Manually prepared lamellae for Descemet stripping endothelial keratoplasty (Pachy-DSEK): comparison of four dissection depths / Lamelas manualmente dissecadas para transplante endotelial de córnea (Pachy-DSEK): comparação entre quatro profundidades de dissecção

ABSTRACT Purpose: This study aimed to compare four depths of manual dissection for the preparation of Descemet stripping endothelial keratoplasty lamellae. Methods: Eye bank corneas were randomized into four groups according to dissection depths: Pachy-100 (incision depth = central corneal thickness-safety margin of 100 µm), Pachy-50 (safety margin of 50 µm), Pachy-0 (no safety margin), and Pachy+50 (incision depth = central corneal thickness + 50 µm). All endothelial lamellae were prepared using a standardized method of manual dissection (Pachy-DSEK). The central, paracentral (3.0-mm zone), and peripheral (6.0-mm zone) lamella thicknesses and incision depths were measured by optical coherence tomography. The 3.0-mm and 6.0-mm zone central-to-peripheral thickness ratios were calculated. Results: Endothelial perforation occurred only in the Pachy+50 group (n=3, 30%). Central lamella's thickness in Pachy-100, Pachy-50, Pachy-0, and Pachy+50 groups measured 185 ± 42 µm, 122 ± 29 µm, 114 ± 29 µm, and 58 ± 31 µm, respectively (p<0.001). The overall 3.0- and 6.0-mm C/P ratios were 0.97 ± 0.06 and 0.92 ± 0.14, respectively. Preoperative donor characteristics were not correlated with most thickness outcomes. The planned incision depth correlated significantly with most lamella's thickness parameters (p<0.001). The overall thickness of the lamella negatively correlated with the planned incision depth (p<0.001, r=-0.580). The best outcome was found in the Pachy-0 group, as 75% of the lamellae measured <130 µm and there was no endothelial perforation. Conclusions: By using a standardized method of dissection, most manually prepared lamellae presented a planar shape. Setting the incision depth to the central corneal thickness did not result in endothelial perforation and a high percentage of ultrathin lamellae was achieved.

RESUMO Objetivo: Comparar quatro profundidades de dissecção manual usadas no preparo de lamelas para transplante endotelial. Métodos: Córneas humanas de treinamento disponibilizadas foram randomizadas em quatro grupos: Pachy-100 (profundidade de incisão = espessura corneana central - margem de segurança de 100 µm), Pachy-50 (margem de segurança de 50 µm), Pachy-0 (sem margem de segurança) e Pachy+50 (profundidade de incisão = espessura corneana central + 50 µm). Todas as lamelas foram dissecadas através um método padronizado e já publicado (Pachy-DSEK). As espessuras das lamelas (centro, zona de 3,0mm e zona de 6,0mm) foram medidas com tomografia de coerência óptica. A razão de espessura centro-periferia foi calculada aos 3,0 e 6,0 mm de diâmetro. Resultados: Perfuração endotelial ocorreu apenas no grupo Pachy+50 (n=3, 30%). A espessura central da lamela nos grupos Pachy-100, Pachy-50, Pachy-0 e Pachy+50 foi de 185 ± 42 µm, 122 ± 29 µm, 114 ± 29 µm, e 58 ± 31 µm, respectivamente (p<0,001). As razões C/P aos 3,0 e 6,0 mm foram de 0,97 ± 0,06 e 0,92 ± 0,14, respectivamente. Os parâmetros de características do doador não se correlacionaram com os resultados de espessura de lamela. A profundidade planejada de incisão se correlacionou com a maioria dos parâmetros de espessura de lamela (p<0,001). A espessura de lamela se correlacionou negativamente com a profundidade planejada da incisão (p<0.001, r=-0,580). O melhor resultado foi observado no grupo Pachy-0, em que 75% das lamelas mediram abaixo de 130 µm e não houve perfuração endotelial. Conclusão: Através de um método padronizado de dissecção, a maioria das lamelas endoteliais apresentou uma configuração planar. O planejamento de profundidade de incisão igual à espessura corneana central resultou em alta porcentagem de lamelas ultrafinas sem ocorrência de perfuração.

A case of late-onset Klebsiella oxytoca keratitis treated with topical imipenem after deep anterior lamellar keratoplasty / Caso de ceratite de início tardio por Klebsiella oxytoca tratado com imipenem tópico após ceratoplastia lamelar anterior profunda

ABSTRACT The aim of this study was to discuss a case of late-onset Klebsiella oxytoca keratitis after deep anterior lamellar keratoplasty and its treatment. A 21-year-old female patient presented with redness and effluence in the left eye at 5 months after uncomplicated deep anterior lamellar keratoplasty surgery. In the examination, a single suture was loosened in the superior nasal region and there was an infiltration area and epithelial defect in the graft and recipient bed junction in the area of the loose suture. Topical fortified vancomycin and fortified ceftazidime treatment was started empirically hourly, but there was insufficient response. After K. Oxytoca growth in a swab and suture culture taken from the patient, fortified vancomycin was replaced with fortified imipenem. It was observed that the infiltration area rapidly regressed and the epithelial defect was closed after fortified imipenem treatment. Fortified imipenem may be considered as an alternative treatment, especially in cases in which there is no response to treatment and culture growth is detected.(AU)

