可疑青光眼患者清晨起床前后的体位变化和日常活动对眼压的影响

目的：观察可疑青光眼患者清晨起床前后的体位变化和日常活动对眼压的影响。 方法：使用Icare回弹式眼压计对51例100眼可疑青光眼患者进行清晨起床前后的卧、坐位和日常活动前后的眼压测量,对比分析卧、坐位眼压和日常活动前后的眼压测量结果。 结果：起床前卧、坐位测量的眼压均值分别为19.14±5.51和17.12±4.53mmHg,两者差别显著。清晨日常活动前后测量的眼压均值分别为17.12±4.53和14.44±3.90mmHg,两者有显著差别。 结论：起床前后的体位变化和日常活动可以导致显著的眼压变化。     

中央角膜厚度对24h眼压波动的影响

目的:探讨中央角膜厚度(central corneal thickness,CCT)对24h眼压波动的影响。方法:使用Goldmann眼压计测量39例78眼未治疗的青光眼患者和44例88眼年龄匹配的正常对照眼的24h眼压波动(5am,7am,10am,2pm,6pm,10pm),并用超声测厚仪测量CCT。结果:青光眼组和对照组的平均眼压分别为21.33±2.91和16.19±2.33mmHg(t=12.615,P=0.000);峰值分别为24.67±2.72和18.55±2.45mmHg(t=12.613,P=0.000);波动值分别为6.63±3.26和4.72±1.60mmHg(t=4.709,P=0.000);CCT分别为544.44±32.11和537.16±27.66μm(t=1.569,P=0.119)。CCT与青光眼组的眼压波动值无显著相关性(r=0.140,P=0.222);CCT与对照组的眼压波动值亦无显著相关性(r=0.050,P=0.642)。以CCT<545μm为薄角膜组,CCT≥545μm为厚角膜组进行对比分析,青光眼组和对照组的平均眼压、峰值、波动值的差异无显著性(P>0.05)。结论:CCT与24h眼压波动无显著相关性。     

Augeninnendruckmessungen im Tages- und Nachtverlauf bei Glaukompatienten und Normalprobanden mittels Goldmann- und Perkins-Applanationstonometrie

OBJECTIVE: Our aim was to evaluate intraocular pressure (IOP) levels in primary open angle glaucoma (POAG) patients and healthy controls during both the day and night while measuring in an upright as well as in a supine position. METHODS: In a prospective clinical trial, 30 glaucoma patients on topical treatment and 50 healthy controls received IOP measurements every 4 h for a 24 h period starting at 8 am. Additionally, blood pressure and heart rate were measured and perfusion pressures were calculated. At 12 am IOP was initially measured in a sitting position and then, after 20 min, in a supine position. At midnight this was carried out conversely. At 4 am IOP was measured in a supine position; all other measurements were performed in a sitting position. Measurements in the sitting position were performed by Goldmann and Perkins tonometry and in a supine position by Perkins tonometry. RESULTS: IOP was 1 mmHg lower in Perkins tonometry measurements compared to Goldmann tonometry. There was no difference between the two patient groups. In a supine position, IOP measured by Perkins tonometry was higher than in an upright position. At 12 am the difference was 1.8 mmHg+/-2.7 mmHg (p=0.001) in healthy subjects and 1.3+/-2.7 mmHg (p=0.013) in the POAG patients. At 12 pm the increase of IOP in the supine position was even more pronounced with 2.4+/-3.4 mmHg in healthy subjects and 5.6+/-3.2 mmHg in the POAG patients (p=0.001). The blood pressure and the perfusion pressure were lowest during night measurements. CONCLUSIONS: During diurnal IOP measurements in an upright position there were no statistically significant differences in IOP changes between groups. However, in a supine position IOP was significantly higher than in a sitting position and increased more in the glaucoma patients than in healthy controls. This observation might be due to a faulty regulation of the fluid shift in glaucoma patients and could cause progression of glaucomatous damage.     

