (P ≤ 0.03). No significant differences between groups in posterior corneal elevation parameters were found at any time point of the follow-up (P ≥ 0.14). Moderate and significant correlations of the postoperative visual outcome with the change in posterior best-fit sphere were found only in the femtosecond group. CONCLUSIONS: A central corneal flattening of the posterior corneal surface occurs after ring segment implantation in keratoconus.

Comparison of deep anterior lamellar keratoplasty and intrastromal corneal ring segment implantation in advanced keratoconus.

PURPOSE: To compare the visual and refractive results in eyes with advanced keratoconus having deep anterior lamellar keratoplasty (DALK) with those having intrastromal corneal ring segment (ICRS) implantation. SETTING: Dr. Lütfi Kirdar Kartal Training and Research Hospital, Istanbul, Turkey. DESIGN: Comparative case series. METHODS: Records of advanced keratoconus patients with a clear central cornea and contact lens intolerance who had DALK or ICRS implantation were reviewed. Preoperatively and after 24 months, the uncorrected (UDVA) and corrected (CDVA) distance visual acuities, refraction, and Orbscan II keratometry (K) readings in the 2 groups were comparable. RESULTS: The DALK group comprised 36 eyes and the ICRS group, 30 eyes. Both groups had a statistically significant increase in UDVA and CDVA from preoperatively to 24 months postoperatively (P<.001). The DALK group had a statistically significantly greater improvement in UDVA and CDVA than the ICRS group 24 months postoperatively (P<.001). The improvement in spherical equivalent (SE) refractive error, manifest sphere, and manifest cylinder was statistically significant in both groups (P<.001). The mean reduction in SE and manifest cylinder were significantly greater in the DALK group (P<.05). The postoperative reduction in the maximum and minimum K values was statistically significant in both groups (P<.001); the mean reduction in K values was significantly greater in the DALK group (P<.001). CONCLUSION: Although DALK provided greater improvement in visual acuity and refractive errors in advanced keratoconus cases, ICRS implantation may be an alternative treatment with satisfactory outcomes and less visual impact.

Foldable iris-fixated phakic intraocular lens implantation for the correction of myopia: two years of follow-up.

PURPOSE: To evaluate the safety, efficacy and potential risks of Artiflex foldable iris-fixated phakic intraocular lens (pIOL) implantation for the management of myopia. MATERIALS AND METHODS: Seventy-eight eyes of 40 consecutive patients with a mean spherical refraction of -11.70 ± 3.77 diopters (D; range -5.50 to -17.5 D) were included in this prospective, noncomparative, interventional case series. Main parameters assessed were uncorrected visual acuity (UCVA), best-spectacle corrected visual acuity (BSCVA), corneal topography (Orbscan II, BauchandLomb, Rochester, NY, USA), manifest and cycloplegic refractive errors, endothelial cell density (ECD) and applanation tonometry. RESULTS: After 2 years, BSCVA was 20/40 or better in 82% of the eyes and UCVA was 20/40 or better in 84% of the eyes. After 1 month, 1 year, and 2 years, 51.3% (37 of 72 eyes), 58.9% (46 of 78 eyes) and 76.0% (38 of 50 eyes) of eyes gained 1 line or more of BSCVA, respectively. Compared to preoperative values, the mean endothelial cell loss was 2.6% at 1 month, 4.9% at 1 year and 7.4% at 2 years. Pigmented or non-pigmented precipitates were observed in 17 eyes (21.7%) which were treated with topical corticosteroids. At the second postoperative year, pigmented precipitates persisted in nine eyes. However, this was not associated with a loss of BSCVA. CONCLUSION: The implantation of Artiflex pIOL is an effective surgical option for the management of high myopia. The most common complication observed within 2 years of follow-up was accumulation of pigmented precipitates with no effect on the final BSCVA.

Corneal endothelium after deep anterior lamellar keratoplasty and penetrating keratoplasty for keratoconus: a four-year comparative study.

