Retinal thickness variation in the diabetic patient measured by the retinal thickness analyser

AIM—To evaluate the potential of the retinal thickness analyser (RTA) as an objective tool for assessment and follow up of diabetic macular oedema.
METHODS—A prototype of the RTA that operates on the principle of laser slit biomicroscopy was used. Retinal thickness was obtained in 41 eyes of 41 diabetic patients. The clinical diagnosis was cystoid macular oedema (CMO) in 10 eyes, clinically significant macular oedema (CSMO) without retinal cysts in 21 eyes, and "dry" macula following grid pattern laser treatment in 10 eyes. The control group consisted of 46 eyes of age matched healthy volunteers.
RESULTS—In normal eyes (46 eyes), the foveal thickness measured was 178 (SD 44) µm and the macular thickness around the fovea was 311 (51) µm. The eyes with CMO displayed the largest foveal thickening, 875 (287) µm (390% increase compared with normal values). The average thickness of the fovea in the non-cystoid CSMO group was 427 (175) µm (144% increase compared with normal fovea). The average thickness of the foveal centre in eyes judged as having "dry" macula after laser treatment was 315 (71) µm (77% increase compared with normal value and a 26% decrease in thickness compared with the CSMO eyes). Statistically significant differences were found in central thickness between these four groups (p = 0.0001). The average thickness at 500 µm surrounding the fovea was 566 (202) µm in the CSMO eyes compared with 311 (51) µm in normal eyes (80% increase). The "dry" macula group (after undergoing laser treatments) had an average thickness of 414 (94) µm (27% decrease compared with CSMO eyes and a 33% increase compared with eyes of healthy controls).
CONCLUSIONS—RTA is a system for quantifying macular thickness and imaging of macular pathology. The system can be a useful tool for diagnosis of macular diseases and for evaluation of the effect of treatment modalities.

Keywords: diabetic retinopathy; retinal thickness; macular oedema; retinal imaging     

Comparison of mean macular thickness using optical coherence tomography and visual acuity in diabetic retinopathy

BACKGROUND: The purpose of the present study was to quantitatively assess the mean macular thickness in diabetic patients using optical coherence tomography and its correlation with visual acuity. METHODS: A prospective case series study was undertaken of consecutive diabetic patients referred to a tertiary eye care centre for an eye check up from January 2003 to June 2003. One hundred and five eyes from 55 patients with varying degree of diabetes underwent optical coherence tomography examination. The study patients were divided into four groups: group I, non-proliferative diabetic retinopathy (NPDR); group II, NPDR with clinically significant macular oedema (CSME); group III, proliferative diabetic retinopathy (PDR); and group IV, PDR with CSME. RESULTS: The mean macular thickness of the entire group was 256.0 +/- 129.7 microm. A positive correlation (r = 0.424, P < 0.0001) was evident between mean macular thickness and visual acuity. CONCLUSION: Optical coherence tomography is a useful tool for objectively monitoring macular thickness in patients with diabetic retinopathy. Mean macular thickness correlates with visual acuity.     

The evaluation of macular thickness in patients with retinal detachment treated with conventional surgery--preliminary report

The aim of the study was to evaluate retinal thickness in macular area (before and after surgery), and its correlation with visual acuity in patients with retinal detachment treated conventional surgery. Twenty eyes of 20 patients, treated in our clinic and eyes of 20 healthy subjects without any ocular pathology were evaluated. Retinal thickness in macular area (obtained with retinal thickness analyzer RTA - TALIA Technology) and visual acuity achieved after surgery compared with ocular pathology before and after surgery were analyzed. The correlation between visual acuity changes after successful surgery and macular thickness was evaluated. Retinal thickening in macula in patients with detached retina (even if macula was attached), and immediately after successful surgery in comparison to control group was observed. In selected cases, withdrawal of subclinical macular edema correlated with improvement of visual acuity. RTA allows for quantitative evaluation of retinal thickness in macula and its correlation with visual rehabilitation in patients with retinal detachment treated conventional surgery. Therefore RTA can be a useful tool in monitoring and determining visual acuity improvement.     

