RESUMO
BACKGROUND: Globally, diabetes is increasing with concerns about the impact on outcomes, including premature death and the costs associated with managing the condition. Research indicates that adults with intellectual disabilities (ID) are two to three times more likely to develop diabetes; however, there has been limited focus on diabetes service utilisation in this population. The aim of this study is to explore the perceptions and experiences of diabetes and ID practitioners. METHODS: A series of 1:1 semi-structured interviews were undertaken in one Scottish health service area. In total, 29 qualitative interviews were conducted: 10 with diabetes practitioners from primary and secondary care, 14 from ID services and 5 from community care services regarding diabetes service provision for this population. Thematic content analysis was undertaken to identify the themes and subthemes. RESULTS: Three main themes were identified: (1) enabling access to services to meet diabetes-related care needs of people with ID; (2) communication and service improvements between staff, patients and across services; and (3) providing person-centred diabetes care and developing adapted resources to increase patient self-care. CONCLUSIONS: The findings of this study have important international implications in how diabetes practitioners plan and deliver services for people with ID and other vulnerable groups with limited cognitive ability and communication skills and difficulties in self-management. The findings highlight that access to diabetes education and adapted resources is needed, and if 'reasonable adjustments' are made to service provision and practice, people with ID can benefit from improved healthcare. Developing joint clinics to share knowledge and resources between diabetes and ID practitioners may improve service delivery and continuity of care, and thereby diminish the costs of not providing quality care.
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Atitude do Pessoal de Saúde , Diabetes Mellitus/terapia , Acessibilidade aos Serviços de Saúde/estatística & dados numéricos , Acessibilidade aos Serviços de Saúde/normas , Deficiência Intelectual/terapia , Comorbidade , Diabetes Mellitus/epidemiologia , Humanos , Deficiência Intelectual/epidemiologia , Pesquisa Qualitativa , EscóciaRESUMO
Barrett's esophagus is a pre-malignant lesion that can progress to esophageal adenocarcinoma. We perform a multi-omic analysis of pre-cancer samples from 146 patients with a range of outcomes, comprising 642 person years of follow-up. Whole genome sequencing reveals complex structural variants and LINE-1 retrotransposons, as well as known copy number changes, occurring even prior to dysplasia. The structural variant burden captures the most variance across the cohort and genomic profiles do not always match consensus clinical pathology dysplasia grades. Increasing structural variant burden is associated with: high levels of chromothripsis and breakage-fusion-bridge events; increased expression of genes related to cell cycle checkpoint, DNA repair and chromosomal instability; and epigenetic silencing of Wnt signalling and cell cycle genes. Timing analysis reveals molecular events triggering genomic instability with more clonal expansion in dysplastic samples. Overall genomic complexity occurs early in the Barrett's natural history and may inform the potential for cancer beyond the clinically discernible phenotype.
Assuntos
Esôfago de Barrett , Neoplasias Esofágicas , Esôfago de Barrett/genética , Esôfago de Barrett/patologia , Estudos de Coortes , Estudos Transversais , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/patologia , Humanos , Retroelementos/genéticaRESUMO
Spleen lymphocytes taken from mice at various stages of pregnancy or growth of s.c. syngeneic tumor implants have been examined for their ability to cause cytolysis of embryo fibroblasts in culture or to affect the growth of the transplanted tumor cells in vivo. Activity of different lymphoid populations in affecting tumor growth in vivo was correlated with activity in vitro, whether cytolysis (growth inhibition) or blocking of cytolysis (growth promotion) was considered. The evidence favors an important role for lymphoid responses to embryo-associated antigens in the control of spontaneous tumor growth, although one cannot yet rule out a crucial role for the host milieu rather than, or in addition to, host cellular elements being the important feature of this control process.
