Indian Journal of Clinical and Experimental Ophthalmology

Print ISSN: 2395-1443

Online ISSN: 2395-1451

CODEN : IJCEKF

Indian Journal of Clinical and Experimental Ophthalmology (IJCEO) is open access, a peer-reviewed medical journal, published quarterly, online, and in print, by the  Innovative Education and Scientific Research Foundation (IESRF) since 2015. To fulfill our aim of rapid dissemination of knowledge, we publish articles ‘Ahead of Print’ on acceptance. In addition, the journal allows free more...


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Reddy and Reddy: A comparative study of central corneal thickness in diabetics and non-diabetics using ultrasonic pachymetry


Introduction

Diabetes is fast gaining the status of a potential epidemic in India with more than 62 million diabetic individuals currently diagnosed with the disease. According to Wild et al. the prevalence of Diabetes is predicted to double globally from 171 million in 2000 to 366 million in 2030 with a maximum increase in India i.e. 79.4 million.1, 2

The disease is characterized by hyperglycemia and development of micro-macro vascular disorders, leading to functional and morphological disorders in several organs. Ocular manifestations include anterior ischemic neuropathy, glaucoma, cataract, retinal vein and arterial occlusions and retinopathy/maculopathy. Development of many of the diabetic complications is related to duration of disease and degree of metabolic dysregulation.3, 4, 5

Several studies have indicated changes in human corneal endothelial cell morphology in patients with T2DM.6, 7, 8 Hypothetically, these phenomena could be caused by chronic metabolic changes at cellular level that primarily affect the single layer of coherent endothelial cells.9 These largely hexagonal cells have practically no proliferative activity. They are responsible for maintaining hydration of the stroma by actively removing water, thus playing a pivotal role in maintaining the transparency of cornea.

It is hypothesized that few ion transport systems exist in the corneal endothelial cells to maintain the hydration and transparency of the corneal stroma. These ion transport systems mainly are Na+ - K + - ATPase, carbonic anhydrase and bicarbonate ions systems. The stroma imbibes water and swells up when the corneal epithelial and endothelial cell barrier is damaged, ultimately resulting in increased hydration of the corneal stroma and thickness.10

CCT is a sensitive indicator of health of cornea and serves as an index for corneal hydration and metabolism. Thicker and thinner corneas may lead to either overestimation or underestimation of intraocular pressure, which is the most important causal and treatable risk factor for glaucoma. It is also an important indicator of patency of corneal endothelial pump and can be objectively measured by ultrasound pachymetry, the current standard for corneal thickness measurement. Factors influencing corneal pachymetry include time of the day, age, use of contact lens, corneal degeneration.11

Effect of diabetes on CCT has not yet been clearly established. Few studies state that CCT is unaffected by diabetes, while few state that it would significantly increase in diabetics when compared to non-diabetics. Moreover, studies on this subject in Indian population are quite very few. This necessitated further evaluation of the association between CCT and diabetes mellitus.

Materials and Methods

This is a cross-sectional study carried out during the period of April 2018–September 2020 at tertiary care centre in North Karnataka. The study includes 168 adult subjects divided into 3 groups:

  1. 46 patients with T2 DM for a duration ≤ 10 years

  2. 40 patients with T2 DM for a duration > 10 years

  3. 82 controls

Patients were explained about the study and patients’ willful consent was taken. Details including history, clinical examination, investigations were recorded. Clinical examination includes visual acuity (by Snellen’s chart), slit lamp examination, dry and cycloplegic (if required) retinoscopy with streak retinoscope and subjective correction. Pachymetry and IOP (by applanation tonometry) were recorded.

CCT was measured using a hand held ultrasonic pachymetry (PAC Scan plus, model: 300 AP+, Sonomed). Corneas of both the eyes were anesthetized with topical anaesthetic eye drops 0.5% Proparacaine and readings were taken after 90 seconds of instillation. Patient was seated and asked to fixate at a target in the front. Pachymetry probe is brought in light contact with the cornea centrally and perpendicularly and 5readings on each side are taken. CCT was taken as the average of those 5 readings. On the basis of a study, anticipated Mean±SD of CCT in Diabetics was 564±30 and CCT in non-diabetics was 538±35.9 With the mean difference of thickness and common standard deviation, the minimum sample size is 40 per group with 95% level of significance and 90% power.

