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Aim: To investigate the relationship between diabetic peripheral neuropathy (DPN) and retinal tissue thickness., Methods: Full retinal thickness in the central retinal, parafoveal, and perifoveal zones and thickness of the ganglion cell complex and retinal nerve fiber layer (RNFL) were assessed in 193 individuals (84 with type 1 diabetes, 67 with type 2 diabetes, and 42 healthy controls) using spectral domain optical coherence tomography. Among those with diabetes, 44 had neuropathy defined using a modified neuropathy disability score recorded on a 0-10 scale. Multiple regression analysis was performed to investigate the relationship between diabetic neuropathy and retinal tissue thickness, adjusted for the presence of diabetic retinopathy (DR), age, sex, duration of diabetes, and HbA 1c levels., Results: In individuals with diabetes, perifoveal thickness was inversely related to the severity of neuropathy (p < 0.05), when adjusted for age, sex, duration of diabetes, and HbA 1c levels. DR was associated with reduced thickness in parafovea (p < 0.01). The RNFL was thinner in individuals with greater degrees of neuropathy (p < 0.04)., Conclusions: DPN is associated with structural compromise involving several retinal layers. This compromise may represent a threat to visual integrity and therefore warrants examination of functional correlates.

Diabetic Peripheral Neuropathy (DPN) is one of the most common types of diabetes that can affect the cornea. An accurate analysis of the nerve structures can assist the early diagnosis of this disease. This paper proposes a robust, fast and fully automatic nerve segmentation and morphometric parameter quantification system for corneal confocal microscope images. The segmentation part consists of three main steps. First, a preprocessing step is applied to enhance the visibility of the nerves and remove noise using anisotropic diffusion filtering, specifically a Coherence filter followed by Gaussian filtering. Second, morphological operations are applied to remove unwanted objects in the input image such as epithelial cells and small nerve segments. Finally, an edge detection step is applied to detect all the nerves in the input image. In this step, an efficient algorithm for connecting discontinuous nerves is proposed. In the morphometric parameters quantification part, a number of features are extracted, including thickness, tortuosity and length of nerve, which may be used for the early diagnosis of diabetic polyneuropathy and when planning Laser-Assisted in situ Keratomileusis (LASIK) or Photorefractive keratectomy (PRK). The performance of the proposed segmentation system is evaluated against manually traced ground-truth images based on a database consisting of 498 corneal sub-basal nerve images (238 are normal and 260 are abnormal). In addition, the robustness and efficiency of the proposed system in extracting morphometric features with clinical utility was evaluated in 919 images taken from healthy subjects and diabetic patients with and without neuropathy. We demonstrate rapid (13 seconds/image), robust and effective automated corneal nerve quantification. The proposed system will be deployed as a useful clinical tool to support the expertise of ophthalmologists and save the clinician time in a busy clinical setting., (Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.)

To identify in a large population cohort the clinical and biochemical characteristics of patients with diabetes at risk of foot ulceration and outcomes in those with foot ulcers. All patients with diabetes attending Baqai Institute of Diabetology and Endocrinology from January 2004 to April 2012 included in the study. Clinical, biochemical and socio-demographic data were collected and patients were categorised into those at no risk of ulceration, at risk of ulceration and those with foot ulcer, according to the University of Texas classification. Patients with foot ulceration followed for their final outcome, that is complete healing, persisted non-healed ulcer, lower extremity amputation, lost to follow-up or death. A total of 18 119 patients with diabetes underwent assessment, 3576 (19·7%) patients defined as at high risk for foot ulceration and 3731 (20·6%) presented with foot ulcer. Age, male gender, hypertension, higher glycated haemoglobin (HbA1c), history of smoking and presence of neuropathy were risk factors (P < 0·000) for foot ulceration. Amputation rate in patients with foot ulceration was significantly related to severity of ulceration at presentation. Preventive foot care practices were followed by 19·02% patients. One thousand eight hundred seventy three (50·2%) patients completely healed, 293 (11%) patients underwent amputation and 397 (10·1%) patients continued to be treated in the foot clinic. All patients with diabetes should be screened for neuropathy to identify those at risk of foot ulceration, as it is the major contributory factor for foot ulceration. The final outcome of foot ulceration was determined by the severity and grade of ulcer at presentation., (© 2014 The Authors. International Wound Journal © 2014 Medicalhelplines.com Inc and John Wiley & Sons Ltd.)

Objective: We analysed the Qatar stroke registry for ethnic variations in patients admitted with cerebrovascular disease at Hamad General Hospital, Qatar., Methods: Patients admitted with acute stroke from January 2014 to December 2015, enrolled in the registry were included in the study. We evaluated the clinical presentation, risk factors, and outcome at discharge and 90 days post-discharge in relation to the patient's ethnic background., Results: A total of 1727 patients were enrolled in the Hamad General Hospital stroke registry (Middle Eastern 594 (34.4%), South East Asian 924 (53.5%) and Far Eastern 209 (12.1%)). There were significant differences in risk factors, clinical presentation and prognosis. Compared to Middle Eastern patients, Far Eastern patients were younger (62.8 ± 13.7 vs. 48.9 ± 9.1 years; p < 0.001). Diabetes and hypertension were significantly more common in Middle Eastern patients (358 (60.3%), 458 (77.1%)) compared to South East Asian patients (420 (45.5%), 596 (64.5%)) and Far Eastern patients (57 (27.3%), 154 (73.7%)), respectively (p < 0.001). Stroke was more severe in the Far Eastern group (median (interquartile range) - 5.0 (2-11.5)) compared to the Middle Eastern group (median (interquartile range) - 4.0 (1-8)) and South East Asian (median (interquartile range) - 4.0 (2-9)), p = 0.011. Mortality at 90 days was highest in patients from the Far East (15/209 (8.2%)) compared to the Middle East (35/594 (6.5%)) and South East Asia (33/924 (4.0)), p = 0.028. Patients from the Far East had significantly higher rates of intracranial hemorrhage compared to the Middle East and South East Asia (70/209 (33.5%), 77/594 (13.0%), and 169/924 (18.3%)), respectively (p < 0.001)., Conclusion: The early age at presentation and the poor control of risk factors, especially in patients from South East Asia and the Far East requires attention., Competing Interests: The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Diabetes mellitus is associated with a considerably increased risk of premature atherosclerotic cardiovascular disease. Intensive glycemic control has essentially failed to significantly improve cardiovascular outcomes in clinical trials. Dyslipidemia is common in diabetes and there is strong evidence that cholesterol lowering improves cardiovascular outcomes, even in patients with apparently unremarkable lipid profiles. Here, the authors review the pathophysiology and implications of the alterations in lipoproteins observed in both type 1 and type 2 diabetes, the effect of medications commonly used in the management of diabetes on the lipid profile, the evidence for lifestyle and pharmaceutical interventions, and national and international recommendations for the management of dyslipidemia in patients with diabetes.

Purpose: The aim of this study was to determine alterations to the corneal subbasal nerve plexus (SNP) over 4 years using in vivo corneal confocal microscopy in participants with type 1 diabetes and to identify significant risk factors associated with these alterations., Methods: A cohort of 108 individuals with type 1 diabetes and no evidence of peripheral neuropathy at enrollment underwent laser-scanning in vivo corneal confocal microscopy, ocular screening, and health and metabolic assessment at baseline, and the examinations continued for 4 subsequent annual visits. At each annual visit, 8 central corneal images of the SNP were selected and analyzed to quantify corneal nerve fiber density, corneal nerve branch density and corneal nerve fiber length. Linear mixed model approaches were fitted to examine the relationship between risk factors and corneal nerve parameters., Results: A total of 96 participants completed the final visit and 91 participants completed all visits. No significant relationships were found between corneal nerve parameters and time, sex, duration of diabetes, smoking, alcohol consumption, blood pressure, or body mass index. However, corneal nerve fiber density was negatively associated with glycated hemoglobin (β = -0.76, P < 0.01) and age (β = -0.13, P < 0.01) and positively related to high-density lipids (β = 2.01, P = 0.03). Higher glycated hemoglobin (β = -1.58, P = 0.04) and age (β = -0.23, P < 0.01) also negatively impacted corneal nerve branch density. Corneal nerve fiber length was only affected by higher age (β = -0.06, P < 0.01)., Conclusions: Glycemic control, high-density lipid, and age have significant effects on SNP structure. These findings highlight the importance of diabetic management to prevent corneal nerve damage and the capability of in vivo corneal confocal microscopy for monitoring subclinical alterations in the corneal SNP in diabetes.