Identification of diabetic macular oedema using retinal thickness measurements

BACKGROUND: Identification of clinically significant macular oedema (CSMO) involves human depth perception, which is subject to a degree of uncertainty. However, although the ability to obtain objective thickness measurements of the central macular region may be advantageous, the topography of the macular region suggests that average thickness measurements represent a simplification of the topographic profile of the region. This study explored the applicability of additional sub-analysis of central macular thickness measurements. METHODS: The study included 47 eyes of 47 normal subjects and 158 ocular examinations of 38 eyes from 22 diabetic subjects with and without CSMO. All eyes underwent central macular thickness measurements using retinal thickness analysis equipment. Eyes of diabetes subjects were classified as being without CSMO (n = 53), with focal CSMO (n = 50) and with diffuse CSMO (n = 55). The central macular region was subdivided into narrow concentric rings around the foveola, using a new invention, and the thicknesses of the individual concentric rings were calculated. The sensitivity and specificity of the CSMO diagnosis were established using the average thickness and the thicknesses of the concentric rings. RESULTS: The average thickness of the central macular region was found to be 165.1 microm in eyes of normal subjects and 192.3 microm in eyes without CSMO. It increased non-significantly to 198.2 microm in eyes with focal CSMO and significantly to 236.9 microm in eyes with diffuse CSMO. Sensitivity for focal CSMO was 48.0% with average thickness measurements and 83.6% with concentric rings. Corresponding values for detection of diffuse CSMO were 91.7% and 96.1%, respectively. Specificity was 77.4% with average thickness measurements and 79.7% with concentric rings. CONCLUSIONS: Thickness measurements of the central macular region can be used to distinguish between eyes with and without diffuse CSMO, but not between eyes with and without focal CSMO. Additional sub-analysis based on concentric rings around the foveola seems to be a useful clinical tool that increases diagnostic certainty in these eyes.     

Macular morphologic reconstruction and visual recovery in patients following macular hole surgery]

PURPOSE: To examine the characteristics of retinal reconstruction at the macula following macular hole surgery and to assess the impact of postoperative macular morphological changes on the visual outcome. METHODS: A prototype of the scanning retinal thickness analyzer (RTA) was used to obtain optical section images at the macula in 53 eyes of 52 patients who underwent macular hole surgery between April 1994 and July 1997. The mean age of participants was 64.7 years. At the time of RTA examination, macular hole was biomicroscopically closed in 49 eyes (91%) and unclosed in 5 eyes (9%). RESULTS: There were 5 types of cross-sectional images of postoperative maculae: normal foveal depression [19 eyes (36%)], crater-like fovea formation [12 eyes (22%)], flattened fovea [8 eyes (15%)], fovea with abraded retinal pigment epithelium [9 eyes (17%)], and persistant macular hole [5 eyes (9%)]. Central macular thickness measured by RTA was 165 +/- 39 (mean +/- standard dereation) microns in the normal foveal depression group, 210 +/- 67 microns in the crater-like fovea formation group, and 300 +/- 50 microns in the flatened fovea group. There were statistically significant differences (p < 0.01) between groups. Postoperative visual acuity was significantly different (p < 0.01) between these three groups, and central macular thickness was highly correlated with postoperative visual acuity (R = 0.70). CONCLUSION: Visual recovery following macular hole surgery is closely associated with the retinal reconstruction at the macula.     

Contrast sensitivity following focal laser photocoagulation in clinically significant macular oedema due to diabetic retinopathy

