scholarly journals Parafoveal OCT Angiography Features in Diabetic Patients without Clinical Diabetic Retinopathy: A Qualitative and Quantitative Analysis

2017 ◽  
Vol 2017 ◽  
pp. 1-14 ◽  
Author(s):  
Mathilde M. Goudot ◽  
Anne Sikorav ◽  
Oudy Semoun ◽  
Alexandra Miere ◽  
Camille Jung ◽  
...  
Keyword(s):  
Diabetic Retinopathy ◽  
Quantitative Analysis ◽  
Capillary Density ◽  
Oct Angiography ◽  
Foveal Avascular Zone ◽  
Diabetic Patients ◽  
Cross Sectional ◽  
The Mean ◽  
Fundus Photographs ◽  
And Gender

Purpose. To evaluate the capacity of OCT angiography (OCTA) for detecting infraclinical lesions in parafoveal capillaries in diabetic patients without diabetic retinopathy (DR). Methods. This prospective observational cross-sectional case-control study analyzed the superficial and deep capillary plexuses (SCP and DCP) on macular OCTA scans (3 × 3 mm) centered on the fovea. We compared 22 diabetic patients (34 eyes included) without DR diagnosis on color fundus photographs, with 22 age- and gender-matched nondiabetic controls (40 eyes included). Qualitative analysis concerned morphological ischemic capillary alterations. Quantitative analysis measured foveal avascular zone (FAZ) size, parafoveal capillary density, and enlargement coefficient of FAZ between SCP and DCP. Results. Neither the qualitative nor quantitative parameters were significantly different between both groups. No microaneurysms or venous tortuosity was observed in any of the analyzed images. On the SCP, the mean FAZ area was 0.322 ± 0.125 mm2 in diabetic patients and 0.285 ± 0.150 mm2 in controls, P=0.31. On the DCP, the mean FAZ area was 0.444 ± 0.153 mm2 in cases and 0.398 ± 0.138 mm2 in controls, P=0.20. Conclusion. OCTA did not detect infraclinical qualitative or quantitative differences in parafoveal capillaries of diabetic patients without DR in comparison with nondiabetic controls.

scholarly journals Association of macular perfusion status with microvascular parameters up to the far periphery in diabetic retinopathy using multimodal imaging

2020 ◽  
Vol 6 (1) ◽  
Author(s):  
Dorottya Hajdu ◽  
Aleksandra Sedova ◽  
Felix Datlinger ◽  
Julia Hafner ◽  
Irene Steiner ◽  
...  
Keyword(s):  
Diabetic Retinopathy ◽  
Disease Duration ◽  
Retinal Ischemia ◽  
Vessel Density ◽  
Statistical Testing ◽  
Foveal Avascular Zone ◽  
Diabetic Patients ◽  
Cross Sectional ◽  
The Mean ◽  
Peripheral Areas

Abstract Background The aim of our study was to investigate a possible association between macular perfusion status and retinal ischemia and leakage up to far peripheral retinal areas in eyes with early to advanced stages of diabetic retinopathy (DR). Methods In a retrospective, cross sectional analysis ultrawide field (UWF) color fundus photos (Optos, Optomap California) were graded for DR severity. Foveal avascular zone (FAZ) and vessel density from the superficial (SCP) and deep capillary plexus (DCP) were assessed on optical coherence tomography angiography (OCTA) scans (Topcon, DRI-OCT Triton). UWF angiography images were used to quantify leakage/ischemic index and number of microaneurysms (MA). Age, gender, disease duration, type of diabetes, HbA1C, hypertension, complications of diabetes and ocular history were recorded. Univariate mixed models and Spearman correlation analysis were used for statistical testing. Results 24 eyes of 17 laser-naive diabetic patients with different stages of DR were analyzed. The mean age was 59.56 ± 8.46 years and the mean disease duration 19.65 ± 12.25 years. No statistically significant associations between FAZ size, macular vessel density of SCP/DCP and peripheral retinal ischemia, leakage and MA number were demonstrated. Higher stages of DR were associated with ischemic index (estimate [95% CI]: 13.04 [1.5; 24.5], p = 0.033) and MA count (estimate [95% CI]: 43.7 [15.6; 71.8], p = 0.01), but no association with leakage index was observed. Only weak correlations between DR severity and anamnestic data were found. Conclusion Retinal ischemic index and the amount of MAs assessed on UWFA up to peripheral areas are indicators of DR severity but not related to microvascular perfusion status in the macular region. Significance and timely sequence of macular vessel density in DR progression may need to be re-evaluated in future studies.

