Francia Torres | (Benemérita) Universidad Autónoma de Puebla (original) (raw)

Papers by Francia Torres

La serie de Documentos de Investigación del Banco de México divulga resultados preliminares de tr... more La serie de Documentos de Investigación del Banco de México divulga resultados preliminares de trabajos de investigación económica realizados en el Banco de México con la finalidad de propiciar el intercambio y debate de ideas. El contenido de los Documentos de Investigación, así como las conclusiones que de ellos se derivan, son responsabilidad exclusiva de los autores y no reflejan necesariamente las del Banco de México.

Retina-the Journal of Retinal and Vitreous Diseases, 2000

To report a case series of rhegmatogenous retinal detachment (RRD) after laser-assisted in situ k... more To report a case series of rhegmatogenous retinal detachment (RRD) after laser-assisted in situ keratomileusis (LASIK) and its incidence at a mean of 24 months. The clinical charts of patients who experienced RRD after LASIK were reviewed. Five refractive surgeons and 24,890 myopic eyes that underwent surgical correction of myopia ranging from -0.75 to -29.00 diopters (D) (mean, -6.19 D) participated in this study. Thirteen eyes from 12 patients developed RRD after LASIK. Rhegmatogenous RD occurred between 1 and 36 months (mean, 12.6 months) after LASIK. Eyes that developed RRD had from -1.50 to -16.00 D of myopia (mean, -6.96 D) before LASIK. Rhegmatogenous RD were managed with vitrectomy, cryoretinopexy, scleral buckling, argon laser retinopexy, or pneumatic retinopexy techniques. The incidence of RRD at a mean of 24 months after LASIK in this study was 0.05%. Rhegmatogenous RD after LASIK is infrequent. If managed promptly, good vision can result. No cause-effect relationship between LASIK and RD can be proved from this study, but the authors recommend that patients scheduled for refractive surgery undergo a thorough dilated indirect fundus examination with scleral depression and treatment of any retinal lesions predisposing them to the development of RRD before LASIK surgery is performed.

International Ophthalmology Clinics, 1996

Wolters Kluwer Health may email you for journal alerts and information, but is committed to maint... more Wolters Kluwer Health may email you for journal alerts and information, but is committed to maintaining your privacy and will not share your personal information without your express consent. For more information, please refer to our Privacy Policy. ... Skip Navigation Links Home > Fall ...

Ophthalmology, 2001

To assess the posterior corneal power and asphericity changes after myopic laser in situ keratomi... more To assess the posterior corneal power and asphericity changes after myopic laser in situ keratomileusis (LASIK) and to correlate these changes with the amount of correction and the residual stromal bed thickness. Prospective nonrandomized (self-controlled) comparative study. Fifty-seven eyes of 14 women and 15 men, mean age at the time of surgery 33 +/- 9 (range, 19-53) years with a spherical equivalent (SEQ) of -1.00 to -15.50 (mean, -5.07 +/- 2.81) diopters (DI). All procedures were performed with the Keratom II Coherent-Schwind excimer laser and and the Moria Model One microkeratome (150-microm head). Subjective refractometry, Orbscan slit scanning corneal topography analysis and pachymetry were performed before and 3 months after LASIK for myopia (n=35, -1.00 to -15.50 D, mean -4.75 +/- -3.07 D) or myopic astigmatism (n=22, sphere 0.00 to -9.75 D, mean -4.75 +/- 2.36 D; cylinder -0.75 to -3.50 D, mean -1.68 +/- 0.86 D). Intended ablation depth ranged from 12 to 108 (mean, 48 +/- 22) microm. Topographic raw data were decomposed into a set of Zernike polynomials as published in detail previously, and parameters potentially indicative for detection of a "mild keratectasia" were derived. Posterior central corneal power and asphericity before and after LASIK were compared, and changes of these variables were correlated with the SEQ change (deltaSEQ)and the residual corneal bed thickness RBT). The mean RBT after LASIK was 280 +/- 42 microm. Overall, change of posterior power (-6.28 +/- 0.22 D/ -6.39 +/- 0.23 D, P=0.02) was statistically significant and change of asphericity (0.98 +/-0.07/1.14 +/- -.20, P<0.0001) was highly significant. In eyes with RBT < or =250 microm, the average change of posterior central power (-0.20 +/- 0.10 D vs. -0.08 +/- 0.18 D) was significantly greater than in eyes with RBT >250 microm (P=0.003). The change of posterior corneal power correlated significantly with deltaSEQ (P=0.004) and the RBT (P=0.002). Increased negative keratometric diopters and oblate asphericity of the posterior corneal curvature suggest that mild "keratectesia" of the cornea may be common early after LASIK. Further stuudies with longer follow-up are required to clarify whether this biomechanical deformation is progressive and whether a residual bed thickness of >250 microm can completely prevent it.