Purpose : To evaluate the influence of focal laser photocoagulation on contrast sensitivity in diabetic patients with clinically significant macular oedema (CSMO). Methods : A prospective non‐comparative interventional study was performed on a group of patients with CSMO at Dr Rajendra Prasad Centre for Ophthalmic Sciences, New Delhi, a tertiary eye care centre. Thirteen diabetic patients (14 eyes) with CSMO and no history of prior photocoagulation were recruited for this study. Direct focal photocoagulation of all leaking microaneurysms was performed using an argon green laser (514 nm). A contact lens was used as a slit lamp delivery system. Evaluation of the best corrected Snellen visual acuity, contrast sensitivity, slit lamp biomicroscopy, macular status on direct ophthalmoscopy and fluorescein angiography was carried out 1 month and 3 months after laser photocoagulation. Results : Following direct focal laser photocoagulation, focal CSMO resolved completely in all but one eye, 4–8 weeks later, as seen on slit lamp biomicroscopy and/or fluorescein angiography. Post‐treatment, visual acuity remained stationary in eight eyes, improved by one line in three eyes, by two lines in two eyes and by three lines in one eye. The mean ± SD pretreatment and post‐treatment decimal visual acuities were 0.49 ± 0.30 and 0.59 ± 0.28, respectively. The mean ± SD pre‐laser contrast sensitivity score was 121.3 ± 83.6, which increased significantly to a mean ± SD of 151.6 ± 80.5 following direct focal photocoagulation. Conclusion : Focal argon laser photocoagulation in CSMO in diabetics helps in improving the contrast sensitivity and stabilizes the visual acuity. The changes in contrast sensitivity and visual acuity are independent of each other.     

Macular thickness and systemic markers for diabetes in individuals with no or mild diabetic retinopathy

Background:  The relationship between diabetic risk factors and macular thickness in individuals without clinically detectable diabetic macular oedema has yet to be formally explored. The purpose of this study was to assess the correlation between macular thickness and diabetes control and duration.
Methods:  This was a prospective, cross-sectional study. All subjects underwent digital retinal imaging and Stratus OCT macular thickness scanning both eyes. Mean retinal thickness was determined for quadrants, rings, hemispheres, and for the central fovea (CFT), total fovea (TFT) and total macula (TMT).
Results:  We evaluated 92 non-diabetic controls, 92 diabetic subjects with no diabetic retinopathy (DR) and 24 subjects with mild DR at the Veteran's Hospital in Jamaica Plain, MA. In subjects with diabetes, there was a significant negative correlation between retinal thickness and diabetes duration in all macular quadrants, rings and hemispheres, and for CFT, TFT and TMT (CFT: P  = 0.0025, r  = −0.28; TFT: P  = 0.0062, r  = −0.25; TMT: P  = 0.0026, r  = −0.28). There was no significant relationship between retinal thickness and HbA1c level (average of last three readings), systolic or diastolic blood pressure, or triglyceride levels. Additionally, no significant differences in retinal thickness were found between controls, subjects with no DR and subjects with mild DR.
Conclusions:  In subjects with no or mild DR, macular and foveal thickness is significantly thinner with longer duration of disease. This may reflect neurodegenerative changes in the diabetic retina.     

视网膜厚度分析仪(RTA)在眼底病的初步应用

目的：用视网膜厚度分析仪（retinal thickness analyzer,RTA）定量化检查视网膜厚度，了解常见眼底病视网膜厚度的定量变化。方法：采用扫描式RTA观察正常眼及26例（46只眼）各种眼底病变者，产生视网膜的系列光学切面像。得到视网膜地形图和厚度值。结果：各种眼底病变在RTA上的形态改变为：糖尿病性黄斑水肿眼：视网膜厚度图显示有视网膜厚度增加和中心凹凹陷消失，中心性浆液性脉络膜视网膜病变；玻璃体视网膜界面抬高，浆液性浅脱离；黄斑裂孔；视网膜内界面的中断，可见孔周的视网膜下液和局部脱离，近视眼；视网膜的萎缩性改变；黄斑前膜；视网膜神经上皮前的膜状物伸进玻璃体内，上述图形都伴有量化数据分析。结论：RTA显示的视网膜地形图和厚度图可提高对眼底疾病特别是黄斑疾病的诊断能力。     

