Efecto de los segmentos anulares intracorneales en la topografía corneal posterior en ojos con queratocono / Effect of intracorneal ring segments on posterior corneal topography in eyes with keratoconus

Objetivo Analizar los cambios en las superficies corneales anterior y posterior medidos con un dispositivo de imágenes Scheimpflug en pacientes con queratocono implantados con segmentos anulares intracorneales y correlacionar esos cambios con los resultados visuales. Métodos Este estudio prospectivo de serie de casos de intervención incluyó 92 ojos de 60 pacientes con queratocono a los que se implantó segmentos anulares intracorneales de Kerarings (Mediphacos, Belo Horizonte, Brasil). Se evaluaron las lecturas queratométricas (K), la asfericidad corneal (valor Q) y las elevaciones de las superficies corneales anterior y posterior mediante un dispositivo de imágenes Scheimpflug antes de la operación y a los uno, 3, 6 y 12 meses después de la misma. Resultados La mejor agudeza visual corregida (MAVC) mejoró de 0,61 a 0,19 logMAR a los 12 meses de la cirugía. Tanto la superficie corneal anterior como la posterior mostraron un aplanamiento significativo con una reducción estadísticamente significativa de la lectura K anterior media en 3,39 D y de la lectura K posterior media en 0,39 D (p<0,001) a los 12 meses. Se observó un cambio estadísticamente significativo del Q anterior a un valor menos negativo (de −1,05 a −0,36) (p<0,001) sin que se produjera ningún cambio significativo en el valor del Q posterior. La mejora del Q anterior se correlacionó significativamente con una mejor MAVC postoperatoria (p=0,03). Una mejor MAVC postoperatoria se correlacionó significativamente con una mejor MAVC preoperatoria, una K anterior y posterior más plana, un valor Q anterior menos prolato y menores elevaciones anteriores. Conclusiones La implantación de segmentos anulares intracorneales tiene un efecto de aplanamiento significativo en las superficies corneales anteriores y posteriores. La mejora de la asfericidad corneal se correlaciona con un mejor resultado visual. Algunos parámetros preoperatorios fueron factores predictivos de la mejora visual postoperatoria (AU)

Purpose To analyze the changes in the anterior and posterior corneal surfaces measured with a Scheimpflug imaging device in keratoconus patients implanted with intracorneal ring segments and to correlate those changes with the visual outcomes. Methods This prospective interventional case series study included 92 eyes of 60 patients with keratoconus who underwent Kerarings (Mediphacos, Belo Horizonte, Brazil) intracorneal ring segments implantation. Keratometric (K) readings, corneal asphericity (Q value) and elevations of both anterior and posterior corneal surfaces were evaluated using a Scheimpflug imaging device preoperatively and at one, 3, 6 and 12 months after surgery. Result The mean best corrected visual acuity (BCVA) improved from 0.61 to 0.19 logMAR at 12 months after surgery. Both anterior and posterior corneal surfaces showed significant flattening with statistically significant reduction of the mean anterior K reading by 3.39 D and the mean posterior K reading by 0.39 D (P<.001) at 12 months. Statistically significant change of the anterior Q to a less negative value (from −1.05 to −0.36) was observed (P<.001) with no significant change of the posterior Q value. Improvement of the anterior Q was significantly correlated to better postoperative BCVA (P=.03). Better postoperative BCVA significantly correlated to better preoperative BCVA, flatter preoperative anterior and posterior K, less prolate anterior Q value and lower anterior elevations. Conclusions Implanted with intracorneal ring segments implantation has a significant flattening effect on both anterior and posterior corneal surfaces. Improvement of corneal asphericity is correlated to better visual outcome. Certain preoperative parameters were predictive factors of the postoperative visual improvement (AU)

Effect of intracorneal ring segments on posterior corneal topography in eyes with keratoconus.

PURPOSE: To analyze the changes in the anterior and posterior corneal surfaces measured with a Scheimpflug imaging device in keratoconus patients implanted with intracorneal ring segments (ICRS) and to correlate those changes with the visual outcomes. METHODS: This prospective interventional case series study included 92 eyes of 60 patients with keratoconus who underwent Kerarings (Mediphacos, Belo Horizonte, Brazil) ICRS implantation. Keratometric (K) readings, corneal asphericity (Q value) and elevations of both anterior and posterior corneal surfaces were evaluated using a Scheimpflug imaging device preoperatively and at 1, 3, 6 and 12 months after surgery. RESULTS: The mean best corrected visual acuity (BCVA) improved from 0.61 to 0.19 logMAR at 12 months after surgery. Both anterior and posterior corneal surfaces showed significant flattening with statistically significant reduction of the mean anterior K reading by 3.39 D and the mean posterior K reading by 0.39 D (p<0.001) at 12 months. Statistically significant change of the anterior Q to a less negative value (from -1.05 to -0.36) was observed (p<0.001) with no significant change of the posterior Q value. Improvement of the anterior Q was significantly correlated to better postoperative BCVA (p=0.03). Better postoperative BCVA significantly correlated to better preoperative BCVA, flatter preoperative anterior and posterior K, less prolate anterior Q value and lower anterior elevations. CONCLUSIONS: ICRS implantation has a significant flattening effect on both anterior and posterior corneal surfaces. Improvement of corneal asphericity is correlated to better visual outcome. Certain preoperative parameters were predictive factors of the postoperative visual improvement.

Preliminary evaluation of nonpenetrating deep sclerectomy with autologous scleral implant in open-angle glaucoma.

AIM: The aim of this study is to evaluate the short-term result of the use of an autologous scleral implant during the nonpenetrating deep sclerectomy operation instead of the more expensive collagen implant. DESIGN: Prospective nonrandomized pilot study. PATIENTS AND METHODS: This study included 20 eyes of 20 patients with a mean age of 42.3+/-8.1 years and the mean of preoperative best-corrected visual acuity was 0.66+/-6.2. All patients were indicated for conventional deep sclerectomy operation but with implantation of an autologous scleral implant. The operation was considered completely successful if the intraocular pressure (IOP) is below 18 mmHg without medications while qualified success was considered if the IOP was below 18 mmHg with medications. RESULTS: This technique succeeded in declining the mean IOP from 33.1+/-6.2 mmHg preoperatively to 14.6+/-3.8 mmHg postoperatively by the end of the follow-up period (12 months). Complete and qualified successful results were seen in 85% of cases. Nd:YAG goniopuncture was needed in 45% of the cases. This intervention was needed 14.0+/-10.0 weeks postoperatively. The study group showed low incidence of postoperative complication with statistically nonsignificant effect on the postoperative visual acuity. CONCLUSION: The use of autologous scleral implant can be of value in controlling the IOP with low cost to the patient. Nd:YAG goniopuncture is to be performed around the third month postoperatively in cases with advanced glaucomatous changes to avoid the problem of early implant induced fibrosis. Further long-term comparative study on wider scale is needed to detect the exact value of this technique and to evaluate its long-term result.

Antifungal effects of different plant extracts and their major components of selected aloe species.

Different extracts of both fresh and dry leaves of Aloe eru A. Berger, A. vera L. Webb & Berth and A. arborescens Mill. were screened for their antifungal activity against Aspergillus niger, Cladosporium herbarum and Fusarium moniliforme. The toxicity of the isolated pure components were evaluated on the tested fungi. A comparative chromatographic study was performed to differentiate between natural components existing in various fractions and extracts of Aloe species and specific spray reagents were used for the detection of anthraquinones in the isolated components.