Papers by Gustavo Bonfadini
Transplantation Proceedings
Investigative Ophthalmology & Visual Science, Mar 26, 2012
Oftalmologia, 2007
RESUMO Objetivo: Determinar as doenças oculares das crianças de três a seis anos de idade de área... more RESUMO Objetivo: Determinar as doenças oculares das crianças de três a seis anos de idade de área assistida pelo Programa de Saúde da Família (PSF) na Lapa-Rio de Janeiro e as causas de ausência à triagem oftalmológica. Métodos: Estudo transversal baseado ...
Encyclopedia of Ophthalmology, 2018
Revista Brasileira De Oftalmologia, 2014
Objective: We describe a novel spatula and dissector to facilitate the big-bubble technique in de... more Objective: We describe a novel spatula and dissector to facilitate the big-bubble technique in deep anterior lamellar keratoplasty (DALK). Methods: A 29-year-old man who was diagnosed with bilateral keratoconus underwent deep anterior lamellar keratoplasty (DALK). After 350µm partial thickness incision of the recipient cornea, the Bonfadini dissector was inserted at the deepest point in the peripheral incision and could be advanced to the center of the cornea safely because of its "semi-sharp" tip. After achieving the big-bubble (BB) separation of Descemet membrane (DM) from the overlying stroma, the anterior stromal disc was removed. Viscoelastic material was placed on the stromal bed to prevent uncontrolled collapse and perforation of DM during the paracentesis blade incision into the BB. We could detect the safe opening of the BB using the Bonfadini dissector by the leakage of air bubbles into the viscoelastic material. After injecting viscoelastic material into the BB space, we inserted the Bonfadini spatula into the bigbubble safely because of its curved profile and blunt edges. The groove along the length of the Bonfadini spatula enables safe and efficient incision or the residual stromal tissue using the pointed end of a sharp blade while protecting the underlying DM. After removal of posterior stroma, the donor button was sutured with 16 interrupted 10-0 nylon sutures. Results: This technique and the use of the Bonfadini spatula and dissector facilitate exposure of Descemet membrane. Conclusion: The smooth Bonfadini DALK spatula and dissector facilitate safe and efficient completion of DALK surgery.
Arquivos brasileiros de oftalmologia, 2015
To investigate the relationship between quantitative iris parameters and the presence of keratoco... more To investigate the relationship between quantitative iris parameters and the presence of keratoconus. Cross-sectional observational study that included 15 affected eyes of 15 patients with keratoconus and 26 eyes of 26 normal age- and sex-matched controls. Iris parameters (area, thickness, and pupil diameter) of affected and unaffected eyes were measured under standardized light and dark conditions using anterior segment optical coherence tomography (AS-OCT). To identify optimal iris thickness cutoff points to maximize the sensitivity and specificity when discriminating keratoconus eyes from normal eyes, the analysis included the use of receiver operating characteristic (ROC) curves. Iris thickness and area were lower in keratoconus eyes than in normal eyes. The mean thickness at the pupillary margin under both light and dark conditions was found to be the best parameter for discriminating normal patients from keratoconus patients. Diagnostic performance was assessed by the area und...
Revista Brasileira de Oftalmologia, 2014
O presente trabalho objetiva descrever o processo de doação, captação, fila de espera e transplan... more O presente trabalho objetiva descrever o processo de doação, captação, fila de espera e transplante de órgãos e tecidos como uma das políticas de saúde no Brasil e no Estado do Rio de Janeiro, com ênfase nos procedimentos relativos aos transplantes de córnea. A baixa notificação de possíveis doadores e a alta taxa de negativa familiar na doação associado ao insuficiente número de córneas disponibilizadas por Banco de Olhos são os principais fatores que limitam o aumento do número dos transplantes de córnea no Brasil. A criação do Banco de Olhos do Rio de Janeiro, associado a politicas que estimulam o aumento da notificação e captação de córneas visa diminuir a fila de espera para transplante de córnea no Estado.