无明显视力下降的糖尿病患者黄斑区视网膜厚度的研究

目的:分析无明显视力下降的糖尿病患者与正常人黄斑区视网膜厚度的差异。方法:选取2018-04/2019-06在我院确诊为2型糖尿病且无明显视力下降(最佳矫正视力≥0.8)的患者40例79眼为观察组,同期选取健康志愿者64例119眼为对照组。采用3D OCT获得两组受检者黄斑区9个区域平均视网膜厚度和黄斑区中心凹视网膜厚度(CRT)、平均视网膜厚度(ART)及视网膜体积(TV),并分析两组受检者之间的差异。结果:观察组患者CRT、ART、TV(193.99±14.58μm、291.07±12.24μm、8.22±0.35mm 3)均明显高于对照组受检者(187.38±12.24μm、280.54±8.71μm、7.92±0.25mm 3),且观察组患者黄斑区9个区域平均视网膜厚度均明显高于对照组受检者,差异均有统计学意义(P<0.05)。结论:无明显视力下降的2型糖尿病患者早期黄斑区视网膜厚度和体积较正常人增加。     

Intravitreal triamcinolone for macular oedema: efficacy in relation to aetiology

PURPOSE: To evaluate the efficacy and safety of intravitreal triamcinolone in patients with macular oedema of varying aetiology. METHODS: Two milligrams of intravitreal triamcinolone acetonide was injected into 34 eyes with persistent macular oedema (17 eyes with macula oedema secondary to posterior uveitis, 13 eyes with diabetic retinopathy, and four with pseudophakic macular oedema). Best corrected visual acuity was determined and transfoveal optical coherence tomography performed after 1 week, 1 month, 3 months and 6 months. RESULTS: Treatment improved visual acuity and subjective visual quality, and reduced foveal thickness in eyes with posterior uveitis and eyes with macular oedema secondary to diabetic retinopathy. Eyes treated for pseudophakic cystoid macular oedema demonstrated no improvement. A total of 32% of patients experienced a significant post-injection increase in intraocular pressure. Endophthalmitis, rhegmatogenous retinal detachment and cataract were absent. CONCLUSION: Intravitreal triamcinolone appears to induce marked a improvement in macular oedema secondary to non-infectious uveitis and diabetic retinopathy.     

Quantifying alterations of macular thickness before and after panretinal photocoagulation in patients with severe diabetic retinopathy and good vision

PURPOSE: To investigate the alterations of macular thickness during and after panretinal photocoagulation (PRP) in patients with severe diabetic retinopathy and good vision, and to compare the outcomes of weekly and biweekly treatments. DESIGN: Prospective, comparative interventional case series. PARTICIPANTS: Thirty-six patients with severe nonproliferative diabetic retinopathy or non-high-risk proliferative diabetic retinopathy whose visual acuity was 20/20 or better before PRP. METHODS: Seventy-two eyes of 36 patients underwent scatter PRP in 4 sessions. The macular thickness was measured by optical coherence tomography. The photocoagulation sessions were performed weekly to one eye and biweekly to the other eye. Each eye was selected at random. MAIN OUTCOME MEASURES: Best-corrected visual acuity and macular thickness. RESULTS: Visual acuities were maintained in 89% of eyes with weekly treatments and 92% of eyes with biweekly treatments. Macular thickness was increased transiently in the central macula in both eyes, more in the weekly treated eyes, and then decreased to control levels in eyes treated biweekly but remained thickened in eyes treated weekly. CONCLUSION: For eyes with severe diabetic retinopathy and good vision, PRP with either weekly or biweekly treatment did not affect postoperative visual acuity. However, biweekly treatments allowed faster recovery of macular thickening after PRP than weekly treatments.     

Qualitative and quantitative OCT response of diffuse diabetic macular oedema to macular laser photocoagulation

Purpose

To assess the quantitative and morphological changes of the macula in response to macular grid laser for diabetic macular oedema (DMO) using optical coherence tomography (OCT).

Patients and Methods

Cirrus OCT macular cube scans of 30 eyes of 25 patients were retrospectively analysed before and 4 months after macular grid laser for diffuse DMO. The oedema was quantified and response evaluated in the nine early-treatment diabetic retinopathy study (ETDRS) zones of the macula. Post-laser OCT changes were compared with the baseline features, including morphology patterns, changes in both logarithmic transformed (logOCT) and standardised average macular thickness (AMT), total macular volume, number of parafoveal quadrants involved, and the presence of intact 3rd hyper-reflective band (HRB).