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Linfócitos/imunologia , Neoplasias Mamárias Experimentais/imunologia , Animais , Antígenos de Neoplasias , Células Cultivadas , Citotoxicidade Imunológica , Embrião de Mamíferos , Feminino , Idade Gestacional , Masculino , Neoplasias Mamárias Experimentais/sangue , Neoplasias Mamárias Experimentais/patologia , Camundongos , Camundongos Endogâmicos C3H , Transplante de Neoplasias , Gravidez , Baço/citologia , Baço/imunologia , Fatores de TempoRESUMO
Identification of risk factors which are associated with severe clinical signs can assist in the management of disease outbreaks and indicate future research areas. Pregnancy loss during late gestation in the mare compromises welfare, reduces fecundity and has financial implications for horse owners. This retrospective study focussed on the identification of risk factors associated with pregnancy loss among 46 Thoroughbred mares on a single British stud farm, with some but not all losses involving equid herpesvirus-1 (EHV-1) infection. In a sub-group of 30 mares, association between pregnancy loss and the presence of five common Thoroughbred horse haplotypes of the equine Major Histocompatibility Complex (MHC) was assessed. This involved development of sequence specific, reverse transcriptase polymerase chain reactions and in several mares, measurement of cytotoxic T lymphocyte activity. Of the 46 mares, 10 suffered late gestation pregnancy loss or neonatal foal death, five of which were EHV-1 positive. Maternal factors including age, parity, number of EHV-1 specific vaccinations and the number of days between final vaccination and foaling or abortion were not significantly associated with pregnancy loss. In contrast, a statistically significant association between the presence of the MHC class I B2 allele and pregnancy loss was identified, regardless of the fetus/foal's EHV-1 status (p=0.002). In conclusion, this study demonstrated a significantly positive association between pregnancy loss in Thoroughbred mares and a specific MHC class I allele in the mother. This association requires independent validation and further investigation of the mechanism by which the mare's genetic background contributes to pregnancy outcome.
Assuntos
Aborto Animal/genética , Alelos , Antígenos de Histocompatibilidade Classe I/genética , Doenças dos Cavalos/genética , Cavalos/genética , Animais , Feminino , Humanos , Morte Perinatal , Gravidez , Estudos Retrospectivos , Linfócitos T Citotóxicos/metabolismoRESUMO
Assays of first morning urine samples for pregnanediol-3 alpha-glucuronide (PdG), estradiol-17 beta-glucuronide (E2G), and LH were used to monitor endocrine function in 16 regularly cycling women and 22 postpartum nonbreastfeeding women. Twice weekly blood samples were also obtained from the postpartum group. Ovulation was inferred by a significant rise in LH and PdG, and reversal of the E2G to PdG ratio. Luteal phase PdG excretion was measured by the peak of smoothed PdG levels and the area under the smoothed luteal phase PdG curve. The lower limits of normal established in 16 cycling women were a peak luteal phase PdG of 4 micrograms/ml and an area under the PdG curve of 20 micrograms/ml. In the postpartum women, 32% of first cycles were anovulatory, and among ovulatory cycles, 73% had abnormally low luteal phase PdG excretion or short luteal phases. In second and subsequent cycles, 15% were anovulatory and 26% had luteal phase abnormalities. There was a progressive increase in luteal PdG excretion from the first to third cycles. The mean delay before first ovulation was 45.2 days, and no woman ovulated before 25 days after delivery. The correlations between blood and urinary hormone levels were 0.78 for PdG, 0.65 for E2G, and 0.55 for LH. We conclude that assays of daily early morning urine samples provide reliable information on ovulation and luteal phase adequacy, and that there is gradual recovery of pituitary ovarian function after parturition.