PURPOSE: To compare the status of corneal endothelium and central corneal thickness within the first four postoperative years after deep anterior lamellar keratoplasty (DALK) and penetrating keratoplasty (PK) in patients with keratoconus. MATERIALS AND METHODS: Thirty-nine eyes (Group A) which had PK and 44 eyes (Group B) which had DALK for the treatment of keratoconus were included in this retrospective study. The endothelial cell density (ECD), the mean endothelial cell area and the coefficient of variation of cell area were assessed with a non-contact specular microscope, and the central corneal thickness (CCT) was measured with an ultrasound pachymeter. RESULTS: Mean ECD loss rate at two years was 36.24% in Group A and 18.12% in Group B (P<0.001). Mean ECD loss rate at four years was 47.82% in Group A and 21.62% in Group B (P<0.001). Mean annual ECD loss rate was calculated 14.12% per year in Group A and 5.78% per year in Group B. In the PK group, increase in mean CCT was 15.60% in two years and 15.03% in four years, while in the DALK group, mean CCT increased by 8.05% in two years and 9.31% in four years. CONCLUSIONS: As the majority of ectatic disorders such as keratoconus occur in young people, long-term endothelial cell survival following treatment with keratoplasty is essential for the long-term visual ability. Our finding that corneal endothelial cell loss in the DALK group occurs at a slower rate than in the PK group suggests DALK as a safer alternative to PK in these selected patients.

Penetrating keratoplasty in congenital hereditary endothelial dystrophy.

PURPOSE: To compare the results of penetrating keratoplasty (PK) in a series of congenital hereditary endothelial dystrophy (CHED) patients operated at amblyogenic years and at later ages. METHODS: Records of 65 eyes of 35 CHED patients who underwent PK were reviewed retrospectively. Visual results and graft clarity rates were compared between patients operated after (group 1) and before (group 2) 12 years of age. Results were also compared between eyes with and without nystagmus. RESULTS: Group 1 consisted of 47 eyes (24 patients), whereas group 2 consisted of 18 eyes (11 patients). Thirteen patients (54%) in group 1 and 10 patients (91%) in group 2 had nystagmus. Mean ages at surgery were 26.4 and 7.6 years in group 1 and group 2, respectively. Mean follow-up period was 101.0 months in group 1 and 59.7 months in group 2. Group 1 cases had better graft clarity rates than group 2 cases (P = 0.023). Postoperative best-corrected visual acuities (BCVAs) were 20/80 or better in 39 eyes of group 1 (83%) and in 5 eyes of group 2 (28%). Visual outcomes were found significantly better in group 1 cases (P < 0.001). In group 1, 76% of eyes with nystagmus and 91% of eyes without nystagmus had BCVAs of 20/80 or better. In group 1, both preoperative and postoperative BCVAs were found significantly better in eyes without nystagmus (P < 0.001 and P = 0.002, respectively). CONCLUSIONS: Delayed keratoplasty seems to offer better graft outcomes and visual prognosis to CHED patients, even in the presence of nystagmus.

Changes in central macular thickness after uncomplicated corneal transplantation for keratoconus: penetrating keratoplasty versus deep anterior lamellar keratoplasty.

PURPOSE: The aim of this study was to assess changes in macular thickness by means of optical coherence tomography after penetrating keratoplasty (PKP) and deep anterior lamellar keratoplasty (DALK) for keratoconus. METHODS: This prospective study comprised 60 eyes of 60 patients who had keratoplasty for the treatment of keratoconus. Eyes were divided into 2 groups according to the keratoplastic technique applied: PKP group and DALK group. Measurements of central macular thickness were performed preoperatively and 1, 3, and 6 months after surgery. RESULTS: The final analysis included 33 eyes in the PKP group and 24 eyes in the DALK group. In the PKP group, the central macula was found to be 6.5%, 6.3%, and 4.5% thicker in the first, third, and sixth month, respectively. Similarly, the central macula was 5.6%, 5.4%, and 2.9% thicker at months 1, 3, and 6 in the DALK group. The 2 groups did not differ significantly in terms of macular thickening. The percentage of eyes showing more than 10% increase in the macular region at any time during the follow-up period was 43.2% in the PKP group and 50.0% in the DALK group (P = 0.614). The percentage of eyes found to have a central macular thickness more than 250 µm at any time during the follow-up period was 10.8% in the PKP group and 18.2% in the DALK group (P = 0.424). CONCLUSIONS: The study showed that DALK, although it is a closed-system technique, has a similar impact on the macula compared with PKP.