Formula used is

Calculated sample size per group = 40

Total sample size taken in the study is = 168

Diabetes for duration < or equal to 10 years N1 = 46

Diabetes for duration >10 years N2 = 40

Total study population= 86

Non-diabetics N3 = 82

Total sample size= 168

N = 2[((Zα + Zβ) * S) / d]2

Statistical tools used for data analysis and results

Tables are evolved through Data Analysis Tool in Ms-Excel as an add on Tool

  1. Covariance

  2. Correlation

  3. Analysis of variance (anova)

Inclusion criteria

  1. Patients with T2DM >30 years of age

  2. Glycosylated Hb ≤ 7.2%

Exclusion criteria

  1. Patients who had already undergone intraocular or corneal surgery

  2. Patients previously diagnosed with any corneal pathology

  3. Patients who had worn rigid contact lens during the month prior to ophthalmic examination

  4. Patients who had worn soft contact lenses 7days before ophthalmic examination

  5. Raised IOP

  6. Hypertension

  7. Diabetics with neuropathy or nephropathy

Results

Table 1

Comparison of CCT between diabetics and non-diabetics

Summary

Groups

Sample size

Sum

Average

Variance

RE(NOND)

82

43121

525.8659

275.5743752

LE(NOND)

82

43184

526.6341

255.1484493

RE(D)

86

45929

534.0581

357.5377565

LE(D)

86

45955

534.3605

339.880301

[i] Anova: Single Factor

By looking at average CCT of two different groups, diabetic group has greater value of CCT average ANOVA.

Table 2

Comparison of mean CCT between diabetics and non-diabetics

Source of Variation

SS

df

MS

F

P-value

F crit

Between Groups, SSB

5346.556

k-1=3

1782.185

5.785575987

0.000726

2.631811

Within Groups, SSW

102269.1

N-k=332

308.0394

Total

107615.6

335

Calculated F value (5.78)>tabulated F value (2.63), it is inferred that there is significant difference (increase in CCT value in diabetic group compared to non-diabetic group) since p=0.000726 <0.05.of CCT values within groups:

k = No. of columns

Figure 1

Distribution of cases and contr

https://typeset-prod-media-server.s3.amazonaws.com/article_uploads/e724804d-7070-4aeb-9ea4-fbc5b35fce25/image/57ca6bf1-a197-46a7-94af-de5406a65bfb-uimage.png

Comparison between LE CCT & RE CCT of diabetic group ≤ 10yrs AND comparison between LE CCT & RE CCT of diabetic group diabetic group> 10 years.

Table 3

Comparison of mean CCT between right eye and left eye in diabetic’s ≤10 years

Summary

Groups

Count

Sum

Average

Variance

Standard Deviation

Max.Value

RE

46

24449

531.5

294.7889

17.16941726

587

LE

46

24466

531.8696

294.6937

17.16664556

584

ANOVA

Source of Variation

SS

df

MS

F

P-value

F crit

Between Groups

3.141304

1

3.141304

0.010658

0.918004731

3.946876

Within Groups

26526.72

90

294.7413

Total

26529.86

91

[i] Anova: Single Factor

Calculated F value (0.0106) < tabulated F value (3.946), it is inferred that there is no significant difference in CCT values of RE and LE of diabetic age group of ≤ 10 years.

Table 4

Comparison of mean CCT between right eye and left eye in diabetics >10 years

Summary

Groups

Count

Sum

Average

Variance

Standard Deviation

Max.Value

RE

40

21480

537

422.5128

20.55511665

598

LE

40

21489

537.225

384.9994

19.62140054

596

ANOVA

Source of Variation

SS

df

MS

F

P-value

F crit

Between Groups

1.0125

1

1.0125

0.002508

0.960189073

3.963472

Within Groups

31492.98

78

403.7561

Total

31493.99

79

[i] Anova: Single Factor

Calculated F value (0.0025) < tabulated F value (3.963), it is inferred that there is no significant difference in CCT values of RE and LE of diabetic age group of >10 years since p=0.960 >0.05.