Background: adhesive capsulitis (AC) results in progressive painful restriction in range of movement and can reduce function and quality of life. Whilst it has been associated with diabetes mellitus (DM), there is considerable variation in the reported prevalence of AC in the diabetic population. The aim of this study is to determine through meta-analysis the prevalence of AC in DM and examine whether it is influenced by type of DM or insulin therapy. We also aim to further establish the prevalence of DM in patients presenting with AC., Methods: we conducted a literature search for terms regarding AC and DM on Embase and Pubmed NCBI., Results: of 5411 articles identified, 18 were selected. Meta-analysis showed that patients with DM were 5 (95% CI 3.2-7.7) times more likely than controls to have AC. The overall prevalence of AC in DM was estimated at 13.4% (95% CI 10.2-17.2%). Comparison of prevalence in patients on insulin vs other treatments showed no significant difference between the two. Meta-analysis estimated the prevalence of DM in AC at 30% (95% CI 24-37%)., Conclusion: to our knowledge this is the first meta-analysis to estimate the overall prevalence of diabetes in a population with AC. A high prevalence of AC exists in DM and equally a high prevalence of DM is present in AC. Screening for DM should be considered in patients presenting with AC.

Purpose: We have developed a novel technique to measure in vivo corneal nerve migration., Methods: Wide-field montages of the subbasal corneal nerve plexus were generated at baseline and after 3 weeks. The 2 montages were manually examined side by side to identify a referent landmark in the inferior whorl region and 20 additional nerve landmarks throughout each montage. A software program was developed to measure nerve migration by quantifying the movement of the nerve landmarks relative to the inferior whorl landmark over the 3-week period. To illustrate the utility of this technique, nerve migration was measured in 2 individuals with diabetes (one with and the other without neuropathy) and a healthy control participant., Results: The average nerve migration rate was calculated to be 18.4, 49.9, and 41.5 μm/wk for the diabetic individuals with and without neuropathy and the control participant, respectively. The number of landmarks for tracking nerve migration in the participants was 26, 21, and 20, and they were at an average distance of 1500, 1940, and 1461 μm, from the whorl, respectively. The rate of migration depended on the distance from the whorl; hence, linear equations were generated for each subject for comparison., Conclusions: This novel imaging technique allows rapid measurement of in vivo corneal nerve migration. The results indicate that diabetic neuropathy may be associated with reduced nerve migration; however, because of the high level of manual input required in this technique and the apparent complex characteristics of corneal nerve migration, repeatability and characterization studies are needed.

Background: Ten percent of elective surgical patients have diabetes. These patients demonstrate excess perioperative morbidity and mortality. National guidance on the management of adults with diabetes undergoing surgery was published in 2011. We present a region-wide audit of adherence to this guidance across the North Western Deanery., Methods: Local teams prospectively collected data according to a locally approved protocol. Pregnant, paediatric and non-elective patients were excluded from this audit. Patient characteristics, type of surgery and aspects of perioperative management were collated and centrally analysed against audit criteria based upon national recommendations., Results: 247 patients with diabetes were identified. HbA1c was recorded in 71% of patients preoperatively; 9% of patients with an abnormal HbA1c were not known by, or referred to, the diabetes team. 17% of patients were admitted the evening preceding surgery. The mean fasting time was 12:20(4) h. Variable rate i.v. insulin infusions (VRIII) were not used when indicated in 11%. Only 8% of patients received the recommended substrate fluid, along with the VRIII (5% glucose in 0.45% saline). Intra-operative capillary blood glucose (CBG) was measured hourly in 56% of patients. Intra-operative CBG was within the acceptable range (4-12 mmol.L(-1)) in 85% of patients. 73% of patients had a CBG measurement performed in recovery. The WHO checklist was used in 95% of patients., Conclusions: National perioperative guidelines were not adhered to in a substantial proportion of patients with diabetes undergoing elective surgery. This study represents a template for future trainee networks., (© The Author 2016. Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Background: Parenterally administered steroids have been shown to affect the metabolism of glucose and to cause abnormal blood glucose levels in diabetic patients. These abnormal blood glucose levels in diabetic patients raise concerns that intra-articular steroid injections also may affect blood glucose levels. We performed a systematic review of studies examining the effect of intra-articular steroid injections on blood glucose levels in patients with diabetes mellitus., Methods: A literature search of the PubMed, EMBASE, AMED, and CINAHL databases using all relevant keywords and phrases revealed 532 manuscripts. After the application of inclusion criteria, seven studies with a total of seventy-two patients were analyzed., Results: All studies showed a rise in blood glucose levels following intra-articular steroid injection. Four of the seven studies showed a substantial increase in blood glucose. Peak values reached as high as 500 mg/dL. The peak increase in blood glucose did not occur immediately following intra-articular steroid injection, and in some cases it took several days to occur. In many patients, post-injection hyperglycemia occurred within twenty-four to seventy-two hours., Conclusion: Intra-articular steroid injections may cause hyperglycemia in patients with diabetes mellitus, and patients should be warned of this complication. Diabetic patients should be advised to regularly monitor their blood glucose levels for up to a week after injection and should seek medical advice if safe thresholds are breached., Level of Evidence: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Purpose: The aim of this study was to quantify epithelial, stromal, and endothelial cell density, and subbasal nerve morphology in young patients with type 1 diabetes mellitus with and without diabetic retinopathy., Methods: A total of 28 young patients (mean age, 22.86 ± 9.05 years) with type 1 diabetes, with (n = 18) and without (n = 10) retinopathy, and 17 age-matched healthy control subjects (mean age, 26.53 ± 2.43 years) underwent corneal confocal microscopy (CCM)., Results: We found significantly lower epithelial (P < 0.0001) and endothelial (P = 0.001) cell densities and higher keratocyte cell density (P = 0.024) in patients with type 1 diabetes compared to controls. Significantly lower corneal nerve fiber density (P = 0.004), nerve branch density (P = 0.004), total nerve branch density (P = 0.04), and nerve fiber length (P = 0.001), and greater nerve fiber width (P = 0.04) were observed in patients with type 1 diabetes compared to control subjects. Significantly lower epithelial (P < 0.001) and endothelial (P = 0.02) cell densities, nerve branch density (P = 0.02), and nerve fiber length (P = 0.04), and significantly higher keratocyte cell density (P = 0.02) were found in patients with type 1 diabetes without retinopathy compared to control subjects., Conclusions: Corneal confocal microscopy identifies corneal cellular and small nerve fiber pathology in young patients with type 1 diabetes without retinopathy, which increases in severity in those with retinopathy. Corneal confocal microscopy appears to have considerable use as an imaging biomarker for early subclinical pathology in young patients with type 1 diabetes mellitus.

Objective: Muscle weakness and atrophy of the lower limbs may develop in patients with diabetes, increasing their risk of falls. The underlying basis of these abnormalities has not been fully explained. The aim of this study was to objectively quantify muscle strength and size in patients with type 2 diabetes mellitus (T2DM) in relation to the severity of neuropathy, intramuscular noncontractile tissue (IMNCT), and vitamin D deficiency., Research Design and Methods: Twenty patients with T2DM and 20 healthy control subjects were matched by age, sex, and BMI. Strength and size of knee extensor, flexor, and ankle plantar and dorsiflexor muscles were assessed in relation to the severity of diabetic sensorimotor polyneuropathy (DSPN), amount of IMNCT, and serum 25-hydroxyvitamin D (25OHD) levels., Results: Compared with control subjects, patients with T2DM had significantly reduced knee extensor strength (P = 0.003) and reduced muscle volume of both knee extensors (P = 0.045) and flexors (P = 0.019). Ankle plantar flexor strength was also significantly reduced (P = 0.001) but without a reduction in ankle plantar flexor (P = 0.23) and dorsiflexor (P = 0.45) muscle volumes. IMNCT was significantly increased in the ankle plantar (P = 0.006) and dorsiflexors (P = 0.005). Patients with DSPN had significantly less knee extensor strength than those without (P = 0.02) but showed no difference in knee extensor volume (P = 0.38) and ankle plantar flexor strength (P = 0.21) or volume (P = 0.96). In patients with <25 nmol/L versus >25 nmol/L 25OHD, no significant differences were found for knee extensor strength and volume (P = 0.32 vs. 0.18) and ankle plantar flexors (P = 0.58 vs. 0.12)., Conclusions: Patients with T2DM have a significant reduction in proximal and distal leg muscle strength and a proximal but not distal reduction in muscle volume possibly due to greater intramuscular fat accumulation in distal muscles. Proximal but not distal muscle strength is related to the severity of peripheral neuropathy but not IMNCT or 25OHD level., (© 2016 by the American Diabetes Association. Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered.)

