Using advanced analysis of multifocal visual-evoked potentials to evaluate the risk of clinical progression in patients with radiologically isolated syndrome.

This study aimed to assess the role of multifocal visual-evoked potentials (mfVEPs) as a guiding factor for clinical conversion of radiologically isolated syndrome (RIS). We longitudinally followed a cohort of 15 patients diagnosed with RIS. All subjects underwent thorough ophthalmological, neurological and imaging examinations. The mfVEP signals were analysed to obtain features in the time domain (SNRmin: amplitude, Latmax: monocular latency) and in the continuous wavelet transform (CWT) domain (bmax: instant in which the CWT function maximum appears, Nmax: number of CWT function maximums). The best features were used as inputs to a RUSBoost boosting-based sampling algorithm to improve the mfVEP diagnostic performance. Five of the 15 patients developed an objective clinical symptom consistent with an inflammatory demyelinating central nervous system syndrome during follow-up (mean time: 13.40 months). The (SNRmin) variable decreased significantly in the group that converted (2.74 ± 0.92 vs. 4.07 ± 0.95, p = 0.01). Similarly, the (bmax) feature increased significantly in RIS patients who converted (169.44 ± 24.81 vs. 139.03 ± 11.95 (ms), p = 0.02). The area under the curve analysis produced SNRmin and bmax values of 0.92 and 0.88, respectively. These results provide a set of new mfVEP features that can be potentially useful for predicting prognosis in RIS patients.

Filtering multifocal VEP signals using Prony's method.

BACKGROUND: This paper describes use of Prony's method as a filter applied to multifocal visual-evoked-potential (mfVEP) signals. Prony's method can be viewed as an extension of Fourier analysis that allows a signal to be decomposed into a linear combination of functions with different amplitudes, damping factors, frequencies and phase angles. METHOD: By selecting Prony method parameters, a frequency filter has been developed which improves signal-to-noise ratio (SNR). Three different criteria were applied to data recorded from control subjects to produce three separate datasets: unfiltered raw data, data filtered using the traditional method (fast Fourier transform: FFT), and data filtered using Prony's method. RESULTS: Filtering using Prony's method improved the signals' original SNR by 44.52%, while the FFT filter improved the SNR by 33.56%. The extent to which signal can be separated from noise was analysed using receiver-operating-characteristic (ROC) curves. The area under the curve (AUC) was greater in the signals filtered using Prony's method than in the original signals or in those filtered using the FFT. CONCLUSION: filtering using Prony's method improves the quality of mfVEP signal pre-processing when compared with the original signals, or with those filtered using the FFT.

Improved measurement of intersession latency in mfVEPs.

PURPOSE: The purpose of the study is to present a method (Selfcorr) by which to measure intersession latency differences between multifocal VEP (mfVEP) signals. METHODS: The authors compared the intersession latency difference obtained using a correlation method (Selfcorr) against that obtained using a Template method. While the Template method cross-correlates the subject's signals with a reference database, the Selfcorr method cross-correlates traces across subsequent recordings taken from the same subject. RESULTS: The variation in latency between intersession signals was 0.8 ± 13.6 and 0.5 ± 5.0 ms for the Template and Selfcorr methods, respectively, with a coefficient of variability CV_TEMPLATE = 15.83 and CV_SELFCORR = 5.68 (n = 18, p = 0.0002, Wilcoxon). The number of analyzable sectors with the Template and Selfcorr methods was 36.7 ± 8.5 and 45.3 ± 8.7, respectively (p = 0.0001, paired t test, two tailed). CONCLUSIONS: The Selfcorr method produces smaller intersession mfVEP delays and variability over time than the Template method.

Effects of pterygium on the biomechanical properties of the cornea: a pilot study.

