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91.
Detecting early glaucoma by assessment of retinal nerve fiber layer thickness and visual function 总被引:7,自引:0,他引:7
Bowd C Zangwill LM Berry CC Blumenthal EZ Vasile C Sanchez-Galeana C Bosworth CF Sample PA Weinreb RN 《Investigative ophthalmology & visual science》2001,42(9):1993-2003
PURPOSE: To compare the abilities of scanning laser polarimetry (SLP), optical coherence tomography (OCT), short-wavelength automated perimetry (SWAP), and frequency-doubling technology (FDT) perimetry to discriminate between healthy eyes and those with early glaucoma, classified based on standard automated perimetry (SAP) and optic disc appearance. To determine the agreement among instruments for classifying eyes as glaucomatous. METHODS: One eye of each of 94 subjects was included. Healthy eyes (n = 38) had both normal-appearing optic discs and normal SAP results. Glaucoma by SAP (n = 42) required a repeatable abnormal result (glaucoma hemifield test [GHT] or corrected pattern standard deviation [CPSD] outside normal limits). Glaucoma by disc appearance (n = 51) was based on masked stereoscopic photograph evaluation. Receiver operating characteristic (ROC) curve areas, sensitivities, and specificities were calculated for each instrument separately for each diagnosis. RESULTS: The largest area under the ROC curve was found for OCT inferior quadrant thickness (0.91 for diagnosis based on SAP, 0.89 for diagnosis based on disc appearance), followed by the FDT number of total deviation plot points of < or =5% (0.88 and 0.87, respectively), SLP linear discriminant function (0.79 and 0.81, respectively), and SWAP PSD (0.78 and 0.76, respectively). For diagnosis based on SAP, the ROC curve area was significantly larger for OCT than for SLP and SWAP. For diagnosis based on disc appearance, the ROC curve area was significantly larger for OCT than for SWAP. For both diagnostic criteria, at specificities of > or =90% and > or =70%, the most sensitive OCT parameter was more sensitive than the most sensitive SWAP and SLP parameters. For diagnosis based on SAP, the most sensitive FDT parameter was more sensitive than the most sensitive SLP parameter at specificities of > or =90% and > or =70% and was more sensitive than the most sensitive SWAP parameter at specificity of > or =70%. For diagnosis based on disc appearance at specificity of > or =90%, the most sensitive FDT parameter was more sensitive than the most sensitive SWAP and SLP parameters. At specificity > or = 90%, agreement among instruments for classifying eyes as glaucomatous was poor. CONCLUSIONS: In general, areas under the ROC curve were largest (although not always significantly so) for OCT parameters, followed by FDT, SLP, and SWAP, regardless of the definition of glaucoma used. The most sensitive OCT and FDT parameters tended to be more sensitive than the most sensitive SWAP and SLP parameters at the specificities investigated, regardless of diagnostic criteria. 相似文献
92.
Relationship between visual field testing and scanning laser polarimetry in patients with a large cup-to-disk ratio 总被引:1,自引:0,他引:1
Tannenbaum DP Zangwill LM Bowd C Sample PA Weinreb RN 《American journal of ophthalmology》2001,132(4):501-506
PURPOSE: To determine the relationship between quantitative nerve fiber layer measurements and visual field testing in patients with large cup-to-disk ratios. METHODS: Seventy-six patients with vertical cup-to-disk ratios by contour of at least 0.8 on stereoscopic photographs and 50 normal subjects were included. One eye was randomly selected for study. All patients underwent standard achromatic automated perimetry, short-wavelength automated perimetry, and retinal nerve fiber layer measurements with scanning laser polarimetry. Analysis of variance was used to evaluate differences between the subject groups. Significance of pairwise comparisons was determined using the Tukey-Kramer multiple comparison test. RESULTS: Statistically significant differences in nerve fiber layer measurements between patients with large cup-to-disk ratios and both abnormal standard achromatic automated perimetry and short-wavelength automated perimetry (n = 22) and patients with large cup-to-disk ratios and both normal standard achromatic automated perimetry and short-wavelength automated perimetry (n = 42) were found for superior nasal ratio, maximum modulation, ellipse modulation, and the linear discriminant function (Tukey-Kramer less than.05). There was no significant difference in patients with abnormal short-wavelength automated perimetry only (n = 9) as compared with patients with both normal standard achromatic automated perimetry and short-wavelength automated perimetry and patients with both abnormal standard achromatic automated perimetry and short-wavelength automated perimetry. Statistically significant differences between the normal subjects and patients with large cup-to-disk ratios and both abnormal standard achromatic automated perimetry and short-wavelength automated perimetry were found for all retinal nerve fiber layer parameters, with the exception of symmetry, superior ratio, and inferior ratio. CONCLUSION: Our results show considerable overlap in nerve fiber layer measurements in eyes with large cup-to-disk ratio and abnormal visual fields as compared with eyes with large cup-to-disk ratios and normal visual fields. This may limit the clinical usefulness of scanning laser polarimetry for detection of early glaucoma in patients with large cup-to-disk ratios. Longitudinal studies are needed to determine if patients with large cup-to-disk ratios with normal standard achromatic automated perimetry and abnormal short-wavelength automated perimetry subsequently develop standard achromatic automated perimetry defects and if scanning laser polarimetry can concurrently detect progression of nerve fiber layer damage. 相似文献
93.
