Zeki Tunc

Evaluation of intrastromal corneal ring segments for treatment of post-LASIK ectasia patients with a mechanical implantation technique.

Aim: To evaluate the clinical outcomes of Keraring segment implantation in patients with post- laser-assisted in situ keratomileusis (LASIK) ectasia, using a mechanical implantation technique. Materials and Methods: Twelve eyes of 10 patients with post-LASIK ectasia were enrolled. Intracorneal ring segments (ICRS) were implanted after dissection of the tunnel using Tuncs specially designed dissector under suction. A complete ophthalmic examination was performed, including uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), spherical equivalent, keratometric (K) readings, inferosuperior asymmetry index (ISAI), and ultrasound pachymetry. All 3, 6, and 12-month follow-ups were completed, and statistical analysis was performed. Results: The mean preoperative UDVA for all eyes was 1.28 ± 0.59 logMAR. At 12 months, the mean UDVA was 0.36 ± 0.19 logarithm of the Minimum Angle of Resolution (logMAR) (P=0.002), and the mean preoperative CDVA was 0.58 ± 0.3 logMAR, which improved to 0.15 ± 0.12 (P=0.002) at 1 year. There was a significant reduction in cylindrical refractive and spherical equivalent refractive error from –5.29 ± 2.47 diopters (D) and –5.54 ± 5.04 D preoperatively to –1.47 ± 0.71 D and –0.74 ± 1.07 D (P=0.001, P=0.002), respectively, at 1 year. In the same period, the mean K- readings improved from 47.93 ± 4.84 D to 40.87 ± 2.36 D (P=0.002), and the mean ISAI improved from 5.34 ± 3.05 to 2.37 ± 1.68 (P=0.003). No significant changes in mean central corneal thickness were observed postoperatively. There were no major complications during or after surgery. Conclusion: ICRS implantation using a unique mechanical dissection technique is a safe and effective treatment for post-LASIK ectasia. All parameters showed improvement at 1-year follow-up.

Outcomes of torsional microcoaxial phacoemulsification using tips with 30-degree and 45-degree aperture angles

Purpose To compare the safety and efficacy of Ozil Intelligent Phaco torsional microcoaxial phacoemulsification surgeries performed using 30‐degree and 45‐degree aperture angled tips. Setting Maltepe University School of Medicine Department of Ophthalmology, Istanbul, Turkey. Design Comparative case series. Methods Eyes were assigned to 2.2 mm microcoaxial phacoemulsification using the torsional mode with a 45‐degree (Group 1) or 30‐degree (Group 2) aperture angled tip. A quick‐chop surgical technique was used. The primary outcome measures were ultrasound time (UST), cumulative dissipated energy (CDE), longitudinal and torsional ultrasound (US) amplitudes, mean surgical time, mean balanced salt solution volume used, and mean central corneal thickness (CCT) changes. Results The mean UST, CDE, and longitudinal and torsional US amplitudes were 58.21 seconds ± 33.81 (SD), 7.74 ± 6.23, 0.45 ± 0.30, and 26.30 ± 12.60 in Group 1 and 63.83 ± 23.42 seconds, 12.36 ± 6.75, 0.23 ± 0.26, and 44.65 ± 14.38 in Group 2, respectively. The mean CDE and torsional amplitudes were significantly lower in Group 1 (P=.002 and P=.001, respectively). The mean balanced salt solution volume was 73.30 ± 19.87 cc in Group 1 and 74.30 ± 19.44 cc in Group 2 (P=.821). The mean CCT change was 52.40 ± 38.08 &mgr;m and 99.35 ± 47.14 &mgr;m, respectively (P<.001). Conclusion Torsional phacoemulsification performed with a 45‐degree aperture angled tip provided more effective lens removal with a lower CDE and less CCT change than a 30‐degree aperture angled tip. Financial Disclosure No author has a financial or proprietary interest in any material or method mentioned.

Outcomes of torsional microcoaxial phacoemulsification performed by 12-degree and 22-degree bent tips.