Association of central corneal thickness and 24-hour intraocular pressure fluctuation

PURPOSE: To evaluate the association between office-hour central corneal thickness (CCT) and 24-hour intraocular pressure (IOP) fluctuation in patients with glaucoma. DESIGN: Observational case-control study. METHODS: Measurements of IOP were obtained every 2 hours during a 24-hour period from 52 untreated glaucoma patients and 29 age-matched normal control subjects housed in a sleep laboratory. Habitual IOP measurements were obtained using a pneumatonometer in the sitting positions during the diurnal/wake period (7 AM to 11 PM) and in the supine position during the nocturnal/sleep period (11 PM to 7 AM). CCT was measured in all subjects using ultrasound pachymetry once during office hours. The association between IOP fluctuation (peak IOP-trough IOP) during the 24-hour period and the office-hour CCT was assessed in both glaucoma patients and healthy age-matched controls using Spearman rank order correlation. RESULTS: There was no statistically significant correlation between IOP fluctuation and CCT in glaucomatous (P=0.405) and normal subjects (P=0.456). CONCLUSIONS: Twenty-four-hour IOP fluctuations were not correlated with single CCT measurements taken during office hours in glaucoma patients.     

Posture-induced changes in intraocular pressure: comparison of pseudoexfoliation glaucoma and primary open-angle glaucoma

Purpose

The objective of this study was to evaluate and compare the IOP values in the sitting and supine positions in primary open-angle glaucoma (POAG) and pseudoexfoliation glaucoma (PXG) patients. We also investigated possible relationships between the level of visual field damage and postural IOP change.

Methods

Twenty-nine patients with POAG and 32 patients with PXG were recruited to the study. An Icare PRO tonometer was used to measure IOP in the sitting and supine positions. Intraocular pressure in the sitting position was also measured with a Goldmann applanation tonometer (GAT). Humphrey field analyzer 750 data taken within the previous 3 months were obtained and analyzed.

Results

The mean difference between the GAT and the Icare PRO tonometer readings was 0.12 ± 0.8 mmHg, and the tonometers were in close agreement (r = 0.964; P < 0.0001). The mean Icare PRO IOP in the sitting position was 16.6 ± 3.3 mmHg in the POAG group and 14.9 ± 2.7 mmHg in the PXG group. The average rise was 1.7 ± 1.2 mmHg in the POAG group and 2.9 ± 1.9 mmHg in the PXG group. The difference in IOP between the sitting and supine positions was significant between the groups (P = 0.001). The ?IOP was negatively correlated with both the mean deviation and the visual field index (P < 0.0001 for both). The ?IOP and pattern standard deviation were positively correlated (P < 0.0001).

Conclusions

A higher increase in IOP was observed in PXG patients from the sitting to the supine position than in POAG patients. Postural variation in IOP was found to be associated with the severity of visual field damage.     

Corvis ST测量青光眼患者眼压及中央角膜厚度的准确性研究

目的：评估角膜生物力学分析仪（CST）测量青光眼患者眼压（IOP）及中央角膜厚度（CCT）的准确性,研究角膜生物力学参数对IOP的影响。方法：描述性研究。28 例（56 眼）明确诊断为青光眼的患者,由同一位高年资医师分别用CST及Goldmann压平眼压计（GAT）测量其IOP,采用CST和IOLMaster测量CCT。不同设备测量值比较采用配对t 检验,相关性分析采用非参数Spearman检验,一致性验证采用Bland-Altman检验。结果：CST与GAT测得IOP平均值分别为（19.5±12.0）mmHg（1 mmHg=0.133 kPa）、 （20.9±8.8）mmHg,差异无统计学意义;CST与IOLMaster测得CCT平均值分别为（544±40）μm、 （538±40）μm,差异无统计学意义。CST与GAT测得的IOP具有高度相关性（ρ=0.837,P ＜0.001）,CST与IOLMaster测得的CCT具有高度相关性（ρ=0.958,P ＜0.001）。GAT与CST测得的IOP差值均值为（1.3±5.4）mmHg,95%的一致性界限为（-9.3,12.0）mmHg,IOLMaster与CST测得的CCT差 值均值为（6±10）μm,95%的一致性界限为（-26,15）μm。结论：CST可获得精确的IOP与CCT,但CST测量的IOP稍低于GAT,在青光眼的诊治中不能完全替代GAT.     