Lucas DG Patterson T Hendrick JW Holder J Sample JA Joffs C Davis J Goldberg A Mukherjee R Smits GJ Spinale FG 《Journal of cardiovascular pharmacology》2001,38(4):618-624
The adenosine subtype 1 (A1) receptor, which may influence cardiac function and modulate renal function, may have particular relevance in congestive heart failure (CHF). However, the effects of A1 receptor inhibition in the setting of CHF are poorly defined. Systemic hemodynamics and indices of renal function were measured in pigs with pacing-induced CHF at 240 bpm for 3 weeks (n = 10) before and after A1 receptor blockade with 100 microg of BG9719 (1,3-dipropyl-8-[2-(5,6-epoxynorbornyl)]xanthene) or in CHF pigs after infusion of vehicle only (n = 10). Heart rate, mean aortic pressure, and left ventricular peak pressure increased following A1 blockade in the CHF group, consistent with an adenosine inhibitory effect. However, cardiac output and global measures of vascular resistance did not significantly change following A1 blockade. Urine output increased twofold and sodium clearance increased threefold following A1 blockade (p < 0.05). Creatinine clearance increased following A1 blockade (127 +/- 17 vs. 62 +/- 7 ml/min, p < 0.05). Selective A1 receptor blockade improved glomerular filtration rate and induced a natriuresis and diuresis in a model of CHF without adverse effects on cardiac function. These unique results suggest that renal A1 receptor activation may contribute to the reduced renal function associated with CHF. 相似文献
94.
Revision of Failed Gastric Bypass to Distal Roux-en-Y Gastric Bypass: A Review of 65 Cases 总被引:1,自引:1,他引:0
Fobi MA Lee H Igwe D Felahy B James E Stanczyk M Tambi J Eyong P 《Obesity surgery》2001,11(2):190-195
Background: No bariatric operation has been documented to effect adequate weight loss in all patients. Patients with inadequate
weight loss or significant weight regain with an anatomically intact short-limb gastric bypass, of which the Fobi pouch operation
(FPO) for obesity is a modification, are usually revised to a distal Roux-en-Y gastric bypass (DRYGBP) to enhance weight loss.
Method: A retrospective review of the charts of all patients who had a revision to a DRYGBP at our Center during an 8-year
period was carried out and the findings analyzed. Results: 65 patients who had the FPO had a revision to the DRYGBP.Most were
super obese patients who, even though they had lost significant weight, were still morbidly obese. Some were patients who
had not lost adequate weight or <40% excess weight, and a small number were patients who requested more weight loss even though
they had a BMI of < 35. 15 patients developed protein malnutrition requiring supplemental feeding. 6 required rerevision to
short-limb gastric bypass. Conclusion: Revision of short-limb gastric bypass to DRYGBP usually enhances weight loss but at
a cost of an increased incidence of protein malnutrition. 相似文献
95.
�������������Ũ�������ھ���Ӫ�����������������̽�� 总被引:2,自引:1,他引:2
目的探讨瘦素质量浓度与早期静脉营养及生长发育的关系。方法新疆医科大学第一附属医院新生儿科于2005-01—2006-02,将收治的86例早产适于胎龄儿用随机数字表法分为观察组(早期微量喂养同时辅助胃肠外营养组)45例和对照组(单纯早期微量喂养组)47例,分别测定脐血及第7天血清瘦素质量浓度,同时监测营养状况和生长发育指标,并作对比分析。结果(1)观察组与对照组脐血瘦素质量浓度分别为(4.6±3.7)ng/mL、(4.8±2.2)ng/mL,生后第7天两组瘦素质量浓度分别为(4.3±2.2)ng/mL、(3.1±1.7)ng/mL。对照组第7天血清瘦素质量浓度明显低于脐血(P<0.05),而观察组其差异无统计学意义(P>0.05)。(2)脐血瘦素质量浓度与出生体重、胎龄成正相关(r=0.56、r=0.67)。(3)观察组第7天热卡及蛋白质摄入量、血清瘦素质量浓度、皮褶厚度变化值与对照组相比,差异有统计学意义(P<0.05)。结论对早产儿应尽早喂养,同时需要胃肠外营养作为肠内营养的补充。瘦素可作为新生儿营养效果判定的实验室指标之一。 相似文献
96.
Infection and erosion of the saphenous vein graft with mediastinal hemorrhage is a rare but highly lethal complication of cardiac surgery. This is associated with a mortality rate of 50%. We present a patient who died during the postoperative period due to this complication. 相似文献
97.