Assuntos
Estradiol/análogos & derivados , Fase Luteal , Período Pós-Parto/fisiologia , Pregnanodiol/análogos & derivados , Adulto , Estradiol/sangue , Estradiol/urina , Feminino , Humanos , Hormônio Luteinizante/metabolismo , Ovulação , Período Pós-Parto/urina , Gravidez , Pregnanodiol/urina , Progesterona/sangueRESUMO
Wide-field specular microscopy and computer-assisted morphometry were performed on 20 aphakic eyes in 16 patients who had worn a high-water content hydrogel contact lens on an extended wear basis for at least 12 months (mean, 28 months) following intracapsular cataract extraction. When compared with 22 non-lens-wearing aphakic eyes matched for age and postoperative period, the endothelial cell changes in the above patients included a significantly higher coefficient of variation in cell area (polymegathism) and a marked reduction in the frequency of hexagonal cells (pleomorphism) without any significant difference in cell density. Although the clinical significance of these endothelial changes remains unclear, they may indicate hypoxic stress to the corneal endothelium or be an early sign of ongoing cell loss.
Assuntos
Afacia Pós-Catarata/terapia , Lentes de Contato de Uso Prolongado/efeitos adversos , Lentes de Contato Hidrofílicas/efeitos adversos , Endotélio Corneano/patologia , Idoso , Afacia Pós-Catarata/patologia , Contagem de Células , Humanos , Pessoa de Meia-IdadeRESUMO
Goldmann tonometer tips were inoculated with 5 X 10(5) IU of cell-free or cell-associated human immunodeficiency virus type 1 (lymphadenopathy virus type 1 isolate) or 10(4) plaque-forming units of herpes simplex virus type 1 (McKrae strain) or type 2 (Hicks strain). In an effort to mimic a "worst case" clinical scenario, each respective virus was allowed to air dry on the tonometer tip for 10 minutes. Inoculated tonometers were then (1) not treated, (2) wiped with a disposable (Kim-wipe) tissue or sterile gauze; (3) wiped with sterile gauze soaked with 3% hydrogen peroxide; or (4) wiped with a 70% isopropyl alcohol swab. The hydrogen peroxide treatment and the alcohol wipes both completely disinfected the tonometer tips for human immunodeficiency virus type 1 and herpes simplex virus types 1 and 2, whereas wiping with a sterile gauze or tissue was not effective. Wiping the Goldmann tonometer tip with an isopropyl alcohol swab and then allowing the alcohol to evaporate provides a ready and efficient means of inactivating these three enveloped viruses.
Assuntos
1-Propanol/uso terapêutico , Desinfecção/métodos , HIV-1 , Peróxido de Hidrogênio/uso terapêutico , Simplexvirus , Esterilização/métodos , Tonometria Ocular/instrumentação , 1-Propanol/administração & dosagem , Antígenos HIV/análise , HIV-1/efeitos dos fármacos , HIV-1/enzimologia , HIV-1/isolamento & purificação , Peróxido de Hidrogênio/administração & dosagem , Ativação Linfocitária , Linfócitos , DNA Polimerase Dirigida por RNA/metabolismo , Simplexvirus/efeitos dos fármacos , Simplexvirus/isolamento & purificaçãoRESUMO
We tested eight patients who had undergone radial keratotomy with regard to refraction, keratometry, corneal thickness, and intraocular pressure one to two weeks after surgery. Patients were examined immediately after eye-lid opening at 7:30 A.M. and again at 4:00 P.M. The contralateral eye was used as a control. The treated eye was 1.48 +/- 0.24 diopters (mean +/- S.E.M.) more hyperopic at the morning examination compared to the afternoon visit, whereas the control eye had an insignificant shift (0.16 +/- 0.06 diopters). The treated eye was significantly flatter (1.37 +/- 0.19 diopters) in the morning than in the afternoon when compared to the control eyes, which were only 0.11 +/- 0.09 diopter flatter. The intraocular pressure changed insignificantly in both the treated and control eyes (-0.5 +/- 0.53 mm Hg and -0.5 +/- 0.84 mm Hg, respectively). The mean morning corneal thickness was significantly greater (5.7%) than the afternoon thickness when compared to the controls (1.7% morning increase in thickness). These data suggest that diurnal variation in corneal thickness after radial keratotomy plays a role in diurnal variation of vision in the early postoperative period.