Aims: Sensory neuropathy is central to the development of painful neuropathy, and foot ulceration in patients with diabetes. Currently, available QST devices take considerable time to perform and are expensive. NerveCheck is the first inexpensive ($500), portable QST device to perform both vibration and thermal testing and hence evaluate diabetic peripheral neuropathy (DPN). This study was undertaken to establish the reproducibility and diagnostic validity of NerveCheck for detecting neuropathy., Methods: 130 subjects (28 with DPN, 46 without DPN and 56 control subjects) underwent QST assessment with NerveCheck; vibration perception and thermal testing. DPN was defined according to the Toronto criteria., Results: NerveCheck's intra correlation coefficient for vibration, cold and warm sensation testing was 0.79 (95% LOA: -4.20 to 6.60), 0.86 (95% LOA: -1.38 to 2.72) and 0.71 (95% LOA: -2.36 to 3.83), respectively. The diagnostic accuracy (AUC) for vibration, cold and warm sensation testing was 86% (SE: 0.038, 95% CI 0.79-0.94), 79% (SE: 0.058, 95% CI 0.68-0.91) and 72% (SE: 0.058, 95% CI 0.60-0.83), respectively., Conclusions: This study shows that NerveCheck has good reproducibility and comparable diagnostic accuracy to established QST equipment for the diagnosis of DPN., Competing Interests: We wish to draw the attention of the Editor to the following facts which may be considered as potential conflicts of interest and to financial contributions to this work. Phi Med Europe S.L. provided the Nervecheck device, funded half of the study and covered some of the travel expenses and conference registration fees for presenting the results of this study. M.N. Odriozola, S. Odriozola, M.B. Odriozola and A. Odriozola are the owners and inventors of the NerveCheck. We confirm that the manuscript has been read and approved by all named authors and that there are no other persons who satisfied the criteria for authorship but are not listed. We further confirm that the order of authors listed in the manuscript has been approved by all of us., (Copyright © 2016 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.)

Purpose: To examine the retinal thickness profiles of individuals with and without diabetic retinopathy (DR)., Methods: Full retinal thickness in the central zone, overall and hemisphere thicknesses of the parafovea and perifovea, ganglion cell complex (GCC) thickness and retinal nerve fibre layer (RNFL) thickness were assessed in 185 individuals using spectral domain optical coherence tomography (88 individuals with diabetes but no DR, 55 with DR, and 42 non-diabetic controls). The DR group comprised of 60% of participants with very mild non-proliferative diabetic retinopathy (NPDR) (representing microaneurysms only) and 40% with mild NPDR (hard exudates, cotton-wool spots, and/or mild retinal haemorrhages). Regression analysis was performed to determine the factors associated with retinal tissue thickness, taking into account, age, sex, presence of DR, duration of diabetes, HbA1c levels and type of diabetes., Results: The mean (S.D.) of the overall parafoveal thickness was 306 (16) in the DR group and 314 (14) in the control group (p = 0.02). The mean (S.D.) of the superior hemisphere parafoveal thickness was 309 (16) in the DR group and 318 (14) in the control group (p = 0.02). The mean (S.D.) of the inferior hemisphere parafoveal thickness was 303 (17) in the DR group and 311 (15) in the control group (p = 0.02). There were no significant differences in retinal thickness between groups in the central zone (p = 0.27) or perifovea (p > 0.41). Neither the overall nor the hemisphere RNFL (p > 0.75) and GCC thickness (p > 0.37) were significantly different between the groups. Regression analysis revealed that parafoveal thickness in diabetic individuals was reduced in association with presence of DR (B = -5.9 μm, p = 0.02) and with advancing age (B = -4.5 μm, p = 0.004, for every 10 year increase in age) when adjusted for sex, duration of diabetes, HbA1c levels and type of diabetes., Conclusion: The inner macula is thinner in the presence of clinical signs of diabetic retinopathy and is compounded by advancing age. The influence of any macular oedema or that by cotton-wool spots could not be ruled out and may still confound these results., (© 2015 The Authors Ophthalmic & Physiological Optics © 2015 The College of Optometrists.)

Vitamin D deficiency is now recognized as a condition of increasing prevalence worldwide. Vitamin D has an established role in calcium and bone metabolism; however, more recently associations with vitamin D deficiency and risk of developing diabetes, diabetes complications, and cardiovascular disease have all been acknowledged. The vitamin D receptor is ubiquitously expressed, and experimental, in vitro, and in vivo studies strongly suggest a role in regulating the transcription of multiple genes beyond calcium homeostasis. These include antiproliferative, immunomodulatory, angiogenic, inhibition of the renin-angiotensin-aldosterone system, and neurotrophic factor expression. Observational studies report a strong association between vitamin D deficiency and cardiovascular and metabolic disorders; however, there remains a paucity of large long-term randomized clinical trials showing a benefit with treatment. An increasing body of literature suggests a possible pathogenetic role of vitamin D in the long-term complications of diabetes and vitamin D deficiency may also exacerbate symptoms of painful diabetic peripheral neuropathy. It remains unknown if supplementation of vitamin D to normal or non-deficient levels alters pathogenetic processes related to diabetic microvascular complications. With the high prevalence of vitamin D deficiency in patients with diabetes and putative mechanisms linking vitamin D deficiency to diabetic complications, there is a compelling argument for undertaking large well-designed randomized controlled trials of vitamin D supplementation.

Objective: To assess the effect of high-dose vitamin D in patients with painful diabetic neuropathy., Methods: A single intramuscular dose of 600 000 IU vitamin D was administered, and the effects on metabolic parameters and neuropathic pain assessed over 20 weeks., Results: 143 participants with predominantly type 2 diabetes, aged 52.31±11.48 years, with a Douleur Neuropathique 4 (DN4) score (3.0±1.8), total McGill pain score (21.2±14.9), and Short Form McGill Pain Questionnaire (SFMPQ) score (2.1±0.9), were enrolled. The baseline 25-hydroxyvitamin D (25(OH)D) level was 31.7±23.3 ng/mL and 58 (40.5%) patients showed evidence of vitamin D deficiency (25(OH)D<20 ng/mL). Intramuscular administration of vitamin D resulted in a significant increase in 25(OH)D (46.2±10.2 ng/mL, p<0.0001) and a reduction in positive symptoms on the DN4 (p<0.0001), total pain score (p<0.0001), and SFMPQ (p<0.0001)., Conclusions: Treatment with a single intramuscular dose of 600 000 IU of vitamin D in patients with painful diabetic neuropathy is associated with a significant decrease in the symptoms of painful diabetic neuropathy., Trial Registration Number: BIDE-12/2014.

Epigenetic marks critically control gene expression and thus the cellular activity state. The functions of many epigenetic modifiers in the vascular system have not yet been studied. We screened for histone modifiers in endothelial cells and observed a fairly high expression of the histone plant homeodomain finger protein 8 (PHF8). Given its high expression, we hypothesize that this histone demethylase is important for endothelial cell function. Overexpression of PHF8 catalyzed the removal of methyl-groups from histone 3 lysine 9 (H3K9) and H4K20, whereas knockdown of the enzyme increased H3K9 methylation. Knockdown of PHF8 by RNAi also attenuated endothelial proliferation and survival. As a functional readout endothelial migration and tube formation was studied. PHF8 siRNA attenuated the capacity for migration and developing of capillary-like structures. Given the impact of PHF8 on cell cycle genes, endothelial E2F transcription factors were screened, which led to the identification of the gene repressor E2F4 to be controlled by PHF8. Importantly, PHF8 maintains E2F4 but not E2F1 expression in endothelial cells. Consistently, chromatin immunoprecipitation revealed that PHF8 reduces the H3K9me2 level at the E2F4 transcriptional start site, demonstrating a direct function of PHF8 in endothelial E2F4 gene regulation. Conclusion: PHF8 by controlling E2F4 expression maintains endothelial function.

