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AIM: To evaluate the clinical outcomes of combined wavefront - guided and aspheric laser in situ keratomileusis ( LASIK ) to correct myopia and myopic astigmatism. METHODS: Prospective study. Forty-five patients ( 62 eyes ) with myopia and myopic astigmatism were randomly dividied into two groups:the wavefront-guided and aspheric LASIK group and the wavefront- guided LASIK group. Safety, efficacy, predictability, ocular higher order aberrations(HOAs), and contrast sensitivity under mesopic condition were compared at 6mo postoperatively. RESULTS: Both platforms had equal safety, efficacy and predictability. At 6mo after operation, total HOAs, spherical aberration and coma increased in both groups(P 0. 05 ), while contrast sensitivity in the wavefront-guided group recovered to preoperative levels at all spatial frequencies(P>0. 05). CONCLUSION: Wavefront-guided and aspheric LASIK induced less HOAs and associated with better mesopic contrast sensitivity compared with wavefront - guided LASIK.
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· AlM: To observe the characteristic of choroidal circulation in diabetics and investigate its changes as well as the relationship between it and the development and progression of diabetic retinopathy ( DR) . ·METHODS:All 45 diabetics were divided into 3 groups:no diabetic retinopathy ( NDR), nonproliferative diabetic retinopathy ( NPDR ) , proliferative diabetic retinopathy ( PDR);and 20 health people were selected to be control group.All subjects were examined by FFA and indocyaine green angiography ( lCGA ) ( Heidelberg retina tomography, Germany ) at the same time. The characteristics of angiograph results were comparatively observed and the feature of diabetic choroidapathy were analyzed. · RESULTS: ( 1 ) There were no significant differences between DR groups and control group in the central retinal artery ( CRA ) filling time.There were significant decreases of the choroidal artery filling time in DR groups, compared to the control group (P ·CONCLUSlON:lCGA may be a useful adjunct to FFA in the evaluation of choroidal vascular changes in DR.The research provides that the diabetic choroidal circulation was abnormal before the occurrence of DR, which fully proved the presence of diabetic choroidopathy.
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AIM: To compare the visual acuity and contrast sensitivity of eyes with different corneal spherical aberration implanted with the same aspherical IOL and evaluate the effect of different ocular spherical aberration on visual performance after phacoemulsification. METHODS:It was a prospective case series study. Forty-six eyes of thirty-nine age-related cataract patients in our department were included. The patients were divided into 3 groups according to the value of preoperative corneal spherical aberration. Eyes with corneal spherical aberration≤0. 2μm were assigned to group A, those with corneal spherical aberration >0. 2μm and ≤0. 3μm to group B, and those with corneal spherical aberration≥ 0. 3μm to group C. All patients underwent phacoemulcification and recieved AcrySof IQ aspheric IOL. Uncorrected visual acuity ( UCVA ) , best-corrected visual acuity( BCVA) , contrast sensitivity, and total ocular higher - order aberrations for a 6. 0mm pupil were recorded 3mo postoperatively. ANOVA were used to analyze the data. RESULTS: There were no significant differences in UCVA and BCVA between the 3 groups (P=0. 287, 0. 115). Contrast sensitivity was no statistically significant difference between the 3 groups at any spatial frequency under photopic、 mesopic, and mesopic with glare conditions (P>0. 05). With a 6. 0mm pupil diameter, root mean square values for total ocular higher - order aberrations were lower in groups A and B than that in group C (P=0. 000). The difference of total ocular spherical aberration was statistically significant between the 3 groups (P=0. 000). Coma and trefoil were similar between the groups (P=0. 788,0. 590), with no statistically significant differences.CONCLUSION:Implantation of the same aspherical IOL in eyes with different corneal spherical aberration results in similar visual acuity and contrast sensitivity. Small differences of ocular spherical aberration after phacoemulsification have no effect on visual performance.