Assuntos
Ritmo Circadiano , Ceratotomia Radial , Visão Ocular/fisiologia , Adulto , Humanos , Ceratotomia Radial/métodos , Período Pós-OperatórioRESUMO
Using wide-field specular microscopy, we evaluated the morphologic features of the corneal endothelium in 14 eyes of 14 patients with keratoconus who had worn a polymethylmethacrylate hard contact lens for at least four years (mean, 71 months) after penetrating keratoplasty. Comparisons were made with 14 non-lens-wearing eyes of 14 patients with keratoconus matched for age, length of postoperative period, and other variables. Examination of the endothelium of the contact lens wearers showed a significantly higher coefficient of variation in cell size (polymegethism) and a marked decrease in the percentage of hexagonal cells (pleomorphism), with a significant decrease in cell density (P less than .05). The cause of these morphologic abnormalities remains unclear but may be related to lens-induced hypoxic stress to the corneal endothelium causing ongoing cell loss.
Assuntos
Lentes de Contato/efeitos adversos , Transplante de Córnea , Endotélio Corneano/patologia , Ceratocone/terapia , Contagem de Células , Humanos , Ceratocone/patologia , Metilmetacrilatos , Período Pós-OperatórioRESUMO
Four corneas from two cadavers that later had positive test results on enzyme-linked immunosorbent assays and Western blot analysis for antibodies against the human immunodeficiency virus were inadvertently transplanted to recipients who were without known risk of human immunodeficiency virus infection. We performed serial studies of serologic markers of human immunodeficiency virus infection in the cornea recipients and assayed reverse transcriptase levels of their mixed lymphocyte cultures. The four cornea transplant recipients were followed up for 130, 152, 397, and 440 days, respectively, and the results on all serologic tests and reverse transcriptase assays remain negative.
Assuntos
Síndrome da Imunodeficiência Adquirida/diagnóstico , Transplante de Córnea , Testes Sorológicos , Doadores de Tecidos , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
We analyzed clinical data on 22,739 contact lens wearers who were studied and whose lenses were approved under 48 manufacturer-sponsored studies for the Food and Drug Administration between 1980 and 1988. The incidence of corneal ulcers was low in the cosmetic (nontherapeutic) daily-wear soft and rigid gas-permeable lens wearers (1/1,923 and 1/1,471 patient-years, respectively). Corneal ulcers and severe adverse reactions occurred two to four times more frequently in extended-wear cosmetic soft and rigid gas-permeable lens wearers than in cosmetic daily-wear lens wearers. Aphakic extended-wear soft lens users were nine times more likely to develop a corneal ulcer when compared to the soft daily-wear cosmetic group. Corneal abrasions and keratitis accounted for 81 of 159 severe adverse reactions, whereas corneal ulcers accounted for 28 of 159 adverse reactions. The data indicate that overnight extended wear of contact lenses is associated with a greater risk of serious, sight-threatening complications than daily wear.
Assuntos
Lentes de Contato de Uso Prolongado , Lentes de Contato Hidrofílicas/efeitos adversos , Úlcera da Córnea/etiologia , Afacia/complicações , Doenças da Córnea/etiologia , Humanos , Incidência , Ceratite/etiologia , Estados Unidos , United States Food and Drug AdministrationRESUMO
PURPOSE: To present the approach of using a scanning slit refractometer (the ARK 10000) in conjunction with a corneal topography system to guide customized corneal ablation. This diagnostic system is coupled with the Nidek EC-5000 system which combines scanning slit and a scanning small area ablation (1.0 mm) to perform a customized ablation. METHODS: The ARK 10000 diagnostic system which contains a scanning slit refractometer is described. Information generated from the ARK 10000 wavefront sensor and corneal topography system can be coupled to the new Nidek EC-5000 excimer laser system, which combines the larger area of scanning slit ablation with the small area (1.0 mm) ablation. RESULTS: The Nidek ARK 10000 diagnostic system captures wavefront information using a retinoscopic system which is converted into a refractive power map. This is different from other autorefraction systems in that it has four sensors at different diameters of the cornea and captures 1440 points in 0.4 seconds. This map is used in conjunction with corneal topography-captured simultaneously. This information is then combined to perform a customized ablation using the new Nidek EC-5000 system. CONCLUSIONS: The ARK 10000 diagnostic system represents a different approach to customized ablation in that it combines a corneal topography system with a wavefront system and a larger treatment area of the traditional scanning slit ablation with a new small area ablation treatment for greater efficiency.