Comparison of astigmatic keratotomy results in deep anterior lamellar keratoplasty and penetrating keratoplasty in keratoconus.

PURPOSE: To compare astigmatic keratotomy (AK) outcomes in high astigmatism after deep anterior lamellar keratoplasty (DALK) and after penetrating keratoplasty (PK) in keratoconus patients. DESIGN: Prospective, comparative, interventional case series. METHODS: This study comprised 20 eyes that underwent DALK and 24 eyes that underwent PK. After suture removal, all eyes had more than 5 diopters (D) of astigmatism and underwent standard manual 1-pair, 90-degree, and 90% corneal thickness AK incisions. The main outcome measures included preoperative and postoperative manifest refraction, uncorrected visual acuity, best spectacle-corrected visual acuity, surgically induced astigmatism, Orbscan II (Bausch & Lomb) corneal topography results, keratometric astigmatism, and complications. RESULTS: All eyes completed 6 months of follow-up. The overcorrection rate was 35% and 41.6% in the DALK and PK groups, respectively (P=.75). At 6 months after AK, logarithm of the minimal angle of resolution uncorrected visual acuity improved from 0.88 ± 0.20 to 0.54 ± 0.26 and from 1.0 ± 0.34 to 0.53 ± 0.26 in the DALK and PK groups, respectively (P=.01 to P<.01). Best spectacle-corrected visual acuity improved from 0.16 ± 0.09 to 0.13 ± 0.08 and from 0.16 ± 0.12 to 0.11 ± 0.08 in the DALK and PK groups, respectively (P=.13 to P=.01). The mean refractive cylinder was decreased 2.74 ± 1.44 D in the DALK group and 3.18 ± 2.96 D in the PK group (P=.35). Surgically induced astigmatism was 6.10 ± 3.27 D in the DALK group and 7.15 ± 2.98 D in the PK group (P=.36). CONCLUSIONS: The manual AK for the treatment of postkeratoplasty astigmatism after DALK and PK in keratoconus patients is a safe and effective surgical procedure, allowing similar refractive cylinder reduction and improvement in uncorrected visual acuity and best spectacle-corrected visual acuity.

Long-term results of deep anterior lamellar keratoplasty for the treatment of keratoconus.

PURPOSE: To evaluate the long-term endothelial cell density (ECD) changes and visual and refractive outcomes after deep anterior lamellar keratoplasty (DALK) using the big-bubble technique in eyes with keratoconus. DESIGN: Retrospective interventional case series study. METHODS: setting: Single hospital. patients: Two hundred forty-one eyes of 214 patients who underwent DALK for moderate to advanced keratoconus. main outcome measures: Intraoperative and postoperative complications, postoperative uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), spherical equivalent refraction, topographic astigmatism, and ECD. RESULTS: Two hundred thirty-four procedures (97%) were completed as DALK. Big bubble was successfully achieved in 193 eyes (82.4%). In 7 eyes (3%), the procedure was converted to penetrating keratoplasty because of Descemet membrane macroperforations. Microperforations occurred in 18 eyes (7.5%). The mean follow-up time was 50.5 ± 22.2 months (range 24 to 96 months). UCVA was lower than 20/100 in all eyes preoperatively and better than 20/100 in 191 eyes (81.6%) postoperatively. BSCVA was 20/40 or better in 187 eyes (79.9%) and 20/20 or better in 38 eyes (16.2%). The mean (± SD) preoperative ECD that was possible in 166 eyes was 2797 ± 561 cells/mm(2). Mean (± SD) endothelial cell loss was 8.1% ± 4.6% at 1 year, 10.5% ± 5.7% at 2 years, 15.1% ± 14.8% at 6 years, and 22.5% ± 15.9% at 8 years. Stromal graft rejection episodes occurred in 4 eyes, which resolved with appropriate therapy. CONCLUSIONS: Deep anterior lamellar keratoplasty that uses the big-bubble technique is effective in patients with keratoconus. Long-term endothelial cell loss was moderate and lower than penetrating keratoplasty grafts.

Intraocular lens exchange through a 3.2-mm corneal incision for opacified intraocular lenses.