Figure 2

CCT averages in diabetics ≤10 years duration and >10yrs duration

https://typeset-prod-media-server.s3.amazonaws.com/article_uploads/e724804d-7070-4aeb-9ea4-fbc5b35fce25/image/193b5884-3795-4b20-abb6-f54624d697d5-uimage.png

Table 5

Comparison of CCT between diabetic groups of ≤10 years duration and >10 years duration

Summary

Groups

Count

Sum

Average

Variance

RE (=<10 yrs)

46

24449

531.5

294.7889

LE (=<10 yrs)

46

24466

531.8696

294.6937

RE (>10 yrs)

40

21480

537

422.5128

LE (>10 yrs)

40

21489

537.225

384.9994

[i] Anova: Single Factor

Table 6

Comparison of mean CCT between diabetics >10 years duration and ≤ 10 years duration

Anova

Source of Variation

SS

df

MS

F

P-value

F crit

Between Groups

1264.773

3

421.5909

1.220745

0.30384

2.658399

Within Groups

58019.69

168

345.3553

Total

59284.47

171

Calculated F value (1.220) <tabulated F value (2.658), it is inferred that there is no significant difference of CCT averages of these two groups, however by comparing averages, diabetic >10yrs group has relatively higher averages of CCT, since p=0.303 >0.05.

Table 7

Comparison of mean CCT among diabetics with mild, moderate & severe NPDR

Summary

Groups

Count

Sum

Average

Variance

RE

86

45929

534.0581

357.537756

LE

86

45955

534.3605

339.880301

RE(NPDR)

25

13362

534.48

149.01

LE(NPDR)

25

13362

534.48

138.093333

ANOVA

Source of Variation

SS

df

MS

F

P-value

F crit

Between Groups

6.7689

3

2.2563

0.00743337

0.999117

2.646014

Within Groups

66171.01

218

303.5368

Total

66177.78

221

[i] Anova: Single Factor

Calculated value of F (0.007433) <tabulated value of F (2.646), it is inferred that there is no significant difference in CCT values among mild, moderate & severe NPDR groups, since p=0.999 >0.05.

Table 8

Proportion of NPDR patients over diabetic population

25/86

0.290698

Proportion of PDR patients over diabetic population

10/86

0.116279

Figure 3

Mean CCT of mild, moderate and severe NPDR and PDR Association between PDR and CCT

https://typeset-prod-media-server.s3.amazonaws.com/article_uploads/e724804d-7070-4aeb-9ea4-fbc5b35fce25/image/4dfd7fb8-3b52-495c-a3de-6213a70bafa5-uimage.png

Table 9

Comparison of mean CCT between diabetics with PDR and diabetics without PDR

Summary

Groups

Count

Sum

Average

Variance

RE

86

45929

534.0581

357.5378

LE

86

45955

534.3605

339.8803

RE(PDR)

10

5638

563.8

247.2889

LE(PDR)

10

5641

564.1

217.8778

ANOVA

Source of Variation

SS

df

MS

F

P-value

F crit

Between Groups

15851.83

3

5283.945

15.65193

3.96E-09

2.652646

Within Groups

63467.03

188

337.5906

Total

79318.87

191

[i] Anova: Single Factor

Calculated value of f (15.651)>>tabulated value of f (2.652), it is inferred that there is significant difference in CCT values of PDR group in comparison with the population since p=0.0000000039 <0.05.

Table 10

Comparison of mean CCT between males and females

Summary

Groups

Count

Sum

Average

Variance

RE(M)

95

50562

532.2316

316.8607

LE(M)

95

50589

532.5158

301.3588

RE(FM)

73

38488

527.2329

343.2367

LE(FM)

73

38550

528.0822

318.382

ANOVA

Source of Variation

SS

Df

MS

F

P-value

F crit

Between Groups

1866.46

3

622.1535

1.953253

0.120841

2.631811

Within Groups

105749.2

332

318.5216

Total

107615.6

335

[i] Anova: Single Factor

Calculated value of F (1.95) < tabulated value of F (2.63), it is inferred that there no significant difference in CCT values of male group in comparison with the female group. However based on the above graph, male group has slightly larger value of CCT average compared to that of female group, since p=0.12 >0.05.

