NATALIA TORRES GIACOMIN
Projetos de Pesquisa
Unidades Organizacionais
LIM/33 - Laboratório de Oftalmologia, Hospital das Clínicas, Faculdade de Medicina
8 resultados
Resultados de Busca
Agora exibindo 1 - 8 de 8
- Advances in femtosecond laser technology(2016) CALLOU, Thais Pinheiro; GARCIA, Renato; MUKAI, Adriana; GIACOMIN, Natalia T.; SOUZA, Rodrigo Guimaraes de; BECHARA, Samir J.Femtosecond laser technology has become widely adopted by ophthalmic surgeons. The purpose of this study is to discuss applications and advantages of femtosecond lasers over traditional manual techniques, and related unique complications in cataract surgery and corneal refractive surgical procedures, including: LASIK flap creation, intracorneal ring segment implantation, presbyopic treatments, keratoplasty, astigmatic keratotomy, and intrastromal lenticule procedures.
- Intracorneal Ring Segments Implantation for Corneal Ectasia(2016) GIACOMIN, Natalia T.; MELLO, Glauco R.; MEDEIROS, Carla S.; KILIC, Alyin; SERPE, Cristine C.; ALMEIDA, Hirlana G.; KARA-JUNIOR, Newton; SANTHIAGO, Marcony R.PURPOSE: To provide an overview of the predictability, safety, and efficacy of intrastromal corneal ring segment (ICRS) implantation as a tool to improve visual acuity and its association with other techniques such as corneal collagen cross-linking (CXL), addressing biomechanical outcomes, models, surgical planning and technique, indications, contraindications, and complications in ectatic corneas. METHODS: Literature review. RESULTS: ICRSs have been used to regularize the corneal shape and reduce corneal astigmatism and higher order aberrations, improve visual acuity to acceptable limits, and delay, or eventually prevent, a corneal keratoplasty in keratoconic eyes. Changes in ICRS thickness and size, combination of techniques, and the addition of femtosecond lasers to dissect more foreseeable channels represent an improvement toward more predictable results. Several studies have shown, over time, the long-term efficacy and safety of ICRS treatment for keratoconus, with variable predictability, maintaining the early satisfactory outcomes regarding visual acuity, keratometry, and corneal thickness. It is just as important to ensure that the disease will not progress as it is to improve the visual acuity. Therefore, many studies have shown combined techniques using ICRS implantation and CXL. Also, further limitations of ICRS implantation can be addressed when associated with phakic intraocular lens implantation and photorefractive keratectomy. CONCLUSIONS: ICRS implantation has shown effectiveness and safety in most cases, including combined procedures. In properly selected eyes, it can improve both refraction and vision in patients with keratoconus.
- The Role of Thyroid Gland Dysfunction in the Development of Keratoconus(2022) STIVAL, L. R. S.; GIACOMIN, N. T.; SANTHIAGO, M. R.The number of studies on the development of thyroid gland dysfunction and keratoconus highlights the multifactorial nature of the disease. Many factors seem to be related to keratoconus, such as genetic predisposition, inflammatory markers, environmental conditions, eye rubbing, and metabolic and structural changes, in addition to systemic diseases and hormonal changes. There seems to be evidence that hormonal changes caused by thyroid gland dysfunction are additional factors that, through influencing the corneal structure, could affect keratoconus progression. Thyroid hormones are regulated by the pituitary axis of the thyroid (HPT) and can be imbalanced, besides primary genetic defects, by activating factors that alter homeostasis such as pregnancy, thyroidectomy, or iodine therapy. In this chapter, we emphasize the scientific evidence related to thyroid hormones and the possible correlation to keratoconus. © The Editor(s) (if applicable) and The Author(s), under exclusive license to Springer Nature Switzerland AG 2022.
- Corneal Collagen Cross-linking in Advanced Keratoconus: A 4-Year Follow-up Study(2016) GIACOMIN, Natalia T.; NETTO, Marcelo V.; TORRICELLI, Andre A. M.; MARINO, Gustavo K.; BECHARA, Samir J.; ESPINDOLA, Rodrigo F.; SANTHIAGO, Marcony R.PURPOSE: To analyze the safety and efficacy of standard corneal collagen cross-linking (CXL) in advanced cases of progressive keratoconus after 4 years of follow-up. METHODS: A retrospective case series of patients with advanced progressive keratoconus (stages 3 and 4 of Amsler-Krumeich classification) underwent standard CXL treatment. The parameters examined were changes in uncorrected visual acuity (UDVA), corrected visual acuity (CDVA), keratometry values (mean, flat, steep, and apical), pachymetry, and endothelial cell count at the baseline and at 12, 24, and 48 months postoperatively. RESULTS: Forty eyes of 40 patients were enrolled in the study. The mean patient age was 22.5 years (range: 15 to 37 years). Both mean UDVA and CDVA remained stable during the time points; no statistically significant change was noted. Although a slight reduction was observed in all keratometric readings, a statistically significant reduction was only reached in the apical keratometry (P = .037) at 4 years after CXL. A significant reduction in the corneal thickness was also found (ultrasonic: 388 +/- 49 to 379 +/- 48 mu m; slit-scanning: 362 +/- 48 to 353 +/- 51 mu m); however, this change was likely not clinically meaningful. Endothelial cell count was not significantly different at the end of the study. Treatment failure or progression was noted in two patients (5%) over the follow-up period. CONCLUSIONS: Standard CXL treatment was safe and able to stabilize both visual acuity and topographic parameters at 4 years of follow-up in eyes with advanced keratoconus.