Journal of Cataract and Refractive Surgery, 2001

To report the characteristics and frequency of rhegmatogenous retinal detachment (RRD) after lase... more To report the characteristics and frequency of rhegmatogenous retinal detachment (RRD) after laser in situ keratomileusis (LASIK) for the correction of myopia in a large case series. Private practices, Caracas, Venezuela. Five refractive surgeons and 31 739 myopic eyes that had surgical correction of a mean myopia of -6.01 diopters (D) (range -0.75 to -29.00 D) participated in this study. Laser in situ keratomileusis was performed in all eyes. Patients were followed for a mean of 36 months (range 6 to 48 months). The clinical charts of patients who developed RRD after LASIK were reviewed. Twenty eyes (17 patients) developed RRD after LASIK. Rhegmatogenous retinal detachments occurred a mean of 13.9 months (range 1 to 36 months) after LASIK. The mean pre-LASIK myopia in eyes that developed an RRD was -7.02 D (range -1.50 to -16.00 D). Most RRDs and retinal breaks occurred in the temporal quadrants (71.4%). Rhegmatogenous retinal detachments were managed with vitrectomy, cryoretinopexy, scleral buckling, argon laser retinopexy, or pneumatic retinopexy techniques. The frequency of RRD after LASIK was 0.06%. Rhegmatogenous retinal detachment after LASIK for the correction of myopia is infrequent. If managed promptly, RRD will result in good vision. Before LASIK is performed, patients should have a thorough dilated indirect fundoscopy with scleral depression and treatment of any retinal lesion predisposing to the development of an RRD.

Journal of Cataract and Refractive Surgery, 2002

Purpose: To report a case series of anterior uveitis after laser in situ keratomileusis (LASIK) a... more Purpose: To report a case series of anterior uveitis after laser in situ keratomileusis (LASIK) and the incidence of anterior uveitis at a mean of 3 years.

American Journal of Ophthalmology, 2003

therefore, routinely select other viewing methods. To determine whether our impressions were cons... more therefore, routinely select other viewing methods. To determine whether our impressions were consistent with the experience of other surgeons, we conducted a brief survey.

Acta Ophthalmologica Scandinavica, 2004

Purpose: To evaluate the effect of a separate measurement of the anterior and posterior corneal s... more Purpose: To evaluate the effect of a separate measurement of the anterior and posterior corneal surface to calculate the total refractive power of the cornea after myopic laser in situ keratomileusis (LASIK). Methods: A total of 39 eyes of 21 patients (aged 33 AE 9 years) were included in this prospective, non-randomized, comparative study. These involved 19 myopic corrections (À 3.5 AE 1.6 dioptres) and 23 refractive corrections of myopic astigmatism (sphere: À3.7 AE 1.6 D, cylinder: À1.2 AE 0.4 D). All procedures were accomplished with the Keratom II 1 . Coherent-Schwind excimer laser and the Moria Model One 1 microkeratome (150 mm head) at the Medical Education Centre, La Trinidad, Caracas, Venezuela. Subjective refractometry, Bausch & Lomb 1 keratometry and Orbscan 1 slit-scanning corneal topography analysis were performed before and 3 months after LASIK. Corneal power was assessed directly using keratometry (K1) and Orbscan videokeratography (T1). Corneal power was calculated using the preoperative keratometric (K2, 'gold standard', clinical history method) or topographic power (T2, clinical history method) and spherical equivalent change. A composite value was derived from the Orbscan anterior and posterior surface power and central pachymetry (T3). Results: Three months postoperatively, corneal power ranged in a descending order from T1 (42.33 AE 1.78 D), K1 (40.82 AE 2.20 D), K2 (40.42 AE 2.36 D), T2 (40.03 AE 2.51 D) to T3 (38.78 AE 2.23 D). On average, T1 exceeded the gold standard by 1.9 D and the gold standard exceeded T3 by 1.6 D. K2, T1, T2 and T3 correlated significantly with K1 (r ¼ 0.975, p < 0.001; r ¼ 0.909, p < 0.001; r ¼ 0.963, p < 0.001; r ¼ 0.853, p < 0.001, respectively). The differences T1ÀK2 (r ¼ À 0.699, p < 0.001) and T3ÀK2 (r ¼ À 0.499, p ¼ 0.001) correlated highly inversely and K1ÀK2 correlated borderline inversely (r ¼ À 0.325, p ¼ 0.043) with the intended refractive correction. Conclusion: After myopic LASIK, refractive corneal power is overestimated by direct keratometric and especially videokeratoscopic measurements. The higher the intended refractive correction, the greater is this error. A separate measurement of both refractive surfaces of the cornea tends to underestimate but may enhance accuracy of the total refractive corneal power if the history of the patient is unknown.