The clinicopathological associations of 33 singleton infants who died with intraventricular haemorrhage (IVH) without hyaline membrane disease (HMD) ('IVH only') were compared with those of 39 infants who died with IVH+HMD over the same gestation range in order to determine what factors other than those related to HMD may contribute to the pathogenesis of IVH. The incidence of 'IVH only' was inversely related to gestational age in the Hammersmith birth population, whereas the incidence of IVH+HMD rose to a peak at 28-29 weeks' gestation. Infants with 'IVH only' lived longer on average than those with IVH+HMD despite a lower birthweight and shorter gestation. Infants who died in the first 12 hours from 'IVH only' had suffered severe birth asphyxia but in those who died later the main symptom was recurrent apnoea. Fewer infants with asphyxia but in those who died later the main symptom was.recurrent apnoea. Fewer infants with 'IVH only' were given alkali therapy or were connected to the ventilator as compared to those with IVH+HMD, but there were no differences in alkali therapy in those who lived for 12 hours or more. In the 'IVH only' group there was a high incidence of haemorrhage from other sites and of bacterial infections. It is suggested that, in the absence of HMD, extreme immaturity is the main factor determining the occurrence of IVH. Birth asphyxia, apnoeic attacks, haemorrhage, and infections may play subsidiary roles, possibly through development of metabolic acidosis. 相似文献
98.
99.
Autologous blood donors (ABDs) have been reported to have favorable attitudes toward returning as homologous blood donors (HBDs), but the frequency of return has not been well documented. ABDs eligible by history to be HBDs were followed at one blood center: 255 donating for elective surgery and 234 donating during pregnancy were followed for an average of 18 months and 20 months, respectively, from time of eligibility after surgery or postpartum. Male ABDs had a higher rate of return as HBDs, as 34 percent (21/62) returned to donate an average of 3 units, whereas 13 percent (56/427) of female ABDs returned as HBDs to donate an average of 2 units. Although a history of donation was associated with a higher rate of return (30%, 34/113), 11 percent (43/376) of ABDs with no history as HBDs returned to donate homologous units, despite having been recruited less frequently than prior HBDs. Overall, all male ABDs and female ABDs with an HBD history returned most frequently. The extra effort required for an autologous donor program may result in the recruitment of new donors into the HBD pool. 相似文献
100.
Structure-function relationships using confocal scanning laser ophthalmoscopy, optical coherence tomography, and scanning laser polarimetry 总被引:3,自引:0,他引:3
Bowd C Zangwill LM Medeiros FA Tavares IM Hoffmann EM Bourne RR Sample PA Weinreb RN 《Investigative ophthalmology & visual science》2006,47(7):2889-2895
PURPOSE: To assess the strength of the association between retinal nerve fiber layer (RNFL) thickness and optic disc topography measured with confocal retinal tomography (HRT II; Heidelberg Engineering, Dossenheim, Germany), optical coherence tomography (StratusOCT; Carl Zeiss Meditec, Inc., Dublin, CA), and scanning laser polarimetry (GDx with variable corneal compensator, VCC; Carl Zeiss Meditec, Inc.), and visual field (VF) sensitivity and to determine whether this association is better expressed as a linear or nonlinear function. METHODS: One hundred twenty-seven patients with glaucoma or suspected glaucoma and 127 healthy eyes from enrollees in the Diagnostic Innovations in Glaucoma Study (DIGS) were tested on HRT II, StratusOCT, GDx VCC, and standard automated perimetry (SAP, with the Swedish Interactive Thresholding Algorithm [SITA]) within 3 months of each other. Linear and logarithmic associations between RNFL thickness (HRT II, StratusOCT, and GDx VCC) and neuroretinal rim area (HRT II) and SAP sensitivity expressed in decibels were determined globally and for six RNFL/optic disc regions (inferonasal, inferotemporal, temporal, superotemporal, superonasal, and nasal) and six corresponding VF regions (superior, superonasal, nasal, inferonasal, inferior, and temporal). RESULTS: The associations (R2) between global and regional RNFL/optic disc measurements and VF sensitivity ranged from <0.01 (temporal RNFL, nasal VF, and nasal RNFL, temporal VF; linear and logarithmic associations) to 0.26 (inferotemporal RNFL, superonasal VF; logarithmic association) for HRT II; from 0.02 (temporal RNFL, nasal VF; linear association) to 0.38 (inferotemporal RNFL, superonasal VF; logarithmic association) for OCT; and from 0.03 (temporal RNFL, nasal VF; linear association) to 0.21 (inferotemporal RNFL, superonasal VF; logarithmic association) for GDx. Structure-function relationships generally were strongest between the inferotemporal RNFL-optic disc sector and the superonasal visual field and were significantly stronger for StratusOCT RNFL thickness than for other instruments in this region. Global associations (linear and logarithmic) were significantly stronger using OCT compared with HRT. In most cases, logarithmic fits were not significantly better than linear fits when visual sensitivity was expressed in log units (i.e., decibels). CONCLUSIONS: These results suggest that structure-function associations are strongest with StratusOCT measurements and are similar between HRT II and GDx VCC and these associations are generally no better expressed logarithmically than linearly when healthy, suspect, and glaucomatous eyes are considered. 相似文献