RESUMO
PURPOSE: Recently laser-in-situ-keratomileusis (LASIK) has been increasingly used to correct refractive errors. The purpose of this investigation was to evaluate the safety, efficacy, predictability, stability and complications using the scanning spot excimer LASIK technology. PATIENTS AND METHODS: The results of 100 consecutive LASIK operations carried out between 2/1998 and 2/1999 on 60 patients (mean age 37 years, range 20-55 years) have been evaluated. The Hansatome microkeratome with a superior hinge (flap diameter: 9.5 mm) and a scanning spot excimer laser (Technolas C-Lasik 217) were used in all cases. The mean spherical equivalent of the subjective manifest refraction was -6.96 +/- 2.87 diopters (D), the mean sphere was -6.47 +/- 2.71 D and the mean astigmatism was -0.98 +/- 0.94 D. In 6% of the eyes preoperative visual acuity was not better than 20/40. Examinations were performed preoperatively, after 1 and 7 days, after 1,4 and 12 months. Safety, efficacy, predictability, stability and complications were calculated using the datagraph software (version 1.11). RESULTS: All 100 eyes were examined after 1 day and 1 week, 96 after 1 month, 95 after 4 months and 92 after 1 year. Following 1 year none of the eyes lost 2 or more lines of best corrected visual acuity, 99% were within +/- 1 line and 1% gained 2 lines (safety index 1.03). In 92% of all eyes an uncorrected visual acuity of > or = 0.5 was reached, in 77% > or = 0.8 and in 51% > or = 1.0 (efficacy index 0.89). For 60 eyes (65.21%) a refractive correction of +/- 0.5 D was necessary, for 82 eyes (89.13%) +/- 1.0 D and for 91 eyes (98.91%) +/- 2.0 D. The mean spherical equivalent after 1 year was -0.15 +/- 1.31 D. Between 1 and 12 months a mean regression of -0.14 D occurred. On the request of the patients, 5 eyes were retreated during the study period for under- or over-correction. Complications due to the microkeratome did not occur. Corneal infections were not observed, a diffuse lamellar keratitis (DLK) was seen in 12 cases, but all cases healed with no loss of visual acuity. In 7 eyes a slight decentration of the ablation was observed using corneal topography, which in one case caused an increase in glare sensitivity. CONCLUSIONS: LASIK with superior hinge and scanning spot excimer photoablation is suitable for the correction of myopia (up to a maximum of -12 D) and for myopic astigmatism (up to a maximum of -5 D). The refractive results showed a high stability during the 12-month study period but there is still room for improvement of the predictability.
Assuntos
Astigmatismo/cirurgia , Ceratomileuse Assistida por Excimer Laser In Situ , Miopia/cirurgia , Adulto , Fatores Etários , Seguimentos , Humanos , Complicações Intraoperatórias , Ceratomileuse Assistida por Excimer Laser In Situ/efeitos adversos , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Estudos Prospectivos , Fatores de TempoRESUMO
BACKGROUND: An alarming incidence (1% to 83%) of neuropsychological dysfunction has been reported after operations using cardiopulmonary bypass (CPB). The present clinical study re-evaluates these complications with current CPB technology in a strictly selected low-risk group of coronary artery bypass (CABG) patients. METHODS: 76 CABG patients, without history of stroke or internal carotid artery stenosis, were examined before, 5 days after, and 2 months after surgery. A neuropsychological test battery was employed according to the "Statement of Consensus on Assessment of Neurobehavioral Outcomes after Cardiac Surgery". Tests include the Block Design Test (problem-solving strategies, recognition and analysis of forms), the Trail Making Test (cognitive achievement at speed), and the Digit Span Test (short-term memory and memory of figures). RESULTS: Both postoperative test scores were not significantly decreased as compared to preoperative values. In contrast, neuron specific enolase (NSE) and S100 b protein, biochemical markers of cerebral injury, increased markedly during and immediately after surgery (NSE preop.: 7.07 +/- 2.40 ng/ml, 1 h postop.: 13.64 +/- 4.50 ng/ml, p < 0.001; S100 b preop.: 0.04 +/- 0.07 ng/ml, after crossclamp: 0.90 +/- 0.69 ng/ml, p < 0.001). One patient displayed postoperative transitional syndrome, another patient suffered from transitory paresis and hypesthesia of the left arm, which disappeared during hospital stay. CONCLUSIONS: Biochemical markers demonstrate significant postoperative cerebral injury during and immediately after CPB. However, CPB for CABG does not lead to marked impairment of neuropsychological scores, and clinically relevant neurological findings were observed in one patient only.