AIM: The aim was to evaluate visual and refractive results and complications of intraocular lens (IOL) exchange through a 3.2 mm corneal incision for opacified IOLs. MATERIALS AND METHODS: This retrospective study comprised 33 eyes of 32 patients with IOL opacification requiring an IOL exchange between July 2003 and March 2007. Exchange surgery was performed through a 3.2-mm temporal clear corneal incision followed by implantation of a new foldable hydrophobic IOL. Uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), topographical astigmatism, and refractive cylinder were evaluated. Surgically induced astigmatism (SIA) was calculated and complications were recorded. RESULTS: Opacification was observed in 25 eyes (76%) with Aqua-Sense, 3 eyes (9%) with Hydroview, 3 eyes (9%) with MemoryLens IOLs, and 2 eyes (6%) with DgR. The mean follow-up period was 36.54 months. An uneventful IOL exchange was achieved in 18 eyes (55%). Zonular dehiscence occurred in 9 eyes (27%), and posterior capsule tear developed in 4 eyes (12%). The mean preoperative BSCVA (mean ± standard deviation, decimal scale) was 0.13 ± 0.08 (mean: 20/150, range 20/2000 to 20/60) and improved to 0.63 ± 0.18 (mean: 20/32, range 20/60 to 20/20, P < 0.001). The mean SIA was 0.70 D. Seven eyes (21%) had 0.5 D or lower SIA. CONCLUSION: IOL exchange is a technically challenging procedure with potential risks of reversing the advantages of a prior small-incision cataract surgery. The use of a small corneal incision for IOL exchange could preserve the advantages of modern phacoemulsification surgery with acceptable SIA related to the procedure.

Comparison of mechanical and femtosecond laser tunnel creation for intrastromal corneal ring segment implantation in keratoconus: prospective randomized clinical trial.

PURPOSE: To compare the outcomes of mechanical and femtosecond laser-assisted tunnel creation for intrastromal corneal ring segment (ICRS) implantation in eyes with keratoconus. SETTING: Kartal Training and Research Hospital, Istanbul, Turkey. METHODS: In this prospective study, consecutive eyes with keratoconus were randomly assigned to have ICRS tunnel creation with a mechanical device or a femtosecond laser. Keraring ICRS with a 5.0 mm diameter and 160-degree arc length were implanted in all cases. The uncorrected (UDVA) and corrected (CDVA) distance visual acuities, refraction, and keratometry (K) readings were measured preoperatively and 1 year postoperatively, and the data in the mechanical group and the femtosecond group were compared statistically. RESULTS: One year postoperatively, there was significant improvement in UDVA, CDVA, K readings, spherical equivalent (SE), and manifest sphere and cylinder in both groups (P<.05). The UDVA improved by 2.4 lines in the mechanical group and 2.0 lines in the femtosecond group and the CDVA by 3.3 lines and 2.7 lines, respectively; the mean reduction in maximum keratometry was 4.50 diopters (D) and 4.70 D, respectively, and the mean reduction in SE, 3.18 D and 3.09 D, respectively. There were no statistically significant differences between the 2 groups in visual or refractive results (P>.05). Anterior corneal perforation, superficial segment placement, and segment extrusion occurred in 1 eye each in the mechanical group. Segment migration occurred in 1 eye in the femtosecond group. CONCLUSION: Despite intraoperative complications in the mechanical group, the visual and refractive outcomes were similar to those in the femtosecond group.

Implantation of new intracorneal ring segments after segment explantation for unsuccessful outcomes in eyes with keratoconus.

PURPOSE: To evaluate the visual, refractive, and corneal aberrometric outcomes in eyes with keratoconus that had implantation of new intracorneal ring segment (ICRS) after previous segment explantation for an unsuccessful outcome. SETTING: Vissum Corporation, Alicante, Spain. METHODS: This retrospective nonrandomized case series included consecutive eyes of patients ranging in age from 18 to 64 years. All cases had an initial diagnosis of keratoconus and had ICRS implantation to manage corneal irregularity. In all cases, the initial ICRS were explanted because of an unsuccessful outcome (eg, segment extrusion, poor visual outcomes) and a new ICRS combination was implanted subsequently. A complete ophthalmic examination was performed in all eyes before and 1 month after initial ICRS implantation, before ICRS explantation, and 1 month and 6 months after implantation of the new ICRS. RESULTS: Twenty-one eyes (21 patients) were evaluated. There was a significant improvement in uncorrected distance visual acuity (P = .03) and thus a significant improvement in manifest refraction 1 month after implantation of the new ICRS (P/=.07). CONCLUSION: Significant visual and refractive improvements were achieved by implanting a new ICRS combination after previous unsuccessful ICRS implantation. FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned.

