Non-contact wide-angled visualization with chandelier-assisted scleral buckling for primary uncomplicated rhegmatogenous retinal detachment.

PURPOSE: To report our experience in non-contact wide-angled visualization with chandelier-assisted scleral buckling (SB) in uncomplicated primary rhegmatogenous retinal detachments (RRD). METHODS: Retrospective case series of 282 eyes that underwent non-contact wide-angled visualization with chandelier-assisted SB and were followed for a mean of 13.5 months. RESULTS: There were 160 male patients. The average age was 42.6 years old. There were 262 eyes that were phakic, 18 pseudophakic, and 2 aphakic. Two-thirds of eyes presented with the macula detached. Eyes had an average of 1.6 breaks. The single operation anatomic success rate was 85.1% (240/282). The pre-op visual acuity improved from 1.21 to 0.76 logMAR at 6 months (p < 0.0001). Complications included a case of scleral laceration, choroidal hemorrhage, 3 epiretinal membranes, 1 macular fold, and 4 eyes with buckle exposure. CONCLUSION: Non-contact wide-angled visualization with chandelier-assisted SB compares favorably with conventional SB for primary uncomplicated primary RRD.

Vitreous humor thermodynamics during phacoemulsification.

The purpose of this study is to determine baseline vitreous humor temperature during a combined phacoemulsification and pars plana vitrectomy (PPV) procedure; to determine what is the temperature variation during phacoemulsification; and to compare vitreous temperature to sublingual temperature. The methods used are prospective, interventional and comparative study. Patients with a diagnosis of cataract and vitreous hemorrhage, programed for a combined procedure of phacoemulsification and PPV, were included. Patients were excluded if posterior capsular rupture existed during the anterior segment procedure. A thermoprobe was inserted through a PPV trocar. Measurement of the vitreous temperature was obtained at baseline and throughout phacoemulsification, at the end of every surgical step, and every 5 min. Sublingual temperature was measured with the same probe at the end of the surgery. Room temperature was registered. Seventeen eyes of 17 patients were included. Mean sublingual temperature was 36.5 °C (standard deviation [σ] 0.26 °C). Mean total vitreous temperature was 31.47 °C (σ 2.1 °C). Mean baseline vitreous temperature was 33.04 °C (σ 0.99 °C). Comparison of sublingual temperature with baseline vitreous temperature resulted in a significant difference (t test P < 0.000. 95 % confidence interval 2.93-3.98). Temperature measured by surgical step and surgical time presented a significant decrease in temperature from baseline (Kruskal-Wallis P < 0.000, P = 0.003, respectively). Vitreous humor is significantly hypothermic when compared to sublingual temperature. Vitreous temperature decreases significantly during phacoemulsification.

Versatility of use of fibrin glue in wound closure and vitreo-retinal surgery.

BACKGROUND: Fibrin glue is an absorbable blood-derived product, a biological tissue adhesive which imitates the final stages of the coagulation cascade, it produces a firm clot, forming a seal along the whole length of the wound, the resultant fibrin clot degrades physiologically into granulation tissue 2 weeks after the application. Biological glue has been used extensively in many forms of surgical procedures. Its use in eye surgery has grown lately as we have evidence that showed it was effective in securing conjunctival grafts in pterygium surgery, in securing wounds after glaucoma surgery and more importantly in 20G and 23G vitrectomy. PURPOSE: The aim of this study is to present our experience in the use of fibrin glue in vitreoretinal surgery. MATERIAL AND METHODS: We included 281 eyes of 221 patients who underwent vitreoretinal surgery during the period of May 2009 to July 2012, the preoperative diagnoses were as following: proliferative diabetic retinopathy, rhegmatogenous retinal detachment, macular hole, epiretinal membrane, luxation of cataratous nucleous and cortex, intraocular lens luxation, penetrating trauma, silicone extraction, phaco + IOL + vitrectomy + Ahmed valve implant, vitreous biopsy and optic nerve pit associated to macular detachment. The procedures were performed with Alcon Accurus Surgical System 20-gauge, 23-gauge or a combination of both. We used fibrin glue in all of the 20-gauge sclerotomies and leaking 23-gauge sclerotomies, scleral wound for IOL extraction, conjunctival peritomy for buckle implantation, conjunctiva in Ahmed valve implant, corneal graft in corneal perforation in trauma and leaking corneal wounds for phacoemulsification, in an optic pit, and in subretinal space in a giant retinal tear. RESULTS: We did not use any suture in any of the patients throughout the different procedures, there was no leakage in any wounds in the postoperative period, we found no inflammatory reaction, infection, and whenever we had excess amount, it was trimmed. Two patients presented a small dehiscence of the wound that was corrected in-office with a small amount of fibrin glue in the post-operative period. CONCLUSIONS: Fibrin glue reduces surgical time, it is a good sealant, safe, with minimal allergic or toxic reactions and inflammation, minimizes bleeding, easy to undo and that eventually degrades. This small series shows that fibrin glue is a viable alternative for tissue coaptation in vitreoretinal surgery. However, further studies are required before fibrin glue takes the place of sutures.

