Biomedical subjects

Wen-Ming Hsu

Publications and source records attributed to Wen-Ming Hsu.

At least 37 records · Page 2Linked to original sources

PubMed2006

Different plasma levels of vascular endothelial growth factor and nitric oxide between patients with choroidal and retinal neovascularization.

Because the blood flow is much more intense in the choroid than in the retina, it is interesting to explore whether choroidal neovascularization (CNV) is more influenced by plasma angiogenic factors than retinal neovascularization. The aim of this study was to investigate plasma profiles of vascular endothelial growth factor (VEGF) and nitric oxide (NO) in patients with CNV due to age-related macular degeneration (AMD) and in those with retinal neovascularization due to proliferative diabetic retinopathy (PDR). Seventy-seven subjects with AMD, 22 with PDR, and 42 nondiabetic, non-AMD controls were enrolled in this comparative case series. AMD subjects were classified into three groups: dry type (dry AMD, n = 17), wet type with active CNV (CNV/AMD, n = 42), and disciform scar due to advanced wet AMD (scar/AMD, n = 18). Plasma VEGF and NO levels of each subject were measured with enzyme-linked immunosorbent assay and chemiluminescence, respectively. Plasma VEGF level in CNV/AMD (median 256.0 pg/ml, interquartile range 146.4-375.3 pg/ml) was significantly higher than in PDR (124.8 pg/ml, 75.7-215.3 pg/ml; p = 0.004) and controls (120.3 pg/ml, 82.8-168.2 pg/ml, p =0.001). CNV/AMD also had the highest VEGF level among the AMD subgroups. Plasma NO level was significantly elevated in PDR (137.4 microM, 63.7-240.1 microM) when compared with CNV/AMD (71.8 microM, 42.4-113.3 microM; p = 0.004) and controls (62.6 microM, 39.0-114.9 microM; p = 0.002). There was no significant difference in NO levels among the AMD subgroups. No significant correlation between VEGF and NO levels was noted. These findings indicate that both circulating VEGF and NO may play different roles in the pathogenesis of retinal neovascularization and CNV.

Aged↗

PubMed2006

Association of the Y402H polymorphism in complement factor H gene and neovascular age-related macular degeneration in Chinese patients.

PURPOSE: Age-related macular degeneration (AMD), with its complex traits and multiple risk factors, is the leading cause of blindness in the elderly. A strong association between a coding variant, Y402H, in the complement factor H gene (CFH) and AMD has been recently identified in white patients. This study was conducted to investigate the association between the Y402H polymorphism in CFH and neovascular AMD in Chinese patients. METHODS: One hundred sixty-three Chinese patients with neovascular AMD and 232 age-matched healthy controls were enrolled in the study. Genomic DNA from white blood cells was extracted. The Y402H polymorphism in CFH, with the substitution of T to C at nucleotide position 1277 in exon 9, was determined by polymerase chain reaction-restriction fragment length polymorphism analysis. The association between the genetic polymorphism and the disease was examined by chi(2) test and logistic regression. RESULTS: The frequency of the risk allele, 1277C, was 11.3% in AMD patients compared with 2.8% in controls (P < 0.00001). Genotype frequency differed significantly between the two groups (1277TT 81.0%, 1277TC 15.3%, and 1277CC 3.7% in the AMD group; 1277TT 94.4%, 1277TC 5.6%, and 1277CC 0% in the control group; P < 0.0001). The 1277C allele significantly increased the risk for neovascular AMD and had an odds ratio of 4.4 (95% confidence interval [95% CI], 2.3-8.5; P < 0.00001). CONCLUSIONS: The allele frequency of Y402H polymorphism in CFH has an ethnic variation, with much lower 1277C frequency in Chinese than in white patients. Despite this, the polymorphism is significantly associated with neovascular AMD in the Chinese population.

Aged↗

PubMed2006

Herpes simplex keratitis following excimer laser application.