RESUMO O objetivo deste estudo é discutir um caso de ceratite tardia por Klebsiella oxytoca, após ceratoplastia lamelar anterior profunda, bem como seu tratamento. Uma paciente de 21 anos apresentou vermelhidão e efluxo no olho esquerdo 5 meses após cirurgia de ceratoplastia lamelar anterior profunda sem complicações. Ao exame, havia uma única sutura solta na região nasal superior e uma área de infiltração com defeito epitelial no enxerto e na junção com o leito receptor na área da sutura solta. Iniciou-se empiricamente um tratamento tópico com vancomicina e ceftazidima fortificada de hora em hora, porém com resposta insuficiente. Após o crescimento de K. oxytoca a partir de cultura de swab e sutura retirados da paciente, a vancomicina fortificada foi substituída por imipenem fortificado. Observou-se que a área de infiltração regrediu rapidamente e que o defeito epitelial foi fechado com o tratamento com imipenem fortificado. O imipenem fortificado pode ser considerado um tratamento alternativo, especialmente nos casos sem resposta ao tratamento e detecção de crescimento na cultura.(AU)

[Cooperation between the department of ophthalmology at the University of Düsseldorf (Germany) and the Fundación Visión in Asunción (Paraguay) as an example of the German hospital partnerships programm]. / Das deutsche Klinikpartnerschaftsprogramm am Beispiel der Kooperation der Klinik für Augenheilkunde des Universitätsklinikums Düsseldorf mit der Fundación Visión in Asunción (Paraguay).

BACKGROUND: A hospital partnership between the University Eye Hospital Düsseldorf (UAK Düsseldorf) and Fundación Visión in Asunción has existed since 2014 based on a memorandum of understanding. Fundación Visión plays a leading role in ophthalmological treatment and prevention of blindness in Paraguay. Since 2016 a program for the promotion of international hospital partnerships of the German government has been in place. MATERIAL AND METHODS: Following a written application in 2016 the hospital partnership Düsseldorf-Asunción is funded by the Federal Ministry for Economic Cooperation in Germany. The aim of the project was to establish modern minimally invasive corneal transplantation techniques with faster postoperative rehabilitation and less follow-up in Paraguay with the help of several activities within a defined schedule. Secondary aims were to obtain first data on the prevalence of eye diseases in a typical patient cohort of the Fundación Visión and to establish an infrastructure for modern eye banking techniques in Paraguay. RESULTS: First a Paraguayan surgeon was trained to carry out Descemet membrane endothelial keratoplasty (DMEK) transplantations in Germany. At the same time, the surgical instruments required for the DMEK technique were purchased and delivered to the Fundación Visión. In September 2018 the first lamellar corneal transplantations were successfully performed in Paraguay by the team from the Fundación Visión under the supervision of an experienced surgical team from Düsseldorf. Subsequently, the split cornea approach using a donor cornea for a posterior and an anterior lamellar keratoplasty (DMEK and DALK) was also implemented in Asunción. In November 2019 epidemiological data on eye diseases were collected during a field campaign of the Fundación Visión in a rural region of Paraguay. In the course of data collection an employee of the University Eye Hospital Düsseldorf learned small incision cataract surgery. In March 2019, a technician from the Fundación Visión was trained in Düsseldorf in corneal tissue culture techniques and preparation of amniotic membrane transplants in the Lions eye bank North-Rhine/Westfalia. CONCLUSION: With the aid of a supported hospital partnership modern minimally invasive corneal transplantation techniques can be successfully transferred to the eye hospital of a developing country and in return surgical skills can be taught to surgeons from Germany who are in training. Therefore, an efficient hospital partnership is the basis for a mutual exchange and is not purely one-way traffic.

Resultados visuales en pacientes operados de queratoplastia lamelar anterior profunda versus queratoplastia penetrante en el queratocono / Visual results in patients operated of deep anterior lamellar keratoplasty versus penetrating keratoplasty in keratoconus