scholarly journals Association between Diabetic Retinopathy and Chronic Periodontitis—A Cross-Sectional Study

2018 ◽  
Vol 6 (4) ◽  
pp. 104 ◽  
Author(s):  
Veena H. R. ◽  
Sribhargava Natesh ◽  
Sudhir Patil
Keyword(s):  
Diabetic Retinopathy ◽  
Serum Creatinine ◽  
Glycated Haemoglobin ◽  
Cross Sectional Study ◽  
Diabetic Patients ◽  
Age Group ◽  
Sectional Study ◽  
Cross Sectional ◽  
Chronic Inflammatory Condition ◽  
The Mean

Periodontal disease (PD), a chronic inflammatory condition characterized by destruction of the supporting tissues of the teeth, increases the risk of complications in diabetics. Diabetic retinopathy (DR) is a microvascular complication of prolonged hyperglycaemia. There appears to be a similarity in the pathogenesis of DR and PD. Hence, this study aimed to investigate the association, if any, between DR and PD, correlate the severity of DR with the severity of PD, and investigate the association between glycated haemoglobin (HbA1c), serum creatinine and periodontal variables. The periodontal status of 200 adult diabetic patients in the age group of 30–65 years with varying severity of DR was assessed. Evaluation of the severity of PD was assessed by recording clinical parameters. Haematological investigations including glycated haemoglobin (HbA1c) and serum creatinine were estimated before the initiation of treatment for DR. A statistically significant association between the mean duration of diabetes mellitus (DM) and the severity of DR and PD was found. The severity of PD was directly correlated with the severity of DR. There was a significant association between the levels of HbA1c and serum creatinine and severity of DR and PD. There could be a plausible relationship between DR and PD. Further prospective studies on a larger population with longer follow-ups are required to ascertain whether PD and its severity directly affect the progression and severity of DR.

scholarly journals Level of VEGF-A and interleukin 6 in lacrimal fluid of patients with diabetic retinopathy

2020 ◽  
Vol 14 (3) ◽  
pp. 664-673
Author(s):  
Christelle Domngang ◽  
Armelle Lowe Noutchie ◽  
Pascal Djamen Chuisseu ◽  
Freddy Nemg Simo ◽  
Borris Tietche Galani ◽  
...  
Keyword(s):  
Diabetic Retinopathy ◽  
Interleukin 6 ◽  
Microvascular Complications ◽  
Cross Sectional Study ◽  
Elisa Test ◽  
Diabetic Patients ◽  
Vascular Endothelial ◽  
Cross Sectional ◽  
The Mean ◽  
Endothelial Growth Factor

Diabetic retinopathy (DR) is an ocular manifestation characterized by microvascular complications. The aim of this study was to investigate the relationship between diabetic retinopathy (DR) and two lacrimal angiogenic cytokines, interleukin-6 (Il-6) and vascular endothelial growth factor-A (VEGF-A). A cross-sectional study was conducted at Yaoundé Central Hospital from February,1 to June, 15, 2019. Twenty-six diabetic patients with retinopathy and 55 diabetics without retinopathy were enrolled. Tears were collected with Schirmer strips. The concentrations of VEGF-A and Il-6 were determined by the ELISA test. Statistical analysis was performed using Epi Data version 7.1.5.2. and GraphPad 5.0. The mean VEGF-A concentration was 163.4 ± 45.1 and 149± 81.8 pg/ml in patients with and without DR respectively (p= 0.292) while tear Il-6 level was 118.5±103 and 119±79.43 pg/ml in patients with and without DR respectively (p= 0.497). The mean tear VEGF level was 165.2 ± 76.10 and 153.50 ± 57.94 pg/mL in patients with and without diabetic maculopathy (DM) respectively (p=0.343) while tear Il-6 level was significantly lower in DM (54.92±32.68) compared to patients without DM (159.10±89.78) (p=0.047). Tear Il-6 level was significantly low in patients with DM. There was no association between the 2 lacrimal biomarkers and diabetic retinopathy. Further analysis is needed for this type of screening in diabetic patients.Keywords: eye, retina, tear, diabetes, biomarker; cytokine.

