Colágeno polivinilpirrolidona versus mitomicina C en trabeculectomía en pacientes con glaucoma primario de ángulo abierto. Seguimiento a 36 meses / Outcomes of trabeculectomy with polyvinylpyrrolidone collagen versus mitomycin in primary open angle glaucoma. 36-month follow-up

Propósito Describir y comparar los efectos de la aplicación intraoperatoria de colágeno polivinilpirrolidona (PVP) versus mitomicina C (MMC) en el patrón de cambio de la presión intraocular (PIO) y del número de medicamentos hipotensores utilizados en un seguimiento a 36 meses en pacientes con glaucoma primario de ángulo abierto (GPAA) operados de trabeculectomía. Métodos Estudio prospectivo, comparativo y aleatorizado. Veintiséis ojos de 26 pacientes con diagnóstico de GPAA, sin cirugías incisionales de glaucoma previas, fueron operados de trabeculectomía y aleatorizados a recibir PVP o MMC durante el procedimiento. Todos los pacientes cumplieron un seguimiento de 36 meses. Los resultados principales medidos fueron cambios en la PIO y el número de medicamentos hipotensores durante el seguimiento. Resultados El análisis multivariado reveló que la reducción de la PIO media del preoperatorio a los 36 meses de seguimiento fue de 7,62mmHg (3,05; 12,18) en el grupo de MMC y de 8,15mmHg (−0,64; 16,95) en el grupo de la PVP. La reducción media porcentual de la PIO fue del 37,09% (15,93; 58,17) en el grupo de MMC y del 36,08% (5,16; 67,20) en el grupo de la PVP. El cambio en el número de medicamentos del preoperatorio a los 36 meses de seguimiento fue de −0,92 medicamentos (-2,38; +1,54) para el grupo de MMC y de −1 medicamentos (−3,12, +1,12) para el grupo de la PVP. Ambos grupos tuvieron una disminución estadísticamente significativa de la PIO durante el seguimiento (p<0,001), pero no hubo una diferencia discernible entre los grupos (p=0,5975). El análisis de sensibilidad mostró que un modelo de tendencia lineal es adecuado para describir la reducción de la PIO durante el seguimiento. Ambos grupos tuvieron una reducción estadísticamente significativa de medicamentos del preoperatorio al final del seguimiento (p<0,05), tampoco hubo una diferencia discernible entre los grupos (p=0,2917)(AU)

Purpose Describe and compare the effects of intraoperative application of Polyvinylpyrrolidone Collagen (PVP) versus Mitomycin C (MMC) on the pattern of change in mean IOP reduction and mean number of medications over 36-months follow-up in patients with primary open angle glaucoma (POAG) undergoing trabeculectomy. Methods Prospective, randomized, comparative study. Twenty-six eyes of 26 patients with POAG and no previous incisional glaucoma surgery underwent trabeculectomy and were randomized to PVP or MMC and completed a 36-month follow-up. Main outcome measures were IOP and number of glaucoma medications. Multivariate longitudinal analysis was performed by fitting a linear trend model adjusting for baseline response for the IOP outcome and a log-linear regression model with within-subject associations for the number of hypotensive medications outcome. Sensitivity analysis was performed to assess lower and higher order polynomial trends over time in IOP. Results The univariate analysis revealed that the mean IOP reduction from baseline to 36 months was 7.62mmHg (3.05; 12.18) in the MMC group and 8.15mmHg (−0.64; 16.95) in the PVP group. Mean percentage IOP reduction from baseline was 37.09% (15.93; 58.17) and 36.08% (5.16; 67.20) in the PVP group. Mean change in number of medications from baseline to 36 months was −0.92 medications (−3.38; +1.54) for the MMC group and −1 medication (−3.12; +1.12) for the PVP group. Both groups had a statistically significant decline in mean IOP over the follow-up period (p<0.001) but there was no discernible difference between the two exposure groups in the rate of change in IOP (p=0.5975). Sensitivity analysis showed that a linear trend model is adequate to describe the IOP reduction over the follow-up period. Both groups had a statistically significant change in the number of hypotensive medications used between baseline and month 36 (p<0.05) but there was no discernible difference between exposure groups (p=0.2917) (AU)

Outcomes of trabeculectomy with polyvinylpyrrolidone collagen versus mitomycin in primary open angle glaucoma. 36-month follow-up. / Colágeno polivinilpirrolidona versus mitomicina C en trabeculectomía en pacientes con glaucoma primario de ángulo abierto. Seguimiento a 36 meses.