Ophthalmic Surgery, Lasers, and Imaging, 2012
The authors describe "iris-assisted," open-sky, continuous curvilinear capsulorhexis (CCC) in a t... more The authors describe "iris-assisted," open-sky, continuous curvilinear capsulorhexis (CCC) in a triple procedure combining corneal transplantation, cataract extraction, and intraocular lens implantation. They do not use miotics or mydriatics. Patients receive oral acetazolamide (250 mg), intravenous mannitol (5 mL/kg), and Honan balloon at 30 mm Hg for 20 to 30 minutes before surgery. After trephination and excision of recipient cornea, the pupil assumes a mid-dilated position. After injection of 2.3% hyaluronic acid into the anterior chamber, a central linear incision is made in the anterior capsule using a cystotome needle and a CCC is made (approximately 5.5 mm) along the pupillary margin with CCC forceps. The mid-dilated iris can "assist" by resisting posterior pressure to reduce the risk of capsular extension. The nucleus passes through the capsulorhexis following hydrodissection. The keratoplasty is completed followed by cortex removal and in-the-bag intraocular lens implantation, which are facilitated by the CCC in a closed system.
Cornea, 2014
We describe an inexpensive, simple, and effective endothelium-Descemet membrane (EDM) graft injec... more We describe an inexpensive, simple, and effective endothelium-Descemet membrane (EDM) graft injector assembled from regular operating room supplies in Descemet membrane endothelial keratoplasty (DMEK). To assemble the injector, standard intravenous tubing was cut approximately 2 inches from the Luer lock end, leaving a steep bevel. The cut end of the tubing was firmly wedged bevel up and advanced into the back of an Alcon IOL B cartridge. The Luer lock end of the tubing was then attached to a 5- or 10-mL syringe filled with BSS Plus. The EDM graft was then placed into a Petri dish filled with BSS. After the graft was sucked into an injector with bevel-side up under the surgical microscope, the graft was then inserted into the anterior chamber with the injector through the main incision in the superotemporal quadrant. In seven eyes of seven patients with Fuchs endothelial corneal dystrophy treated with DMEK using our injector, clear attached grafts and improved visual acuity were achieved. This simple, inexpensive, and effective injector is a safe and viable device to facilitate this part of DMEK surgery.
Cornea, 2013
A variation of the femtosecond laser-assisted sutureless anterior lamellar keratoplasty technique... more A variation of the femtosecond laser-assisted sutureless anterior lamellar keratoplasty technique using a femtosecond laser incision for surgical management of anterior corneal disease is described. Six patients with corneal scars were treated with the laser to create a horizontal lamellar bed interface in the cornea of the donor and recipient eyes, with a manual partial-thickness vertical trephination to complete the excisions. This technique allows matching of donor and host tissue dimensions with precise tissue apposition and greater surface area for healing. No intraoperative adverse events were observed. One patient developed epithelial ingrowth, requiring a successful surgical intervention.
To evaluate the accuracy of intraocular lens (IOL) power calculations with A-constant optimizatio... more To evaluate the accuracy of intraocular lens (IOL) power calculations with A-constant optimization in Descemet's stripping automated endothelial keratoplasty (DSAEK) combined with cataract extraction and intraocular lens implantation (DSAEK triple procedure). Retrospective case series. Thirty eyes of 22 patients with Fuchs' endothelial dystrophy who underwent the DSAEK triple procedure performed by a single surgeon. Prediction errors were calculated retrospectively for consecutive DSAEK triple procedures. These prediction errors then were used to determine an IOL constant for this cohort of patients. The new optimized IOL constant subsequently was compared with the manufacturer's IOL constant, allowing evaluation and quantification of refractive benefits of optimization. The error in diopters (D) of the predicted refraction with the manufacturer's and optimized IOL constants. Optimization of the A constant decreased the mean absolute error (MAE) from 1.09 ± 0.63 D (range, 0.12-2.41 D) to 0.61 ± 0.4 D (range, 0-1.58 D; P = 0.004). Comparing the intended and final postoperative refractions calculated with the original manufacturer's constant and the optimized constant, 20% versus 43% of all eyes were in the less than 0.5-D range and 50% versus 83% of all eyes were in the less than 1.0-D range of the target refraction. Furthermore, optimization decreased the number of eyes that were more than 1.0 D from the target refraction from 50% to 17%. Optimization of the IOL constant showed significantly improved accuracy of predicted postoperative refraction compared with the manufacturer's IOL constant, which may help improve the postoperative refractive outcomes in patients undergoing the DSAEK triple procedure.
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Papers by Gustavo Bonfadini