角膜生物参数对青光眼患者眼压测量影响的研究

目的:探讨角膜生物参数对青光眼患者眼压测量的影响。方法:对80例121眼青光眼患者进行眼反应分析仪(ocular response analyzer,ORA)与Goldmann压平眼压计(Goldmann applanation tonometer,GAT)测量,并用先进的OrbscanⅡ眼前节分析系统测量中央角膜厚度(central corneal thickness,CCT)。结果:平均矫正眼压(IOPcc)值17.41±5.62mmHg;平均GAT值15.76±6.06mmHg;IOPcc与角膜滞后性(cornealhysteresis,CH)有相关性(P=0.000;r=-0.236);IOPcc与GAT显著相关(P=0.000;r=0.857);IOPcc与CCT无相关性。结论:对已经诊断的青光眼患者,平均IOPcc值高于平均GAT值;随着CH的降低,IOPcc值有升高的趋势;且IOPcc值不受CCT值的影响。     

Intraocular pressure and ocular pulse amplitude comparisons in different types of glaucoma using dynamic contour tonometry

PURPOSE: To compare the intraocular pressures (IOP) and ocular pulse amplitudes (OPA) in patients with different types of glaucoma, ocular hypertension (OHT), and normal controls (NC) using dynamic contour tonometry (DCT) and the goldmann applanation tonometry (GAT). METHODS: 906 eyes of 501 adult patients in the following five groups were included in this cross-sectional study: primary open angle glaucoma (POAG), normal tension glaucoma (NTG), Pseudoexfoliative Glaucoma (PXG), OHT, and NC. The following tests were performed simultaneously during a single visit: IOP using DCT and GAT; OPA using DCT and central corneal thickness (CCT) using ultrasound pachymetry. Mixed effects regression models were used to compare the DCT and GAT IOP measurements in the five groups; the effect of CCT on IOP and the relationship between OPA and IOP within each group. RESULTS: DCT consistently had higher IOP values than GAT in POAG, PXG, NTG, and controls (p < 0.001) but not in OHT (p = 0.84). DCT IOP did not change while GAT IOP showed a non-significant increase (p = 0.09) with increased corneal thickness in each group. OPA was found to be highest in OHT (3.61 mmHg) and lowest in the control group (2.86 mmHg) and significantly increased with IOP in all groups. CONCLUSIONS: DCT measures an IOP that is significantly higher than GAT IOP in glaucoma and control subjects but not in ocular hypertensives. Furthermore, the DCT may measure an IOP that is independent of the CCT, which may not be true for the GAT, which increases with the CCT. OPA was highest in OHT and may be affected by the IOP.     

角膜中央厚度与眼压读数

目的　探讨角膜中央厚度与眼压读数的关系。方法　对44例88眼屈光角膜手术前的患者,分别用压平眼压计和超声角膜测厚仪进行角膜中央厚度和眼压的测量,并对二者之间的关系进行统计分析。结果　Ⅰ组角膜中央厚度≥580μm,眼压为21.50～27.00mmHg(23.70mmHg±1.36mmHg)(1kPa=7.5mmHg),屈光度-2.00～-12.00D。Ⅱ组角膜中央厚度＜520μm,眼压为11.00～20.00mmHg(15.66mmHg±1.71mmHg),屈光度-1.25～-11.25D。Ⅰ组眼压高于Ⅱ组（P＜0.001）。结论　角膜厚度与眼压有明显的相关性,即角膜厚度增加眼压相应增高,当眼压读数高于正常时,应考虑到是角膜中央厚度的改变。     

Association between corneal hysteresis and central corneal thickness in glaucomatous and non‐glaucomatous eyes