Background: Experimental and clinical studies suggest a possible association between vitamin D deficiency and both diabetic retinopathy and maculopathy., Methods: We have performed a cross-sectional study in adults with types 1 and 2 diabetes mellitus. The relationship between the presence and severity of diabetic retinopathy and maculopathy with serum 25-hydroxyvitamin D concentration was evaluated using logistic regression analyses in the presence of demographic and clinical covariates., Results: 657 adults with diabetes were stratified based on retinopathy grading: No Diabetic Retinopathy (39%), Background Diabetic Retinopathy (37%), Preproliferative Diabetic Retinopathy (21%), and Proliferative Diabetic Retinopathy (3%), respectively. There were no differences in serum 25-hydroxyvitamin D concentrations (25(OH)D) between the groups (15.3 ± 9.0 versus 16.4 ± 10.5 versus 15.9 ± 10.4 versus 15.7 ± 8.5 ng/mL, P = NS). Logistic regression analysis demonstrated no statistically significant relationship between the severity of retinopathy and serum 25(OH)D. Furthermore, there was no difference in serum 25(OH)D between those with (n = 94, 14%) and those without (n = 563, 86%) Diabetic Maculopathy (16.2 ± 10.0 versus 15.8 ± 9.8, P = NS) and no relationship was demonstrated by logistic regression analyses between the two variables., Conclusions: This study has found no association between serum 25(OH)D and the presence and severity of diabetic retinopathy or maculopathy.

Background: The objective was to investigate full retinal and inner retinal thickness in individuals with type 1 and type 2 diabetes., Methods: Eighty-four individuals with type 1 diabetes (T1DM), 67 individuals with type 2 diabetes (T2DM) and 42 non-diabetic individuals (control group) were enrolled. Participants underwent full retinal thickness evaluation in the central retinal, parafoveal and perifoveal zones and in the retinal nerve fibre layer (RNFL) and ganglion cell complex (GCC), using spectral domain optical coherence tomography. As a preliminary step, the key variables of interest - age, sex, diabetic retinopathy (DR), duration of diabetes and HbA1c levels - were analysed and compared between the three groups. Full retinal thickness, RNFL and GCC thicknesses were also compared between the groups. The relationship between the type of diabetes and retinal tissue thickness was explored, adjusting for the five potential confounders., Results: Compared to individuals with T1DM, individuals with T2DM had significantly reduced full retinal thickness in the parafovea and perifovea and reduced RNFL and GCC thickness. The mean differences were six (p = 0.020), seven (p = 0.008), six (p = 0.021) and four micrometres (p = 0.013) for the parafovea, perifovea, RNFL and GCC thicknesses, respectively. Thicknesses within the central zone (p = 0.018) and at the parafovea (p = 0.007) were significantly reduced in T2DM when compared to the control group. After adjusting for age, sex, diabetic retinopathy, duration of diabetes and HbA1c levels, the relationship between type of diabetes and retinal tissue thickness was not statistically significant (p > 0.056)., Conclusion: Retinal tissue thickness is not significantly different between type 1 and type 2 diabetes, when adjusted for age, sex, diabetic retinopathy, duration of diabetes and HbA1c levels., (© 2016 Optometry Australia.)

As of March 2016, we continue to advocate the diagnosis of diabetic neuropathy using a simple foot examination or monofilament, which identifies only those with severe neuropathy and hence risk of foot ulceration. Given the fact that the 5-year mortality rate of diabetic patients with foot ulceration is worse than that of most common cancers, surely we should be identifying patients at an earlier stage of neuropathy to prevent its progression to a stage with such a high mortality? Of course, we lament that there is no licensed treatment for diabetic neuropathy. Who is to blame? As researchers and carers, we have a duty of care to our patients with diabetic neuropathy. So, we have to look forward not backwards, and move away from our firmly entrenched views on the design and conduct of clinical trials for diabetic neuropathy. Relevant organizations such as Neurodiab, the American Diabetes Association and the Peripheral Nerve Society have to acknowledge that they cannot continue to endorse a bankrupt strategy. The FDA needs an open and self-critical dialogue with these organizations, to give pharmaceutical companies at least a fighting chance to deliver effective new therapies for diabetic neuropathy., (© 2016 Elsevier Inc. All rights reserved.)

Objective: There is an unmet need for better diagnostic tools to further delineate clinical subsets of heterogeneous chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) and multifocal motor neuropathy (MMN) to facilitate treatment decisions. Corneal confocal microscopy (CCM) is a noninvasive and reproducible nerve imaging technique. This study evaluates the potential of CCM as a diagnostic surrogate in CIDP and MMN., Methods: In a cross-sectional prospective approach, 182 patients and healthy controls were studied using CCM to quantify corneal nerve damage and immune cell infiltration., Results: Patients with CIDP and MMN had a reduction in corneal nerve fiber (CNF) measures and an increase in corneal immune cell infiltrates. In CIDP, CNF parameters decreased with increasing duration of disease. The number of dendritic cells in proximity to CNFs was increased in patients with early disease and correlated with the degree of motor affection. A further reduction in CNF parameters and an increase in nondendritic cells were observed in patients with painful neuropathy. In CIDP patients with antineuronal antibodies the number of nondendritic cells was increased., Interpretation: Our findings suggest that CNF loss may reflect severity of neuropathy and quantification of distinct cells around the CNF plexus may help in stratifying CIDP subtypes, clinical course, and disease activity. However, further longitudinal studies are required before CCM can be considered as a valid surrogate endpoint for patients with CIDP and MMN.

The rise in the global burden of diabetes is spurring an increase in the prevalence of its complications. Diabetic peripheral neuropathy (DPN) is a common and devastating complication of diabetes, with multiple clinical manifestations. The most common is a symmetrical length-dependent dysfunction and damage of peripheral nerves. The management of DPN rests on three tenets: intensive glycaemic control, even though the evidence of benefit is questionable in people with type 2 diabetes; pathogenetic therapies; and symptomatic treatment. A number of pathogenetic treatments have been evaluated in phase III clinical trials, including α-lipoic acid (stems reactive oxygen species formation), benfotiamine (prevents vascular damage) and aldose-reductase inhibitors (reduce flux through the polyol pathway), protein kinase C inhibitors (prevent hyperglycaemia-induced activation of protein kinase C), nerve growth factors (stimulate nerve regeneration) and Actovegin® (improves tissue glucose and oxygen uptake). However, none have gained US Food and Drug Administration or European Medicines Agency (EMA) approval, questioning the validity of current trial designs and the endpoints deployed to define efficacy. For painful diabetic neuropathy, clinical guidelines recommend: atypical analgesics for pain relief, including duloxetine and amitriptyline; the γ-aminobutyric acid analogues gabapentin and pregabalin; opioids, including Tapentadol; and topical agents such as lidocaine and capsaicin. No single effective treatment exists for painful DPN, highlighting a growing need for studies to evaluate more potent and targeted drugs, as well as combinations. A number of novel potential candidates, including erythropoietin analogues and angiotensin II type 2 receptor anatagonists are currently being evaluated in phase II clinical trials., (© 2015 John Wiley & Sons Ltd.)

