Journal of Clinical and Diagnostic Research, ISSN - 0973 - 709X

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On Sep 2018




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On Aug 2018




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Dr. Arundhathi. S
MBBS, MD (Pathology),
Sanjay Gandhi institute of trauma and orthopedics,
Bengaluru.
On Aug 2018




Dr. Mamta Gupta,
"It gives me great pleasure to be associated with JCDR, since last 2-3 years. Since then I have authored, co-authored and reviewed about 25 articles in JCDR. I thank JCDR for giving me an opportunity to improve my own skills as an author and a reviewer.
It 's a multispecialty journal, publishing high quality articles. It gives a platform to the authors to publish their research work which can be available for everyone across the globe to read. The best thing about JCDR is that the full articles of all medical specialties are available as pdf/html for reading free of cost or without institutional subscription, which is not there for other journals. For those who have problem in writing manuscript or do statistical work, JCDR comes for their rescue.
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Reviewing articles is no less a pain staking process and requires in depth perception, knowledge about the topic for review. It requires time and concentration, yet I enjoy doing it. The JCDR website especially for the reviewers is quite user friendly. My suggestions for improving the journal is, more strict review process, so that only high quality articles are published. I find a a good number of articles in Obst. Gynae, hence, a new journal for this specialty titled JCDR-OG can be started. May be a bimonthly or quarterly publication to begin with. Only selected articles should find a place in it.
An yearly reward for the best article authored can also incentivize the authors. Though the process of finding the best article will be not be very easy. I do not know how reviewing process can be improved. If an article is being reviewed by two reviewers, then opinion of one can be communicated to the other or the final opinion of the editor can be communicated to the reviewer if requested for. This will help one’s reviewing skills.
My best wishes to Dr. Hemant Jain and all the editorial staff of JCDR for their untiring efforts to bring out this journal. I strongly recommend medical fraternity to publish their valuable research work in this esteemed journal, JCDR".



Dr. Mamta Gupta
Consultant
(Ex HOD Obs &Gynae, Hindu Rao Hospital and associated NDMC Medical College, Delhi)
Aug 2018




Dr. Rajendra Kumar Ghritlaharey

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Writing is the representation of language in a textual medium i e; into the words and sentences on paper. Quality medical manuscript writing in particular, demands not only a high-quality research, but also requires accurate and concise communication of findings and conclusions, with adherence to particular journal guidelines. In medical field whether working in teaching, private, or in corporate institution, everyone wants to excel in his / her own field and get recognised by making manuscripts publication.


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Salient features of the JCDR: It is a biomedical, multidisciplinary (including all medical and dental specialities), e-journal, with wide scope and extensive author support. At the same time, a free text of manuscript is available in HTML and PDF format. There is fast growing authorship and readership with JCDR as this can be judged by the number of articles published in it i e; in Feb 2007 of its first issue, it contained 5 articles only, and now in its recent volume published in April 2011, it contained 67 manuscripts. This e-journal is fulfilling the commitments and objectives sincerely, (as stated by Editor-in-chief in his preface to first edition) i e; to encourage physicians through the internet, especially from the developing countries who witness a spectrum of disease and acquire a wealth of knowledge to publish their experiences to benefit the medical community in patients care. I also feel that many of us have work of substance, newer ideas, adequate clinical materials but poor in medical writing and hesitation to submit the work and need help. JCDR provides authors help in this regards.
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Indexation and online availability: Indexation transforms the journal in some sense from its local ownership to the worldwide professional community and to the public.JCDR is indexed with Embase & EMbiology, Google Scholar, Index Copernicus, Chemical Abstracts Service, Journal seek Database, Indian Science Abstracts, to name few of them. Manuscriptspublished in JCDR are available on major search engines ie; google, yahoo, msn.
In the era of fast growing newer technologies, and in computer and internet friendly environment the manuscripts preparation, submission, review, revision, etc and all can be done and checked with a click from all corer of the world, at any time. Of course there is always a scope for improvement in every field and none is perfect. To progress, one needs to identify the areas of one's weakness and to strengthen them.
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Every one of us: authors, reviewers, editors, and publisher are responsible for enhancing the stature of the journal. I wish for a great success for JCDR."



