Assessment of Inner Retinal Layers and Choroidal Thickness in Type 1 Diabetes Mellitus: A Cross-Sectional Study

Reduced macular thickness and vascular density in abnormal glucose metabolism patients: A meta-analysis of optical coherence tomography (OCT) and OCT angiography studies

BACKGROUND

Alterations in macular thickness and vascular density before clinically visible diabetic retinopathy (DR) remain inconclusive. This study aimed to determine whether retinal manifestations in abnormal glucose metabolism (AGM) patients differ from those in the healthy individuals.

METHODS

PubMed, Embase, and Web of Science were searched between 2000 and 2021. The eligibility criteria were AGM patients without DR. Primary and secondary outcomes measured by optical coherence tomography (OCT) and OCT angiography (OCTA) were analyzed and expressed as standardized mean differences (SMDs) with 95% confidence intervals (CIs). A random-effects model was used in the data synthesis. The potential publication bias for the variables was evaluated using Egger's test.

RESULTS

A total of 86 observational studies involving 13,773 participants and 15,416 eyes were included. OCT revealed that compared to healthy controls, the total macular thickness of AGM patients was thinner, including the thickness of fovea (-0.24, 95% CI [-0.39, -0.08]; P  = 0.002, I2  = 87.7%), all regions of parafovea (-0.32, 95% CI [-0.54, -0.11]; P  = 0.003; I2  = 71.7%) and the four quadrants of perifovea; the thickness of peripapillary retinal nerve fiber layer (pRNFL), macular retinal nerve fiber layer (mRNFL), and ganglion cell layer (GCL) also decreased. OCTA indicated that the superficial and deep vascular density decreased, the foveal avascular zone (FAZ) area enlarged, and the acircularity index (AI) reduced in AGM individuals.

CONCLUSIONS

Retinal thinning and microvascular lesions have occurred before the advent of clinically detectable DR; OCT and OCTA may have the potential to detect these preclinical changes.

REGISTRATION

PROSPERO; http://www.crd.york.ac.uk/prospero/ ; No. CRD42021269885.

Current understanding of subclinical diabetic retinopathy informed by histology and high-resolution in vivo imaging

The escalating incidence of diabetes mellitus has amplified the global impact of diabetic retinopathy. There are known structural and functional changes in the diabetic retina that precede the fundus photography abnormalities which currently are used to diagnose clinical diabetic retinopathy. Understanding these subclinical alterations is important for effective disease management. Histology and high-resolution clinical imaging reveal that the entire neurovascular unit, comprised of retinal vasculature, neurons and glial cells, is affected in subclinical disease. Early functional manifestations are seen in the form of blood flow and electroretinography disturbances. Structurally, there are alterations in the cellular components of vasculature, glia and the neuronal network. On clinical imaging, changes to vessel density and thickness of neuronal layers are observed. How these subclinical disturbances interact and ultimately manifest as clinical disease remains elusive. However, this knowledge reveals potential early therapeutic targets and the need for imaging modalities that can detect subclinical changes in a clinical setting.

Early choroidal and retinal changes detected by swept-source oct in type 2 diabetes and their association with diabetic kidney disease: a longitudinal prospective study

BACKGROUND

To evaluate structural changes in retina and choroid in patients with type 2 diabetes (T2D) and their association with diabetic kidney disease (DKD).

METHODS

T2D patients with mild or no diabetic retinopathy (DR) were followed for 3 years using structural SS-OCT and OCT angiography (OCT-A) taken every 6 months. Parameters were compared longitudinally and according to the DKD status on baseline.

RESULTS

One hundred and sixty eyes from 80 patients were followed for 3 years, 72 with no DKD (nDKD) at baseline and 88 with DKD. Trend analysis of T2D showed significant thinning in GCL + and circumpapillary retinal fiber neural layer (cRFNL), choroid, and decreased vascular density (VD) in superficial plexus and central choriocapillaris with foveal avascular zone (FAZ) enlargement. Patients with no DKD on baseline presented more significant declines in retinal center and choroidal thickness, increased FAZ and loss of nasal and temporal choriocapillaris volume. In addition, the nDKD group had worse glycemic control and renal parameters at the end of the study.