PURPOSE: To report two cases of herpes simplex keratitis following excimer laser application. METHODS: Two immunocompetent patients with no history of ocular viral infection developed ulcers after LASIK and phototherapeutic keratectomy (PTK), respectively. RESULTS: Antiviral treatment was administered, and the lesions healed within 14 days. CONCLUSIONS: These two cases suggest that herpes simplex virus was associated with the use of the excimer laser.

Adult↗

PubMed2005

Fecal elastase 1, serum amylase and lipase levels in children with cholestasis.

BACKGROUND/AIM: The pancreatic functions of children with cholestatic liver diseases were unclear. Due to anatomic vicinity and common ontogenic origin, hepatobiliary disorders of infancy may also affect pancreatic function. The aim of the study was to evaluate the exocrine pancreatic function and common pancreatic function tests in children with cholestatic disorders. METHODS: In 40 children with cholestasis, fecal elastase 1 (FE1) concentrations were measured. Serum amylase and lipase values were tested. The diagnoses included 32 patients with extrahepatic cholestasis (biliary atresia (BA) and choledochal cyst), and 8 patients with intrahepatic cholestasis (progressive familial intrahepatic cholestasis and Alagille syndrome). None had renal insufficiency or clinical symptoms/signs of acute pancreatitis. RESULTS: All the patients had normal FE1 (>200 microg/g). Nineteen percent (7/37) had elevated serum amylase levels (>100 U/l). Thirty-two percent (12/37) had elevated serum lipase levels above the normal (>120 U/l). Seventy-three percent (8/11) of BA patients with bilirubin >2 mg/dl had elevated serum lipase levels compared to 18% (3/17) with bilirubin < or = 2 mg/dl (p = 0.0036). None had detectable pancreatic abnormality on ultrasonography and magnetic resonance images. CONCLUSIONS: None of the cholestatic children in this study had exocrine pancreatic insufficiency as detected by FE1. Hyperamylasemia and/or hyperlipasemia were frequently found. In children with BA, those with impaired biliary excretion tended to have elevated serum pancreatic enzymes as compared with those who had no jaundice. A decreased hepatic metabolism may be the cause.

Alagille Syndrome↗

PubMed2005

GRP78 expression correlates with histologic differentiation and favorable prognosis in neuroblastic tumors.

Glucose-regulated protein 78 (GRP78), an endoplasmic reticulum protein, is essential for the differentiation of neuroblastoma cells and is selectively induced when the cells are undergoing apoptosis. These findings suggest that GRP78 may affect the tumor behavior of neuroblastoma. Our study evaluates the association of clinicopathologic factors and patient survival with the expression of GRP78 in patients with neuroblastoma. GRP78 expression in 68 neuroblastic tumors was investigated semiquantitatively by immunohistochemistry. GRP78 mRNA and protein levels in 7 tumor tissues were also quantified by real-time PCR and Western blot respectively and correlated well with the immunohistochemical results. Forty (58.8%) of the 68 neuroblastic tumors showed positive GRP78 expression. The percentage of positive GRP78 immunostaining increased as the tumor histology became differentiated (p = 0.001). Furthermore, positive GRP78 expression strongly correlated with early clinical stages (P = 0.002) but inversely correlated with MYCN amplification (p = 0.001). Kaplan-Meier analysis showed that patients with positive GRP78 expression did have better survival than those with negative expression (5-year survival rate, 72.9% and 23.4% respectively, p < 0.001). Multivariate analysis further showed that GRP78 expression was an independent prognostic factor. Moreover, GRP78 expression predicted better survival in patients with either undifferentiated or differentiated histologies. GRP78 expression still had significant prognostic value when the analysis was restricted to tumors of advanced stages or without MYCN amplification. Thus, GRP78 can serve as a novel independent favorable prognostic factor for patients with neuroblastoma.