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ObjectiveTo evaluate the diagnostic performance of CTCA in predicting myocardial perfusion defects through comparative analysis between MPI defects and severity of coronary stenosis on CTCA.MethodsFour hundred and seventy-eight patients who underwent CTCA and 99Tcm-MIBI MPI in the same period were analyzed retrospectively.According to the severity of coronary stenosis judged by visual evaluation of the vessel diameter,the patients were divided into five groups:no stenosis,mild stenosis,moderate stenosis,severe stenosis and total occlusion.MPI results were classified as negative or positive for perfusion defects,and the prevalence of perfusion defects in every group was calculated per-patient and per-vessel basis.The cut-off of stenotic severity for predicting myocardial perfusion defects was designated as 50％ or 75％,with MPI as standard reference.True positive,true negative,false positive and false negative statistics were thus determined separately on patient and vessel basis.The diagnostic performance for CTCA were calculated and compared.Pearson Chi-square and its partition tests or Fisher exact test were used to compare ordinal variables.ResultsFifty-eight patients showed myocardial perfusion defects.Either by patientbased or vessel-based analysis,the prevalence of myocardial perfusion defects showed an increasing trend with greater coronary artery stenosis in each group,and there were statistical differences among them (x2 =116.62 and 483.83,both P ＜ 0.05).On patient-based analysis,sensitivity ( SN),specificity ( SP),positive predictive value( PPV),negative predictive value(NPV) and accuracy (AC) for CTCA predicting myocardial perfusion defects were 62.1 ％ ( 36/58 ) and 34.5％ ( 20/58 ) (x2 =8.84,P ＜ 0.05 ),84.5％(355/420) and 97.1％ (408/420) (x2 =40.16,P ＜0.05),35.6％ (30/101) and 62.5％ (20/32) (x2 =7.19,P＜0.05),94.2％ (355/377) and 91.5％ (408/446) (x2 =2.18,P ＞0.05),81.8％ (391/478)and 89.5 ％ (428/478) (x2 =11.66,P ＜ 0.05 ) when the cutoff was set to 50％ and 75％,respectively.On vessel-based analysis,the SN,SP,PPV,NPV and AC for CTCA predicting myocardial perfusion defects were 58.8％ (40/68) and 30.9％ (21/68) (x2 =10.73,P ＜ 0.05),95.9％ (1768/1844) and 99.0％ (1826/1844) (x2 =36.72,P ＜ 0.05 ),34.5％ (40/116) and 53.8％ (21/39) (x2 =4.59,P ＜0.05 ),98.4％ (1768/1796) and 97.5％ ( 1826/1873 ) (x2 =4.14,P ＜ 0.05 ),94.6％ ( 1808/1912 ) and 96.6％ ( 1847/1912 ) (x2 =10.31,P ＜ 0.05 ),respectively.ConclusionsThe prevalence of myocardial perfusion defects correlates positively with the severity of coronary stenosis seen on CTCA.CTCA may predict perfusion defects with high SP and NPV.However,the PPV of CTCA in predicting myocardial perfusion defects is poor when the stenosis cut-off is set at 50％.It is significantly improved when the cutoff value is set at 75 ％.
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<p><b>OBJECTIVE</b>To investigate the diagnostic value of myocardial perfusion imaging (MPI) and multislice spiral computed tomography (MSCT) for coronary artery disease (CAD).</p><p><b>METHODS</b>Coronary angiography (CAG), MPI and MSCT were performed in 43 patients (36 with suspected, 7 with known CAD). MPI examinations were evaluated semiquantitatively by agreement of two experienced observers. SDS (summed difference score) > 1 was defined as reversible ischemia, and each myocardial segment was allocated to the territory of one of the coronary arteries. The MSCT results were defined as positive when stenoses (> or = 50%) were found in one main vessel or its main branch vessel. CAG results served as "gold standard". The diagnostic values of MPI and MSCT for CAD were compared respectively on patient basis and on vessel basis.</p><p><b>RESULTS</b>On patient basis, the sensitivity, specificity and accuracy of MPI for diagnosing CAD were 79.17%, 84.21% and 81.40% which were similar as those of MSCT: 83.33%, 89.47% and 86.05% (all P > 0.05). On vessel basis, the sensitivity, specificity and accuracy of MPI were 53.19%, 89.02% and 75.97% which were also similar to those of MSCT: 70.21%, 95.12% and 86.05% (all P > 0.05).</p><p><b>CONCLUSION</b>The non-invasive MPI and MSCT provide satisfactory and similar diagnostic information on diagnosing CAD.</p>