OBJECTIVE: To investigate the changes induced by a pterygium or its surgical removal on the biomechanical properties of the cornea and to determine factors that might affect these parameters. METHODS: This prospective pilot interventional, non-randomized, observer-masked study included 20 eyes of 20 patients with a unilateral primary pterygium (pterygium group) and 19 fellow healthy eyes (control group). The bare sclera technique with one-minute application of 0.02% mitomycin C intraoperatively was performed in all cases. The follow-up period was one month. The preoperative and postoperative biomechanical properties of the cornea were measured using the Reichert ocular response analyzer (ORA). RESULTS: The corneal hysteresis (CH) decreased significantly (P<.01) in eyes with a pterygium compared to the control eyes, while surgery did not significantly change the CH compared to preoperatively. There were no significant changes in the corneal resistance factor or the central corneal thickness. CONCLUSIONS: Primary active pterygium (grades 1 or 2) induce a reduction of corneal biomechanical features. Further studies are needed in populations, with longer follow-ups and bigger pterygium that may involve wider keratectomy to confirm our results.

Efecto del pterigión en las propiedades biomecánicas de la córnea: estudio piloto / Effects of pterygium on the biomechanical properties of the cornea: a pilot study

Objetivo: Investigar los cambios inducidos en la biomecánica de la córnea por la presencia de pterigión o por su exéresis quirúrgica, así como determinar los factores que influyen sobre dichos parámetros. Métodos: Estudio piloto, intervencional y prospectivo, con observador enmascarado que incluía 20 ojos de 20 pacientes con pterigión primario unilateral (grupo pterigión) y 19 ojos adelfos sanos (grupo control). Se realizó una resección simple del pterigión con aplicación intraoperatoria de mitomicina C 0,02% durante un minuto sobre el lecho escleral. El periodo de seguimiento fue de un mes. Las propiedades biomecánicas de la córnea fueron determinadas preoperatoria y postoperatoriamente mediante el analizador de respuesta ocular Reichert (ORA). Resultados: La presencia de pterigión disminuyó significativamente la histéresis corneal (HC) en comparación con el grupo control (p<0,01). No encontramos diferencias estadísticamente significativas entre las medidas pre- y postoperatorias de la HC, del factor de resistencia corneal, ni del espesor corneal central. Conclusión: La presencia de un pterigión primario activo (grados 1 y 2) conduce a una reducción de las propiedades biomecánicas de la córnea. Serían necesarios nuevos estudios con un mayor tiempo de seguimiento y pterigiones más avanzados, con queratectomías más amplias para confirmar estos efectos(AU)

Objective: To investigate the changes induced by a pterygium or its surgical removal on the biomechanical properties of the cornea and to determine factors that might affect these parameters. Methods: This prospective pilot interventional, non-randomized, observer-masked study included 20 eyes of 20 patients with a unilateral primary pterygium (pterygium group) and 19 fellow healthy eyes (control group). The bare sclera technique with one-minute application of 0.02% mitomycin C intraoperatively was performed in all cases. The follow-up period was one month. The preoperative and postoperative biomechanical properties of the cornea were measured using the Reichert ocular response analyzer (ORA). Results: The corneal hysteresis (CH) decreased significantly (P<0.01) in eyes with a pterygium compared to the control eyes, while surgery did not significantly change the CH compared to preoperatively. There were no significant changes in the corneal resistance factor or the central corneal thickness. Conclusions: Primary active pterygium (grades 1 or 2) induce a reduction of corneal biomechanical features. Further studies are needed in populations, with longer follow-ups and bigger pterygium that may involve wider keratectomy to confirm our results(AU)

[Short-tau inversion-recovery (STIR) sequence magnetic resonance imaging evaluation of orbital structures in Graves' orbitopathy]. / Evaluación de la órbita mediante secuencias short-tau inversion-recovery (STIR) en resonancia nuclear magnética en la orbitopatía de Graves.

OBJECTIVE: To evaluate the orbital structures and to establish correlations with disease activity and severity in patients with Graves' hyperthyroidism and orbitopathy (GO) using short-tau inversion-recovery (STIR) sequence magnetic resonance imaging (MRI). METHODS: Observational, cross-sectional, case-control study. Twenty-eight patients with euthyroid status after treatment and GO (GO group) and 15 control subjects (control group) were included. Patients underwent a complete ophthalmologic examination and were then assessed according to the EUGOGO (European Group on Graves' Orbitopathy) recommendations. Muscle cross-sectional areas, orbital tissue volumes and the signal intensity ratio (SIR) from the most inflamed extraocular muscle were calculated using a STIR-T2 weighted sequence MRI. Correlations between clinical and MRI measurements were analyzed. RESULTS: Enlargements in the cross-sectional areas and volumes were significant for most EOMs (P<.001), but not for the lateral rectus muscle cross-sectional area. A significant difference in SIR values between patients with GO and control subjects (P<.001) was found. No significant correlations were found between muscle cross-sectional areas, orbital tissue volumes, SIR values and the clinical activity parameters. CONCLUSIONS: Given the small sample size of our study, with the obvious need for larger clinical trials, we were unable to demonstrate that the STIR sequences in MRI are a sensitive tool in assessing patients with longstanding GO in order to detect inflammatory changes and activity follow-up, possibly because it is in inactive phase. Meanwhile, it is still necessary to continue performing a thorough clinical evaluation in the therapeutic management of GO.