Purpose To compare the safety and efficacy of Ozil Intelligent Phaco torsional microcoaxial phacoemulsification surgeries performed with 12‐degree and 22‐degree bent tips using the Infiniti Vision System. Setting Maltepe University School of Medicine Department of Ophthalmology, Istanbul, Turkey. Design Comparative case series. Methods Eyes were assigned to 2.2 mm microcoaxial phacoemulsification using the torsional mode with a 22‐degree bent tip (Group 1) or a 12‐degree bent tip (Group 2). The primary outcome measures were ultrasound time (UST), cumulative dissipated energy (CDE), longitudinal and torsional ultrasound (US) amplitudes, mean surgical time, mean volume of balanced salt solution used, and surgical complications. Results Both groups included 45 eyes. The mean UST, CDE, longitudinal US amplitude, and torsional US amplitude were 65 seconds ± 27.23 (SD), 11.53 ± 6.99, 0.22 ± 0.26, and 42.86 ± 15.64, respectively, in Group 1 and 84 ± 45.04 seconds, 16.68 ± 10.66, 0.48 ± 0.68, and 46.27 ± 14.74, respectively, in Group 2. The mean UST, CDE, and longitudinal amplitudes were significantly lower in Group 1 (P=.003, P=.008, and P=.022, respectively). The mean volume of balanced salt solution was 73.33 ± 28.58 cc in Group 1 and 82.08 ± 26.21 cc in Group 2 (P=.134). Conclusion Torsional phacoemulsification performed with 22‐degree bent tips provided more effective lens removal than 12‐degree bent tips, with a lower UST and CDE. Financial Disclosure No author has a financial or proprietary interest in any material or method mentioned.

Comparison of Two Different Ultrasound Methods of Phacoemulsification

PURPOSE To compare the safety and efficacy of microcoaxial phacoemulsification surgeries performed with the OZil Intelligent Phaco torsional mode (Alcon Laboratories, Inc., Fort Worth, USA) and combined torsional/longitudinal ultrasound mode using 45 degree aperture angled tips. DESIGN Prospective randomized clinical trial. METHODS setting: Maltepe University, Istanbul. patient population: Eighty eyes of 80 cataract patients were randomly assigned to 2.2 mm microcoaxial phacoemulsification using the OZil Intelligent Phaco torsional mode (Group 1) or combined torsional/longitudinal ultrasound mode (Group 2). observation procedure: Intraoperative fluid and energy usage and postoperative examinations were evaluated. main outcome measures: Ultrasound time, cumulative dissipated energy, longitudinal and torsional ultrasound amplitudes, mean operation time, mean volume of fluid used, and surgical complications. RESULTS Both groups included 40 eyes. Mean ultrasound time, cumulative dissipated energy, and longitudinal and torsional ultrasound amplitudes in Group 1 were 58.21±33.81 seconds, 7.74±6.23, 0.45±0.30, and 26.30±12.60%, respectively, and these parameters in Group 2 were 64.75±30.23 seconds, 12.61±6.21, 26.32±5.85, and 40.98±8.33%, respectively. Cumulative dissipated energy and longitudinal and torsional amplitudes were found to be significantly lower in Group 1 (P=.001, P<.001, P<.001). Mean volumes of fluid used in Groups 1 and 2 were 73.30±19.87 cc and 107.07±21.82 cc, respectively (P<.001). CONCLUSION With the aid of a 45 degree aperture angled tip, the OZil Intelligent Phaco torsional mode provided more effective lens removal than the combined torsional/longitudinal ultrasound mode, with a lower cumulative dissipated energy and volume of fluid used.

Ozil IP torsional mode versus combined torsional/longitudinal microcoaxial phacoemulsification.

Purpose. To compare the safety and efficacy of microcoaxial phacoemulsification surgeries performed with the Ozil Intelligent Phaco (IP) torsional mode and combined torsional/longitudinal ultrasound (US) mode using the Infiniti Vision System (Alcon Laboratories). Methods. In this prospective randomized comparative study, 60 eyes were assigned to 2.2-mm microcoaxial phacoemulsification using the Ozil IP torsional mode (group 1) or combined torsional/longitudinal US mode (group 2). The primary outcome measures were US time (UST), cumulative dissipated energy (CDE), longitudinal and torsional ultrasound amplitudes, mean operation time, mean volume of balanced salt solution (BSS) used, and surgical complications. Results Both groups included 30 eyes. Mean UST, CDE, and longitudinal and torsional ultrasound amplitudes in group 1 were 1 minute 15±34.33 seconds, 8.74±5.64, 0.43±0.74, and 25.56±8.56, respectively, and these parameters in group 2 were 1 minute 40±51.44 seconds, 9.28±5.99, 3.64±1.55, and 3.71±1.34, respectively. UST and longitudinal amplitudes were found to be significantly low in group 1 (p<0.001, p<0.001), whereas torsional amplitude was found to be significantly high in this group (p=0.001). Mean volumes of BSS used in groups 1 and 2 were 63.30±18.00 cc and 84.50±28.65 cc, respectively (p=0.001). Conclusions. The Ozil IP torsional mode may provide more effective lens removal than the combined torsional/longitudinal US mode with a lower UST and volume of BSS used.