Figure 4

Gender vs CCT

https://typeset-prod-media-server.s3.amazonaws.com/article_uploads/e724804d-7070-4aeb-9ea4-fbc5b35fce25/image/6f89007a-ff02-4271-b4f8-6d3f0b3d46ae-uimage.png

Table 11

Comparison of CCT between male and female diabetics

Summary

Groups

Count

Sum

Average

Variance

RE(M)

52

27842

535.4231

422.2881

LE(M)

52

27843

535.4423

422.4476

RE(FM)

34

18087

531.9706

260.8779

LE(FM)

34

18112

532.7059

217.9109

ANOVA

Source of Variation

SS

df

MS

F

P-value

F crit

Between Groups

402.9165

3

134.3055

0.383199

0.765241

2.658399

Within Groups

58881.55

168

350.4854

Total

59284.47

171

[i] Anova: Single Factor

Calculated value of F (0.38) < tabulated value of F (2.66), it is inferred that there no significant difference in CCT values of diabetic male group in comparison with the diabetic female group. However based on the graph male group has larger variance of CCT compared to that of female group. There is no significant difference in averages CCT’s of diabetic male and female group since p=0.76 >0.05.

Figure 5

Gender vs CCT

https://typeset-prod-media-server.s3.amazonaws.com/article_uploads/e724804d-7070-4aeb-9ea4-fbc5b35fce25/image/22afb42e-96ae-4cdc-9479-cb8e9209c7a7-uimage.png

Table 12

Correlation between age and CCT

Age

RE

Age

1

RE

-0.26541

1

Correlation coefficient here is -0.2654. It indicates that these two variables have poor inverse correlation.

Table 13

Correlation between age and CCT

LE

Age

LE

1

Age

-0.27094

1

Correlation coefficient here is -0.27094. It indicates that these two variables have poor inverse correlation.

Table 14

Comparison of mean CCT among diabetics ≤45 years, 46-60 years and >60 years

Summary

Groups

Count

Sum

Average

Variance

RE(Early Dia)

12

6554

546.1667

205.0606

LE(Early Dia)

12

6549

545.75

232.2045

RE(Mid Dia)

37

19733

533.3243

350.2252

LE(Mid Dia)

37

19757

533.973

335.6937

RE(Elderly Dia)

37

19642

530.8649

371.3979

LE(Elderly Dia)

37

19649

531.0541

341.2192

ANOVA

Source of Variation

SS

Df

MS

F

P-value

F crit

Between Groups

4127.251

6

687.8752

2.057744

0.060879

2.153911

Within Groups

55157.21

165

334.2861

Total

59284.47

171

[i] Anova: Single Factor

Calculated value of F (2.057) < tabulated value of F (2.153), it is inferred that there is no significant difference in CCT values of different age groups and by looking at the average CCT’s, elderly diabetic group has lesser CCT average compared to early diabetic groups, since p=0.060 >0.05.

Figure 6

Mean CCT of different age groups of diabetic patients

https://typeset-prod-media-server.s3.amazonaws.com/article_uploads/e724804d-7070-4aeb-9ea4-fbc5b35fce25/image/742db072-4675-41db-8d13-8a14a92a5fac-uimage.png

Table 15

Association between diabetic CCT(RE) and RBS

RE

RBS

RE

1

RBS

0.046404194

1

Correlation co-efficient here is 0.046404 is an indication that these two variables are having poor proportion correlation.

Table 16

Association between diabetic CCT(RE) and FBS

RE

FBS

RE

1

FBS

0.163762

1

Correlation coefficient here it is 0.163762 is an indication that these two variables are having considerable proportion correlation.

Here positive correlation of 0.163 indicates 1.63% increase in FBS will result in 10% increase in CCT (RE).

Table 17

Association between diabetic CCT(RE) and PPBS

RE

PPBS

RE

1

PPBS

0.037918

1

Correlation coefficient here is 0.037918 is an indication that these two variables are having poor proportion correlation.

Table 18

Association between CCT(RE) diabetic and HbA1C

RE

HbA1C

RE

1

HbA1C

0.046277

1

Correlation coefficient here it is 0.046277 is an indication that these two variables are having poor proportion correlation.