scholarly journals The Diagnostic Accuracy of an Intelligent and Automated Fundus Disease Image Assessment System with Lesion Quantitative Function (SmartEye) in Diabetic Patients

2019 ◽  
Author(s):  
Yi XU ◽  
Yongyi WANG ◽  
Bin LIU ◽  
Lin TANG ◽  
Liangqing LV ◽  
...  
Keyword(s):  
Diabetic Retinopathy ◽  
Quantitative Analysis ◽  
Diagnostic Accuracy ◽  
Proliferative Diabetic Retinopathy ◽  
Screening Program ◽  
Assessment System ◽  
Diabetic Patients ◽  
Fundus Images ◽  
Cross Sectional ◽  
Community Healthcare

Abstract Background: With the diabetes mellitus (DM) prevalence increasing annually, the human grading of retinal images to evaluate DR has posed a substantial burden worldwide. SmartEye is a recently developed fundus image processing and analysis system with lesion quantification function for DR screening. It is sensitive to the lesion area and can automatically identify the lesion position and size. We reported the diabetic retinopathy (DR) grading results of SmartEye versus ophthalmologists in analyzing images captured with non-mydriatic fundus cameras in community healthcare centers, as well as DR lesion quantitative analysis results on different disease stages. Methods: This is a cross-sectional study. All the fundus images were collected from the Shanghai Diabetic Eye Study in Diabetics (SDES) program from Apr 2016 to Aug 2017. 19904 fundus images were acquired from 6013 diabetic patients. The grading results of ophthalmologists and SmartEye are compared. Lesion quantification of several images at different DR stages is also presented. Results: The sensitivity for diagnosing no DR, mild NPDR (non-proliferative diabetic retinopathy), moderate NPDR, severe NPDR, PDR (proliferative diabetic retinopathy) are 86.19%, 83.18%, 88.64%, 89.59%, and 85.02%. The specificity are 63.07%, 70.96%, 64.16%, 70.38%, and 74.79%, respectively. The AUC are PDR, 0.80 (0.79, 0.81); severe NPDR, 0.80 (0.79, 0.80); moderate NPDR, 0.77 (0.76, 0.77); and mild NPDR, 0.78 (0.77, 0.79). Lesion quantification results showed that the total hemorrhage area, maximum hemorrhage area, total exudation area, and maximum exudation area increase with DR severity. Conclusions: SmartEye has a high diagnostic accuracy in DR screening program using non-mydriatic fundus cameras. SmartEye quantitative analysis may be an innovative and promising method of DR diagnosis and grading. Keywords: Diabetic retinopathy, Screening, Digital imaging processing, Lesion quantification, Epidemiology.

scholarly journals The Diagnostic Accuracy of an Intelligent and Automated Fundus Disease Image Assessment System with Lesion Quantitative Function (SmartEye) in Diabetic Patients

2019 ◽  
Author(s):  
Yi XU ◽  
Yongyi WANG ◽  
Bin LIU ◽  
Lin TANG ◽  
Liangqing LV ◽  
...  
Keyword(s):  
Diabetic Retinopathy ◽  
Quantitative Analysis ◽  
Diagnostic Accuracy ◽  
Proliferative Diabetic Retinopathy ◽  
Screening Program ◽  
Assessment System ◽  
Diabetic Patients ◽  
Fundus Images ◽  
Cross Sectional ◽  
Community Healthcare