Results

The rate of change of retinal thickness in response to laser was maximum in the central (8.17%) and perifoveal inferior quadrants (0.04%). Diffuse retinal thickening on OCT responded best to treatment. The AMT of 300–350 μm had the worst response (+0.94%). Eyes with less than four quadrants of oedema showed good response. Disrupted HRB was associated with poor visual gain (−0.33 ETDRS letters).

Conclusion

The topographic location of oedema on the retinal map and the morphological patterns of the oedema on OCT are useful predictors of treatment response in diffuse DMO.     

Screening for cystoid macular oedema in children with uveitis using the retinal thickness analyser

Purpose: This study aimed to investigate the retinal thickness analyser (RTA) as a means to identify the presence of cystoid macular oedema (CMO) in children with uveitis, whether the course of CMO can be monitored using this method, and whether there is a trend towards a correlation between macular oedema and visual acuity (VA) in children. Methods: This prospective, cross‐sectional study with observer‐blinded analysis included 25 eyes. Standardized testing for best corrected distance VA (d‐VA), near (reading) VA (n‐VA) and slit‐lamp examination were conducted. Using the RTA, a 3 × 3‐mm scan of the macula was obtained, which was then used to discern CMO and calculate mean foveal thickness (MFT). Results: Macular scanning was possible in all children. Cystoid macular oedema was discerned in 10 eyes (40%) and ruled out in 15. In CMO eyes, d‐VA was 0.5 Snellen and n‐VA was 2 Jaeger; neither result differed significantly from those in eyes without CMO. Mean foveal thickness correlated with n‐VA (r = 0.511, p = 0.015), but not with d‐VA (r = 0.271, p = 0.191). After 3 months of tailored therapy, CMO was still detectable in six eyes. Changes in d‐VA in the CMO and non‐CMO groups were 3 ± 2.1 and 0.8 ± 1.8 Snellen, respectively; changes in n‐VA were 1 ± 1.4 and 0.1 ± 0.3 Jaeger, respectively. Changes in MFT were ? 244.8 ± 137.4 µm and ? 0.8 ± 18.1 µm, respectively. A statistically significant correlation was found between the changes in MFT and n‐VA (r = 0.629), but not with that in d‐VA (r = 0.292). Conclusions: We used the RTA to establish the presence or absence of CMO according to measurements of the macular region. Our findings show that CMO is a common complication in children with uveitis and can be present even in cases with good d‐VA. Mean foveal thickness as measured with the RTA correlates indirectly with n‐VA.     

Retinal thickness in healthy and diabetic subjects measured using optical coherence tomography mapping software

PURPOSE: To define the normal retinal thickness in healthy subjects using optical coherence tomography (OCT) mapping software and to assess the ability of OCT to detect early macular thickening in diabetic patients. METHODS: Six radial scans centered on the fixation point were done on 60 healthy eyes and 70 eyes of 35 diabetic patients without macular edema on biomicroscopy. Retinal thickness was measured automatically with OCT mapping software. Mean retinal thickness was compared in subgroups of healthy patients based on age, sex, and eye, and in the eyes of diabetic patients and healthy subjects. Thickening was diagnosed if mean retinal thickness of an area was greater than the mean thickness + 2SD in the corresponding area in healthy subjects; or if the difference between right and left eye exceeded the mean difference + 2 SD in a given area in healthy subjects. RESULTS: In healthy subjects, mean retinal thickness in the central macular area 1000 microm in diameter was 170+/-18 microm. There was no significant difference according to age, or left or right eye, but central macular thickness was significantly greater in men than women (p=0.0139). No difference was observed between the eyes of healthy subjects and diabetic patients without macular edema on biomicroscopy, but OCT detected early macular thickening in 12 diabetic eyes. CONCLUSIONS: In this study average retinal thickness and mean local variations in a normal population were defined using a commercially available mapping software. OCT seems a sensitive tool for detecting early retinal thickening.     

Retinal thickness change after focal laser treatment of diabetic macular oedema.

