Femtosecond laser deep lamellar keratoplasty

We aimed to develop a novel and effective technique for creating a smooth deep lamellar dissection of the cornea using a femtosecond (FS) laser for deep anterior lamellar keratoplasty (DALK), we conducted a retrospective eye bank study. Thirteen fresh human corneas were mounted on an artificial anterior chamber, and deep lamellar cuts were made with a 500?kHz VisuMax FS laser at a level of 50–80 ?m anterior to the Descemet’s membrane (DM). A posterior diameter of 8 mm with a side cut angle of 110° was used for the anterior penetrating side cut. The anterior lamellar tissue was bluntly dissected. The residual posterior stromal beds and side cuts were examined with microscopy and intraoperative optical coherence tomography (OCT) and post?cut endothelial cell evaluations. All corneas revealed a smooth residual posterior stromal bed without any visible irregularities or ridges by microscopy and OCT imaging. Six corneas were suitable for post?cut endothelial cell evaluation 2 days after laser cut, with no significant endothelial cell loss post?laser and blunt dissection of the posterior stroma. FS laser deep lamellar keratoplasty utilizing an ultrafast laser to produce a smooth deep stromal dissection followed by blunt dissection and removal of the anterior stromal tissue yields a consistent and smooth residual stromal bed. The creation of a smooth lamellar dissection in the deep posterior cornea may result in more consistent DALK without the need for air bubble or manual baring of DM that has the risk for DM perforation.

Assessments of tear meniscus height, tear film thickness, and corneal epithelial thickness after deep anterior lamellar keratoplasty / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

OBJECTIVE@#To assess the lower tear meniscus height (LTMH), central tear film thickness (CTFT), and central corneal epithelial thickness (CCET) after deep anterior lamellar keratoplasty (DALK).@*METHODS@#This was a retrospective cross-sectional study of 20 patients who had DALK in one eye over a three-month period. LTMH, CTFT, and CCET of the operated eyes and the unoperated fellow eyes were measured using high-definition optical coherence tomography (HD-OCT). Correlations between three OCT assessments and age, time following surgery, graft size, bed size, and the number of residual sutures were analyzed.@*RESULTS@#Compared to patients with keratoconus, patients with other corneal conditions had significantly higher CCET in the fellow eye (P=0.024). For all patients, CCET in the operated eye was significantly negatively correlated with the number of residual sutures (R=-0.579, P=0.008), and was significantly positively correlated with time following surgery (R=0.636, P=0.003). In the fellow eye, a significant positive correlation was found between age and CCET (R=0.551, P=0.012), and a significant negative correlation between age and CTFT (R=-0.491, P=0.028). LTMH was found to be significantly correlated between operated and fellow eyes (R=0.554, P=0.011). There was no significant correlation between LTMH and age, bed/graft size, time following surgery, or residual sutures (all possible correlations, P>0.05).@*CONCLUSIONS@#Patients with keratoconus tend to have a thinner central corneal epithelium. Corneal epithelium keeps regenerating over time after DALK. DALK did not induce a significant change in tear volume compared with the fellow eye. Postoperative tear function might depend on an individual's general condition, rather than on age, gender, bed/graft size, time following surgery, or residual sutures.

Queratoplastia Lamelar Anterior Profunda asistida con láser de femtosegundo configuración Zig-Zag: Resultados a un año de seguimiento / Deep Anterior Lamellar Keratoplasty in a Zig-Zag Pattern Assisted by Femtosecond Laser: 1 year follow up