Purpose: We aimed to determine corneal hysteresis values (CH) using the ocular response analyser (ORA) in non‐glaucomatous and glaucomatous eyes and their relationship with central corneal thickness (CCT). Methods: Corneal hysteresis, intraocular pressure (IOP) as measured by Goldmann applanation tonometry (GAT) and CCT were prospectively evaluated in 74 non‐glaucoma subjects with IOP < 21 mmHg and in 108 patients with treated primary open‐angle glaucoma (POAG). One eye in each subject was randomly selected for inclusion in the analysis. Results: Mean (± standard deviation [SD]) age was 59.2 ± 14.2 years in the non‐glaucoma group and 62.4 ± 9.8 years in the glaucoma group. Mean (± SD) GAT IOP was 15.7 ± 2.65 mmHg and 16.38 ± 2.73 mmHg in the non‐glaucoma and glaucoma groups, respectively. There was no statistically significant difference between the two groups in mean age (p = 0.396) or mean GAT IOP (p = 0.098). Mean (± SD) CH was 10.97 ± 1.59 mmHg in the non‐glaucoma and 8.95 ± 1.27 mmHg in the glaucoma groups, respectively. The difference in mean CH between the two groups was statistically significant (p < 0.0001). There was a strong positive correlation between CH and CCT in the non‐glaucoma group (r = 0.743) and a significantly (p = 0.001) weaker correlation (r = 0.426) in the glaucoma group. Conclusions: Corneal hysteresis was significantly lower in eyes with treated POAG than in non‐glaucomatous eyes. The corneal biomechanical response was strongly associated with CCT in non‐glaucoma subjects, but only moderately so in glaucoma patients. It can be assumed that diverse structural factors, in addition to thickness, determine the differences in the corneal biomechanical profile between non‐glaucomatous and glaucomatous eyes. Corneal hysteresis could be a useful tool in the diagnosis of glaucoma.     

不同眼压计类型和测量体位对青光眼眼压测量值的影响

目的比较压平眼压计和非接触眼压计在坐位和卧位时测得的眼压值,探讨眼压计类型和测量体位对青光眼眼压值的影响。方法对28例原发性开角型青光眼患者进行日问眼压曲线测量,测量时间分别为9：30、11：30、13：30、15：30。先在卧位下使用压平眼压计进行测量,然后在坐位下分别使用压平和非接触眼压计进行测量。采用方差分析比较不同时间点、不同测量方法所获得的眼压值。结果卧位压平、坐位压平及坐位非接触眼压计测得的眼压平均值分别为（24．47±10．35）、（21．95±9．73）、（18．37±8．18）mmHg。当非接触眼压在10～20mmHg时,坐位压平眼压较非接触眼压高1．9～3．9mmHg,卧位压平眼压较非接触眼压高3．0～6．4mmHg。3种测量方法测得的峰值眼压超过21mmHg的患者分别为20、14、10例,使用非接触眼压计可能漏诊50％眼压失控的患者。结论使用压平眼压计和非接触眼压计及不同测量体位会对眼压值产生不同的影响,使用非接触眼压计不能对眼压是否正常作出准确的判断,尤其是当眼压处于靶眼压附近时。     

Changes in intraocular pressure during prolonged (7-day) head-down tilt bedrest

PURPOSE: To determine the change in intraocular pressure (IOP) due to postural changes in young healthy volunteers. MATERIALS AND METHODS: Intraocular pressure was measured using a calibrated Pulsair noncontact tonometer in both eyes of 25 female volunteers in a sitting position and after 1, 3, and 10 minutes in a supine position. In the second part of the experiment (a 7-day -6 degrees head-down tilt [HDT]), IOP (at 8 am, 12 am and 6 pm) and corneal thickness (12 am) were monitored in 8 female volunteers before, during, and after the HDT period. Blood pressure, hematocrit, plasma volume and osmolality, and plasma catecholamines concentrations were also measured. RESULTS: Intraocular pressure was significantly higher in the supine position (16.1 +/- 3.6 mm Hg) than in the sitting position, with a mean pressure difference of 2.23 +/- 2.9 mm Hg after 1 minute, 0.9 +/- 3 mm Hg after 3 minutes, and 1.9 +/- 3.8 mm Hg after 10 minutes in a supine position (P < 0.001). During the period of HDT, IOP values decreased significantly on the fifth day (13.3 +/- 1.6 mm Hg, P = 0.03) and the seventh day (12.7 +/- 1.7 mm Hg, P = 0.02) when compared with IOP in the supine position (14.26 +/- 2 mm Hg). The corneal thickness increased significantly (P < 0.0001) at day 5 (549.25 +/- 48.7 microm) and day 7 (540.31 +/- 46.9 microm) compared with baseline (532.45 +/- 38.6 microm). Two days after the end of the HDT bedrest, the mean supine IOP significantly increased (14.1 +/- 1.8 mm Hg, P = 0.003) and corneal thickness was similar to that found at baseline. The mean decrease of IOP was positively correlated with that of the plasma volume (-10%, r = 0.61, P = 0.02) and negatively correlated with the mean rise of hematocrit (r = -0.5, P = 0.07), variables that are considered to be indirect measures of plasma dehydration. CONCLUSIONS: During a 7-day HDT bedrest experiment in healthy women, eyes seemed to compensate the moderate rise of IOP described between a sitting and a supine position, and exhibited a slight and progressive average decrease of 1.3 mm Hg. These physiological modifications could be related to an ocular dehydration or to systemic cardiovascular and hormonal variations during bedrest.     