PURPOSE: Describe and compare the effects of intraoperative application of Polyvinylpyrrolidone Collagen (PVP) versus Mitomycin C (MMC) on the pattern of change in mean IOP reduction and mean number of medications over 36-months follow-up in patients with primary open angle glaucoma (POAG) undergoing trabeculectomy. METHODS: Prospective, randomized, comparative study. Twenty-six eyes of 26 patients with POAG and no previous incisional glaucoma surgery underwent trabeculectomy and were randomized to PVP or MMC and completed a 36-month follow-up. Main outcome measures were IOP and number of glaucoma medications. Multivariate longitudinal analysis was performed by fitting a linear trend model adjusting for baseline response for the IOP outcome and a log-linear regression model with within-subject associations for the number of hypotensive medications outcome. Sensitivity analysis was performed to assess lower and higher order polynomial trends over time in IOP. RESULTS: The univariate analysis revealed that the mean IOP reduction from baseline to 36 months was 7.62mmHg (3.05; 12.18) in the MMC group and 8.15mmHg (-0.64; 16.95) in the PVP group. Mean percentage IOP reduction from baseline was 37.09% (15.93; 58.17) and 36.08% (5.16; 67.20) in the PVP group. Mean change in number of medications from baseline to 36 months was -0.92 medications (-3.38; +1.54) for the MMC group and -1 medication (-3.12; +1.12) for the PVP group. Both groups had a statistically significant decline in mean IOP over the follow-up period (p<0.001) but there was no discernible difference between the two exposure groups in the rate of change in IOP (p=0.5975). Sensitivity analysis showed that a linear trend model is adequate to describe the IOP reduction over the follow-up period. Both groups had a statistically significant change in the number of hypotensive medications used between baseline and month 36 (p<0.05) but there was no discernible difference between exposure groups (p=0.2917). Both the PVP and MMC groups showed an initial reduction in number of medications until month 12 and a relatively linear increase towards month 36. A longer follow-up may be warranted to reveal differences in the number of medications between the two exposure groups. Postoperative complications were less frequent in the PVP group. CONCLUSIONS: The use of PVP during trabeculectomy achieves and maintains a statistically significant IOP reduction from baseline to 36 months and decreases the number of glaucoma medications. Secondary outcome measures showed a lower incidence of adverse events in the PVP group.

Estudio comparativo de la seguridad y eficacia entre el dispositivo valvular de Ahmed modelo M4 (polietileno poroso de alta densidad) y el modelo S2 (polipropileno) en pacientes con diagnóstico de glaucoma neovascular / Comparative study of the safety and efficacy of the Ahmed glaucoma valve model M4 (high density porous polyethylene) and the model S2 (polypropylene) in patients with neovascular glaucoma

OBJETIVO: El objetivo de este estudio fue evaluar de forma prospectiva la seguridad y eficacia del dispositivo valvulado de Ahmed modelo M4 (sistema valvular convencional en plato de polietileno poroso de alta densidad, Medpor) comparado con el modelo S2 (plato de polipropileno). MÉTODO: Se formaron 2 grupos de pacientes con glaucoma neovascular. Un grupo en el que se implantó el dispositivo M4 y el grupo en el que se implantó el dispositivo S2. En ambos grupos (M4 y S2) se incluyó a pacientes mestizos mexicanos. Dichos pacientes fueron intervenidos quirúrgicamente, utilizando la técnica convencional consistente en la fijación escleral del cuerpo valvular en el cuadrante temporal superior a 8mm del limbo y realizando un túnel subepiescleral para colocar el tubo del dispositivo dentro de la cámara anterior, de acuerdo con la técnica descrita por nuestro grupo en forma previa. Después de un año de seguimiento los resultados fueron evaluados tomando en cuenta la reducción de la presión intraocular (PIO), los cambios en la agudeza visual, el uso de hipotensores oculares complementarios y las complicaciones aparecidas, así como las características demográficas de cada grupo. En el caso del modelo M4, los procedimientos quirúrgicos fueron realizados por el mismo cirujano (FGC). Los pacientes en los que se implantó el modelo S2 fueron operados por diversos cirujanos, incluyendo a FGC, del Servicio de Glaucoma del Hospital Dr. Luis Sánchez Bulnes de la Asociación para Evitar la Ceguera en México (APEC). RESULTADOS: En cada uno de los 2 grupos se operaron 21 ojos de 21 pacientes con diagnóstico de glaucoma neovascular, conformando los 42 ojos incluidos en este estudio. La PIO promedio en el preoperatorio fue de 43,5mmHg (±11,8) para el grupo de M4 y de 42,24mmHg (±12,84) para el grupo de S2. Después de un año de seguimiento, la PIO reportada fue 18,9mmHg (±9,7) para el grupo de M4 y 16,38mmHg (±9,76) para el grupo de S2. CONCLUSIONES: Creemos que es necesario efectuar un mayor número de estudios a largo plazo con un número mayor de pacientes, para poder evaluar la ayuda de esta cubierta porosa en el control tensional de los pacientes con el diagnóstico de GNV