CONCLUSION

Our data suggests the potential existence of early and progressive neurovascular damage in the retina and choroid of patients with Type 2 Diabetes (T2D) who have either no or mild Diabetic Retinopathy (DR). The progression of neurovascular damage appears to be correlated with parameters related to glycemic control and renal damage.

Identification of circular RNA-Dcaf6 as a therapeutic target for optic nerve crush-induced RGC degeneration

The death of retinal ganglion cells (RGCs) can cause irreversible injury in visual function. Clarifying the mechanism of RGC degeneration is critical for the development of therapeutic strategies. Circular RNAs (circRNAs) are important regulators in many biological and pathological processes. Herein, we performed circRNA microarrays to identify dysregulated circRNAs following optic nerve crush (ONC). The results showed that 221 circRNAs were differentially expressed between ONC retinas and normal retinas. Notably, the levels of circular RNA-Dcaf6 (cDcaf6) expression in aqueous humor of glaucoma patients were higher than that in cataract patients. cDcaf6 silencing could reduce oxidative stress-induced RGC apoptosis in vitro and alleviate retinal neurodegeneration in vivo as shown by increased neuronal nuclei antigen (NeuN, neuronal bodies) and beta-III-tubulin (TUBB3, neuronal filaments) staining and reduced glial fibrillary acidic protein (GFAP, activated glial cells) and vimentin (activated glial cells) staining. Collectively, this study identifies a promising target for treating retinal neurodegeneration.

Optical coherence tomography evaluation of choroidal structure changes in diabetic retinopathy patients: A systematic review and meta-analysis

Introduction

Diabetic retinopathy (DR) is one of the major causes of blindness among working-aged adults worldwide. This study aimed to evaluate the differences in the subfoveal choroidal thickness (SFCT) and choroidal vascularity index (CVI) using optical coherence tomography (OCT) of patients with diabetic eyes with no retinopathy (NDR) and with diabetic retinopathy (DR).

Methods

We performed a comprehensive literature search of the PubMed, Embase, and Cochrane Library databases up to October 2021. The weighted mean difference (WMD) with the 95% confidence interval (CI) was pooled for continuous outcomes.

Results

Twenty-three cross-sectional studies comprising 2,534 eyes including 1,070 NDR eyes, 1,464 DR eyes were included in the systematic review and meta-analysis. The pooled results showed SFCT was significantly thicker in DR than in NDR patients after adjusting for axial length (WMD = 27.90 μm; 95% CI: 11.51 to 44.28; P = 0.001), and the CVI was significantly lower in DR patients (WMD = −1.59; 95% CI: −2.67 to −0.52; P = 0.004).

Conclusion

We described changes in the SFCT and CVI in DR. Resultantly, the CVI and SFCT may be valuable parameters for monitoring the onset of DR and helpful for a better understanding of the role of the choroid in the pathological process of DR.

Systematic review registration

https://www.crd.york.ac.uk/prospero/#myprospero, CRD42021228738.

Ganglion cell complex and retinal nerve fiber layer thickness in gestational diabetes mellitus

PURPOSE

The purpose of this study was to compare ganglion cell complex and peripapillary retinal nerve fiber layer (RNFL) thickness between pregnant females with gestational diabetes mellitus (GDM) and healthy pregnant females.

MATERIALS AND METHODS

This was a single-center, prospective, analytical cross-sectional study including pregnant females with a gestational age of 24 weeks or more in the GDM and control groups. The GDM group included 162 pregnant females with GDM, and the control group included 162 healthy pregnant females. Peripapillary RNFL (pRNFL), macular RNFL (mRNFL), GCL+ (ganglion cell layer [GCL] + inner plexiform layer [IPL]), and GCL++ (mRNFL + GCL + IPL) thickness were analyzed using spectral-domain optical coherence tomography (OCT), and comparisons were made between the groups.

