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

Users Online : 285235

AbstractMaterial and MethodsResultsDiscussionConclusionReferencesDOI and Others
Article in PDF How to Cite Citation Manager Readers' Comments (0) Audio Visual Article Statistics Link to PUBMED Print this Article Send to a Friend
Advertisers Access Statistics Resources

Dr Mohan Z Mani

"Thank you very much for having published my article in record time.I would like to compliment you and your entire staff for your promptness, courtesy, and willingness to be customer friendly, which is quite unusual.I was given your reference by a colleague in pathology,and was able to directly phone your editorial office for clarifications.I would particularly like to thank the publication managers and the Assistant Editor who were following up my article. I would also like to thank you for adjusting the money I paid initially into payment for my modified article,and refunding the balance.
I wish all success to your journal and look forward to sending you any suitable similar article in future"



Dr Mohan Z Mani,
Professor & Head,
Department of Dermatolgy,
Believers Church Medical College,
Thiruvalla, Kerala
On Sep 2018




Prof. Somashekhar Nimbalkar

"Over the last few years, we have published our research regularly in Journal of Clinical and Diagnostic Research. Having published in more than 20 high impact journals over the last five years including several high impact ones and reviewing articles for even more journals across my fields of interest, we value our published work in JCDR for their high standards in publishing scientific articles. The ease of submission, the rapid reviews in under a month, the high quality of their reviewers and keen attention to the final process of proofs and publication, ensure that there are no mistakes in the final article. We have been asked clarifications on several occasions and have been happy to provide them and it exemplifies the commitment to quality of the team at JCDR."



Prof. Somashekhar Nimbalkar
Head, Department of Pediatrics, Pramukhswami Medical College, Karamsad
Chairman, Research Group, Charutar Arogya Mandal, Karamsad
National Joint Coordinator - Advanced IAP NNF NRP Program
Ex-Member, Governing Body, National Neonatology Forum, New Delhi
Ex-President - National Neonatology Forum Gujarat State Chapter
Department of Pediatrics, Pramukhswami Medical College, Karamsad, Anand, Gujarat.
On Sep 2018




Dr. Kalyani R

"Journal of Clinical and Diagnostic Research is at present a well-known Indian originated scientific journal which started with a humble beginning. I have been associated with this journal since many years. I appreciate the Editor, Dr. Hemant Jain, for his constant effort in bringing up this journal to the present status right from the scratch. The journal is multidisciplinary. It encourages in publishing the scientific articles from postgraduates and also the beginners who start their career. At the same time the journal also caters for the high quality articles from specialty and super-specialty researchers. Hence it provides a platform for the scientist and researchers to publish. The other aspect of it is, the readers get the information regarding the most recent developments in science which can be used for teaching, research, treating patients and to some extent take preventive measures against certain diseases. The journal is contributing immensely to the society at national and international level."



Dr Kalyani R
Professor and Head
Department of Pathology
Sri Devaraj Urs Medical College
Sri Devaraj Urs Academy of Higher Education and Research , Kolar, Karnataka
On Sep 2018




Dr. Saumya Navit

"As a peer-reviewed journal, the Journal of Clinical and Diagnostic Research provides an opportunity to researchers, scientists and budding professionals to explore the developments in the field of medicine and dentistry and their varied specialities, thus extending our view on biological diversities of living species in relation to medicine.
‘Knowledge is treasure of a wise man.’ The free access of this journal provides an immense scope of learning for the both the old and the young in field of medicine and dentistry as well. The multidisciplinary nature of the journal makes it a better platform to absorb all that is being researched and developed. The publication process is systematic and professional. Online submission, publication and peer reviewing makes it a user-friendly journal.
As an experienced dentist and an academician, I proudly recommend this journal to the dental fraternity as a good quality open access platform for rapid communication of their cutting-edge research progress and discovery.
I wish JCDR a great success and I hope that journal will soar higher with the passing time."



Dr Saumya Navit
Professor and Head
Department of Pediatric Dentistry
Saraswati Dental College
Lucknow
On Sep 2018




Dr. Arunava Biswas

"My sincere attachment with JCDR as an author as well as reviewer is a learning experience . Their systematic approach in publication of article in various categories is really praiseworthy.
Their prompt and timely response to review's query and the manner in which they have set the reviewing process helps in extracting the best possible scientific writings for publication.
It's a honour and pride to be a part of the JCDR team. My very best wishes to JCDR and hope it will sparkle up above the sky as a high indexed journal in near future."