OBJECTIVE: To prospectively evaluate the safety and efficacy of the Ahmed glaucoma valve model M4 (High density porous polyethylene plate; Medpor) compared with the model S2 (polypropylene plate). METHOD: Mexican patients with neovascular glaucoma were randomly included for each group (M4 and S2). They were operated on using conventional techniques and creating a sub-episcleral tunnel to place the valve tube in the anterior chamber. After one year of follow-up, the results were evaluated with respect to a post-operative reduction in pressure, changes in visual acuity, the need for drugs, and complications, as well as the demographic characteristics of each group. Each operation using the M4 valve was performed by a single surgeon (FGC). Those operated on using the S2 model had their surgery performed by the staff surgeons at the Glaucoma Department of the Mexican Association to Prevent Blindness (APEC). RESULTS: Each group (M4 and S2) contained 21 eyes of 21 Mexican patients with a diagnosis of neovascular glaucoma, leading to a total of 42 patients undergoing surgery. The mean preoperative intraocular pressure (IOP) was 43.5 (±11.8), and 42.24 (±12.84) mmHg for the M4 and S2 groups, respectively. After one year of follow-up, the IOP reported was 18.9 (±9.7) mmHg for the final 18 patients in the M4 group, and 16.38 (±9.76) mmHg for the 21 patients in the S2 group. DISCUSSION: The design of a drainage valve device such as that of Ahmed has characteristics such as moderate control of IOP, thanks to the valve component in the immediate post-operative period, which makes them safer than other non-valve devices. This avoids an excess of flat chambers and the presence of low IOPs, which can lead to bleeding in the early post-operative period due to the weak desmosomal junctions of the newly formed vessels, with the advantage of maintaining suitable control of IOP from the first day after surgery. CONCLUSION: Further studies with longer follow-up with a larger number of patients are needed to evaluate the effectiveness of this porous coating in the control of neovascular glaucoma

Comparative study of the safety and efficacy of the Ahmed glaucoma valve model M4 (high density porous polyethylene) and the model S2 (polypropylene) in patients with neovascular glaucoma. / Estudio comparativo de la seguridad y eficacia entre el dispositivo valvular de Ahmed modelo M4 (polietileno poroso de alta densidad) y el modelo S2 (polipropileno) en pacientes con diagnóstico de glaucoma neovascular.

OBJECTIVE: To prospectively evaluate the safety and efficacy of the Ahmed glaucoma valve model M4 (High density porous polyethylene plate; Medpor) compared with the model S2 (polypropylene plate). METHOD: Mexican patients with neovascular glaucoma were randomly included for each group (M4 and S2). They were operated on using conventional techniques and creating a sub-episcleral tunnel to place the valve tube in the anterior chamber. After one year of follow-up, the results were evaluated with respect to a post-operative reduction in pressure, changes in visual acuity, the need for drugs, and complications, as well as the demographic characteristics of each group. Each operation using the M4 valve was performed by a single surgeon (FGC). Those operated on using the S2 model had their surgery performed by the staff surgeons at the Glaucoma Department of the Mexican Association to Prevent Blindness (APEC). RESULTS: Each group (M4 and S2) contained 21 eyes of 21 Mexican patients with a diagnosis of neovascular glaucoma, leading to a total of 42 patients undergoing surgery. The mean preoperative intraocular pressure (IOP) was 43.5 (±11.8), and 42.24 (±12.84) mmHg for the M4 and S2 groups, respectively. After one year of follow-up, the IOP reported was 18.9 (±9.7) mmHg for the final 18 patients in the M4 group, and 16.38 (±9.76) mmHg for the 21 patients in the S2 group. DISCUSSION: The design of a drainage valve device such as that of Ahmed has characteristics such as moderate control of IOP, thanks to the valve component in the immediate post-operative period, which makes them safer than other non-valve devices. This avoids an excess of flat chambers and the presence of low IOPs, which can lead to bleeding in the early post-operative period due to the weak desmosomal junctions of the newly formed vessels, with the advantage of maintaining suitable control of IOP from the first day after surgery. CONCLUSION: Further studies with longer follow-up with a larger number of patients are needed to evaluate the effectiveness of this porous coating in the control of neovascular glaucoma.