Base Sequence↗

PubMed2005

A novel in vitro retinal differentiation model by co-culturing adult human bone marrow stem cells with retinal pigmented epithelium cells.

Human retinal pigment epithelium (HRPE) cells are important in maintaining the normal physiology within the neurosensory retina and photoreceptors. Recently, transplantation of HRPE has become a possible therapeutic approach for retinal degeneration. By negative immunoselection (CD45 and glycophorin A), in this study, we have isolated and cultivated adult human bone marrow stem cells (BMSCs) with multilineage differentiation potential. After a 2- to 4-week culture under chondrogenic, osteogenic, adipogenic, and hepatogenic induction medium, these BMSCs were found to differentiate into cartilage, bone, adipocyte, and hepatocyte-like cells, respectively. We also showed that these BMSCs could differentiate into neural precursor cells (nestin-positive) and mature neurons (MAP-2 and Tuj1-positive) following treatment of neural selection and induction medium for 1 month. Furthermore, the plasticity of BMSCs was confirmed by initiating their differentiation into retinal cells and photoreceptor lineages by co-culturing with HRPE cells. The latter system provides an ex vivo expansion model of culturing photoreceptors for the treatment of retinal degeneration diseases.

Bone Marrow Cells↗

PubMed2005

Intraocular pressure measured with a noncontact tonometer in an elderly Chinese population: the Shihpai Eye Study.

OBJECTIVE: To determine the distribution of intraocular pressure (IOP) as measured by a noncontact tonometer (NCT) and risk factors responsible for ocular hypertension in elderly Chinese people. DESIGN: Population-based study of randomly sampled Chinese people 65 years and older in Shihpai, Taipei, Taiwan. MAIN OUTCOME MEASURES: Participants completed an interview and underwent a physical examination and a standardized ophthalmic examination, including IOP measurement with the NCT. People with a history of glaucoma were excluded. Risk factors were assessed using multivariate regression analysis. RESULTS: Of 1361 study participants examined, 1292 (95.4%) had no history of glaucoma and were therefore included in the study. Their mean +/- SD IOP was 12.9 +/- 3.1 mm Hg. The IOP decreased significantly (P<.001) with age, changing from 13.3 +/- 3.0 mm Hg in participants aged 65 to 69 years to 11.6 +/- 2.8 mm Hg in those 80 years and older. Women had significantly higher IOP than men (P<.001). In the multivariate regression analysis, decreasing age, female sex, increasing systolic blood pressure, a history of diabetes, and alcohol drinking were significantly associated with increasing IOP. CONCLUSIONS: The distribution of IOP in elderly Chinese people is similar to that found in other East Asian people, with a negative age-IOP relationship. The mean IOP values in this elderly Chinese population were lower than in white people but higher than in Japanese people in similarly aged groups. Establishing the epidemiologic characteristics of IOP with the NCT is important for the mass screening of ocular hypertension.

Aged↗

PubMed2005

Body mass index and age-related cataract: the Shihpai Eye Study.

OBJECTIVE: To investigate the association between body mass index (BMI) (calculated as weight in kilograms divided by the square of height in meters) and cataract in a metropolitan Asian elderly population. DESIGN: Population-based cross-sectional study. Age-related cataract was defined as any type of lens opacity (ie, nuclear, cortical, and posterior subcapsular opacity) with a Lens Opacities Classification System III grade of more than 2 in one or both eyes. Weight and height were measured by intensively trained interviewers. RESULTS: A total of 2045 subjects 65 years and older in Shihpai, Taipei, were invited to participate, and 1361 (66.6%) completed the survey. Of the subjects, 806 were diagnosed as having age-related cataracts. With a BMI of less than 21.3 as a reference point (odds ratio [OR], 1.00), a U-shaped relationship between BMI and nuclear opacity was demonstrated. A reverse U-shaped relationship was shown for cortical opacity. In the final multiple logistic regression models, BMI and BMI(2) were significantly related to nuclear opacity (BMI data: OR, 0.73 [95% confidence interval {CI}, 0.54-0.98]; and BMI(2) data: OR, 1.01 [95% CI, 1.00-1.01]) and cortical opacity (BMI data: OR, 1.52 [95% CI, 1.04-2.34]; and BMI(2) data: OR, 0.99 [95% CI, 0.98-0.99]). Neither BMI nor BMI(2) was related to posterior subcapsular opacity. CONCLUSION: Body mass index is an independent risk factor for nuclear and cortical opacities, but in reverse direction to each other.