Thanking you
With sincere regards
Dr. Rajendra Kumar Ghritlaharey, M.S., M. Ch., FAIS
Associate Professor,
Department of Paediatric Surgery, Gandhi Medical College & Associated
Kamla Nehru & Hamidia Hospitals Bhopal, Madhya Pradesh 462 001 (India)
E-mail: drrajendrak1@rediffmail.com
On May 11,2011




Dr. Shankar P.R.

"On looking back through my Gmail archives after being requested by the journal to write a short editorial about my experiences of publishing with the Journal of Clinical and Diagnostic Research (JCDR), I came across an e-mail from Dr. Hemant Jain, Editor, in March 2007, which introduced the new electronic journal. The main features of the journal which were outlined in the e-mail were extensive author support, cash rewards, the peer review process, and other salient features of the journal.
Over a span of over four years, we (I and my colleagues) have published around 25 articles in the journal. In this editorial, I plan to briefly discuss my experiences of publishing with JCDR and the strengths of the journal and to finally address the areas for improvement.
My experiences of publishing with JCDR: Overall, my experiences of publishing withJCDR have been positive. The best point about the journal is that it responds to queries from the author. This may seem to be simple and not too much to ask for, but unfortunately, many journals in the subcontinent and from many developing countries do not respond or they respond with a long delay to the queries from the authors 1. The reasons could be many, including lack of optimal secretarial and other support. Another problem with many journals is the slowness of the review process. Editorial processing and peer review can take anywhere between a year to two years with some journals. Also, some journals do not keep the contributors informed about the progress of the review process. Due to the long review process, the articles can lose their relevance and topicality. A major benefit with JCDR is the timeliness and promptness of its response. In Dr Jain's e-mail which was sent to me in 2007, before the introduction of the Pre-publishing system, he had stated that he had received my submission and that he would get back to me within seven days and he did!
Most of the manuscripts are published within 3 to 4 months of their submission if they are found to be suitable after the review process. JCDR is published bimonthly and the accepted articles were usually published in the next issue. Recently, due to the increased volume of the submissions, the review process has become slower and it ?? Section can take from 4 to 6 months for the articles to be reviewed. The journal has an extensive author support system and it has recently introduced a paid expedited review process. The journal also mentions the average time for processing the manuscript under different submission systems - regular submission and expedited review.
Strengths of the journal: The journal has an online first facility in which the accepted manuscripts may be published on the website before being included in a regular issue of the journal. This cuts down the time between their acceptance and the publication. The journal is indexed in many databases, though not in PubMed. The editorial board should now take steps to index the journal in PubMed. The journal has a system of notifying readers through e-mail when a new issue is released. Also, the articles are available in both the HTML and the PDF formats. I especially like the new and colorful page format of the journal. Also, the access statistics of the articles are available. The prepublication and the manuscript tracking system are also helpful for the authors.
Areas for improvement: In certain cases, I felt that the peer review process of the manuscripts was not up to international standards and that it should be strengthened. Also, the number of manuscripts in an issue is high and it may be difficult for readers to go through all of them. The journal can consider tightening of the peer review process and increasing the quality standards for the acceptance of the manuscripts. I faced occasional problems with the online manuscript submission (Pre-publishing) system, which have to be addressed.
Overall, the publishing process with JCDR has been smooth, quick and relatively hassle free and I can recommend other authors to consider the journal as an outlet for their work."



Dr. P. Ravi Shankar
KIST Medical College, P.O. Box 14142, Kathmandu, Nepal.
E-mail: ravi.dr.shankar@gmail.com
On April 2011
Anuradha

Dear team JCDR, I would like to thank you for the very professional and polite service provided by everyone at JCDR. While i have been in the field of writing and editing for sometime, this has been my first attempt in publishing a scientific paper.Thank you for hand-holding me through the process.


