Renato Augusto Neves

Intrastromal corneal ring : 12-month sighted myopic eyes

BACKGROUND To evaluate the efficacy, predictability, and stability of the refractive effect produced by the Intrastromal Corneal Ring (ICR), the authors completed a 12-month study on 10 myopic eyes. METHODS Ten patients with preoperative refractive errors ranging from -2.63 diopters (D) to -4.25 D (mean, -3.30 D) participated in the study. The attempted correction was -2.50 D for a 7.0-mm diameter, 0.3-mm thick ICR. One eye of each patient received an ICR. RESULTS The average change in spherical equivalent at 12 months was -2.25 D (SD 0.54 D; range, -1.62 to -3.25 D). All patients maintained a spectacle-corrected visual acuity of 20/20 or better during the 12-month study period, with the exception of patient no. 6 who saw 20/30 at the 6-month examination. Her spectacle-corrected visual acuity returned to 20/20 a few days after the ICR was explanted and remained stable throughout the study. Uncorrected visual acuity had improved to 20/40 or better in all patients on postoperative day 1 and remained in this range for the 9 eyes (90%) during the 12 months of follow up. At postoperative month 12, 9 of 9 eyes (100%) had an uncorrected visual acuity of 20/40 or better with 3 of 9 eyes (33%) seeing 20/20 or better. The remaining patient, no. 6, experienced a tear in Descemets membrane during the procedure and required explantation of the ring after 6 months due to induced astigmatism and deterioration of uncorrected visual acuity. Two patients developed infiltrates that resolved with the use of antibiotics. The most common postoperative ocular findings were peripheral corneal haze in all eyes that diminished over time, minute lamellar channel deposits (7 of 10 eyes, 70%), deep stromal neovascularization (5 of 10 eyes, 50%), and pannus (5 of 10 eyes, 50%). CONCLUSION This preliminary study shows that implantation of an intrastromal corneal ring of this dimension (0.3-mm thick) can reduce approximately 1.50 to 3.00 D of myopia and maintain spectacle-corrected visual acuity.

Intrastromal corneal ring--one-year results of first implants in humans: a preliminary nonfunctional eye study.

BACKGROUND The Intrastromal Corneal Ring (ICR) is a new investigational medical device designed to alter corneal curvature without surgical intervention in the central cornea. The ring is inserted between the layers of the stroma in the corneas periphery at two-thirds depth through an approximately 2-millimeter incision. METHODS To investigate the safety and refractive effect of implanting an ICR of a given thickness (0.30 mm) and outer diameter (7.70 mm) into human corneas, an ICR was implanted into one nonfunctional eye of each of three patients during the period of March to May, 1991. One predesignated ICR was successfully explanted 5 months after implantation to evaluate the feasibility of ICR removal and to observe the effect of ring removal on corneal curvature. Patients were followed for 1 year after the initial implant procedure. RESULTS The three implant procedures and postoperative courses proceeded without any significant complications. Approximately 2.00 D of central corneal flattening was achieved in all eyes. No adverse reactions or other medically-significant complications were observed over a 1-year follow-up period. The patient who underwent ICR removal experienced no perioperative complications, and the patients cornea has remained stable with a return to its preoperative curvature. CONCLUSION Although this study is preliminary and limited in scope, we have demonstrated that the ICR can be tolerated safely in the human cornea and results in a flattening of the corneal curvature that is stable for up to a year after insertion. The successful removal of the ICR begins to establish reversibility of the procedure and induced refractive effect.

Limbal and Choroidal Cryptococcus Infection in the Acquired Immunodeficiency Syndrome

PURPOSE A 30-year-old patient with the acquired immunodeficiency syndrome (AIDS) had limbal nodules and multifocal choroidal lesions. METHODS A biopsy of the limbal nodules was performed. RESULTS The biopsy showed Cryptococcus neoformans surrounded by thick mucinous capsules without inflammatory cell infiltration. CONCLUSION In the differential diagnosis of limbal mass in patients with AIDS, cryptococcal infection should be considered.

HERPES ZOSTER PERIPHERAL ULCERATIVE KERATITIS IN PATIENTS WITH THE ACQUIRED IMMUNODEFICIENCY SYNDROME

The purpose of this study was to describe the clinical characteristics and course of peripheral ulcerative keratitis (PUK) secondary to herpes varicella-zoster virus in patients with the acquired immunodeficiency syndrome (AIDS). Three AIDS patients with ocular herpes zoster infection (mean age at onset, 33.0 years; range, 30-42) developed PUK. The three patients had skin involvement, and two of them had bilateral keratouveitis. All were treated with high-dose oral acyclovir (4 g/day) with or without topical antiviral therapy. Two of the patients responded well to oral acyclovir, but one of them stopped the treatment, and bilateral progressive outer retinal necrosis and lethal encephalitis developed. The third patient had a recurrent episode of inflammation with PUK, extensive stromal scarring, and deep neovascularization. AIDS patients with herpes varicella-zoster virus infection may have severe and protracted corneal manifestations, including PUK. The correct diagnosis and aggressive early long-term systemic antiviral treatment must be instituted to control inflammation, ulcer progression, and complications.