Unlabelled: Autonomic and somatic denervation is well established in Parkinson's disease (PD)., Objectives: (1) To determine whether corneal confocal microscopy (CCM) can non-invasively demonstrate small nerve fiber damage in PD. (2) To identify relationships between corneal nerve parameters, intraepidermal nerve fiber density (IENFD) and clinical features of PD., Methods: Twenty-six PD patients and 26 controls underwent CCM of both eyes. 24/26 PD patients and 10/26 controls underwent skin biopsies from the dorsa of both feet. PD patients underwent assessment of parasympathetic function [deep breathing heart rate variability (DB-HRV)], autonomic symptoms [scale for outcomes in Parkinson's disease - autonomic symptoms (SCOPA-AUT)], motor symptoms [UPDRS-III "ON"] and cumulative Levodopa dose., Results: PD patients had significantly reduced corneal nerve fiber density (CNFD) with increased corneal nerve branch density (CNBD) and corneal nerve fiber length (CNFL) compared to controls. CNBD and CNFL but not CNFD correlated inversely with UPDRS-III and SCOPA-AUT. All CCM parameters correlated strongly with DB-HRV. There was no correlation between CCM parameters and disease duration, cumulative Levodopa dose or pain. IENFD was significantly reduced in PD compared to controls and correlated with CNFD and UPDRS-III. However, unlike CCM measures, IENFD correlated with disease duration and cumulative Levodopa dose but not with autonomic dysfunction., Conclusion: CCM identifies corneal nerve fiber pathology, which correlates with autonomic symptoms, parasympathetic deficits and motor scores in patients with PD. IENFD is also reduced and correlates with CNFD and motor symptoms but not parasympathetic deficits, indicating it detects different aspects of peripheral nerve pathology in PD., (Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Background: Impaired glucose tolerance (IGT) is associated with an increased risk of type 2 diabetes (T2DM) and cardiovascular disease. Some but not all studies have reported cardiac autonomic dysfunction in subjects with IGT and there is only one direct study of cardiac innervation in subjects with IGT. The purpose of this study was to assess global and regional cardiac sympathetic innervation and cardiac autonomic function in individuals with IGT., Methods and Results: We undertook (123)I-mIBG scintigraphy and cardiac autonomic function in 15 subjects with IGT and 15 age and sex-matched healthy controls. Early heart to mediastinum ratio (HMR) (1.71 ± 0.17 vs 1.67 ± 0.13, P = .49), late HMR (1.73 ± 0.18 vs 1.73 ± 0.16, P = .97) and washout rate (WR) (18.6 ± 4.2 vs 19.1 ± 7.6%, P = .84), did not differ between subjects with IGT and control subjects. More detailed regional analysis revealed reduced tracer uptake at the apex, base and inferior wall in all subjects and the anterior wall in a minority of subjects. There were no differences in total score (56.6 ± 4.0 vs 53.3 ± 8.4, P = .193), modified score (48.5 ± 3.3 vs 46.2 ± 6.0, P = .215), anterior wall score (10.2 ± 1.3 vs 10.1 ± 1.6, P = .898), inferior wall score (8.9 ± 1.9 vs 7.7 ± 2.6, P = .163), basal score (18.7 ± 1.9 vs 18.2 ± 3.3, P = .636) and tests of cardiac autonomic function between the groups., Conclusion: Global and regional measures of MIBG uptake and washout as well as cardiac autonomic function did not differ between subjects with IGT and healthy controls.

There are multiple neurological complications of cancer and its treatment. This study assessed the utility of the novel non-invasive ophthalmic technique of corneal confocal microscopy in identifying neuropathy in patients with upper gastrointestinal cancer before and after platinum based chemotherapy. In this study, 21 subjects with upper gastrointestinal (oesophageal or gastric) cancer and 21 healthy control subjects underwent assessment of neuropathy using the neuropathy disability score, quantitative sensory testing for vibration perception threshold, warm and cold sensation thresholds, cold and heat induced pain thresholds, nerve conduction studies and corneal confocal microscopy. Patients with gastro-oesophageal cancer had higher heat induced pain (P = 0.04) and warm sensation (P = 0.03) thresholds with a significantly reduced sural sensory (P<0.01) and peroneal motor (P<0.01) nerve conduction velocity, corneal nerve fibre density (CNFD), nerve branch density (CNBD) and nerve fibre length (CNFL) (P<0.0001). Furthermore, CNFD correlated significantly with the time from presentation with symptoms to commencing chemotherapy (r = -0.54, P = 0.02), and CNFL (r = -0.8, P<0.0001) and CNBD (r = 0.63, P = 0.003) were related to the severity of lymph node involvement. After the 3rd cycle of chemotherapy, there was no change in any measure of neuropathy, except for a significant increase in CNFL (P = 0.003). Corneal confocal microscopy detects a small fibre neuropathy in this cohort of patients with upper gastrointestinal cancer, which was related to disease severity. Furthermore, the increase in CNFL after the chemotherapy may indicate nerve regeneration.

Metformin, an AMPK activator, has been reported to improve pathological response to chemotherapy in diabetic breast cancer patients. To date, its mechanism of action in cancer, especially in cancer stem cells (CSCs) have not been fully elucidated. In this study, we demonstrated that metformin, but not other AMPK activators (e.g. AICAR and A-769662), synergizes 5-fluouracil, epirubicin, and cyclophosphamide (FEC) combination chemotherapy in non-stem breast cancer cells and breast cancer stem cells. We show that this occurs through an AMPK-dependent mechanism in parental breast cancer cell lines. In contrast, the synergistic effects of metformin and FEC occurred in an AMPK-independent mechanism in breast CSCs. Further analyses revealed that metformin accelerated glucose consumption and lactate production more severely in the breast CSCs but the production of intracellular ATP was severely hampered, leading to a severe energy crisis and impairs the ability of CSCs to repair FEC-induced DNA damage. Indeed, addition of extracellular ATP completely abrogated the synergistic effects of metformin on FEC sensitivity in breast CSCs. In conclusion, our results suggest that metformin synergizes FEC sensitivity through distinct mechanism in parental breast cancer cell lines and CSCs, thus providing further evidence for the clinical relevance of metformin for the treatment of cancers.

Background: Diabetic autonomic neuropathy (DAN) results in increased morbidity and mortality. The early diagnosis of DAN can be difficult and is commonly evaluated using cardiac autonomic function tests as a surrogate. However, they are not widely available, have limited sensitivity and specificity, and can be confounded by concomitant cardiovascular disease and medications., Methods: The diagnostic utility of corneal confocal microscopy for diagnosis of DAN was assessed. Thirty-four diabetic patients without [Composite Autonomic Scoring Scale (CASS)≤2] vs with (CASS>2) DAN and 18 healthy control subjects (HC) underwent detailed assessment of somatic and autonomic neuropathy, Composite Autonomic Symptom Scale (COMPASS), (CASS), and Corneal Confocal Microscopy (CCM)., Results: Corneal nerve fiber density, branch density, and length showed a progressive and significant reduction in patients with DAN vs HC and those without DAN. CCM correlated highly significantly with COMPASS and CASS, and corneal nerve fiber parameters demonstrated a high sensitivity and specificity for diagnosis of DAN., Conclusions: This study demonstrates that corneal nerve damage detected using CCM can be deployed to diagnose subclinical and overt DAN. It therefore represents a rapid, non-invasive, highly sensitive and specific diagnostic test for DAN., (© 2014 Wiley Periodicals, Inc.)

Objective: Impaired glucose tolerance (IGT) through to type 2 diabetes is thought to confer a continuum of risk for neuropathy. Identification of subjects at high risk of developing type 2 diabetes and, hence, worsening neuropathy would allow identification and risk stratification for more aggressive management., Research Design and Methods: Thirty subjects with IGT and 17 age-matched control subjects underwent an oral glucose tolerance test, assessment of neuropathic symptoms and deficits, quantitative sensory testing, neurophysiology, skin biopsy, and corneal confocal microscopy (CCM) to quantify corneal nerve fiber density (CNFD), branch density (CNBD), and fiber length (CNFL) at baseline and annually for 3 years., Results: Ten subjects who developed type 2 diabetes had a significantly lower CNFD (P = 0.003), CNBD (P = 0.04), and CNFL (P = 0.04) compared with control subjects at baseline and a further reduction in CNFL (P = 0.006), intraepidermal nerve fiber density (IENFD) (P = 0.02), and mean dendritic length (MDL) (P = 0.02) over 3 years. Fifteen subjects who remained IGT and 5 subjects who returned to normal glucose tolerance had no significant baseline abnormality on CCM or IENFD but had a lower MDL (P < 0.0001) compared with control subjects. The IGT subjects showed a significant decrease in IENFD (P = 0.02) but no change in MDL or CCM over 3 years. Those who returned to NGT showed an increase in CNFD (P = 0.05), CNBD (P = 0.04), and CNFL (P = 0.05), but a decrease in IENFD (P = 0.02), over 3 years., Conclusions: CCM and skin biopsy detect a small-fiber neuropathy in subjects with IGT who develop type 2 diabetes and also show a dynamic worsening or improvement in corneal and intraepidermal nerve morphology in relation to change in glucose tolerance status., (© 2015 by the American Diabetes Association. Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered.)