Dr. Anuradha
E-mail: anuradha2nittur@gmail.com
On Jan 2020

Important Notice

Original article / research
Year : 2022 | Month : May | Volume : 16 | Issue : 5 | Page : NC01 - NC04 Full Version

Macular Thickness- An Early Predictor of Diabetic Macular Oedema


Published: May 1, 2022 | DOI: https://doi.org/10.7860/JCDR/2022/53235.16324
Chandrika Sareddy, Shubha Nagpal, Deepa Muzumdar

1. Senior Resident, Department of Ophthalmology, Bharati Vidyapeeth Medical College, Pune, Maharashtra, India. 2. Professor, Department of Ophthalmology, Bharati Vidyapeeth Medical College, Pune, Maharashtra, India. 3. Associate Professor, Department of Ophthalmology, Bharati Vidyapeeth Medical College, Pune, Maharashtra, India.

Correspondence Address :
Shubha Nagpal,
Flat no. B- 2083, Clover Palisades, 27 NIBM Road, Pune, Maharashtra, India.
E-mail: shubha.nagpal@gmail.com

Abstract

Introduction: Diabetic Macular Oedema (DME) accounts for visual morbidity in about three fourth of Diabetic Retinopathy (DR) patients. Traditional examination on 90D slit lamp or stereoscopic fundus photograph may not be able to identify early maculopathy. Optical Coherence Tomography (OCT) is a sensitive, non invasive modality which may detect early retinal thickness changes in DME.

Aim: To identify any increase in macular thickness in diabetic patients with early DR without any clinically detectable macular oedema.

Materials and Methods: This cross-sectional analytical study was conducted from September 2018 to July 2020 in the Ophthalmology Department at Bharati Vidyapeeth Medical College and Hospital, Pune, Maharashtra, India. A total of 277 eyes of 184 subjects were evaluated. Of these 182 eyes were of diabetic patients (124 patients) and 95 eyes belonged to controls (60 subjects). Amongst the diabetic eyes evaluated, group I consisted of 100 eyes with no evidence of DR and group II consisted of 82 eyes with mild Non Proliferative Diabetic Retinopathy (NPDR). Group III included 95 eyes of non diabetic age matched controls.

Macular thickness was measured using the Topcon 3D OCT-1 Maestro System. The central 1mm macular thickness of the three groups was analysed and compared using student's t-test.

Results: The mean Central Macular Thickness (CMT) showed no statistically significant difference (p-value<0.7) between group III (222.4±10.8) and group I (223.0±13.7 μm). However, a significant increase in CMT (p-value<0.0001 and, p-value<0.0006) was noted in group II (230.7±15.6 μm) when compared with group III (222.4±10.8 μm) and group I (223.0±13.7 μm). Macular thickness amounting to Subclinical Macular Oedema (SCME) was seen in only in 6.09% of eyes in group II, five eyes of the total number of 82 eyes with mild NPDR.

Conclusion: Increased CMT was detected in mild NPDR patients on Optical Coherence Topography (OCT) even without any clinical evidence of macular oedema. Since eyes with SCME, diagnosed at base line assessment, are at a higher risk of developing clinical macular oedema subsequently, it is recommend that a base line OCT be performed in all patients detected to have mild NPDR irrespective of the absence of clinical findings suggestive of DME.

Keywords

Central macular thickness, Diabetic macular oedema, Optical coherence tomography

The burden of diabetes mellitus is an increasing trend both worldwide and in India. According to the international diabetes federation, the total number of people affected by diabetes mellitus in 2019 was 463 million. It was estimated that by 2030 the number will be 578 million and by 2045 it will increase to 700 million. India stands second in rank with an estimated number of 77 million diabetics (1).

DME accounts for visual morbidity in about three fourth of DR patients (2). The global prevalence of Diabetic Macular Oedema (DME) was estimated to be 7.4% in 2012 (3). Because of its special anatomical features like, loose intercellular adhesions and absence of Müller cells in the fovea, the macula is more susceptible for fluid and proteins accumulation leading to oedema, than other areas of the retina (2). Traditional examination on slit lamp with 90D or stereoscopic fundus photographs may not be able to identify minimal changes in the retinal thickness. Optical Coherence Tomography (OCT) is a sensitive, non invasive modality for diagnosing and classifying DME (4),(5).