Lacrimal Dysfunction in Pediatric Acquired Immunodeficiency Syndrome

In the United States, the Acquired Immunodeficiency Syndrome (AIDS) is the second leading cause of death among men of 25 to 44 years old. By 1987 AIDS had also become the ninth leading cause of death for children between the ages of 1 and 4. It is estimated that one in 75 men and one in 700 women between the ages of 15 and 49 years are infected with human immunodeficiency virus (HIV). Homosexual/bisexual men still account for most cases, but the groups whose numbers are increasing most rapidly include patients exposed through intravenous drug use or heterosexual contact and children infected by perinatal transmission (CDC, 1991).

Avaliaçäo clínica do tratamento cirúrgico da hipercorreçäo pós-ceratotomia radial

Hipermetropia secundaria a ceratotomia radial pode resultar de uma hipercorrecao inicial ou de um efeito continuo da cirugia. Nos avaliamos o efeito do tratamento cirurgico da hipermetropia pos-ceratotomia radial em 5 pacientes (6 olhos) que consistiu em reabertura e lavagem das incisoes radiais, e sutura das mesmas com pontos separados de nailon 10-0. Foram utilizados 4 ou 8 pontos colocados em zonas opticas de 5 e/ou 7 mm. Os pacientes foram acompanhados por um periodo minimo de 24 semanas. Todos os pacientes apresentaram reducao da hipermetropia e melhora da acuidade visual pre-operatoria. O equivalente esferico foi reduzido de 4,87 + ou - 2,02 D para 1,16 + ou - 1,99 D e 2,60 + ou - 0,96 D para 38,02 + ou - 2,39 D e 37,00 + ou - 2,34 D, quatro e 24 semanas apos a cirurgia. Todos os pacientes apresentaram variavel grau de astigmatismo refracional, tambem detectado com a topografia corneana computadorizada. A sutura das incisoes radiais para tratamento da hipercorrecao parece ser um tratamento efetivo para a hipercorrecao apos ceratotomia radial

Perfuraçäo em degeneraçöes ectásicas da córnea

A degeneracao marginal de Terrien, a degeneracao marginal pelucida e o ceratoglobo sao patologias ectasicas da cornea. Essas degeneracoes produzem areas de afinamento periferico que causam ectasia, astigmatismo irregular e maior suscetibilidade a perfuracoes corneanas. Sao apresentados 4 casos de degeneracoes ectasicas com perfuracao corneana (1 casos de ceratoglobo, 2 casos de degeneracao marginal de Terrien, e 1 caso de degeneracao marginal pelucida). O tratamento cirurgico dessas degeneracoes e controverso. As tecnicas descritas sao pouco estudadas devido ao pequeno numero de casos. Geralmente requerem grande habilidade do cirurgiao. As perfuracoes sao complicacoes graves e de dificil manejo. Assim, justificam-se medidas preventivas

Coloraçäo in vivo para o diagnóstico de lesöes neoplásicas e displásicas da conjuntiva

O corante nuclear azul de toluidina, tem sido utilizado com bons resultados no diagnostico e orientacao cirurgica de diversos tumores em mucosas. Atraves da modificacao da tecnica classica de coloracao para uso em conjuntiva ocular, avaliou-se a utilizacao deste corante em lesoes de conjuntiva, na orientacao e complementacao do diagnostico clinico. Quarenta e dois pacientes com lesoes de conjuntiva foram avaliados por exame biomicroscopico simples antes e depois de corados com solucao aquosa de azul de toluidina a 1 por cento e, em seguida, submetidos a biopsia excisional da lesao para comparacao com o exame anatomo-patologico. Dos 42 pacientes, houve concordância em 40 deles (95 por cento) e dois falso-positivos, explicados pela celularidade das lesoes. Todos os diagnosticos de malignidade pelo exame histopatologico foram identificados pelo metodo do azul de toluidina. A analise estatistica mostrou sensibilidade de 100 por cento, especificidade de 94 por cento, valor preditivo positivo de 83 por cento, valor preditivo positivo de 82 por cento, valor preditivo negativo de 100 por cento e chance proporcional de 100 por cento, com significância estatistica determinada pelo teste de McNemar (p=0,25 ou 25 por cento). O uso deste metodo estaria indicado por ser simples, barato, inoquo, e nao necessitar de ambiente cirurgico ou narcose em casos disseminados e em criancas. Alem disso em casos de lesoes grandes e multiplas, sugeriria o local apropriado para biopsia