Switching prostaglandin analogues and 24-hour IOP fluctuations.

OBJECTIVES: To evaluate the fluctuations in 24h mean intraocular pressure (IOP) when switching prostaglandin analogues in patients with glaucoma. METHODS: Fourteen patients with primary open angle glaucoma were evaluated with monthly 24-hour IOP curves, using a monthly switching pattern of prostaglandin analogues and brinzolamide during 3 years of follow-up. RESULTS: Average IOP and average fluctuation (peak to through difference) were significantly higher with brinzolamide than with any of the analogues. There was no significant difference in either parameter with the different prostaglandin analogues, regardless of the order in which they were evaluated, or even if a month on brinzolamide was intercalated between the analogues. CONCLUSIONS: Brinzolamide was less effective than prostaglandin analogues in reducing 24-hour mean IOP and its fluctuations. Switching analogues had no significant effect on mean IOP or mean IOP fluctuations.

Rotación de análogos de prostaglandinas y fluctuaciones diurnas de la presión intraocular / Switching prostaglandin analogues and 24-hour iop fluctuations

Objetivos: Evaluar la eficacia de la rotación de análogos de prostaglandinas sobre las fluctuaciones de la presión intraocular (PIO) en 24h. Métodos: Se evaluó a 14 pacientes con glaucoma primario de ángulo abierto mediante curvas mensuales de presión intraocular de 24h, realizando un patrón de cambios mensuales del tratamiento hipotensor entre brinzolamida y análogos de prostaglandinas durante un período de tres años. Resultados: Tanto el promedio de PIO como el promedio de variación (diferencia entre el pico y el valle) durante las curvas fueron significativamente mayores con la brinzolamida que con cualquiera de los tres análogos. Tanto el promedio de PIO como el promedio de fluctuaciones fueron similares entre los tres análogos, independiente del orden en que se usaron o de si se intercaló un mes de brinzolamida entre uno y otro análogo. Conclusiones: La brinzolamida fue menos efectiva para reducir la PIO promedio y sus fluctuaciones durante 24h. No hubo un cambio significativo al rotar los análogos(AU)

Objectives: To evaluate the fluctuations in 24h mean intraocular pressure (IOP) when switching prostaglandin analogues in patients with glaucoma. Methods: Fourteen patients with primary open angle glaucoma were evaluated with monthly 24-hour IOP curves, using a monthly switching pattern of prostaglandin analogues and brinzolamide during 3 years of follow-up. Results: Average IOP and average fluctuation (peak to through difference) were significantly higher with brinzolamide than with any of the analogues. There was no significant difference in either parameter with the different prostaglandin analogues, regardless of the order in which they were evaluated, or even if a month on brinzolamide was intercalated between the analogues. Conclusions: Brinzolamide was less effective than prostaglandin analogues in reducing 24-hour mean IOP and its fluctuations. Switching analogues had no significant effect on mean IOP or mean IOP fluctuations(AU)

Comparison of Goldmann applanation and dynamic contour tonometry in a population of Mexican open-angle glaucoma patients.

To compare intraocular pressure (IOP) measurements obtained with Goldmann applanation (GAT) and dynamic contour tonometry (DCT) in a Mexican population. 40 glaucoma patients were included in this cross-sectional observational cohort study. IOP measurements were performed in the following order: DCT, ultrasonic pachymetry and GAT, with a 5-minute difference between each measurement, between 8 am and 2 pm. Only DCT measurements of good quality (Q ≤ 3) were accepted. GAT measurements were made three times with the same Goldmann tonometer, previously checked for calibration errors, and the mean was used for statistical purposes. The IOP (mean [standard deviation], 95 % confidence interval [CI]) measured with the Goldmann tonometer (13.2 [2.4], 12.4-14.0 mmHg) was significantly lower than that obtained with the DCT (18.4 [3.3], 17.0-19.2 mmHg), p < 0.0001. Pearson's correlation coefficients between CCT and IOP measured with GAT and DCT were (r = 0.24, 95 % CI = 0.07-0.52, p = 0.133) and (r = 0.13, 95 % CI = -0.19 to 0.43, p = 0.412), respectively. The concordance correlation coefficient between GAT and DCT was r c = 0.3, 95 % CI = 0.17-0.41). DCT seems to overestimate the IOP as compared to GAT. Additionally, although there was a good correlation between the IOP measurements assessed with either GAT or DCT, the agreement was poor.