Purpose: We examined agreement among experts in the assessment of corneal subbasal nerve tortuosity., Methods: Images of corneal subbasal nerves were obtained from investigators at seven sites (Auckland, Boston, Linköping, Manchester, Oslo, Rostock, and Sydney) using laser-scanning in vivo confocal microscopy. A set of 30 images was assembled and ordered by increasing tortuosity by 10 expert graders from the seven sites. In a first experiment, graders assessed tortuosity without a specific definition and performed grading three times, with at least 1 week between sessions. In a second experiment, graders assessed the same image set using four focused tortuosity definitions. Intersession and intergrader repeatability for the experiments were determined using the Spearman rank correlation., Results: Expert graders without a specific tortuosity definition had high intersession (Spearman correlation coefficient 0.80), but poor intergrader (0.62) repeatability. Specific definitions improved intergrader repeatability to 0.79. In particular, tortuosity defined by frequent small-amplitude directional changes (short range tortuosity) or by infrequent large-amplitude directional changes (long range tortuosity), indicated largely independent measures and resulted in improved repeatability across the graders. A further refinement, grading only the most tortuous nerve in a given image, improved the average correlation of a given grader's ordering of images with the group average to 0.86 to 0.90., Conclusions: Definitions of tortuosity specifying short or long-range tortuosity and considering only the most tortuous nerve in an image improved the agreement in tortuosity grading among a group of expert observers. These definitions could improve accuracy and consistency in quantifying subbasal nerve tortuosity in clinical studies.

Purpose: To assess the image and patient level interrater agreement and repeatability within 1 month for corneal nerve fiber length (CNFL) measured using in vivo corneal confocal microscopy (IVCCM) in children., Methods: Seventy-one subjects (mean [SD] age 14.3 [2.6] years, range 8-18 years; 44 with type 1 diabetes and 27 controls; 36 males and 35 females) were included. 547 images (∼6 images per subject) were analyzed manually by two independent and masked observers. One-month repeat visit images were analyzed by a single masked observer in 21 patients. Automated image analysis was then performed using a specialized computerized software (ACCMetrics)., Results: For CNFL, the ICC (95% CI) were 0.94 (0.93-0.95) for image-level, 0.86 (0.78-0.91) for patient-level, and 0.88 (0.72-0.95) for the 1-month repeat assessment, and the Bland-Altman plots showed minimal bias between observers. Although there was excellent agreement between manual and automated analysis according to an ICC 0.89 (0.82-0.93), the Bland-Altman plot showed a consistent bias with manual measurements providing higher readings., Conclusions: In vivo corneal confocal microscopy image analysis shows good reproducibility with excellent intraindividual and interindividual variability in pediatric subjects. Since the image-level reproducibility is stronger than the patient-level reproducibility, refinement of the method for image selection will likely further increase the robustness of this novel, rapid, and noninvasive approach to detect early neuropathy in children with diabetes. Further studies on the use of IVCCM to identify early subclinical neuropathy in children are indicated.

Purpose: To compare small nerve fiber damage in the central cornea and whorl area in participants with diabetic peripheral neuropathy (DPN) and to examine the accuracy of evaluating these 2 anatomical sites for the diagnosis of DPN., Methods: A cohort of 187 participants (107 with type 1 diabetes and 80 controls) was enrolled. The neuropathy disability score (NDS) was used for the identification of DPN. The corneal nerve fiber length at the central cornea (CNFLcenter) and whorl (CNFLwhorl) was quantified using corneal confocal microscopy and a fully automated morphometric technique and compared according to the DPN status. Receiver operating characteristic analyses were used to compare the accuracy of the 2 corneal locations for the diagnosis of DPN., Results: CNFLcenter and CNFLwhorl were able to differentiate all 3 groups (diabetic participants with and without DPN and controls) (P < 0.001). There was a weak but significant linear relationship for CNFLcenter and CNFLwhorl versus NDS (P < 0.001); however, the corneal location × NDS interaction was not statistically significant (P = 0.17). The area under the receiver operating characteristic curve was similar for CNFLcenter and CNFLwhorl (0.76 and 0.77, respectively, P = 0.98). The sensitivity and specificity of the cutoff points were 0.9 and 0.5 for CNFLcenter and 0.8 and 0.6 for CNFLwhorl., Conclusions: Small nerve fiber pathology is comparable at the central and whorl anatomical sites of the cornea. Quantification of CNFL from the corneal center is as accurate as CNFL quantification of the whorl area for the diagnosis of DPN.

Aim: To quantify corneal ultrastructure using laser scanning in vivo confocal microscopy (IVCM) in patients with keratoconus and control subjects., Methods: Unscarred corneas of 78 keratoconic subjects without a history of contact lens use and 36 age-matched control subjects were evaluated with slit-lamp examination (SLE), corneal topography and laser scanning IVCM. One eye was randomly chosen for analysis. Anterior and posterior stromal keratocyte, endothelial cell and basal epithelial cell densities and sub-basal nerve structure were evaluated., Results: IVCM qualitatively demonstrated enlarged basal epithelial cells, structural changes in sub-basal and stromal nerve fibers, abnormal stromal keratocytes and keratocyte nuclei, and pleomorphism and enlargement of endothelial cells. Compared with control subjects, significant reductions in basal epithelial cell density (5817±306 cells/mm(2) vs 4802±508 cells/mm(2), P<0.001), anterior stromal keratocyte density (800±111 cells/mm(2) vs 555±115 cells/mm(2), P<0.001), posterior stromal keratocyte density (333±34 cells/mm(2) vs 270±47 cells/mm(2), P<0.001), endothelial cell density (2875±223 cells/mm(2) vs 2686±265 cells/mm(2), P<0.001), sub-basal nerve fiber density (31.2±8.4 nerves/mm(2) vs 18.1±9.2 nerves/mm(2), P<0.001), sub-basal nerve fiber length (21.4±3.4 mm/mm(2) vs 16.1±5.1 mm/mm(2), P<0.001), and sub-basal nerve branch density (median 50.0 (first quartile 31.2 - third quartile 68.7) nerve branches/mm(2) vs median 25.0 (first quartile 6.2 - third quartile 45.3) nerve branches/mm(2), P<0.001) were observed in patients with keratoconus., Conclusion: Significant microstructural abnormalities were identified in all corneal layers in the eyes of subjects with keratoconus using IVCM. This non-invasive in vivo technique provides an important means to define and follow progress of microstructural changes in patients with keratoconus.

Objective: Quantitative assessment of small fiber damage is key to the early diagnosis and assessment of progression or regression of diabetic sensorimotor polyneuropathy (DSPN). Intraepidermal nerve fiber density (IENFD) is the current gold standard, but corneal confocal microscopy (CCM), an in vivo ophthalmic imaging modality, has the potential to be a noninvasive and objective image biomarker for identifying small fiber damage. The purpose of this study was to determine the diagnostic performance of CCM and IENFD by using the current guidelines as the reference standard., Research Design and Methods: Eighty-nine subjects (26 control subjects and 63 patients with type 1 diabetes), with and without DSPN, underwent a detailed assessment of neuropathy, including CCM and skin biopsy., Results: Manual and automated corneal nerve fiber density (CNFD) (P < 0.0001), branch density (CNBD) (P < 0.0001) and length (CNFL) (P < 0.0001), and IENFD (P < 0.001) were significantly reduced in patients with diabetes with DSPN compared with control subjects. The area under the receiver operating characteristic curve for identifying DSPN was 0.82 for manual CNFD, 0.80 for automated CNFD, and 0.66 for IENFD, which did not differ significantly (P = 0.14)., Conclusions: This study shows comparable diagnostic efficiency between CCM and IENFD, providing further support for the clinical utility of CCM as a surrogate end point for DSPN., (© 2015 by the American Diabetes Association. Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered.)

Objective: Corneal confocal microscopy is a novel diagnostic technique for the detection of nerve damage and repair in a range of peripheral neuropathies, in particular diabetic neuropathy. Normative reference values are required to enable clinical translation and wider use of this technique. We have therefore undertaken a multicenter collaboration to provide worldwide age-adjusted normative values of corneal nerve fiber parameters., Research Design and Methods: A total of 1,965 corneal nerve images from 343 healthy volunteers were pooled from six clinical academic centers. All subjects underwent examination with the Heidelberg Retina Tomograph corneal confocal microscope. Images of the central corneal subbasal nerve plexus were acquired by each center using a standard protocol and analyzed by three trained examiners using manual tracing and semiautomated software (CCMetrics). Age trends were established using simple linear regression, and normative corneal nerve fiber density (CNFD), corneal nerve fiber branch density (CNBD), corneal nerve fiber length (CNFL), and corneal nerve fiber tortuosity (CNFT) reference values were calculated using quantile regression analysis., Results: There was a significant linear age-dependent decrease in CNFD (-0.164 no./mm(2) per year for men, P < 0.01, and -0.161 no./mm(2) per year for women, P < 0.01). There was no change with age in CNBD (0.192 no./mm(2) per year for men, P = 0.26, and -0.050 no./mm(2) per year for women, P = 0.78). CNFL decreased in men (-0.045 mm/mm(2) per year, P = 0.07) and women (-0.060 mm/mm(2) per year, P = 0.02). CNFT increased with age in men (0.044 per year, P < 0.01) and women (0.046 per year, P < 0.01). Height, weight, and BMI did not influence the 5th percentile normative values for any corneal nerve parameter., Conclusions: This study provides robust worldwide normative reference values for corneal nerve parameters to be used in research and clinical practice in the study of diabetic and other peripheral neuropathies., (© 2015 by the American Diabetes Association. Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered.)

