Optimization of intraocular lens constant improves refractive outcomes in combined endothelial keratoplasty and cataract surgery.

PURPOSE: 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). DESIGN: Retrospective case series. PARTICIPANTS: Thirty eyes of 22 patients with Fuchs' endothelial dystrophy who underwent the DSAEK triple procedure performed by a single surgeon. METHODS: 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. MAIN OUTCOMES MEASURES: The error in diopters (D) of the predicted refraction with the manufacturer's and optimized IOL constants. RESULTS: 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%. CONCLUSIONS: 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.

Comprehensive Retrospective Analysis of Corneal Donor Characteristics at the National Institute of Traumatology and Orthopedics Eye Bank (2013-2021).

BACKGROUND: Corneal transplantation success depends on good practices in tissue selection and preservation. This study aimed to assess the relationship between the time from the donor's death to the end of processing and corneal cellularity provided by the Eye Bank. METHODS: This was a retrospective study of 839 donor records (2013-2021) from the Eye Bank of the National Institute of Traumatology and Orthopedics, totaling 1445 corneas. Donors were classified based on cellularity (≤2000 and >2000 cells/mm2) and laterality. The dependent variable was cellularity in the right eye (RE) and left eye (LE), categorized into ≤2000 and >2000 cells/mm2 groups. Independent variables included sex, age, cause of death, and Δ-death. The statistical software SPSS 26.0 (IBM SPSS, Inc, Armonk, NY, United States) was used, and P < 0.05 was considered significant. RESULTS: Among 839 donors, most were male (58.2%) and ≥60 years old (36.5%). Brain death (BD) was the primary cause of death (66.2%). A time from the donor's death to the end of processing interval of ≥10 hours occurred in 35.6% of cases. Cellularity >2000 cells/mm2 was similar for the RE (94.5%) and LE (93.9%). Age showed statistical significance (P < 0.001) in both eyes, with cellularity decreasing for donors ≥60 years. In BD cases, higher cellularity was observed in the LE (P < 0.001; 70.8%). A time from the donor's death to the end of processing interval and cellularity comparison showed relevance for the LE (P = 0.03) but no association for the RE. CONCLUSIONS: Corneal cellularity decreased with increasing donor age. Significant differences in Δ-death were associated with cellularity, BD, and right and left cornea.

Quantitative analysis of iris parameters in keratoconus patients using optical coherence tomography.

PURPOSE: To investigate the relationship between quantitative iris parameters and the presence of keratoconus. METHODS: 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. RESULTS: 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 under the ROC curve (AROC), which had a value of 0.8256 with 80.0% sensitivity and 84.6% specificity, using a cutoff of 0.4125 mm. The sensitivity increased to 86.7% when a cutoff of 0.4700 mm was used. CONCLUSIONS: In our sample, iris thickness was lower in keratoconus eyes than in normal eyes. These results suggest that tomographic parameters may provide novel adjunct approaches for keratoconus screening.

Simple, inexpensive, and effective injector for descemet membrane endothelial keratoplasty.

PURPOSE: 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). METHODS: 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. RESULTS: 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. CONCLUSIONS: This simple, inexpensive, and effective injector is a safe and viable device to facilitate this part of DMEK surgery.

Modified femtosecond laser-assisted sutureless anterior lamellar keratoplasty.

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.

"Iris-assisted," open-sky, continuous curvilinear capsulorhexis technique for combined cataract extraction and corneal transplantation.

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.

Quantitative analysis of iris parameters in keratoconus patients using optical coherence tomography / Uso de tomografia de coerência óptica na análise quantitativa dos parâmetros irianos em pacientes com ceratocone

ABSTRACTPurpose:To investigate the relationship between quantitative iris parameters and the presence of keratoconus.Methods: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.Results: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 under the ROC curve (AROC), which had a value of 0.8256 with 80.0% sensitivity and 84.6% specificity, using a cutoff of 0.4125 mm. The sensitivity increased to 86.7% when a cutoff of 0.4700 mm was used.Conclusions:In our sample, iris thickness was lower in keratoconus eyes than in normal eyes. These results suggest that tomographic parameters may provide novel adjunct approaches for keratoconus screening.