[Effectiveness of topical bevacizumab in bilateral primary lipid keratopathy]. / Eficacia de bevacizumab tópico en queratopatía lipoidea bilateral primaria.

CASE REPORT: A 75-year-old man with bilateral idiopathic lipid keratopathy underwent a penetrating keratoplasty in the left eye. One month later, there was deep corneal neovascularisation extending across the bed and the graft-host interface, with a whitish opacity surrounding the vessels. Topical bevacizumab (25mg/mL) was administered 4 times daily for 2 months with partial regression of corneal neovascularization. DISCUSSION: Topical bevacizumab may be useful in preventing a recurrence of lipid deposition after penetrating keratoplasty in patients with bilateral primary lipid keratopathy, although its long-term efficacy needs to be assessed.

Evaluación de la órbita mediante secuencias short-tau inversion-recovery (STIR) en resonancia nuclear magnética en la orbitopatía de Graves / Short-tau inversion-recovery (STIR) sequence magnetic resonance imaging evaluation of orbital structures in Graves’ orbitopathy

Objetivo: Evaluar las estructuras orbitarias mediante secuencias short-tau inversion-recovery (STIR) en resonancia nuclear magnética (RNM) y establecer correlaciones con los signos de actividad clínica (CAS) y severidad en pacientes con hipertiroidismo y orbitopatía Graves (OG). Métodos: Estudio clínico de casos y controles, observacional y transversal. Veintiocho pacientes en estatus eutiroideo postratamiento y OG (grupo OG) y 15 sujetos controles (grupo control) fueron evaluados. Se realizó una exploración oftalmológica completa a los participantes y se determinó la actividad y severidad de la OG, según recomendaciones EUGOGO (Grupo Europeo en Orbitopatía Graves). Áreas de sección transversal de los músculos extraoculares (MOE), volúmenes de los tejidos orbitarios y ratios (SIR) de intensidad de señal del MOE más inflamado fueron calculados usando secuencias STIR-T2 en RNM. Se establecieron correlaciones entre variables. Resultados: Los incrementos en las áreas de sección transversal y volúmenes fueron significativos en la mayoría de los MOE (p<0,001), pero no en el área de sección transversal del recto lateral. Se encontraron diferencias significativas en valores SIR entre ambos grupos (p<0,001). No se establecieron correlaciones significativas entre el área total de sección transversal de los MOE, volúmenes de los tejidos orbitarios, valores SIR y signos de actividad clínica. Conclusiones: Dado el tamaño muestral del estudio, con la necesidad obvia de estudios más amplios, no podemos demostrar que las secuencias STIR en RNM sean una herramienta sensible para evaluar cambios inflamatorios y actividad clínica en la OG de larga evolución, posiblemente debido a que se halle en fase inactiva(AU)

Objective: To evaluate the orbital structures and to establish correlations with disease activity and severity in patients with Graves’ hyperthyroidism and orbitopathy (GO) using short-tau inversion-recovery (STIR) sequence magnetic resonance imaging (MRI). Methods: Observational, cross-sectional, case-control study. Twenty-eight patients with euthyroid status after treatment and GO (GO group) and 15 control subjects (control group) were included. Patients underwent a complete ophthalmologic examination and were then assessed according to the EUGOGO (European Group on Graves’ Orbitopathy) recommendations. Muscle cross-sectional areas, orbital tissue volumes and the signal intensity ratio (SIR) from the most inflamed extraocular muscle were calculated using a STIR-T2 weighted sequence MRI. Correlations between clinical and MRI measurements were analyzed. Results: Enlargements in the cross-sectional areas and volumes were significant for most EOMs (P<.001), but not for the lateral rectus muscle cross-sectional area. A significant difference in SIR values between patients with GO and control subjects (P<.001) was found. No significant correlations were found between muscle cross-sectional areas, orbital tissue volumes, SIR values and the clinical activity parameters. Conclusions: Given the small sample size of our study, with the obvious need for larger clinical trials, we were unable to demonstrate that the STIR sequences in MRI are a sensitive tool in assessing patients with longstanding GO in order to detect inflammatory changes and activity follow-up, possibly because it is in inactive phase. Meanwhile, it is still necessary to continue performing a thorough clinical evaluation in the therapeutic management of GO(AU)