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Córnea/patologia , Hiperopia/diagnóstico , Lasers , Miopia/diagnóstico , Refração Ocular , Acomodação Ocular , Córnea/cirurgia , Topografia da Córnea , Humanos , Hiperopia/cirurgia , Lasers de Excimer , Miopia/cirurgia , Ceratectomia FotorrefrativaRESUMO
BACKGROUND: The long-term effects of radial keratotomy on the corneal endothelium are not well understood. We evaluated the effects of radial keratotomy on the corneal endothelium on the central and midperipheral corneal endothelium. METHODS: Anterior radial keratotomy in 25 eyes was performed and patients were followed for a duration of 4 to 10 years after surgery. Eleven non- contact lens wearing control eyes did not have surgery and were followed for the same period. Morphometric analysis of specular microscopic images was performed with regard to cell density, percent hexagonality, and coefficient of variation. RESULTS: Mean corneal endothelial cell loss rates were 0.4% per year in the radial keratotomy group and 0.9% in the untreated control group over the study duration (mean 7 yr). Morphometric analysis of the cells failed to show a significant change in hexagonality and coefficient of variation. Evaluation of the midperipheral corneal cell counts demonstrated a 1% per year cell loss rate. The cell loss rates in radial keratotomy patients followed over this period were consistent with that noted for normal aging (0.5 to 2.5% per year). CONCLUSION: Radial keratotomy does not cause accelerated endothelial cell loss over 4 to 10 years.
Assuntos
Córnea/cirurgia , Endotélio Corneano/citologia , Ceratotomia Radial , Procedimentos Cirúrgicos Refrativos , Adulto , Envelhecimento , Contagem de Células , Seguimentos , Humanos , Pessoa de Meia-Idade , Estudos ProspectivosRESUMO
PURPOSE: To review the early development of new technologies that are becoming available through customized corneal ablation techniques. METHODS: The authors describe the early development of two diagnostic methods to perform customized corneal ablation as well as a variety of new treatment modalities in development. RESULTS AND CONCLUSION: Results using the wavefront sensors indicate that these techniques have the potential to be more sensitive than traditional refraction and keratometry. Subtle defects such as coma and spherical aberration can be detected and treated. A whole series of new technologies are being incorporated to treat patients with customized corneal ablation. [J Refract Surg 2000;16(suppl):S230-S235].
RESUMO
PURPOSE: The purpose of this study was to use the Arizona Eye Model to help guide customization of corneal excimer ablation and reduce spherical aberration. METHODS: Myopic eyes were treated with the Nidek EC-5000 excimer laser with a 5.5-mm diameter optic ablation zone and a 7.0-mm diameter transition ablation zone. We analyzed preoperative and postoperative corneal topographies using height mapping. From this data, refractive error profiles and maps were constructed using the Arizona Eye Model. The first group of patients had refractions between -2.00 and -5.00 D. Data was obtained by subtracting postoperative topography from preoperative topography. We then plotted the ideal ablation pattern if no additional spherical aberration was introduced when compared to preoperative topographies. RESULTS: We found that in the central 4 mm, the ablation pattern was highly acceptable, with negligible spherical aberration. As the ablation moved out toward 6 mm, there was increasing spherical aberration. Newer ablation designs require more flattening in the midperiphery of the cornea. These flatter peripheral designs require more blending in the periphery and larger transition zones. CONCLUSION: The use of computerized corneal topography in eye modeling is helpful in designing new ablation patterns to reduce optical and spherical aberration. Ablation zone design is critical to maximizing optical and biologic tolerance.