RESULTS

Both the groups had similar mean age (P = 0.219), intraocular pressure (P = 0.186), central corneal thickness (P = 0.689), Schirmer test value (P = 0.931), and tear breakup time (P = 0.651). The mean pRNFL thickness of the GDM and control groups was 100.75 ± 8.36 μm and 106.77 ± 8.44 μm (P < 0.0001). pRNFL was significantly thinner in all four quadrants (P < 0.05) in the GDM compared to the control group. We observed that the mean mRNFL, GCL+, and GCL++ thickness were significantly reduced in GDM in comparison to the control group (P < 0.05).

CONCLUSION

Our study showed that OCT plays an indispensable role in determining initial retinal changes caused by GDM before the development of diabetic retinopathy.

Predictive Value of the Advanced Lipoprotein Profile and Glycated Proteins on Diabetic Retinopathy

This study aimed to assess whether the advanced characteristics of serum lipoprotein subclasses could better predict the risk of developing diabetic retinopathy (DR) and its severity compared to other established risk factors in subjects with type 1 (T1D) and type 2 (T2D) diabetes. This observational, cross-sectional substudy analyzed DR-related data from 309 T1D and 264 T2D subjects. The advanced lipoprotein and glycoprotein profile was determined by nuclear magnetic resonance (NMR) spectroscopy (Liposcale test). NMR analysis of lipoproteins revealed that T1D subjects with DR showed standard non-HDL particles, despite higher IDL lipid concentrations. Notably, IDL lipids were elevated in T1D subjects with worsened DR. VLDL and LDL were smaller, whereas HDL triglycerides were increased in DR compared with non-DR. On the other hand, the T2D subjects with DR showed altered characteristics in the LDL fraction, mainly revealed by a significant decrease in smaller LDL and a reduction in LDL-C. Moreover, the glycoprotein profile did not reveal significant changes among DR groups, regardless of the type of diabetes. However, lipoprotein characteristics and glycoproteins unveiled by NMR analysis did not improve the predictive value of conventional lipids or other traditional, well-established biomarkers of DR in our cohorts.

Markers of the sympathetic, parasympathetic and sensory nervous system are altered in the human diabetic choroid

BACKGROUND

We sought to evaluate alterations in markers of the autonomic nervous system in human diabetic choroid.

METHODS

Eighteen eyeballs from subjects with diabetes and 22 eyeballs from subjects without diabetes were evaluated in this study. Synaptophysin, tyrosine hydroxylase (TH), dopamine beta-hydroxylase (DβH), neuronal nitric oxide synthase (nNOS), choline acetyltransferase (ChAT), vesicular monoamine transporter II (VMAT-2), vesicular acetylcholine transporter (VAChT), vasoactive intestinal peptide (VIP), neuropeptide Y (NPY), and calcitonin gene-related peptide (CGRP) levels were detected by western blot analysis and immunofluorescence was performed in some cases. Furthermore, differences in adrenergic (α1- and β2-subtypes) and cholinergic (M1 and M3) receptor levels between diabetic subjects and controls were noted.

RESULTS

Decreased synaptophysin levels were found in diabetic choroids by western blot analysis and a reduction of synaptophysin-immunoreactive nerves was also found by immunofluorescence. Furthermore, a decrease of the levels of the key enzyme (TH) and transporter (VMAT2) of norepinephrine was evident both by western blot analysis and immunofluorescence. Additionally, increased NPY, VAChT, nNOS, and CGRP levels were observed in diabetic choroids. The levels of adrenergic (β2 subtype) and acetylcholine (M1 subtype) receptors decreased in diabetic choroids, as shown by western blotting and although the differences in α1 and M3 were not significant, there was a downward trend.