Eficacia de bevacizumab tópico en queratopatía lipoidea bilateral primaria / Effectiveness of topical bevacizumab in bilateral primary lipid keratopathy

Caso clínico: Varón de 75 años con queratopatía lipoidea bilateral primaria. Es intervenido de queratoplastia penetrante en ojo izquierdo. Al mes se observa neovascularización corneal profunda extendiéndose sobre el lecho y la interfase injerto-huésped, con opacidad blanquecina alrededor de los neovasos. Se inicia tratamiento con bevacizumab tópico (25mg/mL) 4 veces/día durante 2 meses, con regresión parcial de la neovascularización corneal. Discusión: Bevacizumab tópico puede ser útil en la prevención de la recidiva de la queratopatía lipoidea tras queratoplastia penetrante en pacientes con queratopatía lipoidea bilateral primaria, aunque sería conveniente determinar su eficacia a largo plazo(AU)

Case report: A 75-year-old man with bilateral idiopathic lipid keratopathy underwent a penetrating keratoplasty in the left eye. One month later, there was deep corneal neovascularisation extending across the bed and the graft-host interface, with a whitish opacity surrounding the vessels. Topical bevacizumab (25mg/mL) was administered 4 times daily for 2 months with partial regression of corneal neovascularization. Discussion: Topical bevacizumab may be useful in preventing a recurrence of lipid deposition after penetrating keratoplasty in patients with bilateral primary lipid keratopathy, although its long-term efficacy needs to be assessed(AU)

[Morphometric analysis of corneal endothelium after intravitreal ranibizumab (Lucentis) in age-related macular degeneration treatment]. / Análisis morfométrico del endotelio corneal tras ranibizumab intravítreo en la degeneración macular asociada a la edad.

PURPOSE: To determine the effect of intravitreal injection of 0.5mg ranibizumab on the corneal endothelium in patients with age-related macular degeneration (AMD). METHODS: Observational, prospective case series pilot study. Twenty-six eyes of 26 consecutive patients with AMD were evaluated. All participants received one monthly intravitreal injections of 0.5mg ranibizumab for three consecutive months. The follow-up period was 6 months. Central corneal specular microscopy was performed before injection and at 7 days and 6 months after the first intravitreal injection. The endothelial cell density, coefficient of variation of cell size, and percentage of hexagonal cells were analyzed and the central corneal thickness was measured. RESULTS: There were no significant differences in the endothelial cell densities, coefficients of variation of cell size and percentages of hexagonal cells before injection and at 7 days and 6 months after the first intravitreal ranibizumab injection (P>0.5). There was also no significant difference in central corneal thickness measurements through the follow-up period (P>0.5). CONCLUSIONS: Repeated intravitreal injections of 0.5mg ranibizumab do not seem to cause substantial changes in the corneal endothelium.

Expresión de marcadores embrionarios en células mesenquimales de pterygium / Expression of embryonic markers in pterygium derived mesenchymal cells