RESUMOObjetivo:Investigar a relação entre os parâmetros quantitativos irianos e a presença de ceratocone.Métodos:Estudo observacional transversal com quinze olhos de 15 pacientes com ceratocone e 26 olhos de 26 indivíduos normais, pareados por idade e gênero. Parâmetros da íris (área, espessura e diâmetro da pupila) de olhos com ceratocone e olhos sem ceratocone foram medidos usando tomografia de coerência óptica do segmento anterior (AS-OCT), em condições padronizadas de alta luminosidade e ambiente escuro. Com o objetivo de maximizar a sensibilidade, especificidade e identificar o melhor ponto de corte na diferenciação entre ceratocone e indivíduos normais, foi realizada a análise quantitativa da curva característica operacional do receptor (ROC) dos parâmetros de espessura da íris.Resultados:A área e espessura da íris estavam reduzidas nos olhos de pacientes com ceratocone. Observamos que o melhor parâmetro para discriminar indivíduos normais de pacientes com ceratocone foi a espessura média na margem pupilar, tanto em condições de alta luminosidade quanto em ambiente escuro. O desempenho diagnóstico deste parâmetro foi avaliado pela análise quantitativa da área sob a curva ROC (AROC), mostrando AROC de 0,8256, com sensibilidade de 80,0% e especificidade de 84,6% usando um ponto de corte de 0,4125 milímetros de espessura da íris. A sensibilidade aumentou para 86,7%, com um corte de 0,4700 milímetros de espessura da íris.Conclusões:Na amostra deste estudo, a espessura da íris demostrou-se reduzida nos olhos com ceratocone. Estes resultados sugerem que os parâmetros tomográficos podem proporcionar novas informações no auxilio da triagem de pacientes com ceratocone.

Doação e fila de transplante de córnea no Estado do Rio de Janeiro / Donation and waiting list for corneal transplantation in the State of Rio de Janeiro

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.

This paper aims to describe the process of organ and tissue donation, tissue harvesting, queue and transplants as a health policy in Brazil and in the State of Rio de Janeiro, with emphasis on procedures for corneal transplantation. The low reporting of possible donors associated with a high rate of negative family in donation, associated with the insufficient number of corneas provided by Eye Banks are the main factors limiting the increase in the number of corneal transplants in Brazil. The creation of the Rio de Janeiro Eye Bank associated with policies that encourage increased reporting and collection of corneas aims to reduce the waiting list for corneal transplantation in Rio de Janeiro State.

Novel spatula and dissector for safer deep anterior lamellar keratoplasty / Uso de espátula e dissector para otimização da ceratoplastia lamelar anterior profunda (DALK)

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. .

Objetivo: Descrevemos o uso de novos instrumentais cirúrgicos para facilitar a técnica de "big-bubble" na ceratoplastia lamelar anterior profunda (DALK). Métodos: Paciente masculino, 29 anos, foi diagnosticado com ceratocone bilateral e submetido à ceratoplastia lamelar anterior profunda (DALK). Após incisão da córnea receptora numa profundidade de 350μm de espessura parcial, o dissector Bonfadini foi inserido no ponto mais profundo da incisão periférica e pode avançar para o centro da córnea com segurança devido à sua ponta semiafiada. Depois de realizar a "big-bubble" (BB) e atingir a separação da Membrana de Descemet (MD) do estroma sobrejacente, o disco corneano de estroma anterior foi removido. Um viscoelástico foi colocado sobre o leito do estroma remanescente para impedir o colapso não-controlado e perfuração da MD durante a incisão na BB com lâmina de paracentese. Verificamos segurança no rompimento do estroma remanescente com o auxílio do dissector Bonfadini, para liberação da bolha de ar da BB através do viscoelástico. Depois de injetar o viscoelástico no espaço da BB, inserimos a espátula Bonfadini neste espaço, o que demonstrou-se seguro devido ao formato curvo e das bordas arredondadas do instrumental. A chanfradura ao longo do comprimento da espátula Bonfadini permite a incisão pela ponta de uma lâmina afiada, protegendo assim a MD subjacente. Após a remoção do estroma posterior, o botão doador foi suturado com 16 pontos interrompidos de fio nylon 10.0. Resultados: Esta técnica e o uso da espátula Bonfadini e dissector facilitam a exposição de membrana de Descemet. Conclusão: A superfície lisa da espátula Bonfadini e dissector, facilitam a realização segura e eficiente da ceratoplastia lamelar anterior profunda (DALK). .