Dr. Arunava Biswas
MD, DM (Clinical Pharmacology)
Assistant Professor
Department of Pharmacology
Calcutta National Medical College & Hospital , Kolkata




Dr. C.S. Ramesh Babu
" Journal of Clinical and Diagnostic Research (JCDR) is a multi-specialty medical and dental journal publishing high quality research articles in almost all branches of medicine. The quality of printing of figures and tables is excellent and comparable to any International journal. An added advantage is nominal publication charges and monthly issue of the journal and more chances of an article being accepted for publication. Moreover being a multi-specialty journal an article concerning a particular specialty has a wider reach of readers of other related specialties also. As an author and reviewer for several years I find this Journal most suitable and highly recommend this Journal."
Best regards,
C.S. Ramesh Babu,
Associate Professor of Anatomy,
Muzaffarnagar Medical College,
Muzaffarnagar.
On Aug 2018




Dr. Arundhathi. S
"Journal of Clinical and Diagnostic Research (JCDR) is a reputed peer reviewed journal and is constantly involved in publishing high quality research articles related to medicine. Its been a great pleasure to be associated with this esteemed journal as a reviewer and as an author for a couple of years. The editorial board consists of many dedicated and reputed experts as its members and they are doing an appreciable work in guiding budding researchers. JCDR is doing a commendable job in scientific research by promoting excellent quality research & review articles and case reports & series. The reviewers provide appropriate suggestions that improve the quality of articles. I strongly recommend my fraternity to encourage JCDR by contributing their valuable research work in this widely accepted, user friendly journal. I hope my collaboration with JCDR will continue for a long time".



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.
The journal has a monthly publication and the articles are published quite fast. In time compared to other journals. The on-line first publication is also a great advantage and facility to review one's own articles before going to print. The response to any query and permission if required, is quite fast; this is quite commendable. I have a very good experience about seeking quick permission for quoting a photograph (Fig.) from a JCDR article for my chapter authored in an E book. I never thought it would be so easy. No hassles.
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

"I wish to thank Dr. Hemant Jain, Editor-in-Chief Journal of Clinical and Diagnostic Research (JCDR), for asking me to write up few words.
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.


Authors are the souls of any journal, and deserve much respect. To publish a journal manuscripts are needed from authors. Authors have a great responsibility for producing facts of their work in terms of number and results truthfully and an individual honesty is expected from authors in this regards. Both ways its true "No authors-No manuscripts-No journals" and "No journals–No manuscripts–No authors". Reviewing a manuscript is also a very responsible and important task of any peer-reviewed journal and to be taken seriously. It needs knowledge on the subject, sincerity, honesty and determination. Although the process of reviewing a manuscript is a time consuming task butit is expected to give one's best remarks within the time frame of the journal.
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.
Timely publication of journal: Publication of manuscripts and bringing out the issue in time is one of the positive aspects of JCDR and is possible with strong support team in terms of peer reviewers, proof reading, language check, computer operators, etc. This is one of the great reasons for authors to submit their work with JCDR. Another best part of JCDR is "Online first Publications" facilities available for the authors. This facility not only provides the prompt publications of the manuscripts but at the same time also early availability of the manuscripts for the readers.
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.
It is well said that "happy beginning is half done" and it fits perfectly with JCDR. It has grown considerably and I feel it has already grown up from its infancy to adolescence, achieving the status of standard online e-journal form Indian continent since its inception in Feb 2007. This had been made possible due to the efforts and the hard work put in it. The way the JCDR is improving with every new volume, with good quality original manuscripts, makes it a quality journal for readers. I must thank and congratulate Dr Hemant Jain, Editor-in-Chief JCDR and his team for their sincere efforts, dedication, and determination for making JCDR a fast growing journal.
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 1 mm 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±10.7 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 retinopathy, 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).

The 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 dated 07/09/2018).

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.

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): The 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 (6.0×6.0 mm-512×128) 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 1 mm 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), (Table/Fig 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 two 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).

The 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.