[Mexican clinical experience in ocular anti-angiogenic therapy]. / Terapia antiangiogénica ocular: experiencia clínica en México.

Retinal pathological angiogenesis is the leading cause of visual loss in a wide variety of ocular diseases. Some of the examples include: Age-related macular degeneration, diabetic retinopathy and retinopathy associated with prematurity. These last two entities are, in addition, public health problems in developing countries. Recent physiopathological studies, have demonstrated that growth factors play a key role on angiogenesis. Anti-angiogenic therapy came about as an attempt to inhibit the action of growth factors over the process of pathological angiogenesis in order to preserve vision. The objective of this review is to describe Mexico's experience using this therapeutic approach.

Inverted ILM flap, free ILM flap and conventional ILM peeling for large macular holes.

BACKGROUND: To assess closure rate after a single surgery of large macular holes and their visual recovery in the short term with three different surgical techniques. METHODS: Prospective multicenter randomized controlled trial. We included treatment-naïve patients with diagnosis of large macular hole (minimum diameter of > 400 µm). All patients underwent a comprehensive ophthalmological examination. Before surgery, the patients were randomized into three groups: group A: conventional internal limiting membrane peeling, group B: inverted-flap technique and group C: free-flap technique. All study measurements were repeated within the period of 1 and 3 months after surgery. Continuous variables were assessed with a Kruskal-Wallis test, change in visual acuity was assessed with analysis of variance for repeated measurements with a Bonferroni correction for statistical significance. RESULTS: Thirty-eight patients were enrolled (group A: 12, group B: 12, group C: 14). The closure rate was in group A and B: 91.6%; 95% CI 61.52-99.79%. In group C: 85.71%; 95% CI 57.19-98.22%. There were no differences in the macular hole closure rate between groups (p = 0.85). All groups improved ≈ 0.2 logMAR, but only group B reached statistical significance (p < 0.007). CONCLUSIONS: Despite all techniques displayed a trend toward visual improvement, the inverted-flap technique seems to induce a faster and more significant recovery in the short term.

Long-term follow-up of patients with choroidal neovascularization due to angioid streaks.

BACKGROUND: The following case series describes the long-term anatomical and functional outcome of a group of seven patients with choroidal neovascularization (CNV), secondary to angioid streaks (AS), who were treated with antiangiogenic drugs in a pro re nata (PRN) regimen. After the 4-year mark, visual acuity tends to return to pretreatment level. Treatment delays and lack of awareness and self-referral by the patients are believed to be the cause of the PRN regimen failure. PURPOSE: To assess the long-term outcomes (>4 years) of patients with CNV due to AS treated with a PRN regimen of antiangiogenic. METHODS: This was a retrospective, case series, single-center study. We reviewed the electronic medical records from patients with CNV due to AS. From each record, we noted general demographic data and relevant medical history; clinical presentation, changes in best-corrected visual acuity (BCVA) over time, optical coherent tomography parameters, treatment and retreatment details, and systemic associations. Changes in BCVA and central macular thickness were assessed with a Wilcoxon two-sample test, with an alpha value of ≤0.05 for statistical significance. RESULTS: The mean follow-up time was 53.8±26.8 months. BCVA at baseline was: 1.001±0.62 logMAR; at the end of follow-up: 0.996±0.56 logMAR (P=0.9). Central macular thickness at baseline was: 360.85±173.82 µm; at the end of follow-up: 323.85±100.34 µm (P=0.6). Mean number of intravitreal angiogenic drugs: 6±4.16 injections (range 4-15). Mean time between injections was 3.8±2.7 months (range 1.9-5.8 months). CONCLUSION: Despite initial anatomical and functional improvement, patients at the end of the follow-up had no visual improvement after a pro re nata regimen of antiangiogenic drugs. The amount of retreatments, number of recurrences, and time between intravitreal injections were similar to previous reports with shorter follow-up.

Sensitivity, specificity and predictive values of anterior chamber tap in cases of bacterial endophthalmitis.