RESUMEN Objetivo: Comparar los resultados visuales de la queratoplastia lamelar anterior profunda versus la queratoplastia penetrante en el tratamiento quirúrgico del queratocono. Métodos: Se realizó un estudio analítico longitudinal prospectivo en 81 pacientes con queratocono, operados de queratoplastia penetrante y queratoplastia lamelar anterior profunda entre los años 2014 y 2018. Se evaluó la edad, el sexo, la agudeza visual corregida, la esfera, el cilindro y el equivalente esférico. Resultados: La media de edad en operados de queratoplastia lamelar anterior profunda fue 27,5 ± 10,0 años, y 33,2 ± 12,9 años en operados de queratoplastia penetrante. En ambos grupos predominó el sexo masculino: 62,5 por ciento en el grupo de queratoplastia lamelar anterior profunda y 63,3 por ciento en el de queratoplastia penetrante. La agudeza visual corregida poscirugía en operados de queratoplastia lamelar anterior profunda fue 0,8 ± 0,19; el cilindro refractivo -3,50 ± 1,50; el equivalente esférico -6,07 ± 3,61, SimK1 de 46,37 ± 2,47 dioptrías y SimK2, 43,05 ± 2,47 dioptrías. En la queratoplastia penetrante, la agudeza visual corregida fue 0,68 ± 0,19; el cilindro refractivo -2,77 ± 0,98 dioptrías; el equivalente esférico -3,68 ± 1,56 dioptrías, SimK1 y SimK2 de 44,58 ± 2,77 dioptrías y 41,40 ± 2,93 dioptrías respectivamente. Conclusiones: Los resultados refractivos son similares en ambas técnicas quirúrgicas(AU)

ABSTRACT Objective: Compare the visual results of deep anterior lamellar keratoplasty versus penetrating keratoplasty in the surgical treatment of keratoconus. Methods: A longitudinal analytical prospective study was carried out in 81 patients with keratoconus, operated of penetrating keratoplasty and deep anterior lamellar keratoplasty between the years 2014 and 2018. The variables analyzed were the age, the sex, the corrected visual sharpness, the sphere, the cylinder and the spherical equivalent. Results: The average of age in operated patients of deep anterior lamellar keratoplasty was 27,5 ± 10,0 years, and 33,2 ± 12,9 years in operated of penetrating keratoplasty. In both groups the masculine sex predominated: 62,5 percent in the group of deep anterior lamellar keratoplasty and 63,3 percent in penetrating keratoplasty. The corrected visual sharpness in operated of queratoplastia lamelar previous deep was 0,8 ± 0,19; the refractive cylinder -3,50 ± 1,50; the spherical equivalent -6,07 ± 3,61, SimK1 of 46,37 ± 2,47 dioptres and SimK2, 43,05 ± 2,47 dioptres. In the penetrating keratoplasty, the corrected visual sharpness was 0,68 ± 0,19; the refractive cylinder -2,77 ± 0,98 dioptres; the spherical equivalent -3,68 ± 1,56 dioptres, SimK1 and SimK2 of 44,58 ± 2,77 dioptres and 41,40 ± 2,93 dioptres respectively. Conclusions: The refractive results are similar in both surgical technicians(AU)

Seguridad de la queratoplastia lamelar anterior profunda versus queratoplastia penetrante en el tratamiento del queratocono / Safety of deep anterior lamellar keratoplasty versus penetrating keratoplasty in the treatment of keratoconus

RESUMEN Objetivo: Comparar las complicaciones de la queratoplastia lamelar anterior profunda y la queratoplastia penetrante en el tratamiento quirúrgico del queratocono. Métodos: Se realizó un estudio analítico longitudinal prospectivo en 81 pacientes operados de queratoplastia con diagnóstico de queratocono. Las variables analizadas fueron el cilindro, el componente esférico, la densidad celular y las complicaciones en el pre- y en el posoperatorio. Para el análisis estadístico se utilizó la prueba t de Student para la comparación de medias para datos pareados en el caso de dos valores promedios. Resultados: En el paciente operado de queratoplastia lamelar anterior profunda el cilindro fue -3,50 ± 1,50; y en la queratoplastia penetrante el resultado fue de -2,77 ± 0,98. La densidad celular posoperatoria fue de 2 333,6 cel/mm2 en la queratoplastia lamelar anterior profunda y de 2 269,3 cel/mm2 en la queratoplastia penetrante. En la queratoplastia lamelar anterior profunda el 75 por ciento evolucionó sin complicaciones, y el 82,7 por ciento presentó queratoplastia penetrante. Las complicaciones más frecuentes para la queratoplastia lamelar anterior profunda fueron la microperforación, el glaucoma secundario y el síndrome de Urretz-Zavalia (12,5 por ciento cada uno) y en la queratoplastia penetrante el rechazo endotelial (18,2 por ciento) y el defecto epitelial (9,1 por ciento). Conclusiones: En la queratoplastia lamelar anterior profunda la pérdida celular endotelial es más lenta en el primer año y las complicaciones son escasas(AU)