Several studies have been conducted to assess macular thickness in patients with Diabetes Mellitus (DM) with and without Diabetic Retinopathy (DR). The results have been variable. A prospective observational study on mild Non Proliferative Diabetic Retinopathy (NPDR) patients compared macular central subfield and central point thickness in patients with mild NPDR to normative population database of Carl Zeiss and found that both are thicker in mild NPDR eyes (p-value<0.001) (6). However, Srinivasan S et al., observed that the retinal thickness in both central and perifoveal zone of diabetes mellitus patients with no DR and mild NPDR did not show any significant difference when compared with the control group (p-value=0.27and p-value>0.41 respectively). Instead, a significant decrease in Parafoveal thickness was noted in diabetes mellitus patients with mild NPDR (p-value<0.02) (7). Murgesan S et al., conducted a prospective case control study to compare Central Macular Thickness (CMT) between diabetes mellitus patients without DR and non diabetic controls and observed that the study group showed significantly thinner central macula (p-value<0.001) than the controls (8). In view of these disparate findings, a study to analyse macular thickness in Diabetics with and without DR was considered relevant.

It was also found that patients with sub clinical macular oedema in the central subfield at baseline showed a 12-fold risk of progression to Center Involving Macular Oedema (CIME) compared to patients without SCME at base line (9). This study was undertaken to quantitatively measure the CMT in diabetics without DR and those with mild NPDR without any clinically detectable macular oedema, with the purpose of ascertaining if it could be considered as an early predictor of DME.

Material and Methods

This cross-sectional analytical study was conducted from September 2018 to July 2020 in the Ophthalmology Department of the Bharati Vidyapeeth Medical College and Hospital, Pune, Maharashtra, India, after approval from the College ethics committee (BVDUMC/IEC/64 dated07/09/2018).

Sample size calculation: Sample size was calculated using Statulator online sample size calculator using two different means (7). Assuming the mean central foveal thickness in control group as 253 and diabetic group as 246 and standard deviation of 25, alpha error of 5% and 80% power, the sample size was calculated to be 154 (7). Hence, a total of 184 subjects were enrolled in the study.

After obtaining their informed consent, 124 Type II diabetics reporting to the Ophthalmology Department aged between 20-70 years were included in this study.

Inclusion criteria: Patients diagnosed with DM for more than 1 year and up to 20 year were included. Glycaemic control and treatment modalities were not considered during enrollment of the study subjects, since it was a single point assessment of macular thickness which was being evaluated. Sixty age and sex matched, healthy non diabetics were enrolled as controls.

Exclusion criteria: Patients with DM with moderate to severe NPDR, proliferative diabetic retinopathy or clinically significant macular oedema were not included in the study. Subjects with any other macular pathology, previous ocular surgeries or intravitreal injections, laser therapy and ocular infections were excluded. Patients with media opacities preventing good OCT evaluation were also excluded from the study.

Procedure

All the 124 diabetic study participants were subjected to a complete ophthalmic examination including-BCVA, anterior segment evaluation, fundus examination with 90 D lens and intra ocular pressure. Total 60 age and sex matched controls were similarly evaluated. Based on the clinical evaluation of the retina by 90D patients were further subdivided into three groups.

• Group I (n=60, 100 eyes)- Diabetic patients with no evidence of DR.
• Group II (n=64, 82 eyes)- Diabetics with mild NPDR Criterion for this grouping was according to the Early Treatment Diabetic Retinopathy Study (ETDRS) classification level 20-35 microaneurysms and microaneurysms with few retinal hemorrhages (10).
• Group III (n=60, 95 eyes)- Controls group.