CONCLUSIONS

In the diabetic choroid, the levels of neurotransmitters, enzymes, and receptors associated with choroidal blood flow regulation are altered. These changes may affect the regulation of choroidal blood flow and may be associated with impaired retinal function and retinal pathology.

Evaluation of an Intravitreal Rho-Associated Kinase Inhibitor Depot Formulation in a Rat Model of Diabetic Retinopathy

Rho-associated kinase (ROCK) activation was shown to contribute to microvascular closure, retinal hypoxia, and to retinal pigment epithelium (RPE) barrier disruption in a rat model of diabetic retinopathy. Fasudil, a clinically approved ROCK inhibitor, improved retinal perfusion and reduced edema in this model, indicating that ROCK inhibition could be a promising new therapeutic approach for the treatment of diabetic retinopathy. However, due to its short intravitreal half-life, fasudil is not suitable for long-term treatment. In this study, we evaluated a very potent ROCK1/2 inhibitor (BIRKI) in a depot formulation administered as a single intravitreal injection providing a slow release for at least four weeks. Following BIRKI intravitreal injection in old Goto-Kakizaki (GK) type 2 diabetic rats, we observed a significant reduction in ROCK1 activity in the retinal pigment epithelium/choroid complex after 8 days and relocation of ROCK1 to the cytoplasm and nucleus in retinal pigment epithelium cells after 28 days. The chronic ROCK inhibition by the BIRKI depot formulation restored retinal pigment epithelial cell morphology and distribution, favored retinal capillaries dilation, and reduced hypoxia and inner blood barrier leakage observed in the diabetic retina. No functional or morphological negative effects were observed, indicating suitable tolerability of BIRKI after intravitreous injection. In conclusion, our data suggest that sustained ROCK inhibition, provided by BIRKI slow-release formulation, could be a valuable treatment option for diabetic retinopathy, especially with regard to the improvement of retinal vascular infusion and protection of the outer retinal barrier.

Choroidal vascular structures in diabetic patients: a meta-analysis

PURPOSE

Choroidal vascular structures are likely to be affected in diabetic patients. The aim of this study was to conduct a meta-analysis of choroidal vascular structures in diabetic eyes with no diabetic retinopathy (NDR) and healthy control eyes, which was systematically evaluated by various factors involving the measurements.

METHODS

This study identified clinical data from publications in PubMed and web of science until May 2020. Independent retrospective or prospective clinical studies comparing NDR and healthy control eyes regarding choroidal vascular structures were extracted. Five related studies were enrolled, cumulating in a total of 282 diabetic eyes and 511 control eyes examined in this study. Heterogeneity was statistically quantified by I2 statistics, and meta-analysis was performed using a random effects model. This study included 2 different algorisms of binarization determining the ratio of luminal areas in total choroidal areas, both of which were consolidated and called "choroidal vascular ratio."

RESULTS

Meta-analysis clearly showed that the choroidal vascular ratio was significantly lower in NDR eyes than in healthy control eyes (weighted mean difference =  - 2.16; 95%CI: - 3.19 to - 1.13; P < 0.005). Similar results were obtained in sub-analysis based on adjustment of serum HbA1c levels and duration of diabetes.

CONCLUSIONS

The choroidal vascular ratio of NDR eyes was significantly lower than that of healthy control eyes. The ratio might contribute to a better understanding of the pathophysiology involved in the development of diabetic retinopathy, although there was some heterogeneity in primary analysis studies.