- Intense Early Flattening After Corneal Collagen Cross-linking(2015) SANTHIAGO, Marcony R.; GIACOMIN, Natalia T.; MEDEIROS, Carla S.; SMADJA, David; BECHARA, Samir J.PURPOSE: To report two cases of significant flattening after corneal cross-linking (CXL) for keratoconus and discuss its potential explanations and implications. METHODS: Observational case report. RESULTS: One year after standard CXL protocol (3 mW/cm(2) for 30 minutes and total energy of 5.4 J/cm(2)), a 28-year-old woman presented a flattening of greater than 14 diopters and a 14-year-old boy presented a flattening of 7 diopters. CONCLUSIONS: Although rare, a significant flattening effect may occur during the first year after CXL, probably related to intense wound healing, increase in corneal elasticity, CXL effective depth, and central cone location. These cases suggest the necessity of a patient-specific approach and a better understanding regarding the actual mechanism behind its potent effect.
- Intrastromal Corneal Rings and Photorefractive Keratectomy(2022) GIACOMIN, N. T.; STIVAL, L. R. S.The visual rehabilitation for keratoconic corneas requires addressing three concerns: halting the ectatic process, improving corneal shape, and minimizing the residual refractive error. ICRS implantation can improve the corneal shape and hence the visual quality and reduce the refractive error; PRK can treat part of the refractive error. The prior use of ICRS induces corneal flattening and reduces keratometric astigmatism allowing a controlled PRK treatment with minimal tissue ablation. Although a combination of PRK + ICRS when associated to CXL demonstrated to be an effective and safe option for correcting mild refractive errors and improving visual acuity, studies with larger cohorts and longer follow-up periods are needed to determine which refractive procedure and/or sequence are most suitable for each case. © The Editor(s) (if applicable) and The Author(s), under exclusive license to Springer Nature Switzerland AG 2022.
- Accelerated corneal collagen crosslinking: Technique, efficacy, safety, and applications(2016) MEDEIROS, Carla S.; GIACOMIN, Natalia T.; BUENO, Renata L.; GHANEM, Ramon C.; MORAES JR., Haroldo V.; SANTHIAGO, Marcony R.Corneal collagen crosslinking (CXL) is an approach used to increase the biomechanical stability of the stromal tissue. Over the past 10 years, it has been used to halt the progression of ectatic diseases. According to the photochemical law of reciprocity, the same photochemical effect is achieved with reduced illumination time and correspondingly increased irradiation intensity. Several new CXL devices offer high ultraviolet-A irradiation intensity with different time settings. The main purpose of this review was to discuss the current use of different protocols of accelerated CXL and compare the efficacy and safety of accelerated CXL with the efficacy and safety of the established conventional method. Accelerated CXL proved to be safe and effective in halting progression of corneal ectasia. Corneal shape responses varied considerably, as did the demarcation line at different irradiance settings; the shorter the exposure time, the more superficial the demarcation line. (C) 2016 ASCRS and ESCRS
- Accelerated Corneal Collagen Cross-linking for Postoperative LASIK Ectasia: Two-Year Outcomes(2015) MARINO, Gustavo K.; TORRICELLI, Andre A. M.; GIACOMIN, Natalia; SANTHIAGO, Marcony R.; ESPINDOLA, Rodrigo; NETTO, Marcelo V.PURPOSE: To evaluate the effectiveness and safety of accelerated corneal collagen cross-linking for postoperative LASIK ectasia after 2 years. METHODS: A prospective, single-center case series was performed with patients treated for postoperative LASIK ectasia. All eyes underwent accelerated corneal collagen cross-linking (CCL-Vario Crosslinking; Peschke Meditrade GmbH, Zurich, Switzerland) at 9 mW/cm(2) for 10 minutes. The main outcome measures were changes in uncorrected distance visual acuity, corrected distance visual acuity, central corneal thickness, corneal topography, and endothelial cell density. These parameters were assessed at baseline and at the 6-month and 1- and 2-year follow-up visit. RESULTS: The study enrolled 40 eyes of 24 patients (15 male and 9 female) with a mean age of 33.8 +/- 7.5 years (range: 24 to 52 years) that attained at least 2 years of follow-up. The surgical procedure was uneventful in all cases. All eyes stabilized after treatment without any further signs of progression and no statistically significant changes in the mean uncorrected distance visual acuity (P = .649), corrected distance visual acuity (P = .616), mean keratometry (P =. 837), steep keratometry (P = .956), ultrasonic pachymetry (P = .135), slit-scanning pachymetry (P = .276), and endothelial cell density (P = .523). In addition, 72.5% of the patients presented stable or gains of Snellen lines over time. CONCLUSIONS: Accelerated corneal collagen cross-linking seems to be safe and effective in halting postoperative LASIK ectasia progression after 2 years of follow-up. However, a longer follow-up period with a larger cohort is needed to validate these findings.