A single 210-degree arc length intrastromal corneal ring implantation for the management of pellucid marginal corneal degeneration.

PURPOSE: To determine the visual and refractive outcomes of 210-degree arc length intrastromal corneal ring segment (ICRS) implantation in eyes with pellucid marginal corneal degeneration (PMCD). DESIGN: Retrospective, consecutive case series. METHODS: Sixteen consecutive eyes of 10 patients who underwent a single 210-degree ICRS implantation by femtosecond laser for the management of PMCD and completed at least 1 year follow-up were included. A complete ophthalmic examination was performed preoperatively and postoperatively, including uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), manifest spherical and cylindrical refractions, spherical equivalent, and keratometric readings. RESULTS: The mean follow-up period was 30.7 months (range 12 to 36 months). No intraoperative complication was observed. White deposits around the segments were noted in 2 of 16 eyes (12.5%) at the first postoperative year. The mean UCVA showed significant improvement, from 1.69 +/- 1.02 logarithm of the minimal angle of resolution (logMAR) preoperatively to 0.64 +/- 0.43 logMAR at the 36th month (n = 11, P < .001). The mean preoperative BSCVA was 0.88 +/- 0.68 logMAR; after 36 months, this improved to 0.35 +/- 0.34 (P < .001). At the 36th month, UCVA was improved in all eyes (n = 11, range: gain of 1 to 6 lines), whereas BSCVA was improved in 9 eyes (81.8%, range: gain of 2 to 7 lines) and remained unchanged in 2 eyes (18.1%); UCVA was 20/40 or better in 3 eyes (27%) and BSCVA was 20/40 or better in 8 eyes (72.7%). There was a significant reduction in the spherical equivalent refractive error, from -4.40 +/- 1.85 diopters (D) preoperatively to -1.86 +/- 0.60 D (P < .001), and the mean maximum keratometric power decreased from 49.70 +/- 4.32 D to 46.08 +/- 2.84 D (P < .001) after 36 months. The mean cylindrical refraction decreased from -4.39 +/- 1.86 D preoperatively to -2.38 +/- 1.35 D at 36 months (P < .001). CONCLUSION: A single 210-degree arc length ICRS implantation using a femtosecond laser for patients with PMCD provides good visual and refractive outcomes.

Comparison of 2 intrastromal corneal ring segment models in the management of keratoconus.

PURPOSE: To compare the outcomes of implantation of 2 models of intrastromal corneal ring segments (ICRS) to manage keratoconus. SETTING: Kartal Training and Research Hospital, Istanbul, Turkey. METHODS: This study evaluated eyes with keratoconus that had implantation of Keraring ICRS (Group A) or Intacs ICRS (Group B). The corneal tunnels were created mechanically or with a femtosecond laser. The uncorrected (UDVA) and corrected (CDVA) distance visual acuities, refraction, keratometry (K) readings (Orbscan II), and complications in the 2 groups were compared. RESULTS: Group A comprised 100 eyes and Group B, 68 eyes. The postoperative increase in UDVA and CDVA was statistically significant in both groups (P<.05). Group A had greater improvement in CDVA than Group B at 6 months and 1 year (both P<.001). At 1 year, the decrease in the mean maximum K power was statistically significant in Group A (51.27 diopters [D] +/- 4.46 [SD] to 47.87 +/- 3.39 D) and in Group B (51.12 +/- 4.54 D to 47.58 +/- 3.66 D) (P<.05). The mean reduction in maximum K was statistically significantly greater in Group A at 6 months and 1 year (P = .018 and P = .024, respectively). There were no statistically significant differences in visual or refractive results between femtosecond laser and mechanical tunnel creation. CONCLUSION: Although both ICRS models were effective and safe in managing keratoconus, the Keraring ICRS led to more improvement in CDVA and UDVA and a greater reduction in the maximum K value.