Objetivo: Reportar el desenlace luego de 12 meses de seguimiento, en pacientes en los que se realizó una queratoplastia lamelar anterior profunda (DALK) asistida con láser de femtosegundo. Metodología: Se realizó un estudio descriptivo, retrospectivo, mediante revisión de historias clínicas de pacientes sometidos a DALK asistida con láser de femtosegundo (Wavelight FS-200 ® Alcon. Forth Worth, Texas), utilizando la configuración de zig-zag. Las indicaciones de DALK incluyeron queratocono, ectasia post LASIK y leucoma como secuela de queratitis infecciosa. Las variables estudiadas fueron agudeza visual mejor corregida, cilindro queratométrico, refracción final y complicaciones intra y post operatoria. Resultados: En total se incluyeron 10 ojos de 10 pacientes, en todos los ojos se llevó a cabo con éxito femto-DALK y no hubo ninguna complicación intra operatoria. En el postoperatorio se presentó un caso de rechazo estromal, un caso de hipertensión ocular secundario a esteroides y un caso de retraso en la cicatrización. El seguimiento promedio fue de 13, 1 meses (R= 12 ­ 15 meses). La Agudeza Visual Mejor Corregida (AVMC) preoperatoria promedio fue LogMAR 0,96 (R= 0,54 ­ 1,60). La AVMC postoperatoria promedio a los 12 meses fue 0,10 (R= 0,00 ­ 0,17). El equivalente esférico preoperatorio medio fue -12,6 Dioptrias (D) (R= -5,0 a -15,0D) y el postoperatorio fue -2,57 D (R= -0,50 a -6,25 D). El astigmatismo queratométrico preoperatorio medio de -11.5D (R= -7.0 a -23D) y el postoperatorio -2,4 D (R= -0,75 a -3,75 D). Conclusión: La femto-DALK en confi guración Zig-Zag es un procedimiento confiable, con baja tasa de complicaciones intra y postoperatorias. El resultado refractivo es comparable con la queratoplastia penetrante, y ofrece beneficios sobre factores de estabilidad biomecánica y recuperación del paciente en el primer año postoperatorio.

Objective: The aim was to report the surgical outcomes of twelve months follow-up aft er femtosecond laser assisted Zig-zag configuration combined with Deep Anterior Lamellar Keratoplasty (Femto-DALK). Methods: A descriptive, retrospective study, which evaluated and assisted medical records of patients who had undergone deep anterior lamellar keratoplasty (DALK) femtosecond laser assisted. Ten eyes of ten consecutive patients underwent femtosecond (Wavelight FS-200 ® Alcon. Forth Worth, Texas) laser-assisted zig-zag configuration combined with Anwar´s big-bubble technique DALK, from April 2012 to December 2013. The diagnosis of the patients were keratoconus, corneal ectasia and scarring following infectious keratitis. Variables measured were: Best corrected visual acuity, keratometric corneal cylinder, final refraction and intraand postoperative complications were analyzed. Results: The procedure was performed without any complications in all patients. There was only a single case of stromal graft rejection, a case of corticosteroidinduced ocular hypertension and a case of delayed corneal epithelial healing. Mean follow-up period was 13.1 months (R= 12­15 months). The mean preoperative BCVA was LogMAR 0,96 (R= 0,54 ­ 1,60). Th e mean postoperative BCVA at 12th month was 0,054 (R= 0,00 ­0,09). The mean preoperative spherical equivalent (SE) was -12,6 Diopter (D)(R= -5,0 to -24,0D) and postoperative SE was -2,50 D (R=-0,50 to -6,25 D). The measurements of keratometric corneal cylinder preoperative was -11.5D (R= -7.0 a -23D) and postoperative refractive cylinder was -2,4 D (R=-0,75 to -4,00 D). Conclusion: Laser-assisted zig-zag configuration combined with Anwar´s big-bubble technique DALK is a safe procedure. The rate of intra and postoperative complications is low. The refractive outcomes are comparable to penetrating keratoplasty, but better biomechanical stability of the cornea and a faster visual recovery with femtoDALK procedure.