BACKGROUND: To assess the sensitivity, specificity, positive predictive value and negative predictive value of anterior chamber tap for the diagnosis of bacterial endophthalmitis on a population with high prevalence. METHODS: Retrospective, single centre, case series study. We reviewed all medical records with clinical diagnosis of bacterial endophthalmitis in our hospital from January 1st, 2000 to December 31st 2014. From each record, we documented general demographic data, best corrected visual acuity and vitreous and aqueous tap microbiological results. All cases were further divided according to the endophthalmitis aetiology to perform individual calculations of sensitivity, specificity, positive predictive value, negative predictive value, accuracy and prevalence. We used the results of the vitreous tap as the gold standard for diagnosis of bacterial endophthalmitis. We excluded those records in which the aqueous and vitreous samples were not taken simultaneously or had an incomplete microbiological report. Significance were assessed with chi squared statistics, with an alpha value of 0.05 for statistical significance. RESULTS: A total of 190 cases fulfilled the inclusion/exclusion criteria. Positive culture rate from vitreous samples was 64.74%. Positive culture rate from aqueous sample was 32.11%. Bacteria isolated from aqueous samples matched those isolated from vitreous samples 78.68% of the time. The overall sensitivity was 38.21%, specificity: 75.51%, positive predictive value: 79.66%, negative predictive value: 32.74% (p = 0.08). Subgroup analysis showed that anterior chamber taps in cases of post-surgical endophthalmitis had a moderate to low sensitivity (37.73%), high specificity (93%) and high positive predictive value (95%) (p < 0.04). CONCLUSION: The sensitivity and specificity of anterior chamber tap are low and should not be used for critical therapeutic decisions in patients with suspected bacterial endophthalmitis. In cases of post-surgical endophthalmitis, the result of an anterior chamber tap could be used for therapeutic guidance, but only in conjunction with clinical presentation and in the absence of a better method for diagnosis.

Pars plana vitrectomy and lamina cribrosa puncture in absolute glaucoma.

Two patients with refractory end-stage glaucoma who had no light perception underwent pars plana vitrectomy and lamina cribrosa puncture to relieve pain and decrease intraocular pressure. The patients presented with blind, painful eyes and high intraocular pressure (> 40 mm Hg). After the procedure, the pain was relieved and the intraocular pressure was lowered in both cases. The patients remained asymptomatic. Pars plana vitrectomy and lamina cribrosa puncture might be related to the decrease of intraocular pressure, probably by facilitating drainage of aqueous humor through the optic nerve.

Perfluorocarbon-perfused 23 gauge three-dimensional vitrectomy for complicated diabetic tractional retinal detachment.

BACKGROUND: Perfluorocarbon liquid (PCL)-perfused vitrectomy has been shown in previous studies to be feasible, safe, and to have advantages in managing complicated cases of tractional retinal detachment. The present study had the objectives of describing the anatomical results and measuring surgical time and PCL consumption when combining PCL-perfused techniques with modern vitrectomy equipment. METHODS: A prospective, interventional consecutive case series was investigated. We enrolled patients with diabetic tractional retinal detachment, complicated by proliferative vitreoretinopathy and poor vision. A 23 gauge PCL-perfused vitrectomy was done with three-dimensional settings. During the procedure, we assessed the degree of surgical bleeding, visualization quality, and difficulty of membrane dissections. Visual acuity, intraocular pressure, and anatomical success were assessed at one and 3 months of follow-up. RESULTS: Twelve patients were enrolled in this study. There were no statistical significant changes in intraocular pressure and visual acuity throughout the follow-up period. Surgery was performed in a hemorrhage-free environment in almost all cases, with good visualization and low technical difficulty. The mean complete surgical time was 94.92 ± 25.03 minutes. The mean effective vitrectomy time was 22.50 ± 19.04 minutes and the mean PCL consumption was 25.08 ± 9.76 mL, with a speed of 1.11 mL/minute. Anatomical success was 67% at 3 months. CONCLUSION: Although the technique proved to have some advantages in managing complicated cases of diabetic tractional retinal detachment, there was a high consumption of PCL. A redesign of the entire system is needed in order to decrease the amount of PCL needed for the technique.

Intraocular and systemic levels of vascular endothelial growth factor in advanced cases of retinopathy of prematurity.