ABSTRACT Objetive: Compare the complications of deep anterior lamellar keratoplasty and penetrating keratoplasty in the surgical treatment of keratoconus. Methods: An analytical prospective longitudinal study was conducted of 81 patients undergoing keratoplasty and diagnosed with keratoconus. The variables analyzed were cylinder, spherical component, cell density, and preoperative and postoperative complications. Statistical analysis was based on Student's t-test for comparison of means for paired data in the event of two average values. Results: Cylinder was -3.50 ± 1.50 for deep anterior lamellar keratoplasty and -2.77 ± 0.98 for penetrating keratoplasty. Postoperative cell density was 2 333.6 cell/mm2 for deep anterior lamellar keratoplasty and 2 269.3 cell/mm2 for penetrating keratoplasty. 75 percent of the patients undergoing deep anterior lamellar keratoplasty and 82.7 percent of those undergoing penetrating keratoplasty evolved without any complication. The most common complications were microperforation, secondary glaucoma and Urretz-Zavalia syndrome (12.5 percent each) for deep anterior lamellar keratoplasty, and endothelial rejection (18.2 percent) and epithelial defect (9.1 percent) for penetrating keratoplasty. Conclusions: In deep anterior lamellar keratoplasty endothelial cell loss is slower in the first year and complications are scant(AU)

Indications and techniques of corneal transplantation in a referral center in Colombia, South America (2012-2016).

PURPOSE: To describe the indications and techniques of corneal grafting in a tertiary institution in a middle-sized city in Colombia. METHODS: A retrospective review of surgical reports and medical records of patients undergoing keratoplasty from January 2012 to December of 2016. RESULTS: A total of 346 eyes from 316 patients were included. The first three indications for keratoplasty were: bullous keratopathy (BK) with 46.2% of the cases, active infectious keratitis (22.3%) and the group of corneal dystrophies and degenerations, including Fuchs' endothelial dystrophy (9%). Keratoconus was in the sixth place (4.9%). 73.3% of the procedures were penetrating keratoplasties (n = 255), 21.7% posterior lamellar (n = 75) and 3.5% anterior lamellar (n = 12). While in 2012, 25 cases of endothelial grafts were performed, only 13 were done in 2016. CONCLUSIONS: BK was the first cause of keratoplasty with almost half of the cases, and keratoconus was relegated to sixth place with less than 5%. In comparison, in a study from eye banks from the US, BK was the second and keratoconus was the third indication for corneal grafts. The frequency of endothelial lamellar techniques in our institution decreased from 2012 to 2016. This could have been related to both the long time that the patients had to be on a waiting list, which made them unsuitable candidates for this technique, due to stromal fibrosis, and to the fact that surgeons of our institution had less experience with posterior endothelial grafting than with penetrating keratoplasties.

Femtosecond laser-assisted deep anterior lamellar keratoplasty in phototherapeutic keratectomy versus the big-bubble technique in keratoconus.

AIM: To compare the functional and anatomic results of femtosecond laser (FSL)-assisted deep anterior lamellar keratoplasty (DALK) associated with phototherapeutic keratectomy (PTK) and FSL-assisted DALK performed using the big-bubble technique in keratoconus. METHODS: During the first phase of the study, an electron microscopy histopathology pilot study was conducted that included four unsuitable donor corneas divided into two groups: in FSL group, FSL lamellar cuts were performed on two corneas and in FSL+PTK group, PTK was performed at the stromal beds of two corneas after FSL lamellar cuts were made. During the second phase of the study, a randomized clinical trial was conducted that included two treatment groups of patients with keratoconus: group 1 (n=14 eyes) underwent FSL-assisted DALK associated with PTK and group 2 (n=12 eyes) underwent FSL-assisted DALK associated with the big-bubble technique. The main outcome measures were the postoperative visual acuity (VA) and optical coherence tomography (OCT) measurements, confocal microscopic findings, and contrast sensitivity. RESULTS: In the pilot study, histopathology showed a more regular stromal bed in the FSL+PTK group. In the clinical trial, group 1 had significantly worse best spectacle-corrected VA and contrast sensitivity (P<0.05 for both comparisons). The residual stromal bed measured by OCT was significantly (P<0.05) thicker in group 1. Confocal microscopy detected opacities only at the donor-receptor interface in group 1. CONCLUSION: Patients with keratoconus treated with FSL-assisted DALK performed using the big-bubble technique fare better than treated with FSL-assisted DALK associated with PTK.

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.

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.

Queratoplastia lamelar predescemética para el tratamiento del queratocono / Predescemetic lamellar keratoplasty for treatment of keratoconus