The Role of MicroRNAs in Mitochondria-Mediated Eye Diseases

The retina is among the most metabolically active tissues with high-energy demands. The peculiar distribution of mitochondria in cells of retinal layers is necessary to assure the appropriate energy supply for the transmission of the light signal. Photoreceptor cells (PRs), retinal pigment epithelium (RPE), and retinal ganglion cells (RGCs) present a great concentration of mitochondria, which makes them particularly sensitive to mitochondrial dysfunction. To date, visual loss has been extensively correlated to defective mitochondrial functions. Many mitochondrial diseases (MDs) show indeed neuro-ophthalmic manifestations, including retinal and optic nerve phenotypes. Moreover, abnormal mitochondrial functions are frequently found in the most common retinal pathologies, i.e., glaucoma, age-related macular degeneration (AMD), and diabetic retinopathy (DR), that share clinical similarities with the hereditary primary MDs. MicroRNAs (miRNAs) are established as key regulators of several developmental, physiological, and pathological processes. Dysregulated miRNA expression profiles in retinal degeneration models and in patients underline the potentiality of miRNA modulation as a possible gene/mutation-independent strategy in retinal diseases and highlight their promising role as disease predictive or prognostic biomarkers. In this review, we will summarize the current knowledge about the participation of miRNAs in both rare and common mitochondria-mediated eye diseases. Definitely, given the involvement of miRNAs in retina pathologies and therapy as well as their use as molecular biomarkers, they represent a determining target for clinical applications.

Evaluation of choroidal thickness in children with type 1 diabetes: the role of optical coherence tomography in diabetic retinopathy screening

The present study aimed to evaluate choroidal changes and alternations within the structure of the retina prior to visible morphologic signs of diabetic retinopathy (DR) in pediatric type 1 diabetes (T1D) cases. Two hundred and six eyes of 103 pediatric patients with T1D without DR and 88 eyes of 44 healthy controls were enrolled. They underwent a comprehensive ophthalmic examination and optical coherence tomography evaluation. Choroidal thickness (ChT) measurements were performed manually on macular and peripapillary regions. There was no significant difference between the two groups in terms of age, intraocular pressure, and axial length (p > 0.05). ChT measurements of subfoveal, nasal, and temporal macula were slightly thinner in the diabetic group, and no statistical significance was found (p = 0.835, p = 0.305, and p = 0.054, respectively). Peripapillary ChT of eight sectors were also thinner in T1D; however, superonasal, nasal, inferonasal, and inferior sector values were significantly different (p = 0.010, p = 0.020, p = 0.019, and p = 0.018, respectively). In conclusion; this study demonstrated evidence of peripapillary choroidal thinning in pediatric diabetic patients without visible signs of retinopathy.

Analysis of retinal neurodegeneration in gestational and type 2 diabetes using swept-source optical coherence tomography

OBJECTIVE

This study aimed to compare the retina and choroid thickness in age-matched pregnant individuals with gestational diabetes mellitus, nonpregnant diabetic females, and healthy nonpregnant females.

METHOD

This cross-sectional study included 2 study groups, 1 composed of pregnant women with gestational diabetes mellitus and 1 consisting of nonpregnant type 2 diabetic patients without diabetic retinopathy, and a control group of healthy nonpregnant subjects. Swept-source optical coherence tomography was used to measure the retinal and choroidal thickness. The measurements were compared between the study groups and between the study groups and the control group.

RESULTS

All groups had similar mean ages, best-corrected visual acuity, and intraocular pressure (p = 0.122, p = 0.158, and p = 0.186, respectively). The mean central macular thickness of the gestational diabetes, type 2 diabetes, and control groups was 215.3 ± 10.83, 220.58 ± 21.62, and 230.03 ± 21.24 μm, respectively (p = 0.002). The retinal nerve fibre layer was slightly thinner only in the inferior zone of the study groups (p = 0.058) compared with the control group. We observed statistically significant differences in the thickness of all sectors of the ganglion cell layer between all groups (all p < 0.05), with the nonpregnant type 2 diabetic group exhibiting the lowest values. A similar mean subfoveal choroidal thickness was observed in all 3 groups (p = 0.247).