Evaluation of intrastromal corneal ring segments for treatment of keratoconus with a mechanical implantation technique

Purpose: To evaluate the clinical outcomes of intrastromal corneal ring segment (ICRS) implantation in patients with keratoconus using a mechanical implantation technique. Materials and Methods: Thirty eyes of 17 patients with keratoconus were enrolled. ICRSs (Keraring) were implanted after dissection of the tunnel using Tuncs specially designed dissector under suction. A complete ophthalmic examination was performed, including uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), spherical equivalent, keratometric readings, inferosuperior asymmetry index (ISAI), and ultrasound pachymetry. All 3-, 6-, and 12-month follow-ups were completed, and statistical analysis was performed. Results: The mean preoperative UDVA for all eyes was 1.36 ± 0.64 logMAR. At 12 months, the mean UDVA was 0.51 ± 0.28 logMAR (P = 0.001), and the mean preoperative CDVA was 0.57 ± 0.29 logMAR, which improved to 0.23 ± 0.18 (P = 0.001) at 1 year. There was a significant reduction in spherical equivalent refractive error from –6.42 ± 4.69 diopters (D) preoperatively to –1.26 ± 1.45 D (P = 0.001) at 1 year. In the same period, the mean K-readings improved from 49.38 ± 3.72 D to 44.43 ± 3.13 D (P = 0.001), and the mean ISAI improved from 7.92 ± 3.12 to 4.21 ± 1.96 (P = 0.003). No significant changes in mean central corneal thickness were observed postoperatively. There were no major complications during and or after surgery. Conclusion: ICRS implantation using a unique mechanical dissection technique is a safe and effective treatment for keratoconus. All parameters improved by the 1-year follow-up.

Supraciliary contraction segments: A new method for the treatment of presbyopia

Background and Objective: To evaluate the safety and effectiveness of supraciliary contraction segment implants (SCSIs) for the treatment of presbyopia. Materials and Methods: This prospective, non-comparative study comprised 10 eyes from five phakic and emmetropic 50-year-old subjects. Preoperative and postoperative near and distance visual acuity, topography, axial length, pachymetry, and intraocular pressure were analyzed. A 5.32-mm long and 0.85-mm thick piece of polymethyl methacrylat (PMMA) and a 5.32-mm long or 0.55-mm thick dried hydrophilic SCSI were placed within the scleral tunnels that were created 2 mm away from the limbus. The 500–550 μm deep tunnels were parallel to the limbus and four segments were implanted per eye. The SCSIs were entirely placed at a depth of approximately 85% in the sclera. Results: The uncorrected distance visual acuity was similar before and after the surgery (0.00 logMAR). The monocular mean uncorrected near visual acuity (UNVA) was 0.5 ± 0.0 before surgery, 0.12 ± 0.10 logMAR at 1 month after surgery, 0.16 ± 0.18 logMAR at 3 months after surgery, and 0.29 ± 0.16 logMAR at the 18-month follow-up. Conclusion: Despite obtaining satisfactory results at 6 months after the surgery, a follow-up of the SCSI intervention at 18 months revealed a regression of the early post-op UNVA improvement caused by a progressive outward movement of SCSIs.

Histologic Findings of Corneal Buttons in Decompensated Corneas With Toxic Anterior Segment Syndrome After Cataract Surgery.

Purpose: To report the histologic findings of penetrating keratoplasty buttons in decompensated corneas with toxic anterior segment syndrome (TASS) after a cataract surgery is performed. Methods: We evaluated the histologic findings of 16 corneal buttons of 16 patients who exhibited decompensation findings because of TASS by means of light microscopy. The patients were classified into 3 groups: The first group consisted of 5 corneal buttons with mild symptoms in which the central corneal thicknesses (CCTs) were ⩽650 &mgr;m, and the visual acuities (VAs) were ≥0.1. The second group consisted of 7 corneal buttons that exhibited moderate symptoms in which the CCTs were between 650 and 750 &mgr;m and the VAs were between 0.1 and 0.03. The third group consisted of 4 corneal buttons that had severe symptoms in which the CCTs were ≥750 &mgr;m and the VAs were ⩽0.03. Results: Light microscopy showed endothelial cell loss, vacuolated and thinned epithelial cell layers, disturbed collagen bonds, and Descemet membrane invaginations in patients in group I. Group II corneal buttons exhibited inflammatory cells (lymphocytes) and extended intercellular space between the epithelial cells, wrinkled Bowman membrane separated from the stroma in some local areas, stromal edema, and early vascularization. In group III, endothelial and epithelial cell layer loss, wrinkled Descemet and Bowman membranes, inflammatory cells, and structurally disturbed collagen bonds located beneath the Bowman membrane, and a greater amount of vascularization in the area of inflammation were observed. Conclusions: The results of the histologic evaluation of the decompensated corneas caused by the TASS are compatible with the clinical severity of the disease. In mild cases, the histologic findings were insignificant; however, when the clinical situation deteriorated, histologic findings became increasingly worse.

Helvacioglu reproducibility index: a new algorithm to evaluate the effects of misalignments on the measurements of retinal nerve fiber layer by spectral-domain OCT.