Propósto: La destrucción de la barrera del epitelio limbal es el mecanismo más importante en la formación del pterygium. Se piensa que proviene de la activación y proliferación de células madre (stem cells) del epitelio limbal. El objetivo de este estudio ha sido determinar la presencia de células mesenquimíticas indiferenciadas (stem cells) en cultivos celulares obtenidos de pterygium humano. Métodos: Las células de 6 pterygium humanos fueron aisladas mediante explantos y cultivadas en amniomax. Al alcanzar la confluencia, las células fueron sembradas en microplacas de 24 pocillos. Los cultivos celulares fueron estudiados en el 2.¡- subcultivo. Se analizá mediante inmunofluorescencia la expresión de los marcadores de células madre embrionarias, OCT3/4 y CD9. Los diferentes fenotipos celulares fueron caracterizados con los anticuerpos monoclonales anti-CD31, Á-actina y vimentina. Resultados: Toda la población celular obtenida de pterygium muestra expresión para vimentina. Menos de un 1% de las células presentaron expresión para los marcadores CD31 y Á-actina. La mayor parte de la población celular fue positiva para los marcadores embrionarios OCT3/4 y CD9. Conclusión: La población celular expandida a partir de pterygium está compuesta por células de fenotipo mesenquimal, que muestran expresión de marcadores embrionarios OCT3/4 y CD9. Esta población, con un alto grado de indiferenciación, podrá ser responsable de la alta tasa de recurrencia del pterygium tras su extirpación quirurgica (AU)

BackgroundDestruction of the limbal epithelium barrier is the most important mechanism of pterygium formation (conjunctiva proliferation, encroaching onto the cornea). It is thought to arise from activated and proliferating limbal epithelial stem cells. The objective of this study is to evaluate the presence of undifferentiated mesenchymal cells (stem cells) in cultured cells extracted from human pterygium.Material and methodsCells from 6 human pterygium were isolated by explantation and placed in cultures with amniomax medium. Once the monolayer was reached the cells were seeded onto 24 well microplates. The cells were studied in the second sub-culture. The immunohistochemical expression of different embryonic stem cell markers, OCT3/4 and CD9, was analysed. The differentiated phenotypes were characterised with the monoclonal antibodies anti-CD31, ¦Á-actin and vimentin.ResultsAll the cell populations obtained from pterygium showed vimentin expression. Less than 1% of the cells were positive for CD31 and ¦Á-actin markers. The majority of the cell population was positive for OCT3/4 and CD9.ConclusionsThe cell population obtained from pterygium expressed mesenchymal cell phenotype and embryonic markers, such us OCT3/4 and CD9. This undifferentiated population could be involved in the large recurrence rate of this type of tissue after surgery(AU)

Análisis morfométrico del endotelio corneal tras ranibizumab intravítreo en la degeneración macular asociada a la edad / Morphometric analysis of corneal endothelium after intravitreal ranibizumab (Lucentis®) in age-related macular degeneration treatment

ObjetivoEvaluar el efecto de la inyección intravítrea de 0,5mg ranibizumab sobre el endotelio corneal en pacientes con degeneración macular asociada a la edad (DMAE).MétodoEstudio piloto de serie de casos, observacional y prospectivo con observador enmascarado. Veintiséis ojos (26 pacientes) con DMAE fueron evaluados. Todos los pacientes recibieron 1 inyección intravítrea mensual de 0,5mg de ranibizumab durante 3 meses consecutivos. El periodo de seguimiento fue de 6 meses. El endotelio corneal central fue evaluado antes, a los 7 días y a los 6 meses de la primera inyección de ranibizumab con microscopía especular. La densidad de las células endoteliales, coeficiente de variación del tamaño celular y porcentaje de hexagonalidad celular fueron analizados. También fue medido el espesor corneal central.ResultadosNo se encontraron diferencias estadísticamente significativas entre los valores preinyección y postinyección a los 7 días y 6 meses de la primera inyección de ranibizumab en las densidades de células endoteliales, coeficientes de variación del tamaño celular y porcentajes de hexagonalidad celular (p>0,5). Tampoco se encontraron modificaciones significativas en el espesor corneal central a lo largo del periodo de seguimiento (p>0,5).ConclusionesInyecciones intravítreas repetidas de 0,5mg ranibizumab no parecen causar cambios importantes sobre el endotelio corneal a los 6 meses de seguimiento(AU)