Abstract Background With the diabetes mellitus (DM) prevalence increasing annually, the human grading of retinal images to evaluate DR has posed a substantial burden worldwide. SmartEye is a recently developed fundus image processing and analysis system with lesion quantification function for DR screening. It is sensitive to the lesion area and can automatically identify the lesion position and size. We reported the diabetic retinopathy (DR) grading results of SmartEye versus ophthalmologists in analyzing images captured with non-mydriatic fundus cameras in community healthcare centers, as well as DR lesion quantitative analysis results on different disease stages. Methods This is a cross-sectional study. All the fundus images were collected from the Shanghai Diabetic Eye Study in Diabetics (SDES) program from Apr 2016 to Aug 2017. 19904 fundus images were acquired from 6013 diabetic patients. The grading results of ophthalmologists and SmartEye are compared. Lesion quantification of several images at different DR stages is also presented. Results The sensitivity for diagnosing no DR, mild NPDR (non-proliferative diabetic retinopathy), moderate NPDR, severe NPDR, PDR (proliferative diabetic retinopathy) are 86.19%, 83.18%, 88.64%, 89.59%, and 85.02%. The specificity are 63.07%, 70.96%, 64.16%, 70.38%, and 74.79%, respectively. The AUC are PDR, 0.80 (0.79, 0.81); severe NPDR, 0.80 (0.79, 0.80); moderate NPDR, 0.77 (0.76, 0.77); and mild NPDR, 0.78 (0.77, 0.79). Lesion quantification results showed that the total hemorrhage area, maximum hemorrhage area, total exudation area, and maximum exudation area increase with DR severity. Conclusions SmartEye has a high diagnostic accuracy in DR screening program using non-mydriatic fundus cameras. SmartEye quantitative analysis may be an innovative and promising method of DR diagnosis and grading.

scholarly journals Changes of the Foveal Avascular Zone and Macular Microvasculature within the Framework of OCT Angiography Examination in Young Patients with Type 1 Diabetes (Pilot Study)

2020 ◽  
Vol 76 (3) ◽  
pp. 111-117
Author(s):  
Lukáš Magera ◽  
Jan Krásný ◽  
Patrik Pluhovský ◽  
Lucie Holubová
Keyword(s):  
Young Patients ◽  
Capillary Density ◽  
University Hospital ◽  
Oct Angiography ◽  
Foveal Avascular Zone ◽  
Control Group ◽  
Diabetic Patients ◽  
Avascular Zone ◽  
The Difference

Aim: Learn about the development and changes in foveal avascular zone (FAZ) and vascularity of retina in the surrounding zone, depending on the duration in young diabetic patients type 1 (T1DM). Methods: As part of regular one-year examinations of young T1DM patients at the Eye Clinic of the University Hospital Královské Vinohrady in Prague (Czech Republic, EU) from January to December 2019, OCT angiography using the device Spectralis (Heidelberg Engineering) was included. Forty patients aged 18 to 30 years were examined, median 21 years. T1DM was diagnosed in childhood and lasted for more than 10 years. At the same time, a control group of forty individuals of similar age, without metabolic and other general disease was examined, normal visual acuity and physiological fundoscopic finding were obligatory. The FAZ size was evaluated in both groups (using built-in function "Draw Region"), also its shape, density decrease and change in character of vascularity of the retina was assessed. Results: In the control group, the FAZ area ranged from 0.06 to 0.4 mm², with an average of 0.253 ± 0.092 mm² and a median of 0.27 mm². It was not affected by a fundamental change in its round shape and the surrounding capillary netting was regular and reasonably dense. In T1DM patients, the FAZ area was in a wider range, from 0.05 to 0.64 mm², an average of 0.300 ± 0.132 mm², and a median of 0.31 mm². The difference in FAZ across-the-board evaluation was statistically significant (p = 0, 009). Diabetic preretinopathy (DpR) was defined by the irregularity of the capillary density up to the manifestation of non-perfusion, in 61% of cases the size of the FAZ was changed. In diabetic retinopathy (DR) there was always an irregularity of the FAZ shape with its enlargement, manifestation of non-perfusion, capillary dilatation and rare microaneurysms. Conclusion: Changes in FAZ size corresponded to the stage of T1DM on the fundoscopic finding of the eye depending on its duration. The initial increased amount of foveal capillaries, which resulted in decreased FAZ area, was followed by a gradual decrease in capillaries and increased FAZ area, consistent with the manifestations of DpR. It was accompanied by a change in capillary density in macula to eventual non-perfusion. On the contrary, the increase in the FAZ area and its irregularity accompanied by non-perfusion of the capillary net and microaneurysms corresponded to the development of DR already.

scholarly journals The Diagnostic Accuracy of an Intelligent and Automated Fundus Disease Image Assessment System with Lesion Quantitative Function (SmartEye) in Diabetic Patients

2019 ◽  
Author(s):  
Yi XU ◽  
Yongyi WANG ◽  
Bin LIU ◽  
Lin TANG ◽  
Liangqing LV ◽  
...  
Keyword(s):  
Diabetic Retinopathy ◽  
Quantitative Analysis ◽  
Diagnostic Accuracy ◽  
Proliferative Diabetic Retinopathy ◽  
Screening Program ◽  
Assessment System ◽  
Diabetic Patients ◽  
Fundus Images ◽  
Cross Sectional ◽  
Community Healthcare