References

1.
International Diabetes Federation. IDF DIABETES ATLAS, 9th Edn. Brussels, Belgium: 2019. Available at: https://www.diabetesatlas.org.
2.
Bandello F, Parodi MB, Lanzetta P, Loewenstein A, Massin P, Menchini F, et al. Diabetic macular oedema. Dev Ophthalmol. 2017;58:102-38. [crossref] [PubMed]
3.
Yau JW, Rogers SL, Kawasaki R, Lamourux EL, Kowalski JW, Bek T, et al. Global prevalence and major risk factors of diabetic retinopathy. Diabetes Care 2012;35(3):556-64. [crossref] [PubMed]
4.
Lattanzio R, Brancato R, Pierro L, Bandello F, Iaccher B, Fiore T, et al. Macular thickness measured by optical coherence tomography (OCT) in diabetic patients. European Journal of Ophthalmology. 2002;12(6):482-87. [crossref] [PubMed]
5.
Sánchez-Tocino H, Alvarez-Vidal A, Maldonado MJ, Moreno-Montañés J, García-Layana A. Retinal thickness study with optical coherence tomography in patients with diabetes. Investigative Ophthalmology & Visual Science. 2002;43(5):1588-94.
6.
Pires I, Santos AR, Nunes S, Lobo C. Macular thickness measured by stratus optical coherence tomography in patients with diabetes type 2 and mild nonproliferative retinopathy without clinical evidence of macular oedema. Ophthalmologica. 2013;229(4):181-86. [crossref] [PubMed]
7.
Srinivasan S, Pritchard N, Sampson GP, Edwards K, Vagenas D, Russell AW, et al. Retinal thickness profile of individuals with diabetes. Ophthalmic and Physiological Optics. 2016;36(2):158-66. [crossref] [PubMed]
8.
Murugesan S, Jha KN, Krishnagopal S, Ezhumalai G. Central macular thickness in diabetics without retinopathy. TNOA Journal of Ophthalmic Science and Research. 2018;56(3):150. [crossref]
9.
Lobo C, Pires I, Alves D, Pappuru R, Ribeiro L, Cunha-Vaz J, et al. Subclinical macular oedema as a predictor of progression to central-involved macular oedema in type 2 diabetes. Ophthalmic Res. 2018;60(1):18-22. [crossref] [PubMed]
10.
Early Treatment Diabetic Retinopathy Study Research Group. Grading diabetic retinopathy from stereoscopic color fundus photographs-an extension of the modified Airlie House classification: ETDRS report number 10. Ophthalmology. 1991;98(5):786-806. [crossref]
11.
Leasher JL, Bourne RR, Flaxman SR, Jonas JB, Keeffe J, Naidoo K, et al. Global estimates on the number of people blind or visually impaired by diabetic retinopathy: A meta-analysis from 1990 to 2010. Diabetes Care. 2016;39(9):1643-49. [crossref] [PubMed]
12.
ETDRS Research Group. Photocoagulation for macular oedema: ETDRS report number 1. Arch Ophthalmol. 1985;103:1796-806. [crossref] [PubMed]
13.
Brown JC, Solomon SD, Bressler SB, Schachat AP, DiBernardo C, Bressler NM. Detection of diabetic foveal oedema: contact lens biomicroscopy compared with optical coherence tomography. Archives of Ophthalmology. 2004;122(3):330-35. [crossref] [PubMed]
14.
Diabetic Retinopathy Clinical Research Network, Bressler N, Miller K, et al. Observational study of subclinical diabetic macular oedema. Eye. 2012;26:833-40. Available from: https://doi.org/10.1038/eye.2012.53. [crossref] [PubMed]
15.
Chalam KV, Bressler SB, Edwards AR, Berger BB, Bressler NM, Glassman AR, et al. Retinal thickness in people with diabetes and minimal or no diabetic retinopathy. Heidelberg Spectralis optical coherence tomography. Invest Ophthalmol Vis Sci. 2012;53(13):8154-61. [crossref] [PubMed]
16.
Pires I, Santos AR, Nunes S, Lobo C, Cunha-Vaz J. Subclinical macular oedema as a predictor of progression to clinically significant macular oedema in type 2 diabetes. Ophthalmologica. 2013;230:201-06. [crossref] [PubMed]
17.
Adhi M, Aziz S, Muhammad K, Adhi MI. Macular thickness by age and gender in healthy eyes using spectral domain optical coherence tomography. PLoS One. 2012;7(5):e37638. [crossref] [PubMed]
18.
Gautam M, Khilnani K, Saxena R. Study of macular thickness using spectral domain optical coherence tomography in healthy indian subjects. Journal of Medical Science and Clinical Research. 2016;4(2):9421-31. [crossref]
19.
Shawky SS, Elagouz MH, Ismail AM, Elhawwary AM. Macular thickness in healthy controls and diabetics without diabetic macular oedema. Egypt Retina J. 2018;5:01-05. [crossref]
20.
Bressler NM, Edwards AR, Antoszyk AN, Beck RW, Browning DJ, Ciardella AP, et al. Retinal thickness on Stratus optical coherence tomography in people with diabetes and minimal or no diabetic retinopathy. American Journal of Ophthalmology. 2008;145(5):894-901. [crossref] [PubMed]
21.
Demir M, Dirim B, Acar Z, Yilmaz M, Sendul Y. Central macular thickness in patients with type 2 diabetes mellitus without clinical retinopathy. J Ophthalmol. 2013;2013:767931. [crossref] [PubMed]
22.
Romero-Aroca P, Baget-Bernaldiz M, Pareja-Rios A, Lopez-Galvez M, Navarro-Gil R, Verges R. Diabetic macular oedema pathophysiology: Vasogenic versus inflammatory. Journal of Diabetes Research. 2016;2016:2156273. Doi: 10.1155/2016/2156273. [crossref]
23.
Ribeiro L, Pappuru R, Lobo C, Alves D, Cunha-Vaz J. Different phenotypes of mild nonproliferative diabetic retinopathy with different risks for development of macular oedema (C-TRACER Study). Ophthalmic Research. 2018;59(2):59-67. [crossref] [PubMed]

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%)

ETYMOLOGY: Author Origin

JCDR is now Monthly and more widely Indexed .
  • Emerging Sources Citation Index (Web of Science, thomsonreuters)
  • Index Copernicus ICV 2017: 134.54
  • Academic Search Complete Database
  • Directory of Open Access Journals (DOAJ)
  • Embase
  • EBSCOhost
  • Google Scholar
  • HINARI Access to Research in Health Programme
  • Indian Science Abstracts (ISA)
  • Journal seek Database
  • Google
  • Popline (reproductive health literature)
  • www.omnimedicalsearch.com