PURPOSE: To measure vitreous, aqueous, subretinal fluid and plasma levels of vascular endothelial growth factor in late stages of retinopathy of prematurity. METHODS: Interventional study. We enrolled patients with clinical diagnoses of bilateral stage V retinopathy of prematurity, confirmed by b-scan ultrasound and programmed for vitrectomy. During surgery we took samples from blood, aqueous, vitreous, and subretinal fluids. The vascular endothelial growth factor concentration in each sample was measured by ELISA reaction. A control sample of aqueous, vitreous and blood was taken from patients with congenital cataract programmed for phacoemulsification. For statistical analysis, a Mann-Whitney and a Wilcoxon W test was done with a significant P value of 0.05. RESULTS: We took samples of 16 consecutive patients who met the inclusion criteria. The vascular endothelial growth factor levels in the study group were: aqueous, 76.81 ± 61.89 pg/mL; vitreous, 118.53 ± 65.87 pg/mL; subretinal fluid, 1636.58 ± 356.47 pg/mL; and plasma, 74.64 ± 43.94 pg/mL. There was a statistical difference between the study and the control group (P < 0.001) in the aqueous and vitreous samples. CONCLUSION: Stage 5 retinopathy of prematurity has elevated intraocular levels of vascular endothelial growth factor, which remains high despite severe retinal lesion. There was no statistical difference in plasma levels of the molecule between the control and study group.

Pattern scan laser photocoagulation: safety and complications, experience after 1301 consecutive cases.

BACKGROUND/AIMS: The pattern scan laser photocoagulator (PASCAL) is a novel laser device that uses 10-30 ms pulse duration for retina photocoagulation. The aim of this study was to analyse the safety profile of this approach. METHODS: This was a retrospective study. We reviewed the clinical records of all laser sessions performed with PASCAL from November 2007 to July 2008. Where there were any complications, we recorded the laser parameters, type, affected retina region, postoperative interval and treatment if required. RESULTS: There were 1301 consecutive cases. Complications included 17 cases of retinal bleeding (1.3%), two cases of choroidal detachment (0.15%) and one case of exudative retinal detachment (0.07%). There was no statistical difference between the laser parameters used in patients with or without complications. CONCLUSION: The laser parameters for PASCAL are safe. The complications and adverse effects encountered in this series are similar to those reported in other studies.

Reduction of fluence to decrease pain during panretinal photocoagulation in diabetic patients.

BACKGROUND AND OBJECTIVE: To assess the effect of laser fluence reduction to reduce pain during panretinal photocoagulation. PATIENTS AND METHODS: Twenty-five patients (50 eyes) with diabetic retinopathy who had indication for panretinal photocoagulation were included in this prospective, interventional, and comparative study. The right eyes were treated using low fluence parameters (LFP), whereas the left eyes were treated with standard fluence parameters (SFP). At the end of each session, the patient was asked to rate pain from 0 (no pain) to 10 (maximum pain) for each eye (NRS-11 scale). Fluence per burn and total fluence were determined for each eye. Statistical analysis was performed using the Mann-Whitney U test and the Pearson correlation coefficient. RESULTS: Pain perception (P < .01) and fluence per burn (P < .01) were significantly less using LFP compared with SFP. Pain was proportional to fluence per burn (R(2) = 0.4), but not to number of burns (R(2) = -0.2). CONCLUSION: The use of LFP seems to be a good option to diminish the pain during panretinal photocoagulation.

Pigment epithelium endoscopic laser surgery for treatment of choroidal neovascularization.

PURPOSE: To present a new concept and technique for subretinal surgery. METHODS: Twenty-four eyes of 24 patients with subfoveal choroidal neovascularization (CNV) were included in this study. Nine patients were operated on in Mexico City by one surgeon, 15 patients in Frankfurt by another surgeon. The retina at the posterior pole was detached and subretinal thermal photocoagulation of the CNVs was performed using a 20/19-gauge GRIN rod laser endoscope (Insight Instruments Inc., Sanford, Fla., USA). This procedure was termed PEELS (pigment epithelium endoscopic laser surgery). RESULTS: In 7 patients (Mexico), moderate improvement or stabilization of vision over 6 months or longer was achieved. In 10 out of 12 patients (Frankfurt), stabilization of vision over a follow-up period of 6-18 months was achieved, at least. Serious complications were not observed. Four of the Frankfurt series patients improved their vision. CONCLUSION: PEELS can stabilize or improve vision.