日间与昼夜眼压曲线对异常眼压测量能力的比较

目的评价日间眼压曲线与昼夜眼压曲线对异常眼压测量的能力。方法对就诊于北京同仁眼科中心的21例原发性开角型青光眼（POAG）、11例可疑正常眼压性青光眼（SNTG）及24例可疑青光眼患者进行昼夜眼压曲线测量。间隔2 h后,先使用手持式压平眼压计测量24 h的卧位眼压得到昼夜卧位眼压曲线。在9：30、11：30、13：30、15：30,患者完成卧位眼压测量5 min后测量坐位眼压,5 min后再使用非接触眼压计测量眼压,分别得到日间卧位眼压曲线、日间坐位眼压曲线和日间非接触眼压曲线。定义眼压峰值〉21 mmHg时为峰值异常,眼压波动〉5 mmHg时为波动异常。分析日间眼压曲线与昼夜眼压曲线均值、峰值及波动值间是否存在差异。结果不同组别昼夜眼压均值为（20.24±2.45）～（22.32±6.02）mmHg,较日间眼压均值高-0.19～6.37 mmHg;昼夜眼压峰值在（24.17±3.42）～（26.43±6.23）mmHg,较日间眼压峰值高1.75～8.76 mmHg;昼夜眼压波动在（8.00±3.47）～（9.09±3.83）mmHg,较日间眼压波动高3.59～6.00 mmHg。眼压峰值多出现于夜间睡眠时,POAG、SNTG和可疑青光眼患者眼压峰值出现于23：30～5：30的概率分别为57.14%、72.73%和66.67%。日间眼压曲线无法确定昼夜眼压波动的异常,若以昼夜眼压曲线作为金标准,各组的敏感性为10.00%～36.84%。结论56例患者的峰值眼压多发生在夜间睡眠时,日间和昼夜眼压曲线测得的眼压均值、峰值、波动及发现异常眼压的能力存在差异,依靠日间眼压曲线很难对昼夜眼压的情况做出准确判断。     

24小时眼压监测中夜间眼压测量方法的探讨

目的比较24h眼压监测中夜间即刻坐位眼压值和坐起休息10min后测得的眼压值,探讨夜间眼压的不同测量方法对青光眼24h眼压昼夜波动的影响。方法对已确诊且未用药、未做过手术的48例正常眼压性青光眼及17例原发性开角型青光眼患者进行24h眼压监测,每2h1次,其中测量夜间0:00、2:00、4:00眼压时,逐个唤起患者后立即测,后嘱患者坐起休息10min再测,采用SPSS软件以配对t检验分析比较测量结果。结果夜间即刻坐位眼压值和坐起休息10min后测得的眼压值差异有统计学意义(P<0.001),正常眼压性青光眼与原发性开角型青光眼间眼压差值差异有统计学意义(P<0.05)。结论即刻坐位眼压值能更准确反映夜间眼压,对24h眼压测量及青光眼诊断及治疗更有价值,值得临床应用。     

近视患者中央角膜厚度的相关因素研究

目的:探讨影响近视患者中央角膜厚度(central corneal thickness,CCT)的因素。方法:本文所研究的近视及近视散光患者共307例614眼,用全自动电脑验光仪、角膜厚度测量仪、非接触式眼压计、A超、Orb-scan分别测量屈光状态、CCT,眼压(intraocular pressure,IOP)、眼轴(axial length,AL)、前房深度(anterior chamber depth,ACD)以及角膜曲率(corneal curvature,CC)。用Pearson相关分析及一元线性回归方法统计评估CCT与眼部参数的关系。结果:CCT平均值为542.30±33.52μm。Pearson相关分析显示CCT与IOP呈显著正相关(r=0.303,P=0.000),与平均CC呈显著负相关(r=-0.129,P=0.001),而与年龄(r=-0.050,P=0.213)、屈光度(r=0.024,P=0.561)、AL(r=0.061,P=0.131)、ACD(r=-0.031,P=0.445)等因素无关。结论:近视患者CCT与IOP及平均CC有相关性,CCT每增加100μm,IOP升高2.4mmHg。     