PurposeTo determine the effect of intravitreal injection of 0.5mg ranibizumab on the corneal endothelium in patients with age-related macular degeneration (AMD).MethodsObservational, prospective case series pilot study. Twenty-six eyes of 26 consecutive patients with AMD were evaluated. All participants received one monthly intravitreal injections of 0.5mg ranibizumab for three consecutive months. The follow-up period was 6 months. Central corneal specular microscopy was performed before injection and at 7 days and 6 months after the first intravitreal injection. The endothelial cell density, coefficient of variation of cell size, and percentage of hexagonal cells were analyzed and the central corneal thickness was measured.ResultsThere were no significant differences in the endothelial cell densities, coefficients of variation of cell size and percentages of hexagonal cells before injection and at 7 days and 6 months after the first intravitreal ranibizumab injection (P>0.5). There was also no significant difference in central corneal thickness measurements through the follow-up period (P>0.5).ConclusionsRepeated intravitreal injections of 0.5mg ranibizumab do not seem to cause substantial changes in the corneal endothelium(AU)

[Endothelial cells analysis after intraoperative mitomycin-C adjuvant pterygium simple excision surgery: a pilot study]. / Análisis morfométrico del endotelio de la córnea tras aplicación intraoperatoria de mitomicina C en la resección simple de pterigión: un estudio piloto.

PURPOSE: To study the effects of mitomycin-C (MMC) on the corneal endothelium after pterygium surgery. METHODS: Prospective, interventional, nonrandomized, observer-masked study. Twenty patients (20 eyes) with primary pterygium underwent surgery with pterygium simple excision followed by 0.02% MMC application for 1 minute. Preoperative, 10-day, 1-month and 3-month postoperative specular microscopy were performed. Mean cell density, coefficient of variation of mean cell area and percentage of hexagonal cells were measured. RESULTS: Mean endothelial cell densities before and 3 months after surgery were 2,240.37 SD 347.92 cells/mm2 (range: 1,020 to 2,703) and 2,283.86 SD 425.13 cells/mm2 (range: 1,001 to 2,837), respectively. Mean coefficient of variation before and 3 months after surgery were 32.63 SD 4.65 (range: 22 to 48) and 33.00 SD 4.75 (range: 23 to 51), respectively. Mean percentage of hexagonal cells before and 3 months after surgery were 54.58 SD 6.60 (range: 46 to 71) and 55.26 SD 8.89 (range: 38 to 76), respectively. No statistically significant differences were found in any of the parameters studied when compared to the preoperative values. CONCLUSIONS: A single intraoperative application of 0.02% MMC for 1 minute during pterygium simple excision surgery does not seem to cause substantial changes in corneal endothelial cell density at 3 months.

[Primary cerebral lymphoma diagnosed by the ophthalmologist]. / Diagnóstico de linfoma cerebral primario por el oftalmólogo.

CASE REPORT: A 20-year-old male, HIV positive, with myodesopsias (floaters) in both eyes for two weeks. Fundus examination revealed bilateral papillary oedema with peripapilar flame-shaped haemorrhages. The neuroimaging tests showed a cerebral mass in the left parietal lobe. The biopsy confirmed the diagnosis of lymphoid neoplasm. DISCUSSION: Primary lymphoma is the most common malignancy of the central nervous system (CNS) in AIDS patients, although highly active antiretroviral therapy has reduced its incidence. The ophthalmologist plays an essential role in the diagnosis of CNS neoplasm.

Análisis morfométrico del endotelio de la córnea tras aplicación intraoperatoria de mitomicina C en la resección simple de pterigión: un estudio piloto / Endothelial cells analysis after intraoperative mitomycin-C adjuvant pterygium simple excision surgery: a pilot study

Objetivo: Evaluar el efecto de la mitomicina C (MMC) sobre el endotelio corneal tras cirugíade pterigión.Método: Estudio clínico intervencional y prospectivo con observador enmascarado. Veintepacientes (20 ojos) con pterigión primario fueron intervenidos mediante resección simpledel pterigión y aplicación intraoperatoria de MMC al 0,02% durante 1 minuto. El endoteliocorneal fue evaluado pre- y postoperatoriamente a los 10 días, al mes y a los 3 meses, conmicroscopía especular. La densidad de las células del endotelio corneal, coeficiente devariación del tamaño celular y porcentaje de hexagonalidad celular fueron analizados.Resultados: Las medias de la densidad de células endoteliales antes y a los 3 meses de lacirugía fueron 2.240,37 desviación estándar (DE) 347,92 células/mm2 (rango: 1.020 a 2.703)y 2.283,86 DE 425,13 células/mm2 (rango: 1.001 a 2.837), respectivamente. Las medias delcoeficiente de variación antes y a los 3 meses de la cirugía fueron 32,63 DE 4,65 (rango: 22a 48) y 33,00 DE 4,75 (rango: 23 a 51), respectivamente. Las medias de los porcentajes dehexagonalidad celular antes y a los 3 meses de la cirugía fueron 54,58 DE 6,60 (rango: 46 a71) y 55,26 DE 8,89 (rango: 38 a 76), respectivamente. No se encontraron diferencias estadísticamentesignificativas en las comparaciones con el valor preoperatorio en ninguna delas variables analizadas.Conclusiones: La aplicación intraoperatoria de MMC al 0,02% durante 1 minuto en la resecciónsimple de pterigión no parece causar cambios sustanciales sobre la densidad de lascélulas del endotelio corneal a corto plazo(AU)