OBJETIVO: describir los resultados de la queratoplastia lamelar profunda en el tratamiento quirúrgico del queratocono en el Servicio de Córnea del Instituto Cubano de Oftalmología "Ramón Pando Ferrer". MÉTODOS: se realizó un estudio descriptivo prospectivo en 7 ojos con queratocono operados de queratoplastia lamelar profunda. Se analizaron las variables edad, sexo, grado de queratocono, agudeza visual preoperatoria y posoperatoria, astigmatismo posquirúrgico, paquimetría y queratometría topográfica a la semana, al mes y a los tres meses de la intervención. La información se procesó a través de frecuencias absolutas, relativas, medias y desviación estándar. RESULTADOS: en el sexo masculino, el 42,9 % tenía entre 18 y 39 años de edad al igual que el grupo de 40-50 años en el sexo femenino. El 57,2 % de los casos presentó queratocono avanzado. En el posoperatorio se encontró que el 71,4 % de los casos poseía una agudeza visual corregida entre 0,1-0,3 y 5-10 dioptrías de astigmatismo posquirúrgico; la paquimetría fue superior a 560 µm en el 85,6 %; la queratometría promedio en el meridiano más fuerte fue de 47,77 y en el meridiano más débil, de 40,01. CONCLUSIONES: la queratoplastia lamelar predescemética es una técnica quirúrgica que ofrece ventajas superiores en relación con las queratoplastias penetrantes.

OBJECTIVE: to describe the results of deep lamellar keratoplasty in the surgical treatment of keratoconus in the Corneal Service of "Ramón Pando Ferrer" Cuban Institute of Ophthalmology. METHODS: a prospective descriptive study of 7 eyes with moderate keratoconus who underwent predescemetic lamellar keratoplasty. The universe consisted of 7 eyes fom patients who met the criteria for deep lamellar keratoplasty surgery. The variables age, sex, degree of keratoconus, pre-and postoperative visual acuity, postoperative astigmatism, topographic keratometry and pachymetry after a week, a month and three months of the surgery. Data were analyzed by using absolute, relative, mean frequencies and standard deviations. RESULTS: the 18-36 year age group in males represented 42,9 % as the 40-50 years-old group in females. In the studied group, 57,2 % of patients had advanced keratoconus. On the third postoperative month, 71,4 % of patients had visual acuity ranging 0,1 to 0,3 and 5-10 postsurgical astigmatism diopters. Pachymetry observed in 85,6 % of patients was higher than 560 um. The average keratometric value in the strongest meridian was 59,43 preoperatively and 47,77 postoperatively. In the weakest meridian, average keratometry was 50,28 and postoperative average amounted to 40,01. CONCLUSIONS: predescemetic lamellar keratoplasty is a surgical technique providing greater advantages if compared to penetrating keratoplasty.

Novel spatula and dissector for safer deep anterior lamellar keratoplasty / Uso de espátula e dissector para otimização da ceratoplastia lamelar anterior profunda (DALK)

Objective: We describe a novel spatula and dissector to facilitate the big-bubble technique in deep anterior lamellar keratoplasty (DALK). Methods: A 29-year-old man who was diagnosed with bilateral keratoconus underwent deep anterior lamellar keratoplasty (DALK). After 350μm partial thickness incision of the recipient cornea, the Bonfadini dissector was inserted at the deepest point in the peripheral incision and could be advanced to the center of the cornea safely because of its "semi-sharp" tip. After achieving the big-bubble (BB) separation of Descemet membrane (DM) from the overlying stroma, the anterior stromal disc was removed. Viscoelastic material was placed on the stromal bed to prevent uncontrolled collapse and perforation of DM during the paracentesis blade incision into the BB. We could detect the safe opening of the BB using the Bonfadini dissector by the leakage of air bubbles into the viscoelastic material. After injecting viscoelastic material into the BB space, we inserted the Bonfadini spatula into the bigbubble safely because of its curved profile and blunt edges. The groove along the length of the Bonfadini spatula enables safe and efficient incision or the residual stromal tissue using the pointed end of a sharp blade while protecting the underlying DM. After removal of posterior stroma, the donor button was sutured with 16 interrupted 10-0 nylon sutures. Results: This technique and the use of the Bonfadini spatula and dissector facilitate exposure of Descemet membrane. Conclusion: The smooth Bonfadini DALK spatula and dissector facilitate safe and efficient completion of DALK surgery. .

Objetivo: Descrevemos o uso de novos instrumentais cirúrgicos para facilitar a técnica de "big-bubble" na ceratoplastia lamelar anterior profunda (DALK). Métodos: Paciente masculino, 29 anos, foi diagnosticado com ceratocone bilateral e submetido à ceratoplastia lamelar anterior profunda (DALK). Após incisão da córnea receptora numa profundidade de 350μm de espessura parcial, o dissector Bonfadini foi inserido no ponto mais profundo da incisão periférica e pode avançar para o centro da córnea com segurança devido à sua ponta semiafiada. Depois de realizar a "big-bubble" (BB) e atingir a separação da Membrana de Descemet (MD) do estroma sobrejacente, o disco corneano de estroma anterior foi removido. Um viscoelástico foi colocado sobre o leito do estroma remanescente para impedir o colapso não-controlado e perfuração da MD durante a incisão na BB com lâmina de paracentese. Verificamos segurança no rompimento do estroma remanescente com o auxílio do dissector Bonfadini, para liberação da bolha de ar da BB através do viscoelástico. Depois de injetar o viscoelástico no espaço da BB, inserimos a espátula Bonfadini neste espaço, o que demonstrou-se seguro devido ao formato curvo e das bordas arredondadas do instrumental. A chanfradura ao longo do comprimento da espátula Bonfadini permite a incisão pela ponta de uma lâmina afiada, protegendo assim a MD subjacente. Após a remoção do estroma posterior, o botão doador foi suturado com 16 pontos interrompidos de fio nylon 10.0. Resultados: Esta técnica e o uso da espátula Bonfadini e dissector facilitam a exposição de membrana de Descemet. Conclusão: A superfície lisa da espátula Bonfadini e dissector, facilitam a realização segura e eficiente da ceratoplastia lamelar anterior profunda (DALK). .