Discussion

In our present study, mean CCT in diabetics was 534.0581µ in right eye and 534.3605µ in left eye and in non-diabetics it was 525.8659µ in right eye and 526.6341µ in the left eye. Since calculated F value (5.78) > tabulated F value (2.63), it is inferred that there is significant difference (increase in CCT value in diabetic group compared to non-diabetic group; P = 0.000726 <0.05 by ANOVA test). This is in accordance with the studies reported by Busted N et al who found that diabetic corneas were significantly thicker than normal corneas in a sample size of 81 diabetic subjects.12 Ozdamar Y et al. in 2010 also reported that the CCTs of diabetic patients were thicker than that of normal subjects.13 Storr-Paulsen et al. studied 107 patients with T2DM and 128 nondiabetic controls and concluded that CCT was increased among T2DM patients compared to controls.14

In our study, there is no significant difference in mean CCT values between right eye and left eye among diabetics≤10 years duration (calculated F value 0.0106<tabulated F value 3.946; P value 0.918004 >0.05). Also, there is no significant difference in mean CCT between right eye and left eye among diabetics>10 years duration (calculated F value 0.0025 <tabulated F value 3.963; P value 0.960 >0.05).

Effect of duration of diabetes on CCT was studied by Lee et al. who reported that CCT was significantly higher for diabetes of over 10 years’ duration than for diabetes of under 10 years’ duration.15 In our study also mean CCT in subjects with diabetes of more than10 years duration was higher(537µ) than those having it for ≤10 years(531µ), but the difference was not statistically significant. (calculated F value 1.220 < tabulated F value 2.658; P=0.303> 0.05).

In the current study, no significant difference was found in CCT between 3 diabetic subgroups i.e., those with mild NPDR, moderate NPDR and severe NPDR (calculated F value 0.007433 < tabulated F value 2.646; P=0.999 >0.05). Busted et al.12 and Wiemer et al.16 also found that CCT increased in DM regardless of the severity of retinal disease.

In our study, we found a statistically significant difference in CCT between diabetics with PDR and diabetics without PDR (CCT was much thicker among diabetics with PDR; calculated F value 15.651 >> tabulated F value 2.652; P=0.0000000039 <0.05). Ozdamar et al. reported that patients with PDR had thicker CCT than those with NPDR and no retinopathy; however, the difference was not statistically significant.13 In this study (both diabetics and non-diabetics), mean CCT of males (532.2µ) is greater than mean CCT in females (527.2µ), but difference is not statistically significant (calculated F value 1.95 < tabulated F value 2.63; P=0.12 >0.05).

Mean CCT for male subjects in diabetic group in present study (535.4µ) was higher when compared to female subjects in diabetic group (531.9µ). However, difference was not statistically significant between the two groups (calculated F value 0.38 < tabulated F value 2.66; P =0.76>0.05). Another study done for Indian eyes have reported significantly higher CCT in males (515.6± 33.8µ) than females (508.0 ± 32.8µ) with p value 0.001.17

We observed a decrease in CCT with age in both diabetic and non-diabetic groups. However, the correlation was a poor inverse correlation.

For right eye and -0 27094 for left eye

In this study, we did not observe any significant difference in mean CCT values among diabetics of different age groups (diabetics≤45 years of age, diabetics > 46 years and ≤60 years, diabetics>60 years), as calculated F value 2.057 < tabulated F value 2.153; P =0.060> 0.05.

We observed a poor positive correlation between RBS, PPBS, HbA1C and CCT in T2DM. This is probably due to inclusion of study subjects in our study whose glycemic status is relatively under control. Storr Paulsen et al,2 in their study, reported that HbA1c did not have any impact on the CCT. McNamara et al.18 observed positive correlation between HbA1c level and CCT in T1DM but reported thicker corneas in diabetics but found no direct correlation with HbA1c level in T2DM similar to our study. This observation was reinforced by Yasgan S et al.19

Another study, Mehmet et al20 reported that diabetic patients with HbA1c levels > 7% had thicker corneas than patients with HbA1c levels < 7% (P = 0.021).

Increase in FBS showed an increase in CCT. We found a positive correlation between FBS and CCT in T2DM patients in our study. A position correlation of 0.163 was obtained, which means that 1.63% increase in FBS will result in 10% increase in CCT.

Conclusion

  1. Diabetics showed a higher CCT as compared to non-diabetics.

  2. Diabetics with PDR showed a higher CCT as compared to diabetics without PDR.

  3. Age of diabetics irrespective of age did not have significant effect on CCT. Elderly diabetics showed a relatively lesser CCT.

  4. There is no statistically significant difference in CCT between diabetics of ≤10 years duration and diabetics >10 years duration, but diabetics >10 years have a relatively higher CCT.