To study the effects of mitomycin-C (MMC) on the corneal endothelium afterpterygium surgery.Methods: Prospective, interventional, nonrandomized, observer-masked study. Twentypatients (20 eyes) with primary pterygium underwent surgery with pterygium simpleexcision followed by 0.02% MMC application for 1 minute. Preoperative, 10-day, 1-monthand 3-month postoperative specular microscopy were performed. Mean cell density,coefficient of variation of mean cell area and percentage of hexagonal cells weremeasured.Results: Mean endothelial cell densities before and 3 months after surgery were 2,240.37 SD347.92 cells/mm2 (range: 1,020 to 2,703) and 2,283.86 SD 425.13 cells/mm2 (range: 1,001 to2,837), respectively. Mean coefficient of variation before and 3 months after surgery were32.63 SD 4.65 (range: 22 to 48) and 33.00 SD 4.75 (range: 23 to 51), respectively. Meanpercentage of hexagonal cells before and 3 months after surgery were 54.58 SD 6.60 (range:46 to 71) and 55.26 SD 8.89 (range: 38 to 76), respectively. No statistically significantdifferences were found in any of the parameters studied when compared to thepreoperative values.Conclusions: A single intraoperative application of 0.02% MMC for 1 minute duringpterygium simple excision surgery does not seem to cause substantial changes in cornealendothelial cell density at 3 months(AU)

Diagnóstico de linfoma cerebral primario por el oftalmólogo / Primary cerebral lymphoma diagnosed by the ophthalmologist

Caso clínico: Paciente varón de 20 años, VIH positivo, con miodesopsias en ambos ojos de 2semanas de evolución. El examen fundoscópico reveló edema de papila bilateral con hemorragiasperipapilares en llama. El estudio de neuroimagen mostró la presencia de unamasa cerebral en el lóbulo parietal izquierdo. La biopsia confirmó el diagnóstico de neoplasiade estirpe linfoide.Discusión: El linfoma primario es la neoplasia más frecuente del sistema nervioso central(SNC) en pacientes con sida (síndrome de inmudeficiencia adquirida) aunque la terapiaantirretroviral de gran actividad ha disminuido su incidencia. Destacamos el papel del oftalmólogoen el diagnóstico de neoplasias del SNC(AU)

Case report: A 20-year-old male, HIV positive, with myodesopsias (floaters) in both eyes fortwo weeks. Fundus examination revealed bilateral papillary oedema with peripapilarflame-shaped haemorrhages. The neuroimaging tests showed a cerebral mass in the leftparietal lobe. The biopsy confirmed the diagnosis of lymphoid neoplasm.Discussion: Primary lymphoma is the most common malignancy of the central nervoussystem (CNS) in AIDS patients, although highly active antiretroviral therapy has reducedits incidence. The ophthalmologist plays an essential role in the diagnosis of CNSneoplasm(AU)

[Expression of embryonic markers in pterygium derived mesenchymal cells]. / Expresión de marcadores embrionarios en células mesenquimales de pterygium.