Aged↗

PubMed2005

Multiple elements in the deposits of opacified Hydroview intraocular lens.

PURPOSE: To report the ultrastructural and elemental features of two opacified intraocular lenses (IOLs). DESIGN: Histopathologic case series. METHODS: Two opaque hydrophilic acrylic IOLs (Hydroview H60M, Bausch & Lomb Surgical Clearwater, Florida, USA) explanted from two Chinese patients in Taiwan. The explanted IOLs were evaluated by light microscopy, scanning electron microscopy, and energy-dispersive x-ray spectroscopy. RESULTS: Brownish granular and scattered crystal-like deposits were found in case 2, whereas only fine white granular deposits were found in case 1. Using EDX spectroscopy, the elements of deposits on IOL optics were calcium and phosphorus in case 1, but in case 2, fluorine, magnesium, and sodium were demonstrated in addition to calcium and phosphorus. CONCLUSIONS: Our study indicated a difference in morphology and elements of deposits on opaque IOL optics between these two cases. It was suggested that multiple elements may contribute to the formation of deposits.

Acrylic Resins↗

PubMed2005

Electrophysiological changes in lipaemia retinalis.

PURPOSE: To report the electrophysiologic findings in a patient with lipaemia retinalis. DESIGN: Observational case report. METHODS: An 11-year-old girl with diabetes had hyperlipidemia and presented for ophthalmologic consultation. Fundus examinations revealed milky discoloration of retinal vessels in both eyes. Laboratory testing disclosed hyperglycemia and markedly elevated level of triglycerides and cholesterol. Although the visual acuity was not affected, the electroretinograms showed decrease amplitudes of a- and b-wave in both cone and rod responses. RESULTS: After correction of blood sugar and lipids with insulin and diet control, the lipaemia retinalis resolved, and the impaired ERG response reversed within 1 week. CONCLUSIONS: Lipaemia retinalis usually resolves rapidly without visual impairment after correction of hyperlipidemia. The reversible deficits of electroretinogram response in lipaemia retinalis are reported for the first time. High level of triglycerides or cholesterol or both may impair retinal function. The mechanism of an impaired electroretinogram remained speculative.

Blood Glucose↗

PubMed2005

Laser-assisted subepithelial keratectomy for dry eye associated with soft contact lenses.

PURPOSE: To evaluate the efficacy and safety of laser-assisted subepithelial keratectomy (LASEK) in myopic patients with preoperative dry eye associated with extended soft contact lens use. SETTING: Department of Ophthalmology, Taipei Veterans General Hospital, Taipei, Taiwan. METHODS: This nonrandomized prospective interventional case series study comprised 9 patients (18 eyes) with dry eye and keratoconjunctivitis associated with long-term complicated soft contact lens use. Prior to LASEK surgery and for 1 year following surgery, measurements and comparisons were made of uncorrected visual acuity, best corrected visual acuity (BCVA), manifest refraction, symptoms, tear function, ocular surface abnormality, and corneal sensitivity. RESULTS: No significant differences (P > .05) in the mean results of the Schirmer test with anesthesia and tear breakup times before and after LASEK were evident. Corneal sensitivity recovered within 1 month after LASEK. No complications occurred during or after LASEK. Subepithelial haze and superficial punctate epithelial defects occurred in 1 eye, representing a loss of 1 Snellen line of BCVA. CONCLUSION: Laser-assisted subepithelial keratomileusis in dry eyes and keratoconjunctivitis associated with complicated soft contact lens wearing was safe and efficacious.