正常眼压性青光眼与原发性开角型青光眼24小时眼压曲线的比较

目的 通过24 h眼压的测量来深入分析比较正常眼压性青光眼(NTG)与原发性开角型青光眼(POAG)的眼压曲线特征.方法 前瞻性病例对照研究.收集2006年4月至2009年4月在上海市闸北区北站医院和复旦大学附属眼耳鼻喉科医院门诊就诊的NTG患者131例及POAG患者102例,测量24 h眼压,用非接触性眼压计从8 am起每隔2 h测一次眼压,0 am至6 am之间测得的为唤醒后即刻坐位眼压.主要观察指标为眼压波动曲线、平均眼压、峰值时间及眼压、谷值时间及眼压和眼压波动值.采用独立样本t检验和卡方检验比较各指标在两组之间的差异.结果 NTG组双眼平均眼压为(14.2±2.1)mmHg,低于POAG组[(19.9±3.5)mmHg];NTG组双眼峰值眼压为(17.0±2.4)mmHg,低于POAG组[(24.7±4.3)mmHg];NTG组双眼谷值眼压为(11.8±2.2)mmHg,低于POAG组[(16.5±3.1)mmHg];NTG组双眼眼压波动值为(5.2±1.8)mmHg低于POAG组(8.2±3.1)mmHg];两组的平均眼压、峰值、谷值及眼压波动值的差异均有统计学意义(t=-14.52、-16.44、-13.16、-8.90,P均＜0.01).NTG组63.3%患者、POAG组73.5%患者的峰值眼压位于门诊工作时间以外;尤其是NTG组有51.5%患者、POAG组有64.7%患者的峰值位于0 am至6 am时间段,两组差异有统计学意义(X2=8.150,P=0.017).结论 NTG及POAG患者24 h眼压曲线的变化规律具有相似性,是诊断和个体化治疗方案制订的依据,并可用作治疗随访中评价疗效和调整方案的重要参考指标.     

Comparison of the rebound tonometer with the Goldmann applanation tonometer in glaucoma patients

PURPOSE: To determine the agreement between the measurement of intraocular pressure (IOP) by the rebound tonometer (RBT) and by the Goldmann applanation tonometer (GAT) and to find out the effect of central corneal thickness (CCT) values on IOP measurements in glaucoma patients. METHODS: IOP was measured with the RBT and GAT, respectively, in 61 eyes of 61 glaucoma patients. CCT was measured using an ultrasonic pachymeter after all IOP determinations had been made. The mean IOP measurement by the RBT was compared with the measurement by the GAT, by Student's t-test. Bland-Altman analysis was performed to assess the clinical agreement between the two methods. The effect of CCT on measured IOP was explored by linear regression analysis. RESULTS: The mean patient age was 56.7+/-21.1 years (range: 30-80 years). There were 32 (52.46%) women and 29 (47.54%) men in the study group. The mean IOP readings were 18.70+/-4.76 mmHg using the RBT, and 18.27+/-3.49 mmHg using the GAT. The difference was not statistically significant (mean difference 0.43+/-2.55, P=0.2). A frequency distribution of the differences demonstrated that in more than 80% of cases the IOP readings differed by <2.3 mmHg between the RBT and GAT. There was a strong correlation between the RBT and GAT readings (r=0.852, P<0.0001). The IOP measurements with the two methods were correlated with CCT (r=0.40, P=0.02 for the RBT and r=0.48, P<0.0001 for the GAT). The IOP increased 1.1 mmHg and 8 mmHg for every 100-microm increase in CCT for the GAT and RBT, respectively. CONCLUSION: The RBT slightly overestimated the IOP value by 0.43 mmHg on average when compared with the GAT. Nevertheless, the RBT readings appeared to be more affected by the various thicknesses of different corneas when compared with those obtained using the GAT.     