HLA-DRB and HLA-DQB loci in the genetic susceptibility to develop glaucoma in Mexicans.

PURPOSE: Glaucoma is a clinically heterogeneous disease with a pathophysiology that may include genetic susceptibility, possibly associated with an immunologic disorder. The aim of this study was to determine whether the DNA polymorphisms located in the HLA-DRB1 and HLA-DQB1 genes show a specific association pattern in Mexican mestizo patients with primary open-angle glaucoma. METHODS: This was a cross-sectional, case-control, multicenter study. We analyzed the HLA-DRB1 and DQB1 loci of 81 Mexican mestizo nonrelated patients with primary open-angle glaucoma and 98 healthy ethnic matched control subjects. Patients were diagnosed clinically and by visual fields examination. HLA typing was performed by PCR-SSO reverse dot blot. RESULTS: We documented increased frequencies of HLA-DRB1*0301, DRB1*1101, DRB1*0701, DRB1*1402, DQB1*0302, and DQB1*0301; however, none of them were significantly different from normal control subjects. Haplotype analysis showed that the HLA-DRB1*0407-DQB1*0302 haplotype is significantly increased in patients compared with control subjects (P = .0001). CONCLUSIONS: The haplotype HLA-DRB1*0407-DQB1*0302 is common among Mexican mestizo (haplotype frequency = 0.102), and it was increased in our patients (haplotype frequency = 0.259, P = .0001). This may reflect an independent association of this haplotype with the disease as the result of linkage disequilibrium or the influence of a neighboring gene. The pathophysiology of this illness is uncertain, and further studies are needed regarding the genetic susceptibility to develop primary open-angle glaucoma.

Ahmed valve implant for uncontrolled uveitic glaucoma.

To evaluate the efficacy of the Ahmed valve implant in patients with uncontrolled uveitic glaucoma, the medical records of all patients with uncontrolled uveitic glaucoma who underwent Ahmed valve implant surgery between October 1993 and March 1996 were reviewed. Surgery was considered a success if intraocular pressure (IOP) was less than 22 mmHg and greater than 4 mmHg (with or without antiglaucoma medications) at the last postoperative visit. It was not a success when further glaucoma surgery had been performed, or chronic hypotony, phthisis, or loss of light perception occurred. Fourteen patients (14 eyes) with a mean age of 45.7 years were included. Most of them were high-risk patients, many of whom had already had cataract surgery (71.4%) and undergone one to three previous glaucoma surgeries (57.1%). Follow-up for eyes in which IOP was controlled ranged from 11 to 40 months (mean 22.6 months). Success was achieved in eight of 14 eyes (57.14%). Intraocular pressure was reduced from a mean of 32.64 +/- 7.79 mmHg (range 23-46 mmHg) with 2.78 +/- 0.57 antiglaucoma medications (range 2-4) preoperatively to 17.57 +/- 10.93 mmHg (range 0-38 mmHg) (p < 0.0001) with 0.71 +/- 0.99 antiglaucoma medications (range 0-3) postoperatively (p < 0.0001). The most common complications were encapsulated bleb in six eyes (42.8%), transient hypotony in six eyes (42.8%), and hyphema in three (21.4%). Ahmed valve implant appeared to be a safe alternative in high-risk patients with uncontrolled uveitic glaucoma who have had multiple previous ocular surgeries.

Immunogenetic aspects in primary open-angle glaucoma in family members of Mexican mestizo glaucomatous patients.

We determined antigens of the major histocompatibility complex classes I, II, and III in 25 families of Mexican mestizo glaucomatous patients. Patients and family members were examined, and the predisposition of first-degree relatives to a corticosteroid-provocative test was determined. The results showed a high frequency of the HLA-DR3 antigen in patients with primary open-angle glaucoma compared with controls (32.5% vs 4.0%, P = .001, odds ratio = 10.25). We suggest that the increased presence of the HLA-DR3 antigen could be an important factor in the genetic susceptibility to glaucoma.