Adult↗

PubMed2005

Central corneal mosaic opacities in Schnyder's crystalline dystrophy.

PURPOSE: To report an unusual presentation of Schnyder's corneal crystalline dystrophy (SCCD), sharing the feature of central corneal mosaic opacities. DESIGN: Observational case report. METHODS: A 51-year-old man and his family members were examined. Investigations included slit-lamp biomicroscopy, radiography of knee joint, plasma lipid level, and genotyping of the SCCD candidate region in chromosome 1p34.1-1p36. RESULTS: A symmetric, central, disciform, full-thickness opacity was seen in both corneas of the patient. The opacities appeared in a mosaic pattern, instead of collections of crystals or a diffuse haze as typically detected in SCCD. Small clumps of crystalline deposits and arcus lipoides were also observed. Systemically, hyperlipidemia and bilateral genu valgus were identified. He had 2 daughters, and both of them had bilateral corneal crystalline deposits and genu valgus. No other family members had findings suggesting SCCD. The genetic study demonstrated that all of the affected individuals shared a common haplotype within the region of previously reported SCCD locus. However, 1 unaffected sibling of the proband also had the same haplotype. CONCLUSIONS: Central corneal mosaic opacities may be another variant of SCCD.

Adolescent↗

PubMed2005

Photodynamic therapy for subfoveal choroidal neovascularization secondary to age-related macular degeneration.

BACKGROUND: To evaluate the safety and efficacy of verteporfin photodynamic therapy (PDT) in patients with subfoveal choroidal neovascularization (CNV) secondary to age-related macular degeneration (AMD). METHODS: We retrospectively reviewed the chart records and fluorescein angiography of patients with subfoveal CNV who were treated with verteporfin PDT between September 2001 and March 2003 and who completed at least 1 year of follow-up. The primary efficacy outcomes were the proportions of patients whose Snellen visual acuities had more than 1 line increase, no change or more than 1 line decrease 1 year after study entry compared with their baseline examinations. The secondary efficacy outcome was the changes in the logarithm of the minimum angle of resolution visual acuities at 1-year follow-up. Complications were monitored and tabulated. RESULTS: Forty-eight eyes of 48 patients with subfoveal CNV secondary to AMD were enrolled in this study. The mean follow-up was 12.56 +/- 1.37 months. At their last visit, 10.4% of eyes had more than 1 line improvement in Snellen visual acuity, 72.9% of eyes had no change, and 16.7% experienced more than 1 line of visual acuity loss (7 eyes lost < 3 lines of Snellen visual acuity, 1 eye lost between 3 and 6 lines). None experienced more than 6 lines of visual loss. There was no statistically significant difference between baseline and final visual acuity for eyes with predominantly classic CNV, minimally classic CNV and occult without classic CNV (Wilcoxon Signed Rank test, p = 0.59 ). There was a positive correlation between baseline visual acuity and final visual outcome (Kruskal-Wallis test, p = 0.002). No severe systemic and ocular adverse events were encountered. CONCLUSION: Of our patients with subfoveal CNV secondary to AMD, 83.3% could maintain or improve their visual acuity 1 year after verteporfin PDT. The risk of deterioration in visual acuity due to subfoveal CNV could be reduced by verteporfin PDT. Baseline visual acuity is significantly correlated with the final proportion of visual outcome.

Aged↗

PubMed2005

Pulsatile ocular blood flow in patients with Graves' ophthalmopathy.