Optical Coherence Tomography (OCT): OCT was performed on all the subjects using Topcon 3D OCT-1 Maestro System (TOPCON, Japan) machine. This Spectral Domain-OCT (SD-OCT) has a scan speed of 50,000 A- scans per second, a scan depth of 2.3 μ, axial resolution of 5-6 μ and transverse resolution of 20 μ. The 3D- macula acquisition protocol consisting of 512 A-scans and 128 B-scans each (6.0x6.0mm-512x128) was performed. Each scan was inspected for centration and image quality. Scans with signal strength less than 30 were discarded. The automated analysis report consists of the measurement of the macular thickness in different Early Treatment Diabetic Retinopathy Study (ETDRS) map locations, including the central area of 1 mm diameter, and 2 concentric rings around the fovea. These consist of an inner ring of 3 mm diameter and an outer ring of 6 mm diameter. Each ring is further divided into four subfields (Table/Fig 1). The thickness value of the central 1mm circular area was used for analysis. No manual measurements were made.

Statistical Analysis

The data was tabulated and analysed using the software Statistical Package for the Social Science (SPSS) version 22.0. Student's t-test was used to compare the mean CMT values between the groups. A p-value <0.05 was considered as significant.

Results

Of the 184 subjects evaluated, 109 were males and 75 were females. Of 277 eyes included in the study, 100 eyes were in group I, 82 eyes in group II and 95 eyes formed the control group. The age of study subjects ranged from 20-70 years. Demographic details are as per (Table/Fig 2).

CMT in group I varied from 195-251 μm with a mean of 223.0±13.7 μm. In group II the values ranged from 202-270 μm with a mean value of 230.7±15.6 μm and in group III the range was from 195-244 μm with a mean of 222.4±10.7 μm (Table/Fig 3),(4).

SCME in the present study was seen only in 6.09% of eyes in group II (5 eyes of the total number of 82 eyes with mild NPDR).

Males were found to have a significantly thicker central macula when compared to females across all groups, with p-values of 0.002, 0.0001 and 0.005, respectively (Table/Fig 5).

The mean CMT in group I (223.0±13.7 μm) and group III (222.4±10.7 μm) was not found to be significantly different with a p-value of 0.7. However, a significant difference when mean CMT in group II was compared against group III (p-value=0.0001). A similar statistical significant difference was also noted between mean CMT values in group I and group II (p-value=0.0006) (Table/Fig 6).

Discussion

Diabetic Retinopathy (DR) remains high on the list of causes attributable for visual morbidity amongst individuals in the group of 50 years and above (11), DME being the primary pathology for the same in about 75% of patients with DR (12). The ETDRS study has observed that central DME was responsible for the risk of moderate vision loss in 32%of patients (12). Since, the visual loss is slow and progressive patients may be detected to have advanced retinal and macular changes even on initial presentation to the hospital resulting in a poor visual prognosis despite treatment.

For the DME to be clinically detected by conventional 90D examination, the macular thickness should be >299 μ (13). OCT scanning of the macula enables increase in macular thickness to be assessed early to establish the presence of SCME. DRCR.net defined SCME as center point thickness between 225 to 299 μm on Stratus OCT (14). Whereas on SD-OCT, SCME is considered as retinal thickness >260 μm to <290 μm in women and >275 μm to <305 μm in men (15).

Studies have established that patients with SCME have an increased risk of developing DME. Piers I et al., evaluated patients with mild NPDR for a period of 2 years and found the risk of developing DME was 3.6 times higher in those who had SCME at base line (16). A similar study by Lobo C et al., at Portugal and LVPEI Hyderabad on diabetics with mild NPDR observed a 12 times higher risk of DME in patients diagnosed with SCME at initial examination (9).

The current study showed, the mean thickness of the central 1000 μ at the macula of 100 eyes of diabetics with no evidence of DR, 82 eyes of patients with early NPDR and compared these values with 95 eyes belonging to age matched controls. The mean CMT value was observed to be 223.0±13.7 μm in the eyes with no DR, 230.7± 15.6 μ min eyes with mild DR and 222.4±10.7 μm in controls. The mean CMT in controls was similar to that observed by Adhi M et al., and Gautam M et al., (227.19±29.9.94 μm and 226.4±22.5 μm) in studies conducted on normal population in Pakistan and in India, respectively (17),(18). The mean CMT in group I and group II of the present study were also similar to the mean CMT in an Egyptian study on similar groups (221.2±24.2 μm and 231.3±29.3 μm, respectively) (19).