Queratoplastia lamelar profunda asistida por tunelizador / Deep anterior lamellar keratoplasty assisted by prolate system

Objetivo: describir una nueva técnica quirúrgica para realizar queratoplastia lamelar profunda que facilita la disección de planos corneales a un espesor predeterminado, utilizando instrumental con el cual el cirujano de córnea está familiarizado. Métodos: se describe el caso de una paciente de 32 años con queratocono avanzado sin antecedente de hidrops, cicatrices estromales de la córnea o cirugía previa. Se realizó queratoplastia lamelar profunda en el ojo izquierdo inicialmente y tres meses después en el ojo derecho efectuando el procedimiento a profundidad conocida utilizando instrumental para implante de segmentos intraestromales Intacs® (Addition Technology, Inc., Fremont, CA). Se determinó un plano corneal con el disector de Melles (DORC®, Spijkenisse, Países Bajos) con posterior inyección de viscoelástico para su separación y realización del corte con trépanos de Barron (Katena products, inc. Denville, USA) para donante y receptor de un mismo diámetro (8mm) con sutura combinada con nylon 10-0 (Ethicon, Inc, San Angelo, USA). Resultados: se realizó seguimiento a 4 años con una AVSC de 20/150+1 OD y 20/80-1 OI. La mejor visión corregida lejana fué de 20/25 en OD y 20/20- en el OI. Conclusiones: la queratoplastia lamelar profunda asistida por tunelizador corneal promete ser una técnica segura que permite efectuar la disección a una profundidad planeada sin penetrar a cámara anterior. Se observaron excelentes resultados con una técnica amigable para el cirujano de córnea sin incrementar significativamente el tiempo quirúrgico y además, permitiendo obtener las ventajas al preservar el endotelio corneal con una técnica con cámara cerrada.

Purpose: to describe a new surgical technique for deep lamellar keratoplasty which facilitates corneal lamellar dissection to a predetermined thickness using instruments known by a corneal surgeon to implant Intacs intrastromal ring segments. Methods: We described a case of a 32 year old patient without history of hydrops, corneal stromal scars or previous corneal surgery. Deep lamellar keratoplasty was performed initially in the left eye and three months later in the right eye performing procedure in a known depth using Intacs® Prolate System (Addition Technology, Inc. Fremont, CA). Lamellar corneal dissection was performed with Melles dissector (DORC®, Spijkenisse Netherlands) and viscoelastic substance was injected to dissect planes. Trephination was performed with Barron-Hessburg corneal system (Katena products, inc. Denville, USA) with same size for donor and recipient (8mm) and sutured with a combined 10-0 Nylon suture technique (Ethicon, Inc, San Angelo, USA). Outcome: 4-years follow-up has show an UCVA of 20/150(+1) OD and 20/80(-1) OS. Best corrected distance vision of 20/25 OD and 20/208(-1) in OS were achieved. Conclusions: prolate system corneal assisted deep anterior lamellar keratoplasty promises to be a safe and novel technique allowing corneal dissection to a planned depth without anterior chamber penetration. Excellent results in a friendly technique to any corneal surgeon offers standard surgical time and the advantage to preserve recipient endothelium layer in a closed anterior chamber surgical technique.

Nueva variante de queratoplastia lamelar anterior profunda por abordaje esclerolimbal con técnica de viscodisección / New variant of deep anterior lamellar keratoplasty through sclerolimbal approach with the viscodisection technique

Objetivos: describir las características de la nueva variante de queratoplastia lamelar anterior profunda, por abordaje desde la zona esclerolimbal empleando técnica de viscodisección y, analizar los resultados logrados en la cirugía experimental. Métodos: el procedimiento fue realizado en el Instituto Cubano de Oftalmología Ramón Pando Ferrer, a 10 globos oculares humanos no útiles para trasplante. A través de incisión radial a nivel de la esclera adyacente al limbo se diseca hasta visualizar el tejido corneal más oscuro que indica el plano predescemético. Por el espacio creado, se avanza e inyecta viscoelástico desprendiendo controladamente la membrana de Descemet y endotelio.Resultados: en todos los ojos se pudo completar el procedimiento hasta lograr la disección de la membrana de Descemet. En ocho de ellos (80 porciento), no se produjo ninguna complicación intraoperatoria, en un ojo (10 porciento), hubo una perforación periférica de la membrana de Descemet, el proceder fue completado satisfactoriamente por otra incisión similar. En otro ojo (10 porciento), se produjo ruptura de la Descemet al inyectar viscoelástico para ampliar el desprendimiento. En el total de los casos se logró una disección que permitió aislar la membrana de Descemet transparente, con una superficie lisa y homogénea. El tiempo quirúrgico promedio fue de 18,4 minutos.Conclusiones: la técnica propuesta resultó segura y rápida en globos oculares enucleados. La disección se realiza en un área periférica de más seguridad. Este proceder también puede resultar de utilidad en la disección de la Descemet para la queratoplastia endotelial de la membrana de la Descemet