PURPOSE: Graves' ophthalmopathy (GO) is a cosmetically disfiguring and vision-threatening complication of Graves' disease (GD). We investigated the clinical application of pulsatile ocular blood flow (POBF) measurement for detection of clinically active GO. METHODS: In this prospective study, the OBF tonometer (OBF Labs, Wiltshire, UK) was used to measure POBF in 83 eyes of 83 patients with GD in two groups and 42 normal control subjects. Group A comprised 35 GD patients without ophthalmopathy, and group B composed 48 GD patients with ophthalmopathy. Results were compared with controls. RESULTS: Pulse amplitude, pulse volume, and POBF were significantly lower in group B than that in group A and controls (P<0.001). After adjusting for age, sex, systolic blood pressure, diastolic blood pressure, heart rate, intraocular pressure, and axial length, multivariate linear regression analysis showed that POBF was still significantly lower in eyes with GO (772.4 (SD 279.3) microl/min) than group A (1177.3 (SD 326.3) microl/min) and controls (1255.4 (SD 295.1) microl/min) (P<0.001). CONCLUSIONS: These data show that the pulsatile ocular blood flow differences between the groups are relevant to the presence of GO. POBF measurement is a clinically useful adjunct for assessing the haemodynamic change in GO patients.

Adult↗

PubMed2005

Ocular hypersensitivitiy to topical vancomycin in a case of chronic endophthalmitis.

PURPOSE: To report a case of ocular allergy to topical vancomycin eye drops. METHODS: Interventional case report. RESULTS: A 76-year-old man presented with progressive itching, soreness, and burning sensations, photophobia, and tearing in his left eye 3 days after completing 2 weeks of treatment with 5% vancomycin eye drops. He had been suffering for the previous 2 years from chronic recurrent endophthalmitis and secondary glaucoma associated with cataract surgery in his left eye. He denied any history of drug or food allergy. Examination by slit-lamp microscope showed left periorbital skin erosive rash, marked hyperemia of conjunctiva, central epithelial defect, corneal stromal edema, and Descemet membrane striae. Vancomycin skin tests were positive. The patient's symptoms resolved after discontinuing vancomycin eye drops and responded well to systemic corticosteroids, antihistamines, and topical corticosteroid treatments. Teicoplanin treated his endophthalmitis successfully. CONCLUSION: A case of hypersensitivity to topical vancamycin was reported. Patients who receive topical vancomycin should be informed of this possible adverse effect and instructed to contact their ophthalmologists if allergic reactions occur.

Administration, Topical↗

PubMed2005

Association between symptoms and signs of dry eye among an elderly Chinese population in Taiwan: the Shihpai Eye Study.

PURPOSE: To analyze the association between dry-eye symptoms and signs in an elderly Chinese population in Taipei, Taiwan. METHODS: The participants were those of the Shihpai Eye Study, a population-based survey of eye diseases in the elderly (> or =65 years) in Shihpai, Taipei, Taiwan. Of 2045 randomly selected noninstitutionalized residents, 1361 (66.6%) participated in the study. Dry-eye symptoms were evaluated with an interviewer-administered questionnaire. Dry-eye signs, including tear-film breakup time, Schirmer test result, score for fluorescein staining of the cornea, and meibomian gland dysfunction, were assessed. Correlations between symptoms and signs were analyzed. RESULTS: Of the participants, 33.7% (459/1361) were symptomatic, defined as reporting one or more symptoms often or all the time. A Schirmer result of < or =5 mm was the only sign associated with frequent symptoms (P = 0.028). Its sensitivity and specificity in detecting symptomatic subjects were 62.5% and 43.7%, respectively. The agreement between each sign was statistically significant, although weak, except that no correlation was found between the Schirmer result and meibomian gland anomalies. Of the symptomatic subjects, 85.4% (392/459) had either a low Schirmer result or a meibomian gland anomaly; 38.8% (178/459) of them were abnormal on both tests. CONCLUSIONS: The Schirmer test was shown to be incapable of detecting meibomian gland disease. However, a low Schirmer result was significantly associated with dry-eye symptoms in this elderly Chinese population. This result differs from that of previous reports of elderly white populations. Further studies are needed to determine whether this difference indicates racial diversity in the distribution and behavior of dry-eye diseases.