Laser photocoagulation has been used successfully for the treatment of clinically significant macular oedema to reduce the risk of loss of vision in diabetic patients. A quantitative method for measuring retinal thickness was applied to 20 patients with diabetic macular oedema before and 4 months after focal laser treatment to assess the reduction in retinal thickening and its relation to visual acuity. The degree of thickening at each location, defined by thickness index, was determined relative to the corresponding average value in normal subjects. Comparison of quantitative retinal thickness measurements before and after treatment demonstrated that treatment at thickness indices of approximately 1.6 (60% thickening) has nearly 50% probability for reversal of thickening to within the normal range (< or = 1.3), whereas at thickness indices greater than 2.8 (180% thickening) there is less than 2.5% probability that reversal will occur. The level of foveal thickening before treatment strongly correlated with the degree of thickening after treatment. Most of the eyes with an improvement in visual acuity had a foveal thickness within the normal range at 4 months' follow up. These findings suggest that quantitative retinal thickness measurement provides an objective assessment of the degree of macular oedema and can be useful for monitoring the efficacy of focal laser treatment in reducing the thickening and relating the latter to visual outcome.     

频域相干光断层扫描对糖尿病黄斑区厚度的应用研究

目的 利用频域相干光断层扫描(OCT)测量并分析糖尿病( DM)患者的黄斑区视网膜厚度.方法 DM组90例(90只眼),并分为分无糖尿病视网膜病变(NDR) 、非增殖期(NPDR) 及增殖期(PDR) 病变3组,每组各30例(30只眼),正常对照组30例(30只眼).分别行最佳矫正视力(BCVA)、裂隙灯、眼底彩照、荧...     

"Light" versus "classic" laser treatment for clinically significant diabetic macular oedema

AIM: To compare the effectiveness of "light" versus "classic" laser photocoagulation in diabetic patients with clinically significant macular oedema (CSMO). METHODS: A prospective randomised pilot clinical trial in which 29 eyes of 24 diabetic patients with mild to moderate non-proliferative diabetic retinopathy (NPDR) and CSMO were randomised to either "classic" or "light" Nd:YAG 532 nm (frequency doubled) green laser. "Light" laser treatment differed from conventional ("classic") photocoagulation in that the energy employed was the lowest capable to produce barely visible burns at the level of the retinal pigment epithelium. Primary outcome measure was the change in foveal retinal thickness as measured by optical coherence tomography (OCT); secondary outcomes were the reduction/elimination of macular oedema on contact lens biomicroscopy and fluorescein angiography, change in visual acuity, contrast sensitivity, and mean deviation in the central 10 degrees visual field. Examiners were masked to patients' treatment. RESULTS: 14 eyes were assigned to "classic" and 15 were assigned to "light" laser treatment. At 12 months, seven (50%) of 14 eyes treated with "classic" and six (43%) of 14 eyes treated with "light" laser had a decrease of foveal retinal thickness on OCT (p = 0.79). A comparison of reduction/elimination of oedema, visual improvement, visual loss, change in contrast sensitivity, and mean deviation in the central 10 degrees showed no statistical difference between the groups at 12 months (p>0.05 for all groups). CONCLUSIONS: This study suggests that "light" photocoagulation for CSMO may be as effective as "classic" laser treatment, thus supporting the rationale for a larger equivalence trial.     

Intravitreal triamcinolone as adjunctive treatment to laser panretinal photocoagulation for concomitant proliferative diabetic retinopathy and clinically significant macular oedema

Purpose: To evaluate the effect of intravitreal injections of triamcinolone acetonide (IVTA) combined with panretinal photocoagulation (PRP) on visual acuity (VA) and foveal thickness in patients with concomitant high‐risk proliferative diabetic retinopathy (PDR) and clinically significant macular oedema (CSMO). Methods: This retrospective interventional case series included seven eyes diagnosed with both high‐risk PDR and CSMO that underwent PRP and a single injection of 4 mg of IVTA. The main outcome measures were VA and foveal thickness, measured by optical coherence tomography (OCT) before treatment and throughout the follow‐up period. Results: Median follow‐up was 301 days (range 180–715 days). Foveal thickness data were available for four of seven eyes. Before the combined treatment, median LogMAR (logarithm of the minimum angle of resolution) VA and median foveal thickness were 1 (Snellen 20/200, range 20/40–20/800) and 559 µm (range 333–689 µm), respectively. After treatment, median vision improved to LogMAR 0.544 (Snellen 20/70, range 20/40–20/1000) (P = 0.13). Vision improved or remained stable in six of seven eyes. Median foveal thickness at final follow‐up was 436 µm (range 259–623 µm) (P = 0.15). Foveal thickness decreased or remained stable in all eyes. Conclusion: The addition of IVTA to PRP in the treatment of eyes with high‐risk PDR and CSMO may prevent PRP‐induced foveal thickening and loss of vision.     