BACKGROUND: Destruction of the limbal epithelium barrier is the most important mechanism of pterygium formation (conjunctiva proliferation, encroaching onto the cornea). It is thought to arise from activated and proliferating limbal epithelial stem cells. The objective of this study is to evaluate the presence of undifferentiated mesenchymal cells (stem cells) in cultured cells extracted from human pterygium. MATERIAL AND METHODS: Cells from 6 human pterygium were isolated by explantation and placed in cultures with amniomax medium. Once the monolayer was reached the cells were seeded onto 24 well microplates. The cells were studied in the second sub-culture. The immunohistochemical expression of different embryonic stem cell markers, OCT3/4 and CD9, was analysed. The differentiated phenotypes were characterised with the monoclonal antibodies anti-CD31, α-actin and vimentin. RESULTS: All the cell populations obtained from pterygium showed vimentin expression. Less than 1% of the cells were positive for CD31 and α-actin markers. The majority of the cell population was positive for OCT3/4 and CD9. CONCLUSIONS: The cell population obtained from pterygium expressed mesenchymal cell phenotype and embryonic markers, such us OCT3/4 and CD9. This undifferentiated population could be involved in the large recurrence rate of this type of tissue after surgery.

Exoftalmos unilateral como debut de mieloma múltiple no secretor / Unilateral exophthalmos as the debut of a non-secretory multiple myeloma

y diplopía de 2 meses de evolución, exoftalmos unilateralizquierdo con miopatía restrictiva y papiledema.Las pruebas de imagen mostraron lesionesosteolíticas en esfenoides izquierdo, 4.ª costilla ycuerpo de la cuarta vértebra dorsal, con masas departes blandas asociadas. La punción aspiracióncon aguja fina de la lesión confirmó el diagnósticode plasmocitoma. Se diagnosticó de mieloma múltipleno secretor por criterios analíticos y biopsia demédula ósea. Se instauró tratamiento con radioterapialocal y poliquimioterapia.Conclusiones: El oftalmólogo puede desempeñarun papel primordial en el diagnóstico de neoplasiassistémicas, que requieren la intervención de unequipo multidisciplinario(AU)

Case report: A 56 year-old male presented blurredvision and diplopia for 2 months, left unilateralexophthalmos, restricted ocular motility and papilledema.The imaging proofs showed osteolyticlesions in the left sphenoid bone, fourth rib andfourth dorsal vertebral body with associated massesof soft tissues. Biopsy was performed and the diagnosisof plasma cell neoplasm was established. Thediagnosis of non-secretory multiple myeloma wasmade by analytical criteria and bone marrowbiopsy. Local radiotherapy and polychemotherapywas prescribed.Conclusions: The ophthalmologist can play animportant role in the diagnosis of systemic neoplasmsthat require the intervention of a multidisciplinaryteam(AU)

[Corneal melting and topical nonsteroidal anti-inflammatory drug (NSAID). A case report]. / Relación entre anti-inflamatorios no esteroideos (AINES) y queratolisis. A propósito de un caso.

PURPOSE: To study the relationship between the use of nonsteroidal anti-inflammatory drug (NSAID) and the corneal melting. CASE REPORT: We report a case of keratolysis after vitreoretinal surgery and topical use of ketorolac tromethamine (Acular). DISCUSSION: It is proposed the multifactorial etiology in the cases of corneal melting related to the use of NSAID and it is recommended an reasonable use of them in each situation and to check the possible comorbility of other agents.

Relación entre anti-inflamatorios no esteroideos (AINEs) y queratolisis. A propósito de un caso / Corneal melting and topical nonsteroidal anti-inflammatory drug (NSAID). A case report

Objetivo: Establecer la posible relación entre eluso de los antiinflamatorios no esteroideos (AINEs)tópicos y la queratolisis.Caso clínico: Se presenta un caso de queratolisistras cirugía vitreorretiniana y uso tópico de ketorolacotrometamol (Acular®).Discusión: Se plantea la etiología multifactorial enlos casos de queratolisis asociados al uso de AINEsy recomendando un uso de los mismos adecuado acada situación, valorando la posible comorbilidad de otros agentes(AU)

Purpose: To study the relationship between the useof nonsteroidal anti-inflammatory drug (NSAID)and the corneal melting.Case report: We report a case of keratolysis aftervitreoretinal surgery and topical use of ketorolactromethamine (Acular®).Discussion: It is proposed the multifactorial etiologyin the cases of corneal melting related to theuse of NSAID and it is recommended an reasonableuse of them in each situation and to check the possiblecomorbility of other agents(AU)