AIM To evaluate the effect of misalignment on the measurements of retinal nerve fiber layer (RNFL) by spectral-domain optical coherence tomography (OCT). METHODS A total of 42 eyes from 21 healthy young subjects underwent RNFL measurements with RTVue spectral-domain OCT (Optovue Inc., Fremont, California, USA). Two baseline measurements with perfectly aligned central circle to the borders of the optic nerve and four misaligned measurements which were misaligned towards to four quadrants were taken. The differences in RNFL between the baseline and misaligned measurements were analyzed with a new algorithm called Helvacioglu reproducibility index (HRI) which is designed to measure the reproducibility of the scans by evaluating the RNFL changes in the four main quadrants. RESULTS The average RNFL scores of the first two baseline measurements have good correlation (c=0.930) and good reproducibility scores (0.15±0.07). Superior misaligned measurements had significantly lower superior quadrant score and higher inferior quadrant score, similar nasal and little higher temporal scores (P1, P2<0.001, P3=0.553, P4=0.001). Inferior misaligned measurements had significantly higher superior quadrant score and lower inferior quadrant score with similar temporal and little lower nasal scores (P1, P2<0.001, P3=0.315, P4=0.016). Nasal misaligned measurements had significantly higher temporal quadrant score and lower nasal quadrant score with little lower superior and inferior scores (P1, P2, P4<0.001, P3=0.005). Temporal misaligned measurements had significantly higher nasal quadrant score and lower temporal quadrant score with similar superior and little higher inferior scores (P1, P2<0.001, P3=0.943, P4=0.001). CONCLUSION Good alignment of the central circle to the borders of optic nerve is crucial to have correct and repeatable RNFL measurements. Misalignment to a quadrant resulted in falsely low readings at that quadrant and falsely high readings at the opposite quadrant.

Multifokal Progressif Refraktif Difraktif Lens: Optik Tasarım ve Klinik Sonuçları

Özet Amaç: Asiferik bifokal difraktif ve progressif refraktif tasarımlı yeni konsept OptiVisTM göz içi lensi (GİL) uygulanan hastaların görme fonksiyonlarının değerlendirilmesi. Ge reç ve Yön tem: Bu prospektif çalışmada 27 hastanın 52 gözüne 2,5 mm kesiden fakoemülsifikasyon ile katarakt operasyonunu takiben yeni bir multifokal GİL olan OptiVisTM GİL implante edildi. Ameliyatlar 25 hastada da her iki göze ayni seansta bilateral yapıldı. Daha önce farklı multifokal GİL takılmış olan iki hastanın, diğer iki gözüne ise OptiVisTM GİL yerleştirildi. Hastaların monoküler uzak, orta ve yakın görme keskinlikleri ölçüldü ve kontrast duyarlılık testleri yapıldı. Kamaşma, hale, gözlük kullanma sıklığı ve hasta memnuniyeti sorgulandı. So nuç lar: Hastaların yaş ortalaması 71,10±10,60, takip süresi 20,35±13,99 aydı. Operasyondan 6 ay sonra, yapılan ölçümlerde hastaların ortalama monoküler düzeltmesiz görme keskinlikleri; uzak için 0,96±0,11 (ondalık Snellen kartı), yakın için (33 cm) J1,07±0,26 (Jaeger eşeli) ve orta mesafe (60 cm) için J2,25±0,55 bulundu. Ortalama monoküler düzeltilmiş görme keskinlikleri ise sırasıyla 0,97±0,08, J1,05±0,23 ve J2,23±0,54 olarak ölçüldü. Monoküler ortalama kontrast duyarlılık değerleri 6. ayda fotopik koşulda 1,5 cycles per degree (cpd) de 47, 3 cpd de 73, 6 cpd de 61, 12 cpd de 17 ve 18 cpd de 2 bulundu. Hastalarda operasyon sonrası ilk ayda orta şiddette olabilen kamaşma ve halo problemleri 3. ayda 20 hastada (%74,07) hiç ya da çok hafif iken 7 hastada (%25,92) ise orta derecede bulundu. Bir hasta (%3,70) ise bazen uzak görme için gözlük kullanma ihtiyacı duydu. Arka kapsül opasifikasyonu ise 3 gözde (%5,76) tespit edildi. Tar t›fl ma: OptiVisTM katarakt ameliyatlısı hastalarda, difraktif bifokal özelliği ile kontrast kaybı olmadan çok iyi uzak ve yakın görme kazandırdığı gibi progressif refraktif tasarımı sayesinde de oldukça iyi orta mesafe görmesi sağlayarak yüksek bir hasta memnuniyeti oluşturdu. (Turk J Ophthalmol 2012; 42: 326-31) Anah tar Ke li me ler: Katarakt, multifokal apodize difraktif refraktif göz içi lensi, multifokal göz içi lensleri, OptiVisTM multifokal göz içi lensi, fakoemulsifikasyon