Circadian variations in central corneal thickness and intraocular pressure in patients with glaucoma

AIM: To analyse 24 hour variations in intraocular pressure (IOP) and central corneal thickness (CCT) in a group of glaucomatous patients. METHODS: 30 patients with primary open angle glaucoma were hospitalised and underwent circadian evaluations (at 8 pm, midnight, 4 am, 8 am, noon, and 4 pm) of supine and sitting IOP, respectively, measured using a Perkins and a Goldmann tonometer, and CCT measured using an ultrasonic pachymeter (the mean value of three measurements within 5 mum). All patients were treated with timolol 0.5% twice daily and latanoprost 0.005% once daily. RESULTS: Mean supine IOP was 15.3 (SD 3.7) mm Hg (range 10-25), with circadian fluctuations of 7.3 (3.3) mm Hg. Mean sitting IOP was 15.1 (3.9) mm Hg (range 8-26), with circadian fluctuations of 5.4 (3.1) mm Hg. Mean CCT was 534 (39) microm (range 443-637 microm) with circadian fluctuations of 16.5 (6.2) microm (range 6-31 microm). Both the within patient and within time point fluctuations in CCT were statistically significant (p<0.0001, ANOVA). CONCLUSIONS: The authors found considerable fluctuations in 24 hour IOP. The circadian fluctuations in CCT were small and, although statistically significant, did not seem to interfere with the circadian IOP assessment.     

Effects of trabeculectomy on posture-induced intraocular pressure changes over time

Introduction

To determine whether trabeculectomy affects postural-induced changes in intraocular pressure (IOP), and whether it is maintained.

Methods

Thirty-six eyes of 36 patients with open-angle glaucoma who were scheduled for their initial trabeculectomy with adjunctive mitomycin C were prospectively examined. The IOP was measured in the sitting and the lateral decubitus position with an ICare rebound tonometer before, and 1, 3, and 12?months after trabeculectomy.

Results

Twenty-nine eyes of 29 patients completed this study. The mean baseline IOP measured with the ICare tonometer was 17.4?±?4.9?mmHg in the sitting position and 21.3?±?5.6?mmHg in the lateral decubitus position (p?p?p?=?0.004 respectively). This decrease in the degree of posture-dependent IOP change was maintained at +1.7?±?2.2?mmHg at 1 year postoperatively (p?Conclusions Our results indicate that trabeculectomy not only reduces the IOP but also reduces the degree of posture-induced changes in the IOP. Our findings also speculate that measuring the postural IOP changes after trabeculectomy might provide a clue on the functioning of a filtering bleb.     

Assessment of the diurnal variation in central corneal thickness and intraocular pressure for patients with suspected glaucoma

OBJECTIVE: To assess whether a single daily measurement using ultrasonic pachymetry gives a representative assessment of mean central corneal thickness (CCT) in patients with suspected glaucoma and whether diurnal changes in CCT are related to diurnal variations in intraocular pressure (IOP). DESIGN: Cross-sectional study. METHOD: Central CCT and IOP were measured by a single observer in 56 eyes of 28 patients with suspected glaucoma using an ultrasonic pachymeter and a Goldmann tonometer. Four measurements were made over a 24-hour period: at 8:00 AM, 12:00 PM, 4:00 PM, and 8:00 PM. MAIN OUTCOME MEASURES: Intraocular pressure and pachymetry. RESULTS: Mean IOP was 19.80 mmHg at 8:00 AM (95% confidence interval [CI], 18.95-20.66 mmHg), 20.38 mmHg at 12:00 PM (95% CI, 19.49-21.26 mmHg), 19.91 mmHg at 4:00 PM (95% CI, 19.99-21.83 mmHg), and 19.23 mmHg at 8:00 PM (95% CI, 18.35-20.11 mmHg). Mean CCT was 569.4 microm (95% CI, 560.2-578.7 microm), 567.6 microm (95% CI, 558.4-576.7 microm), 569.1 microm (95% CI, 559.5-578.6 microm), and 567.2 microm (95% CI, 557.9-576.4 microm) at the four respective time points. There was no significant correlation between IOP and CCT in any patient (Pearson rank correlation coefficient); nor was there any significant correlation between the mean diurnal variations of IOP and CCT. CONCLUSIONS: In this group of patients with suspected glaucoma, there was no significant variation in CCT. Therefore, a single measurement of CCT is sufficient when assessing patients with suspected glaucoma. There was no correlation between change of IOP and change of CCT.