Terapia antiangiogénica ocular: experiencia clínica en México / Mexican clinical experience in ocular anti-angiogenic therapy

La angiogénesis patológica retiniana es la causa principal de pérdida visual en una gran cantidad de enfermedades: degeneración macular relacionada a la edad, retinopatía diabética y retinopatía del prematuro, en otras. Estas últimas dos son, además, problemas de salud pública en los países en desarrollo. Estudios recientes sobre la fisiopatología de estas enfermedades han demostrado el papel fundamental que los factores de crecimiento tienen sobre la angiogénesis. La terapia antiangiogénica ocular nació como un esfuerzo de inhibir la acción de estos factores sobre la angiogénesis patológica y preservar la visión. El objetivo de esta revisión es hacer un recuento de la experiencia en México en cuanto a esta modalidad terapéutica.

Retinal pathological angiogenesis is the leading cause of visual loss in a wide variety of ocular diseases. Some of the examples include: Age-related macular degeneration, diabetic retinopathy and retinopathy associated with prematurity. These last two entities are, in addition, public health problems in developing countries. Recent physiopathological studies, have demonstrated that growth factors play a key role on angiogenesis. Anti-angiogenic therapy came about as an attempt to inhibit the action of growth factors over the process of pathological angiogenesis in order to preserve vision. The objective of this review is to describe Mexico's experience using this therapeutic approach.

Toxicidad del perfluoro N-octano no purificado en ojos de conejo / Non-purified perfluoro N-octane toxicity in rabbit eyes

El Perfluoro-N-Octano(PFO) ha sido utilizado en ojos de pacientes humanos sin aparentes daños tóxicos a la retina. El propósito del presente estudio fue evaluar la toxicidad del PFO de uso no médico conocido como no purificado. A 14 conejos pigmentados se les realizó vitrectomía vía pars ciliaris en un ojo. La cavidad vítrea fue inyectada con PFO no purificado en 12 ojos y con solución salina balanceada se dejó a 2 ojos. En el grupo I permaneció en la cavidad vítrea el PFO durante 2 hrs después de la vitrectomía. En el grupo II durante 4 hrs y el grupo III con solución salina balanceada. A todos los conejos se les realizaron electrorretinogramas preoperatorios los cuales se repitieron a los 20, 40 y 60 días después de la cirugía. Todos los ojos fueron enucleados 60 días después de la inyección de PFO para examen histopatológico. Los resultados fueron los siguientes: El electrorretinograma mostró que todos los ojos con PFO tuvieron una disminución de la onda b en condiciones fotópicas y escotópicas; cambios que desaparecieron a los 20, 40 o 60 días después de la cirugía. El examen histopatológico mostró que los ojos tuvieron cambios en la capa plexiforme externa consistentes en adelgazamiento e interrupción en su continuidad, conos y bastones y demás estructuras sin alteraciones. Concluimos que el Perfluoro-N-Octano no purificado en ojos de conejo produce cambios reversibles en el electrorretinograma y alteraciones menores en la capa plexiforme externa sin alteración aparente de los fotorreceptores.

Prevalencia y gravedad de la retinopatía diabética en una población del Estado de Durango / Diabetic retinopathy prevalence and severity in a Durango State community

Se considera a la Diabetes Mellitus (DM) como uno de los principales problemas de salud, debido a su elevada prevalencia así como a la gravedad y variada morbilidad de que se acompaña. La Diabetes Mellitus es una de las principales causas de morbi-mortalidad en nuestro país. El objetivo del presente estudio es determinar la frecuencia y gravedad de la retinopatía diabética en una población del estado de Durango.Se estudió una población abierta en la ciudad de Durango seleccionándose pacientes con Diabetes Mellitus después de los 30 años (no insulino dependientes). Se les examinó para determinar la frecuencia y gravedad de la retinopatía diabética. Se estratificó la retinopatía diabética usando la clasificación del ETDRS (Early Treatment Diabetic Retinopathy Study, por sus siglas en inglés). Otras variables analizadas fueron edad, sexo y tiempo de evolución de la diabetes a partir del momento del diagnóstico.Se estudiaron 253 pacientes con diagnóstico de Diabetes Mellitus. La prevalencia de cualquier forma de retinopatía varió de 21.3 por ciento en personas con menos de cinco años de diagnóstico a 80.7 por ciento en aquellos con 15 o más años, estos resultados similares a reportes previos. La proporción de retinopatía diabética proliferativa varió de 1.6 por ciento en personas con cinco años o menos años de DM hasta 30.3 por ciento en aquéllos con más de 15 años.La prevalencia de las formas proliferativas de la enfermedad a cualquier tiempo del diagnóstico de DM fue más alta que en los informes previos. Los resultados sugieren que la retinopatía diabética proliferativa es más frecuente en México que en otros países.