Objectives: to describe the characteristics of the new variant of deep anterior lamellar keratoplasty through approach from the sclerolimbal area and using the viscodisection technique, and to analyze the results achieved in this experimental surgery.Methods: the procedure was performed in 10 human eyeballs not useful for transplantation purposes at "Ramon Pando Ferrer" Cuban Institute of Ophthalmology. Through a radial incision at the sclera adjacent to the limbus, one dissected until the darker corneal tissue was visualized, thus indicating the pre-Descemet plane. By means of the created space, one moved forward and injected visco-elastic substance to detach in a controlled way the Descemet membrane and the endothelium.Results: it was possible to complete the procedure in all the eyes until the dissection of Descement membrane was achieved. Eight of the eyes (80%) did not show any intraopeative complication, one (10 percent) suffered peripheral perforation of Descement membrane, but the procedure was completed satisfactorily by making another similar incision. The other eye (10 percent) underwent rupture of the Descemet membrane when the visco-elastic substance was injected to extend the detachment. In all the cases, it managed to dissect and isolate the transparent Descemet membrane with smooth and homogeneous surface. The surgical time was 18.4 minutes.Conclusions: the suggested technique proved to be safe and rapid in the enucleated eyeballs. The dissection was practiced in a safer peripheral area. This procedure can also be useful for dissection of Descemet membrane aimed at endothelial keratoplasty of the mentioned membrane

Corneal transplantation at an ophthalmological referral center in Colombia: indications and techniques (2004-2011).

PURPOSE: To analize changing trends in indications and surgical techniques of corneal transplantation at an ophthalmological tertiary referral center in Colombia over a 7 year period. METHODS: A retrospective analysis was performed of medical records from patients who underwent corneal transplantation surgeries at Fundación Oftalmológica de Santander (FOSCAL) in Bucaramanga, Colombia, between August 2004 and August 2011. RESULTS: During this period from a total of 450 corneal transplants performed, we had access to 402 medical records (89.4%). The patients' mean age was 55. Leading indications were: pseudophakic/aphakic bullous kerathopathy (PBK/ABK) (34.6%), corneal scar (15.7%), active infectious keratitis (14.4%) and keratoconus (12.7%). During the first period (2004-2007) PBK/ABK was the leading indication, followed by stromal opacities and keratoconus. During the second period (2008-2011) PBK/ABK remained the leading indication. Infectious keratitis, however, became the second most common indication. Stromal opacities and keratoconus, moved to third and fourth, respectively. All transplants performed in the first period (2004-2007) were penetrating keratoplasties. In the second period (2008-2011) 18.7% of the procedures were performed using the Descemet's stripping automated endothelial keratoplasty technique (DSAEK). CONCLUSIONS: Similar to other international results, PBK/ABK was the leading indication for corneal transplantation at our institution. Keratoconus is becoming a less common indication for keratoplasty in our institution. Infectious keratitis remains a frequent indication for corneal transplantation in this geographical area. In our institution we started performing DSAEK in 2009, and it is emerging as the procedure of choice in corneal diseases that involve only the endothelial layers.

Clinical and histologic study of autogenous oral mucosa in experimental lamellar ketatoplasty / Estudo clínico e histológico da mucosa oral autógena na ceratoplastia lamelar experimental

Eight male dogs of non-specified breed, weighing about 12,4 kg, were subjected to surgical oral mucosa detachment using among others a 5 mm diameter trepan followed by it fixation on 4,5 mm diameter corneal lesion made in an eye, using 9-0 nylon thread in interrupted simple suture pattern. The animals were divided to 4 groups constituted by 2 animals, for histologic study at 15, 30, 45, 60 days of post surgical phase. Meanwhile, clinical findings such as blepharospasm, opacity, neovascularization, ocular discharge, chemosis and characteristics of the graft (vascularization, pigmentation and adhesiveness), were qualitative and quantitatively evaluated at 0-2 days, 3-7 days, 8-15 days, 16-30 days and 31-60 days of postoperative period. Blepharospasm and chemosis were more intense at initial periods, corneal opacity and vascularization (of cornea and grafts) at intermediate periods, both with regressing tendency on the latest periods. Serous mucous exsudate was predominant in higher degrees at the initial and intermediate phases and was absent on the later phases. Clinically, the integration of the graft was verified at 15th day. Pigment deposition was seen on two animals on the later periods. The microscopic study revealed on initial and intermediate periods a thick epithelium in comparasion with the underlying cornea, with vacuolization of the inmost cells, intense fibroplasia a