Efecto Hipotensor de la Trabeculoplastia Láser / Hypotensive Eff ect of Laser Trabeculoplasty

Objetivo: Reportar el desenlace luego de 12 meses de seguimiento, en pacientes en los que se realizó una queratoplastia lamelar anterior profunda (DALK) asistida con láser de femtosegundo. Metodología: Se realizó un estudio descriptivo, retrospectivo, mediante revisión de historias clínicas de pacientes sometidos a DALK asistida con láser de femtosegundo (Wavelight FS-200 ® Alcon. Forth Worth, Texas), utilizando la configuración de zig-zag. Las indicaciones de DALK incluyeron queratocono, ectasia post LASIK y leucoma como secuela de queratitis infecciosa. Las variables estudiadas fueron agudeza visual mejor corregida, cilindro queratométrico, refracción final y complicaciones intra y post operatoria. Resultados: En total se incluyeron 10 ojos de 10 pacientes, en todos los ojos se llevó a cabo con éxito femto-DALK y no hubo ninguna complicación intra operatoria. En el postoperatorio se presentó un caso de rechazo estromal, un caso de hipertensión ocular secundario a esteroides y un caso de retraso en la cicatrización. El seguimiento promedio fue de 13, 1 meses (R= 12 ­ 15 meses). La Agudeza Visual Mejor Corregida (AVMC) preoperatoria promedio fue LogMAR 0,96 (R= 0,54 ­ 1,60). La AVMC postoperatoria promedio a los 12 meses fue 0,10 (R= 0,00 ­ 0,17). El equivalente esférico preoperatorio medio fue -12,6 Dioptrias (D) (R= -5,0 a -15,0D) y el postoperatorio fue -2,57 D (R= -0,50 a -6,25 D). El astigmatismo queratométrico preoperatorio medio de -11.5D (R= -7.0 a -23D) y el postoperatorio -2,4 D (R= -0,75 a -3,75 D). Conclusión: La femto-DALK en configuración Zig-Zag es un procedimiento confiable, con baja tasa de complicaciones intra y postoperatorias. El resultado refractivo es comparable con la queratoplastia penetrante, y ofrece beneficios sobre factores de estabilidad biomecánica y recuperación del paciente en el primer año postoperatorio.

Objective: The aim was to report the surgical outcomes of twelve months follow-up after femtosecond laser assisted Zig-zag confi guration combined with Deep Anterior Lamellar Keratoplasty (Femto-DALK). Methods: A descriptive, retrospective study, which evaluated and assisted medical records of patients who had undergone deep anterior lamellar keratoplasty (DALK) femtosecond laser assisted. Ten eyes of ten consecutive patients underwent femtosecond (Wavelight FS-200 ® Alcon. Forth Worth, Texas) laser-assisted zig-zag configuration combined with Anwar´s big-bubble technique DALK, from April 2012 to December 2013. The diagnosis of the patients were keratoconus, corneal ectasia and scarring following infectious keratitis. Variables measured were: Best corrected visual acuity, keratometric corneal cylinder, final refraction and intraand postoperative complications were analyzed. Results: The procedure was performed without any complications in all patients. There was only a single case of stromal graft rejection, a case of corticosteroid induced ocular hypertension and a case of delayed corneal epithelial healing. Mean follow-up period was 13.1 months (R= 12­15 months). The mean preoperative BCVA was LogMAR 0,96 (R= 0,54 ­ 1,60). The mean postoperative BCVA at 12th month was 0,054 (R= 0,00 ­0,09). The mean preoperative spherical equivalent (SE) was -12,6 Diopter (D) (R= -5,0 to -24,0D) and postoperative SE was -2,50 D (R=-0,50 to -6,25 D). The measurements of keratometric corneal cylinder preoperative was -11.5D (R= -7.0 a -23D) and postoperative refractive cylinder was -2,4 D (R=-0,75 to -4,00 D). Conclusion: Laser-assisted zig-zag configuration combined with Anwar´s big-bubble technique DALK is a safe procedure. The rate of intra and postoperative complications is low. The refractive outcomes are comparable to penetrating keratoplasty, but better biomechanical stability of the cornea and a faster visual recovery with femtoDALK procedure.