  5. CCT is not affected by the severity of NPDR.

  6. There is no statistically significant difference in CCT between males and females in diabetics and non-diabetics.

  7. Increase in CCT was observed with increased FBS values.

  8. Henceforth, it is important to measure the central corneal thickness in all diabetics, as it affects the IOP measurement which is vital for early diagnosis and timely treatment of glaucoma.

Source of Funding

None.

Conflict of Interest

The authors declare no conflict of interest.

References

1 

RP Maurya Diabetic retinopathy: My brief synopsisIndian J Clin Exp Ophthalmol20151418990

2 

SA Kaveeshwar J Cornwall The current state of diabetes mellitus in IndiaAustralas Med J201471458

3 

A Storr-Paulsen A Singh H Jeppesen JC Norregaard J Thulesen Corneal endothelial morphology and central thickness in patients with type II diabetes mellitusActa Ophthalmol201492215860

4 

PE Stanga SR Boyd AM Hamilton Ocular manifestations of diabetes mellitusCurr Opin Ophthalmol1999106483910.1097/00055735-199912000-00018

5 

VS Jeganathan JJ Wang TY Wong Ocular associations of diabetes other than diabetic retinopathyDiabetes.Care2008319190512

6 

M Itoi T Nakamura K Mizobe Y Kodama N Nakagawa M Itoi Specular microscopic studies of the corneal endothelia of Japanese diabetesCornea19898126

7 

AM Roszkowska CG Tringali P Colosi CA Squeri G Ferreri Corneal endothelium evaluation in type I and type II diabetes mellitusOphthalmologica1999213425861

8 

K Inoue S Kato Y Inoue S Amano T Oshika The corneal endothelium and thickness in type II diabetes mellitusJpn J Ophthalmol20024616574

9 

S Morikubo Y Takamura E Kubo S Tsuzuki Y Akagi Corneal changes after small-incision cataract surgery in patients with diabetes mellitusArch Ophthalmol200412279669

10 

PL Kaufman FH Adler LA Levin A Alm Adler’s Physiology of the EyeElsevier Health Sciences2011810

11 

DH Su TY Wong WL Wong SM Saw DT Tan SY Shen Diabetes, hyperglycemia, and central corneal thickness: the Singapore Malay StudyOphthalmology200811569648

12 

N Busted T Olsen O Schmitz Clinical observations on the corneal thickness and the corneal endothelium in diabetes mellitusBr J Ophthalmol1981651068790

13 

Y Ozdamar B Cankaya S Ozalp G Acaroglu JM Karakaya SS Ozkan Is There a Correlation Between Diabetes Mellitus and Central Corneal Thickness?J Glaucoma20101996136

14 

RP Maurya Diabetic macular edema: An overview2019512

15 

JS Lee BS Oum HY Choi JE Lee BM Cho Differences in corneal thickness and corneal endothelium related to duration in DiabetesEye20052033158

16 

NGM Wiemer M Dubbelman PJ Kostense PJ Ringens BCP Polak The Influence of Chronic Diabetes Mellitus on the Thickness and the Shape of the Anterior and Posterior Surface of the CorneaCornea200726116570

17 

L Larsson WM Bourne JM Pach RF Brubaker Structure and function of the corneal endothelium in diabetes mellitus type i and type iiArch Ophthalmol19961141914

18 

NA Mcnamara RJ Brand KA Polse WM Bourne Corneal function during norma l and high serum glucose levels in diabetesInvest Ophthalmol Vis Sci1998391317

19 

S Yazgan U Celik H Kaldırım O Ayar A Elbay V Aykut Evaluation of the relationship between corneal biomechanic and HbA1C levels in type 2 diabetes patientsClin Ophthalmol Auckl NZ20148154953

20 

MÖ Zengin Z Özbek G Arikan İ Durak AO Saatci Does central corneal thickness correlate with haemoglobin A1c level and disease severity in diabetes type II?Turk J Med Sci201040567580http://journals.tubitak.gov.tr/medical/issues/sag-10-40-5/sag-40-5-1-0905-34.pdf



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Article type

Original Article


Article page

554-561


Authors Details

Chinnangolla Viveknandini Reddy*, M H Reddy


Article History

Received : 05-12-2020

Accepted : 22-01-2021

Available online : 30-09-2021


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