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Astigmatismo/prevenção & controle , Córnea/cirurgia , Miopia/cirurgia , Ceratectomia Fotorrefrativa/métodos , Astigmatismo/patologia , Córnea/patologia , Topografia da Córnea/métodos , Humanos , Lasers de Excimer , Modelos Biológicos , Miopia/patologia , Refração Ocular , Resultado do Tratamento , Acuidade VisualRESUMO
PURPOSE: To illustrate a case in which sterile interface keratitis after laser in situ keratomileusis (LASIK) occurred concomitantly with an allergic contact dermatitis of the eyelids. METHODS: Retrospective case review. RESULTS: Resolution of the interface keratitis and dermatitis occurred following an intense course of topical corticosteroids and brief course of oral corticosteroids. Despite an attempt to eliminate potential causes, the same patient developed interface keratitis in the fellow eye following both the initial LASIK and an enhancement, in which no microkeratome was used. Intense treatment with both topical and oral corticosteroids led to a final uncorrected visual acuity of 20/20 in the right eye and 20/25+2 in the left eye. CONCLUSION: The etiology and mechanism of sterile interface keratitis after LASIK are unknown, but are probably multifactorial. The concomitant contact dermatitis reaction may indicate a common immune mechanism.
Assuntos
Dermatite Alérgica de Contato/etiologia , Doenças Palpebrais/etiologia , Ceratite/etiologia , Ceratomileuse Assistida por Excimer Laser In Situ/efeitos adversos , Complicações Pós-Operatórias , Adulto , Astigmatismo/cirurgia , Humanos , Masculino , Estudos RetrospectivosRESUMO
BACKGROUND: Donor cornea contamination as a cause of endophthalmitis is one of the most serious complications of penetrating keratoplasty. Optisol-GS corneal storage medium with the combination of gentamicin and streptomycin was designed to provide wider antibiotic coverage, most notably against streptococcal species. However, many enterococci are resistant to streptomycin and genta micin. METHODS/RESULTS: We report a case in which Enterococcus faecium was isolated from cultures of the donor limbus prior to corneal excision and again from preoperative cultures of the donor corneal rim despite 5 days of preservation in Optisol-GS. The isolate was found to be resistant to both gentamicin and streptomycin. CONCLUSIONS: This case illustrates the need to raise awareness that streptococcus can remain a viable contaminant of donor corneas despite storage in Optisol-GS medium.
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Córnea/microbiologia , Meios de Cultura Livres de Soro , Enterococcus faecium/crescimento & desenvolvimento , Infecções Oculares Bacterianas , Preservação de Órgãos , Sulfatos de Condroitina , Misturas Complexas , Dextranos , Gentamicinas , Humanos , Masculino , Pessoa de Meia-Idade , Doadores de TecidosRESUMO
PURPOSE: To assess the efficacy and safety of a combined ablation of the steep and flat meridian to correct astigmatism with the excimer laser. METHODS: Twenty-two eyes with myopic, mixed, or hyperopic astigmatism (mean preoperative spherical equivalent refraction -4.30 +/- 4.70 D [range, -12.50 to +1.50 D] and mean preoperative cylinder magnitude -3.40 +/- 1.40 D [range, -1.50 to -6.00 D]) underwent PRK with the Nidek EC-5000 excimer laser. The surgical strategy involved ablating half the amount of the cylinder (in diopters) along steepest meridian, the other half in a subsequent step along the flattest meridian; thereafter, the spherical equivalent was corrected. RESULTS: Six months postoperatively, mean spherical equivalent refraction was -0.07 +/- 0.87 D and mean cylinder was -0.44 +/- 0.36 D. Mean spectacle-corrected visual acuity was 0.86 +/- 0.13 compared to 0.75 +/- 0.22 preoperatively. Mean corneal haze was 0.67 +/- 0.31. No patient lost 2 or more lines of spectacle-corrected visual acuity and there were no complaints about night halos or glare. CONCLUSIONS: Unlike other ablation strategies, the cross-cylinder method creates a smooth transition (low dioptric gradient) between the treated and untreated cornea. This is achieved by first treating the cylinder and making the corneal surface spherical and then ablating the spherical component of the refractive error.