Abstract Background With the diabetes mellitus (DM) prevalence increasing annually, the human grading of retinal images to evaluate DR has posed a substantial burden worldwide. SmartEye is a recently developed fundus image processing and analysis system with lesion quantification function for DR screening. It is sensitive to the lesion area and can automatically identify the lesion position and size. We reported the diabetic retinopathy (DR) grading results of SmartEye versus ophthalmologists in analyzing images captured with non-mydriatic fundus cameras in community healthcare centers, as well as DR lesion quantitative analysis results on different disease stages. Methods This is a cross-sectional study. All the fundus images were collected from the Shanghai Diabetic Eye Study in Diabetics (SDES) program from Apr 2016 to Aug 2017. 19904 fundus images were acquired from 6013 diabetic patients. The grading results of ophthalmologists and SmartEye are compared. Lesion quantification of several images at different DR stages is also presented. Results The sensitivity for diagnosing no DR, mild NPDR (non-proliferative diabetic retinopathy), moderate NPDR, severe NPDR, PDR (proliferative diabetic retinopathy) are 86.19%, 83.18%, 88.64%, 89.59%, and 85.02%. The specificity are 63.07%, 70.96%, 64.16%, 70.38%, and 74.79%, respectively. The AUC are PDR, 0.80 (0.79, 0.81); severe NPDR, 0.80 (0.79, 0.80); moderate NPDR, 0.77 (0.76, 0.77); and mild NPDR, 0.78 (0.77, 0.79). Lesion quantification results showed that the total hemorrhage area, maximum hemorrhage area, total exudation area, and maximum exudation area increase with DR severity. Conclusions SmartEye has a high diagnostic accuracy in DR screening program using non-mydriatic fundus cameras. SmartEye quantitative analysis may be an innovative and promising method of DR diagnosis and grading.

scholarly journals Study of Serum Magnesium levels in diabetic patients with and without retinopathy.

2020 ◽  
Vol 27 (12) ◽  
pp. 2656-2661
Author(s):  
Sadiq Hussain ◽  
Sara Reza ◽  
Hashim Raza ◽  
Saleha Zafar ◽  
Sami Ahmad ◽  
...  
Keyword(s):  
Diabetic Retinopathy ◽  
Serum Magnesium ◽  
Serum Levels ◽  
Control Group ◽  
Diabetic Patients ◽  
Considerable Decrease ◽  
Lower Serum ◽  
Cross Sectional ◽  
The Mean ◽  
Healthy Participants

Objectives: The aim of our study is to evaluate the possible association of serum magnesium in diabetic patients with and without retinopathy. Study Design: Cross-sectional observational. Setting: Bahawal Victoria Hospital, Bahawalpur. Period: September, 2018 to May, 2019. Material & Methods: A total of 258 subjects were enrolled in the study. They were divided in 3 groups, which comprised of 208 diabetic patients; 92 with retinopathy, 116 without retinopathy and the control group comprised of 50 healthy individuals. Both cases and controls were subjected to blood tests for the estimation of biochemical parameters. Results: A considerable decrease was observed in the serum magnesium level of diabetics in comparison with the healthy participants. The mean serum magnesium levels amongst the groups were 1.5 ± 0.2 mg/dl and 2.4 ± 0.3 mg/dl respectively (p<0.001). There was also a marked variation in serum levels of magnesium among diabetic retinopathy patients and diabetics without complications i.e.1.3±0.1 mg/dl and 1.69±0.1 mg/dl respectively (p<0.001). Conclusion: Patients suffering from diabetic retinopathy displayed significantly lower serum magnesium levels in contrast to the control group and diabetics without retinopathy.

scholarly journals Ischemia modified albumin (IMA) and albumin adjusted-IMA (AAIMA) as biomarkers for diabetic retinopathy