CONCLUSION

Swept-source optical coherence tomography plays an important role in detecting retinal neurodegenerative changes and choroidal thickness induced by gestational and type 2 diabetes before the development of diabetic retinopathy.

Choroidal Thickness in Diabetic Patients Without Diabetic Retinopathy: A Meta-analysis

PURPOSE

To evaluate the relationship between diabetic eyes without diabetic retinopathy and healthy eyes in subfoveal choroidal thickness.

DESIGN

Systematic review and meta-analysis.

METHODS

An independent retrospective or prospective clinical study comparing diabetic eyes without diabetic retinopathy and healthy control eyes in the subfoveal choroidal thickness was selected. This study compiled data from publications in PubMed and Web of Science between January 1, 2008, and November 15, 2019. Heterogeneity was statistically quantified by I2 statistics, and meta-analysis was performed using a random-effects model.

RESULTS

Seventeen related studies were identified, including a total of 4,213 eyes, which consisted of 1,197 diabetic eyes without diabetic retinopathy and 3,016 healthy eyes. Meta-analysis clearly showed that the subfoveal choroidal thickness of diabetic eyes without retinopathy was significantly thinner than that of healthy control eyes (weighted mean difference = -14.34 μm; 95% confidence interval: -24.37 to -4.32 μm; P < .005). Similar results were obtained in sub-analysis based on the adjustment of the axial length.

CONCLUSIONS

This study suggests that the subfoveal choroidal thickness was thin in diabetic eyes without retinopathy compared to healthy eyes. Subfoveal choroidal thickness might be an important parameter for the development of diabetic retinopathy in diabetic eyes without retinopathy.

Inflammatory cells proliferate in the choroid and retina without choroidal thickness change in early Type 1 diabetes

Increasing evidence points to inflammation as a key factor in the pathogenesis of diabetic retinopathy (DR). Choroidal inflammatory changes in diabetes have been reported and in vivo choroidal thickness (CT) has been searched as a marker of retinopathy with contradictory results. We aimed to investigate the early stages in the retina and choroid in an animal model of Type 1 diabetes. Type 1 diabetes was induced in male Wistar rats via a single i.p. streptozotocin injection. At 8 weeks after disease onset, CT, choroidal vascular density, VEGF and VEGFR2 expression, microglial cell and pericyte distribution were evaluated. Diabetic rats showed no significant change in CT and choroidal vascular density. A widened pericyte-free gap between the retinal pigment epithelium and the choroid was observed in diabetic rats. The immunoreactivity of VEGFR2 was decreased in the retina of diabetic rats, despite no statistically significant difference in the immunoreactivity of VEGF. The density of microglial cells significantly increased in the choroid and retina of diabetic rats. Reactive microglial cells were found to be more abundant in the choroid of diabetic rats. Evidences of the interconnection between the superficial, intermediate, and deep plexuses of the retina were also observed. At early stages, Type 1 diabetes does not affect choroidal thickness and choroidal vascular density. Proliferation and reactivity of microglial cells occurs in the choroidal stroma and the retina. The expression of VEGFR2 decreases in the retina.

Assessment of retinal neurodegeneration with spectral-domain optical coherence tomography: a systematic review and meta-analysis

OBJECTIVES

To comprehensively assess diabetic retinopathy neurodegeneration (DRN) as quantified by retinal neuronal and axonal layers measured with spectral-domain optical coherence tomography (SD-OCT) in subjects with diabetes mellitus (DM).

METHODS

Articles on the topic of examining macular ganglion cell-inner plexiform layer (m-GCIPL), macular retinal nerve fibre layer (m-RNFL), macular ganglion cell complex (m-GCC), and peripapillary RNFL (p-RNFL) measured with SD-OCT in DM subjects without DR (NDR) or with non-proliferative DR (NPDR) were searched in PubMed and Embase up to November 31, 2019. Standardized mean difference (SMD) as effect size were pooled using random-effects model.