Oito cães sem raça definida, machos, com peso corpóreo médio de 12,4 kg, foram submetidos a procedimentos cirúrgicos de retirada de fragmento da mucosa oral com auxílio de trépano de 5 mm com posterior aplicação sobre lesão corneana de 4,5 mm de diâmetro, produzida em um dos olhos, aplicando-se sutura simples interrompida com fio de náilon 9-0. Os animais foram divididos em 4 grupos compostos por 2 animais, para estudo histológico aos 15, 30, 45, 60 dias de pós-operatório. Simultaneamente, realizou-se estudo clínico nos períodos de 0-2 dias, 3-7 dias, 8-15 dias, 16-30 dias e 31-60 dias de pós-operatório. Blefarospasmo e quemose foram mais intensos nos períodos iniciais e opacidade corneana e vascularização (da córnea e enxerto) nos períodos intermediários, ambos com tendência de regressão nos períodos tardios. A secreção predominante foi seromucosa, sendo mais incidente nas fases iniciais e intermediárias com ausência nos tardios. Clinicamente, a integração do enxerto foi verificada no 15º dia. O estudo microscópico revelou para os períodos iniciais e intermediários intensa fibroplasia e deposição de fibras colágenas em arranjo desorganizado e vascularização do enxerto de intensa a leve entre 15º e 30º dia. Infiltrado polimorfonuclear foi observado no 15º dia, em grau discreto. Infiltrado linfoplasmocitário foi predominantemente, em grau discreto a moderado, entre o 30º e 60º d

Clinical and histologic study of autogenous oral mucosa in experimental lamellar ketatoplasty / Estudo clínico e histológico da mucosa oral autógena na ceratoplastia lamelar experimental

Eight male dogs of non-specified breed, weighing about 12,4 kg, were subjected to surgical oral mucosa detachment using among others a 5 mm diameter trepan followed by it fixation on 4,5 mm diameter corneal lesion made in an eye, using 9-0 nylon thread in interrupted simple suture pattern. The animals were divided to 4 groups constituted by 2 animals, for histologic study at 15, 30, 45, 60 days of post surgical phase. Meanwhile, clinical findings such as blepharospasm, opacity, neovascularization, ocular discharge, chemosis and characteristics of the graft (vascularization, pigmentation and adhesiveness), were qualitative and quantitatively evaluated at 0-2 days, 3-7 days, 8-15 days, 16-30 days and 31-60 days of postoperative period. Blepharospasm and chemosis were more intense at initial periods, corneal opacity and vascularization (of cornea and grafts) at intermediate periods, both with regressing tendency on the latest periods. Serous mucous exsudate was predominant in higher degrees at the initial and intermediate phases and was absent on the later phases. Clinically, the integration of the graft was verified at 15th day. Pigment deposition was seen on two animals on the later periods. The microscopic study revealed on initial and intermediate periods a thick epithelium in comparasion with the underlying cornea, with vacuolization of the inmost cells, intense fibroplasia a

Oito cães sem raça definida, machos, com peso corpóreo médio de 12,4 kg, foram submetidos a procedimentos cirúrgicos de retirada de fragmento da mucosa oral com auxílio de trépano de 5 mm com posterior aplicação sobre lesão corneana de 4,5 mm de diâmetro, produzida em um dos olhos, aplicando-se sutura simples interrompida com fio de náilon 9-0. Os animais foram divididos em 4 grupos compostos por 2 animais, para estudo histológico aos 15, 30, 45, 60 dias de pós-operatório. Simultaneamente, realizou-se estudo clínico nos períodos de 0-2 dias, 3-7 dias, 8-15 dias, 16-30 dias e 31-60 dias de pós-operatório. Blefarospasmo e quemose foram mais intensos nos períodos iniciais e opacidade corneana e vascularização (da córnea e enxerto) nos períodos intermediários, ambos com tendência de regressão nos períodos tardios. A secreção predominante foi seromucosa, sendo mais incidente nas fases iniciais e intermediárias com ausência nos tardios. Clinicamente, a integração do enxerto foi verificada no 15º dia. O estudo microscópico revelou para os períodos iniciais e intermediários intensa fibroplasia e deposição de fibras colágenas em arranjo desorganizado e vascularização do enxerto de intensa a leve entre 15º e 30º dia. Infiltrado polimorfonuclear foi observado no 15º dia, em grau discreto. Infiltrado linfoplasmocitário foi predominantemente, em grau discreto a moderado, entre o 30º e 60º d