2016 ◽  
Vol 7 (2) ◽  
pp. 117-123 ◽  
Author(s):  
Varikasuvu Seshadri Reddy ◽  
Sumita Sethi ◽  
Poonam Agrawal ◽  
Navdeep Gupta ◽  
Renu Garg
Keyword(s):  
Diabetic Retinopathy ◽  
Hdl Cholesterol ◽  
Serum Levels ◽  
Cross Sectional Study ◽  
Diabetic Patients ◽  
Albumin Concentration ◽  
Cross Sectional ◽  
Ischemia Modified Albumin ◽  
Cobalt Binding ◽  
The Mean

Introduction: Oxidative stress has important role in the pathophysiology of diabetic retinopathy (DR). Ischemia modified albumin (IMA) has been recently considered as a marker of oxidative damage in diabetes. However, there is scarcity of published information about both IMA and albumin adjusted-IMA (AAIMA) in DR patients. Objectives: To evaluate the serum levels of IMA and AAIMA in patients with DR and in healthy controls. Material and methods: This was a cross sectional study. Serum was obtained to measure lipids, albumin and IMA from the the patients with DR and non-diabetic subjects. The IMA level was measured by a colorimetric albumin cobalt binding (ACB) assay and the values were presented as absorbance units (ABSU). The IMA levels were adjusted for albumin interference and the AAIMA by using a formula [Individual serum albumin/median albumin concentration of the population X IMA]. Results: This study was done on 18 DR and 20 non- diabetic patients. The mean Serum IMA values in DR group and controls were 0.50±0.17 and 0.32±0.17, respectively (P=0.002). The mean serum AAIMA values in DR group and controls were 0.48±0.20 and 0.32±0.17, respectively (P=0.01). The albumin and HDL- Cholesterol levels were significantly lower in DR patients compared to controls (p=0.004 and p=0.01, respectively). Conclusions: The level of IMA and AAIMA were higher in cases of DR compared to that of non-diabetic subjects. The levels of albumin and HDL-Cholesterol were lower in DR patients compared to controls. 

scholarly journals The Diagnostic Accuracy of an Intelligent and Automated Fundus Disease Image Assessment System with Lesion Quantitative Function (SmartEye) in Diabetic Patients

2019 ◽  
Author(s):  
Yi XU ◽  
Yongyi WANG ◽  
Bin LIU ◽  
Lin TANG ◽  
Liangqing LV ◽  
...  
Keyword(s):  
Diabetic Retinopathy ◽  
Quantitative Analysis ◽  
Diagnostic Accuracy ◽  
Proliferative Diabetic Retinopathy ◽  
Screening Program ◽  
Assessment System ◽  
Diabetic Patients ◽  
Fundus Images ◽  
Cross Sectional ◽  
Community Healthcare

Abstract Background With the diabetes mellitus (DM) prevalence increasing annually, the human grading of retinal images to evaluate DR has posed a substantial burden worldwide. SmartEye is a recently developed fundus image processing and analysis system with lesion quantification function for DR screening. It is sensitive to the lesion area and can automatically identify the lesion position and size. We reported the diabetic retinopathy (DR) grading results of SmartEye versus ophthalmologists in analyzing images captured with non-mydriatic fundus cameras in community healthcare centers, as well as DR lesion quantitative analysis results on different disease stages. Methods This is a cross-sectional study. All the fundus images were collected from the Shanghai Diabetic Eye Study in Diabetics (SDES) program from Apr 2016 to Aug 2017. 19904 fundus images were acquired from 6013 diabetic patients. The grading results of ophthalmologists and SmartEye are compared. Lesion quantification of several images at different DR stages is also presented. Results The sensitivity for diagnosing no DR, mild NPDR (non-proliferative diabetic retinopathy), moderate NPDR, severe NPDR, PDR (proliferative diabetic retinopathy) are 86.19%, 83.18%, 88.64%, 89.59%, and 85.02%. The specificity are 63.07%, 70.96%, 64.16%, 70.38%, and 74.79%, respectively. The AUC are PDR, 0.80 (0.79, 0.81); severe NPDR, 0.80 (0.79, 0.80); moderate NPDR, 0.77 (0.76, 0.77); and mild NPDR, 0.78 (0.77, 0.79). Lesion quantification results showed that the total hemorrhage area, maximum hemorrhage area, total exudation area, and maximum exudation area increase with DR severity. Conclusions SmartEye has a high diagnostic accuracy in DR screening program using non-mydriatic fundus cameras. SmartEye quantitative analysis may be an innovative and promising method of DR diagnosis and grading.

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