Higher values of mean CMT were seen in males as compared to females across all groups. A study of macular thickness using spectral domain OCT in healthy Indian population conducted by Gautam M et al., also found macular thickness to be more in males (229.8±21.4 μm) than in females (220.7±23.1 μm) (18). Srinivasan S et al., in Australia, and Bressler NM et al., in United States of America who studied diabetic patients with and without DR also noted that males have a significantly thicker macula than females (7),(20).

No significant difference (p-value=0.7) was noted in the mean CMT between group I and controls. Similar findings have been reported by Srinivasan S et al., and Demir M et al., (7),(21). Bressler NM et al., in their study on diabetics with and without DR also noted no difference between mean macular thickness in controls and diabetics with no retinal changes of DR (20). This could suggest that central macular involvement may not precede the development of clinically evident retinopathy.

Authors observed a definitely thicker mean CMT in group II, i.e., eyes with mild NPDR (230.7±15.6 μm). The value was higher than that observed in studies conducted by Piers I et al., (219.2±25 μ) and lower than those by Srinivasan S et al., (245±25 μm) (6),(7). This may be due to variance in the populations studied (Caucasians) as well as different OCT machines used. Pires I et al., used a time domain Stratus OCT and Srinivasan S et al., used a RTVue-100 OCT (6),(7). There was a significant difference seen on comparison of the mean CMT of group II with controls and group I; p-value=0.0001 and p-value=0.0006 respectively. In eyes with mild NPDR, presence of vessel changes and microaneurysms suggest the onset of microangiopathy. The vasogenic oedema resulting from vascular damage and subsequent alteration of the blood-retinal barrier, which is mainly associated with an abnormal accumulation of extracellular fluid, can, explain the thickening observed in the central macula (22).

SCME in the present study was seen in 5 eyes (6.09%) in group II (early NPDR). Piers I et al., reported an incidence of 9.3% in mild NPDR patients (16). Ribiro L et al., studied a larger group (158 patients) of mild NPDR patients and reported an incidence as high as 30% (23).

Limitation(s)

This study was conducted on diabetic patients attending the Ophthalmology Outpatient Department of a tertiary care hospital. The number of eyes evaluated was hence limited and additional studies on larger numbers of patients may further confirm these findings. This was a single point observational study, so authors did not consider other factors like duration of DM or glycaemic control that can affect the CMT. Follow-up of patients with increased CMT to assess the development of CSME is ongoing and was not a part of this study.

Conclusion

In this study we evaluated the mean CMT on OCT of diabetics with and without early NPDR and found a significantly increased macular thickness in patients with early NPDR. Though, SCME was seen in 6.09% of eyes in group II, the mean CMT was significantly more. This reveals that there can be minute changes at the macula in the early stages of DR, which are not evident on indirect ophthalmoscopy examination but can be detected on SDOCT. Thus, it can be concluded that there might be a subgroup of eyes that may have an increase in CMT in the early stage of DR even if fundus examination reveals no signs of DME/Clinically-Significant Macular Oedema (CSME). Macular scans on OCT as a baseline evaluation of all eyes with early DR, irrespective of their glycaemic control, will need to be performed to diagnose such patients, so as to enable a closer follow-up and early treatment, if necessary, for preventing visual morbidity. However, there is a need for further studies with higher resolution OCT like swept source to confirm this finding in a large population.

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DOI and Others

DOI: 10.7860/JCDR/2022/53235.16324

Date of Submission: Nov 10, 2021
Date of Peer Review: Jan 19, 2022
Date of Acceptance: Feb 12, 2022
Date of Publishing: May 01, 2022

AUTHOR DECLARATION:
• Financial or Other Competing Interests: None
• Was Ethics Committee Approval obtained for this study? Yes
• Was informed consent obtained from the subjects involved in the study? Yes
• For any images presented appropriate consent has been obtained from the subjects. NA

PLAGIARISM CHECKING METHODS:
• Plagiarism X-checker: Nov 13, 2021
• Manual Googling: Feb 03, 2022
• iThenticate Software: Feb 09, 2022 (8%)

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