Aged↗

PubMed2004

Congenital esophageal stenosis owing to ectopic tracheobronchial remnants.

BACKGROUND/PURPOSE: Congenital esophageal stenosis owing to tracheobronchial remnants (TBR) is a rare condition. Inappropriate treatment often is carried out before the correct diagnosis is established. For a better understanding and management of this disease, patients with TBR treated at our hospital and collected from the literature are reviewed to evaluate the course of onset, associated anomalies, methods of diagnosis and treatment, and outcomes. METHODS: Three patients treated at our hospital and 59 patients identified from the literature were included in the study. Gender, age at onset of symptoms, age at definitive treatment, esophagographic findings, pathology, methods of treatment, and outcomes of the 62 patients were recorded and analyzed. RESULTS: Boys slightly predominated (33:28, 1 unknown gender). Symptoms of dysphagia and regurgitation developed at the mean age of 3.2 +/- 4.5 months. Definitive treatment was carried out at the mean age of 2.6 +/- 3.0 years with a time lag of 2.0 +/- 2.5 years from the onset of symptoms. Twenty-five patients had associated anomalies with esophageal atresia being the most prevalent. Esophagography showed segmental stenosis over the distal third of the esophagus in all patients except one. The esophagographic findings could be classified into 3 types: type Ia, 10 cases; Ib, 15 cases; type II, 14 cases; type III, 3 cases. A nonyielding esophageal stenosis without inflammation was the characteristic esophagoscopic finding. Esophagoscopic dilatation of the stenosis was attempted in 26 patients, but all failed, and 2 patients suffered esophageal perforation. Surgical resection was mandatory for all patients to restore their esophageal continuity. Postoperative complications included anastomotic stenosis, anastomotic leakage, hiatal hernia, and gastroesophageal reflux. CONCLUSIONS: TBR should be suspected in patients who present with a typical history of dysphagia after ingestion of solid food and have characteristic esophagographic and esophagoscopic findings. It has a strong tendency to occur with esophageal atresia. Esophagoscopic dilatation is ineffective and may render the patient at risk for esophageal perforation. Operation is the treatment of choice and carries little morbidity and mortality.

Anastomosis, Surgical↗

PubMed2004

Linear-long incisions with a small optical zone for the correction of astigmatism in older patients.

PURPOSE: To evaluate the efficacy of astigmatic keratotomy (AK) by paired linear (transverse)-long incisions within a small optical zone in older patients with 3.00 diopters (D) or more of astigmatism who are intolerant of contact lenses, spectacles, or both. DESIGN: Prospective, noncomparative case series. PARTICIPANTS: Twenty-one eyes (20 patients; age range, 58-87 years) treated at clinics of the Taipei Veterans General Hospital were included in this study. METHODS: Paired linear incisions (90 degrees in length) with a central optical zone (OZ) of 4.5 mm were made to correct high astigmatism in older patients. The incisions were 80% of the corneal thickness and parallel to the axis of the steepest cylinder. MAIN OUTCOME MEASURES: Refraction, keratometry, corneal topography, and visual acuity with and without correction were measured as the outcome indicators. RESULTS: The mean course of the stabilization of corneal curvature was 1.8 months. Significant improvement from a preoperative corneal astigmatism of 4.52+/-1.39 D to a postoperative value of 1.82+/-0.88 D (P<0.0001) was shown. Marked axis deviations of more than 30 degrees were observed in 5 cases and corneal perforation was observed in 1 case. When the corneal curvature stabilized, uncorrected visual acuity was improved by 2 lines or more in 15 eyes (71.4%). Spherical equivalents and best-corrected visual acuity did not change significantly. Postoperative glare was absent in all patients. CONCLUSIONS: We conclude that AK by linear-long incisions extending from a small OZ is effective and safe for correcting astigmatism.

Aged↗