RESULTS

Thirty-six studies searched from online databases and the CUHK DM cohort were included in the meta-analysis. In the comparison between NDR and control, macular measures including mean m-GCIPL (SMD = -0.26, p = 0.003), m-RNFL (SMD = -0.26, p = 0.046), and m-GCC (SMD = -0.28; p = 0.009) were significantly thinner in the NDR group. In the comparison between NPDR and NDR, only mean p-RNFL was significantly thinner in the NPDR group (SMD = -0.27; p = 0.03), but not other macular measures.

CONCLUSIONS

Thinning of retinal neuronal and axonal layers at macula as measured by SD-OCT are presented in eyes with NDR, supporting DRN may be the early pathogenesis in the DM patients without the presence of clinical signs of DR. In the future, these SD-OCT measures may be used as surrogates of DRN to stratify DM patients with a high risk of DR, and may be used as a therapeutic target if neuroprotection treatment for DR is available.

Can ocular changes be detected early in children and adolescents with type 1 diabetes mellitus without retinopathy by using optical biometry and optical coherence tomography?

PURPOSE

To determine early ocular changes in children and adolescents with type 1 diabetes mellitus without retinopathy (T1DM-woR) by optical biometry (OB) and optical coherence tomography (OCT).

METHODS

Seventy children and adolescents with T1DM-woR (patient group) and 72 healthy children and adolescents (control group) were included. Demographic data, anthropometric measurements and anterior-posterior segment parameters of groups were compared. Correlations between ocular parameters and glycosylated hemoglobin (HbA1c) level, age at diabetes mellitus (DM) onset and DM duration were evaluated.

RESULTS

Patients with T1DM-woR had significantly shallower anterior chambers (3.50 ± 0.12 vs 3.67 ± 0.11 mm, p < 0.001), thicker lenses (3.65 ± 0.15 vs 3.37 ± 0.14 mm, p < 0.001), thinner central retinal nerve fiber layer (RNFL) thicknesses (95.3 ± 6.7 vs 104.8 ± 6.2 µm, p < 0.001) and thinner central choroidal thicknesses (292.8 ± 23.6 vs 325.1 ± 24.7 µm, p < 0.001) than healthy individuals. As the lens thickness (LT) increased, anterior chamber depth (ACD) decreased in patient group (r = - 0.368, p = 0.040). Other anterior (central corneal thickness, axial length, keratometry, spherical equivalent) and posterior (superior temporal, superior nasal, nasal, inferior nasal, inferior temporal, temporal RNFL thicknesses; nasal and temporal choroidal thicknesses; central part's and inner-outer macular segments' thickness and volume measurements) segment parameters of groups were similar (p > 0.05). In patient group, as HbA1c level increased, central RNFL and choroidal thicknesses decreased (r = - 0.639, p < 0.001; r = - 0.486, p = 0.010, respectively).

CONCLUSIONS

In patients with T1DM, we found that LT increased, and ACD, central RNFL and choroidal thicknesses decreased by OB and OCT before visible findings appeared in routine ophthalmological examination. Determination of early changes is warning to physician and patient in order to prevent more serious damages occurring later.

Chronic Diabetes Complications: The Need to Move beyond Classical Concepts

Chronic-diabetes-related complications simultaneously compromise both the micro- and macrovascular trees, with target organs considered as the paradigm of large vessel injury also entailing microangiopathic changes. However, complications independent or partially independent from vascular damage are often overlooked. This includes neuronal dysfunction (e.g., retinal neurodegeneration), interstitial injury (e.g., tubulointerstitial disease), metabolic damage (e.g., in the heart and liver), and nonclassical conditions such as cognitive decline, impaired pulmonary function, or increased risk of cancer. In this scenario, researchers, endocrinologists and primary care physicians should have a holistic view of the disease and pay further attention to all organs and all potential clinical repercussions, which would certainly contribute to a more rational and integrated patient health care.