Objective: Corneal innervation is increasingly used as a surrogate marker of human diabetic peripheral neuropathy (DPN) however its temporal relationship with the other microvascular complications of diabetes is not fully established. In this cross-sectional, observational study we aimed to assess whether neuropathy occurred in patients with type 1 diabetes, without retinopathy or microalbuminuria., Materials and Methods: All participants underwent detailed assessment of peripheral neuropathy [neuropathy disability score (NDS), vibration perception threshold (VPT), peroneal motor nerve conduction velocity (PMNCV), sural sensory nerve conduction velocity (SSNCV) and in vivo corneal confocal microscopy (IVCCM)], retinopathy (digital fundus photography) and albuminuria status [albumin: creatinine ratio (ACR)]., Results: 53 patients with Type 1 diabetes with (n=37) and without retinopathy (n=16) were compared to control subjects (n=27). SSNCV, corneal nerve fibre (CNFD) and branch (CNBD) density and length (CNFL) were reduced significantly (p<0.001) in diabetic patients without retinopathy compared to control subjects. Furthermore, CNFD, CNBD and CNFL were also significantly (p<0.001) reduced in diabetic patients without microalbuminuria (n=39), compared to control subjects. Greater neuropathic severity was associated with established retinopathy and microalbuminuria., Conclusions: IVCCM detects early small fibre damage in the absence of retinopathy or microalbuminuria in patients with Type 1 diabetes.

Objective: This study determined if deficits in corneal nerve fiber length (CNFL) assessed using corneal confocal microscopy (CCM) can predict future onset of diabetic peripheral neuropathy (DPN)., Research Design and Methods: CNFL and a range of other baseline measures were compared between 90 nonneuropathic patients with type 1 diabetes who did or did not develop DPN after 4 years. The receiver operator characteristic (ROC) curve was used to determine the capability of single and combined measures of neuropathy to predict DPN., Results: DPN developed in 16 participants (18%) after 4 years. Factors predictive of 4-year incident DPN were lower CNFL (P = 0.041); longer duration of diabetes (P = 0.002); higher triglycerides (P = 0.023); retinopathy (higher on the Early Treatment of Diabetic Retinopathy Study scale) (P = 0.008); nephropathy (higher albumin-to-creatinine ratio) (P = 0.001); higher neuropathy disability score (P = 0.037); lower cold sensation (P = 0.001) and cold pain (P = 0.027) thresholds; higher warm sensation (P = 0.008), warm pain (P = 0.024), and vibration (P = 0.003) thresholds; impaired monofilament response (P = 0.003); and slower peroneal (P = 0.013) and sural (P = 0.002) nerve conduction velocity. CCM could predict the 4-year incident DPN with 63% sensitivity and 74% specificity for a CNFL threshold cutoff of 14.1 mm/mm(2) (area under ROC curve = 0.66, P = 0.041). Combining neuropathy measures did not improve predictive capability., Conclusions: DPN can be predicted by various demographic, metabolic, and conventional neuropathy measures. The ability of CCM to predict DPN broadens the already impressive diagnostic capabilities of this novel ophthalmic marker., (© 2015 by the American Diabetes Association. Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered.)

Purpose: In vivo corneal confocal microscopy (CCM) is increasingly used as a surrogate endpoint in studies of diabetic polyneuropathy (DPN). However, it is not clear whether imaging the central cornea provides optimal diagnostic utility for DPN. Therefore, we compared nerve morphology in the central cornea and the inferior whorl, a more distal and densely innervated area located inferior and nasal to the central cornea., Methods: A total of 53 subjects with type 1/type 2 diabetes and 15 age-matched control subjects underwent detailed assessment of neuropathic symptoms (NPS), deficits (neuropathy disability score [NDS]), quantitative sensory testing (vibration perception threshold [VPT], cold and warm threshold [CT/WT], and cold- and heat-induced pain [CIP/HIP]), and electrophysiology (sural and peroneal nerve conduction velocity [SSNCV/PMNCV], and sural and peroneal nerve amplitude [SSNA/PMNA]) to diagnose patients with (DPN+) and without (DPN-) neuropathy. Corneal nerve fiber density (CNFD) and length (CNFL) in the central cornea, and inferior whorl length (IWL) were quantified., Results: Comparing control subjects to DPN- and DPN+ patients, there was a significant increase in NDS (0 vs. 2.6 ± 2.3 vs. 3.3 ± 2.7, P < 0.01), VPT (V; 5.4 ± 3.0 vs. 10.6 ± 10.3 vs. 17.7 ± 11.8, P < 0.01), WT (°C; 37.7 ± 3.5 vs. 39.1 ± 5.1 vs. 41.7 ± 4.7, P < 0.05), and a significant decrease in SSNCV (m/s; 50.2 ± 5.4 vs. 48.4 ± 5.0 vs. 39.5 ± 10.6, P < 0.05), CNFD (fibers/mm2; 37.8 ± 4.9 vs. 29.7 ± 7.7 vs. 27.1 ± 9.9, P < 0.01), CNFL (mm/mm2; 27.5 ± 3.6 vs. 24.4 ± 7.8 vs. 20.7 ± 7.1, P < 0.01), and IWL (mm/mm2; 35.1 ± 6.5 vs. 26.2 ± 10.5 vs. 23.6 ± 11.4, P < 0.05). For the diagnosis of DPN, CNFD, CNFL, and IWL achieved an area under the curve (AUC) of 0.75, 0.74, and 0.70, respectively, and a combination of IWL-CNFD achieved an AUC of 0.76., Conclusions: The parameters of CNFD, CNFL, and IWL have a comparable ability to diagnose patients with DPN. However, IWL detects an abnormality even in patients without DPN. Combining IWL with CNFD may improve the diagnostic performance of CCM.

Although erythropoietin ameliorates experimental type 2 diabetes with neuropathy, serious side effects limit its potential clinical use. ARA 290, a nonhematopoietic peptide designed from the structure of erythropoietin, interacts selectively with the innate repair receptor that mediates tissue protection. ARA 290 has shown efficacy in preclinical and clinical studies of metabolic control and neuropathy. To evaluate the potential activity of ARA 290 in type 2 diabetes and painful neuropathy, subjects were enrolled in this phase 2 study. ARA 290 (4 mg) or placebo were self-administered subcutaneously daily for 28 d and the subjects followed for an additional month without further treatment. No potential safety issues were identified. Subjects receiving ARA 290 exhibited an improvement in hemoglobin A(1c) (Hb A(1c)) and lipid profiles throughout the 56 d observation period. Neuropathic symptoms as assessed by the PainDetect questionnaire improved significantly in the ARA 290 group. Mean corneal nerve fiber density (CNFD) was reduced significantly compared with normal controls and subjects with a mean CNFD >1 standard deviation from normal showed a significant increase in CNFD compared with no change in the placebo group. These observations suggest that ARA 290 may benefit both metabolic control and neuropathy in subjects with type 2 diabetes and deserves continued clinical evaluation.