糖尿病视网膜病变黄斑厚度及黄斑体积定量分析

目的:研究不同分期糖尿病视网膜病变患者黄斑厚度及黄斑体积的变化特点.方法:选取2016-01-01/2017-01-01于我院眼科门诊就诊的40例78眼糖尿病视网膜病变患者作为研究对象,根据糖尿病视网膜病变(diabetic retinopathy,DR)的国际临床分类法分为非增殖期糖尿病视网膜病变(non prolifertive dibetic retinopthy,NPDR)组20例40眼,增殖期糖尿病视网膜病变(prolifertive dibetic retinopthy,PDR)组20例38眼.全部研究对象进行光学相干断层扫描(optical coherence tomography OCT)检查,以直径1、3、6mm ETDRS对黄斑区进行分区,分析随着糖尿病视网膜病变严重程度的增加,黄斑中心凹及其周围分区各象限视网膜厚度及体积的变化特点.结果:NPDR组及PDR组黄斑中心小凹的厚度(foveola thickness,FT)分别为252.57±31.36、362.47±20.81μm,分区中内环上方、鼻侧最厚,下方次之,颞侧最薄;外环鼻侧最厚,上方次之,颞侧、下方最薄;NPDR组黄斑中心凹厚度及分区各象限视网膜厚度数值均小于PDR组,差异具有统计学意义(P<0.05).NPDR组及PDR组黄斑中心小凹处体积(V)分别为0.20±0.02、0.28±0.16mm3,分区中内环上方、鼻侧最大,下方次之,颞侧最小;外环鼻侧最大,上方次之,颞侧、下方最小;NPDR组黄斑中心凹体积及分区各象限视网膜体积数值均小于PDR组,差异具有统计学意义(P<0.05).结论:糖尿病视网膜病变患者黄斑中心凹及分区各象限视网膜厚度及体积变化与糖尿病视网膜病变的病程进展有关.利用OCT对不同分期糖尿病视网膜病变患者黄斑厚度及黄斑体积进行定量分析,了解随着糖尿病视网膜病变严重程度的增加,黄斑区及其周围分区视网膜形态学变化的特点,为更好地分析不同严重程度糖尿病视网膜病变黄斑部位结构改变提供临床研究依据.     

Quantitative assessment of retinal thickness in diabetic patients with and without clinically significant macular edema using optical coherence tomography

PURPOSE: To assess patients with diabetic macular edema quantitatively using optical coherence tomography (OCT). METHODS: OCT was performed in 14 eyes with diabetic retinopathy and ophthalmoscopic evidence of clinically significant macular edema (CSME) and in 19 diabetic eyes without CSME. Retinal thickness was computed from the tomograms at fovea and other 36 locations throughout the macula. RESULTS: The mean +/- standard deviation foveal thickness was 255.6 +/- 138.9 microm in eyes with CSME, and 174.6 +/- 38.2 microm in eyes without CSME (p = 0.051). Within 2000 microm of the center of the macula, eyes with CSME had significantly thicker retina in the inferior quadrant than those without CSME (p < 0.01). The foveal thickness was correlated with logMAR visual acuity (gamma = 0.68, p < 0.01). OCT identified sponge-like retinal swelling and/or cystoid macular edema in 11 (58%) eyes without CSME, and in 12 (86%) eyes with CSME. CONCLUSIONS: Criteria of CSME seem to be insufficient in really identifying macular edema. OCT may be more sensitive than a clinical examination in assessing diabetic macular edema and is a quantitative tool for documenting changes in macular thickening.