Assuntos
Astigmatismo/cirurgia , Córnea/cirurgia , Hiperopia/cirurgia , Miopia/cirurgia , Ceratectomia Fotorrefrativa/métodos , Adulto , Astigmatismo/complicações , Córnea/patologia , Seguimentos , Humanos , Hiperopia/complicações , Lasers de Excimer , Pessoa de Meia-Idade , Miopia/complicações , Refração Ocular , Reprodutibilidade dos Testes , Segurança , Resultado do Tratamento , Acuidade VisualRESUMO
PURPOSE: Photoastigmatic refractive keratectomy (PARK) was studied in a multi-center clinical trial. The Nidek EC-5000 excimer laser was evaluated for its effect on refraction, visual acuity, and safety measures as part of a U.S. Food and Drug Administration (FDA) regulated study. METHODS: Eight U.S. centers enrolled adults with eyes having refractive astigmatism up to 4.00 D and a myopic spherical equivalent refraction up to -8.00 D. Results are reported for 749 eyes of 486 patients with at least 6 months follow-up. The rectangular beam scanning Nidek EC-5000 used a 5.5-mm-diameter treatment zone, a 7.0-mm-diameter peripheral blend zone, and a 40 Hz pulse rate for surface treatment of myopic astigmatism. Nomogram corrections to machine settings were required to achieve the desired results. RESULTS: Preoperative average spherical equivalent refraction of -4.90+/-1.74 D was reduced to -0.02+/-0.79 D at 6 months. Refractive stability was established at 3 months. Over 62% of eyes were within +/-0.50 D of desired correction at 6 months, with over 86% within +/-1.00 D. Uncorrected visual acuity improved by an average of 10 Snellen lines; over 64% of eyes saw 20/20 or better uncorrected and over 93% saw 20/40 or better uncorrected at 6 and 12 months. PARK treatment effectively reduced astigmatism with little average axis error or magnitude error. Corneal haze and safety concerns were minimal. CONCLUSIONS: Photoastigmatic refractive keratectomy using the Nidek EC-5000 excimer laser provided significant reduction of myopia and astigmatism, with minimal complications.
Assuntos
Astigmatismo/cirurgia , Córnea/cirurgia , Miopia/cirurgia , Ceratectomia Fotorrefrativa , Adulto , Idoso , Astigmatismo/fisiopatologia , Córnea/fisiopatologia , Feminino , Humanos , Lasers de Excimer , Masculino , Pessoa de Meia-Idade , Miopia/fisiopatologia , Satisfação do Paciente , Refração Ocular , Segurança , Resultado do Tratamento , Acuidade VisualRESUMO
PURPOSE: To describe the rationale behind elliptical and other transition designs used with the excimer laser. SETTING: Casey Eye Institute, Oregon Health Sciences University, Portland, Oregon, USA. METHODS: Ablation zone designs were analyzed for the number of transition points for myopia and hyperopia. The advantages and disadvantages of elliptical transition zones are demonstrated graphically, with an emphasis on smooth ablation zone design to maximize the optics and biologic tolerance by the eye. RESULTS: The use of an individualized elliptical transition maximizes a circular effective optical zone and can enhance the smoothness of the transition zone while minimizing excessive tissue removal. CONCLUSION: Elliptical transition zones may improve the optics and biologic tolerance of excimer laser treatments.