Diabetic peripheral neuropathies (DPN) are a heterogeneous group of disorders caused by neuronal dysfunction in patients with diabetes. They have differing clinical courses, distributions, fiber involvement (large or small), and pathophysiology. These complications are associated with increased morbidity, distress, and healthcare costs. Approximately 50% of patients with diabetes develop peripheral neuropathy, and the projected rise in the global burden of diabetes is spurring an increase in neuropathy. Distal symmetrical polyneuropathy (DSPN) with painful diabetic neuropathy, occurring in around 20% of diabetes patients, and diabetic autonomic neuropathy (DAN) are the most common manifestations of DPN. Optimal glucose control represents the only broadly accepted therapeutic option though evidence of its benefit in type 2 diabetes is unclear. A number of symptomatic treatments are recommended in clinical guidelines for the management of painful DPN, including antidepressants such as amitriptyline and duloxetine, the γ-aminobutyric acid analogues gabapentin and pregabalin, opioids, and topical agents such as capsaicin. However, monotherapy is frequently not effective in achieving complete resolution of pain in DPN. There is a growing need for head-to-head studies of different single-drug and combination pharmacotherapies. Due to the ubiquity of autonomic innervation in the body, DAN causes a plethora of symptoms and signs affecting cardiovascular, urogenital, gastrointestinal, pupillomotor, thermoregulatory, and sudomotor systems. The current treatment of DAN is largely symptomatic, and does not correct the underlying autonomic nerve deficit. A number of novel potential candidates, including erythropoietin analogues, angiotensin II receptor type 2 antagonists, and sodium channel blockers are currently being evaluated in phase II clinical trials.

Neuropad is currently a categorical visual screening test that identifies diabetic patients at risk of foot ulceration. The diagnostic performance of Neuropad was compared between the categorical and continuous (image-analysis (Sudometrics)) outputs to diagnose diabetic peripheral neuropathy (DPN). 110 subjects with type 1 and 2 diabetes underwent assessment with Neuropad, Neuropathy Disability Score (NDS), peroneal motor nerve conduction velocity (PMNCV), sural nerve action potential (SNAP), Deep Breathing-Heart Rate Variability (DB-HRV), intraepidermal nerve fibre density (IENFD), and corneal confocal microscopy (CCM). 46/110 patients had DPN according to the Toronto consensus. The continuous output displayed high sensitivity and specificity for DB-HRV (91%, 83%), CNFD (88%, 78%), and SNAP (88%, 83%), whereas the categorical output showed high sensitivity but low specificity. The optimal cut-off points were 90% for the detection of autonomic dysfunction (DB-HRV) and 80% for small fibre neuropathy (CNFD). The diagnostic efficacy of the continuous Neuropad output for abnormal DB-HRV (AUC: 91%, P = 0.0003) and CNFD (AUC: 82%, P = 0.01) was better than for PMNCV (AUC: 60%). The categorical output showed no significant difference in diagnostic efficacy for these same measures. An image analysis algorithm generating a continuous output (Sudometrics) improved the diagnostic ability of Neuropad, particularly in detecting autonomic and small fibre neuropathy.

Painful diabetic neuropathy (PDN) is a debilitating consequence of diabetes that may be present in as many as one in five patients with diabetes. The objective assessment of PDN is difficult, making it challenging to diagnose and assess in both clinical practice and clinical trials. No single treatment exists to prevent or reverse neuropathic changes or to provide total pain relief. Treatment of PDN is based on three major approaches: intensive glycaemic control and risk factor management, treatments based on pathogenetic mechanisms, and symptomatic pain management. Clinical guidelines recommend pain relief in PDN through the use of antidepressants such as amitriptyline and duloxetine, the γ-aminobutyric acid analogues gabapentin and pregabalin, opioids and topical agents such as capsaicin. Of these medications, duloxetine and pregabalin were approved by the US Food and Drug Administration (FDA) in 2004 and tapentadol extended release was approved in 2012 for the treatment of PDN. Proposed pathogenetic treatments include α-lipoic acid (stems reactive oxygen species formation), benfotiamine (prevents vascular damage in diabetes) and aldose-reductase inhibitors (reduces flux through the polyol pathway). There is a growing need for studies to evaluate the most potent drugs or combinations for the management of PDN to maximize pain relief and improve quality of life. A number of agents are potential candidates for future use in PDN therapy, including Nav 1.7 antagonists, N-type calcium channel blockers, NGF antibodies and angiotensin II type 2 receptor antagonists.

Aims: Neuropad is a simple visual indicator test, with moderate diagnostic performance for diabetic peripheral neuropathy. As it assesses sweating, which is a measure of cholinergic small nerve fibre function, we compared its diagnostic performance against established measures of both large and, more specifically, small fibre damage in patients with diabetes., Methods: One hundred and twenty-seven participants (89 without diabetic peripheral neuropathy and 38 with) aged 57 ± 9.7 years underwent assessment with Neuropad, large nerve fibre assessments: Neuropathy Disability Score, vibration perception threshold, peroneal motor nerve conduction velocity; small nerve fibre assessments: neuropathy symptoms (Diabetic Neuropathy Symptoms score) corneal nerve fibre length and warm perception threshold., Results: Neuropad has a high sensitivity but moderate specificity against large fibre neuropathy assessments: Neuropathy Disability Score (> 2) 70% and 50%, vibration perception threshold (> 14 V) 83% and 53%, and peroneal motor nerve conduction velocity (< 42 m/s) 81% and 54%, respectively. However, the diagnostic accuracy of Neuropad was significantly improved against corneal nerve fibre length (< 14 mm/mm2) with a sensitivity and specificity of 83% and 80%, respectively. Furthermore, the area under the curve for corneal nerve fibre length (85%) was significantly greater than with the Neuropathy Disability Score (66%, P = 0.01) and peroneal motor nerve conduction velocity (70%, P = 0.03). For neuropathic symptoms, sensitivity was 78% and specificity was 60%., Conclusions: The data show the improved diagnostic performance of Neuropad against corneal nerve fibre length. This study underlines the importance of Neuropad as a practical diagnostic test for small fibre neuropathy in patients with diabetes., (© 2014 The Authors. Diabetic Medicine © 2014 Diabetes UK.)

Cobalt-60 (Co-60) is a relatively new source for the application of high-dose rate (HDR) brachytherapy. Radiation dose to the rectum is often a limiting factor in achieving the full prescribed dose to the target during brachytherapy of cervical cancer. The aim of this study was to measure radiation doses to the rectum in-vivo during HDR Co-60 brachytherapy. A total of eleven HDR brachytherapy treatments of cervical cancer were recruited in this study. A series of diodes incorporated in a rectal probe was inserted into the patient's rectum during each brachytherapy procedure. Real-time measured rectal doses were compared to calculated doses by the treatment planning system (TPS). The differences between calculated and measured dose ranged from 8.5% to 41.2%. This corresponds to absolute dose differences ranging from 0.3 Gy to 1.5 Gy. A linear relationship was observed between calculated and measured doses with linear regression R(2) value of 0.88, indicating close association between the measured and calculated doses. In general, absorbed doses for the rectum as calculated by TPS were observed to be higher than the doses measured using the diode probe. In-vivo dosimetry is an important quality assurance method for HDR brachytherapy of cervical cancer. It provides information that can contribute to the reduction of errors and discrepancies in dose delivery. Our study has shown that in-vivo dosimetry is feasible and can be performed to estimate the dose to the rectum during HDR brachytherapy using Co-60., (Copyright © 2014 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.)

Purpose: To investigate longitudinal changes of subbasal nerve plexus (SNP) morphology and its relationship with conventional measures of neuropathy in individuals with diabetes., Methods: A cohort of 147 individuals with type 1 diabetes and 60 age-balanced controls underwent detailed assessment of clinical and metabolic factors, neurologic deficits, quantitative sensory testing, nerve conduction studies, and corneal confocal microscopy at baseline and four subsequent annual visits. The SNP parameters included corneal nerve fiber density (CNFD), branch density (CNBD), and fiber length (CNFL), and were quantified using a fully automated algorithm. Linear mixed models were fitted to examine the changes in corneal nerve parameters over time., Results: At baseline, 27% of the participants had mild diabetic neuropathy. All SNP parameters were significantly lower in the neuropathy group compared with controls (P < 0.05). Overall, 89% of participants examined at baseline also completed the final visit. There was no clinically significant change to health and metabolic parameters and neuropathy measures from baseline to the final visit. Linear mixed model revealed a significant linear decline of CNFD (annual change rate, -0.9 nerve/mm(2), P = 0.01) in the neuropathy group compared with controls, which was associated with age (β = -0.06, P = 0.04) and duration of diabetes (β = -0.08, P = 0.03). In the neuropathy group, absolute changes of CNBD and CNFL showed moderate correlations with peroneal conduction velocity and cold sensation threshold, respectively (r, 0.38 and 0.40, P < 0.05)., Conclusions: This study demonstrates dynamic small fiber damage at the SNP, thus providing justification for our ongoing efforts to establish corneal nerve morphology as an appropriate adjunct to conventional measures of diabetic peripheral neuropathy., (Copyright 2014 The Association for Research in Vision and Ophthalmology, Inc.)