Nailfold capillaroscopy in systemic lupus erythematosus: A systematic review and critical appraisal.
Cutolo Maurizio,Melsens Karin,Wijnant Sara,Ingegnoli Francesca,Thevissen Kristof,De Keyser Filip,Decuman Saskia,Müller-Ladner Ulf,Piette Yves,Riccieri Valeria,Ughi Nicola,Vandecasteele Els,Vanhaecke Amber,Smith Vanessa
Nailfold capillaroscopy is an easy, non-invasive technique to assess microvascular involvement in rheumatic diseases. Multiple studies describe capillaroscopic changes in systemic lupus erythematosus (SLE), including a wide range of non-specific findings. On behalf of the European League Against Rheumatism (EULAR) study group on microcirculation in rheumatic diseases, a systematic review was done to obtain all original research studies (in English) in which SLE patients had capillaroscopy. Forty such studies are identified. This article firstly provides a résumé of the results of these studies according to capillaroscopic parameters (density, dimensions, morphology, haemorrhages), semi-quantitative assessment and qualitative assessment of capillaroscopy in SLE patients. Secondly, the correlations between capillaroscopic parameters in SLE patients and clinical and laboratory parameters (including auto-immune parameters) are outlined. The following capillaroscopic parameters are found to be significantly more prevalent in SLE patients compared to healthy controls: tortuous capillaries, abnormal morphology and haemorrhages. Hairpin-shaped capillaries are significantly less prevalent than in healthy persons. The semi-quantitatively determined nailfold capillaroscopic score (NFC score) in SLE patients is also higher than in healthy controls. Several correlations between clinical and laboratory parameters and capillaroscopic parameters are identified in the review. Disease activity is correlated with NFC score in seven studies, with abnormal morphology (i.e. "meandering") in one study and with haemorrhages in one study. Frequent attacks of Raynaud's phenomenon (RP) and gangrene are significantly correlated with dilated capillaries. In two studies a possible correlation between anti-SSA antibodies and lower density of capillaries is withheld. About other immune parameters conflicting results are found. In one study a significant negative correlation is found between 24-hour proteinuria and abnormal morphology (i.e. "meandering"). For the first time, an overview of the nailfold capillaroscopic changes that have been described in SLE and their correlations with clinical and laboratory findings is given. Further large-scale research on the identification of capillaroscopic changes in SLE and their correlations with standardised clinical and laboratory parameters, is ongoing at the EULAR study group on microcirculation in rheumatic diseases.
Dynamic Optical Coherence Tomography Capillaroscopy: A New Imaging Tool in Autoimmune Connective Tissue Disease.
Ring Hans Christian,Themstrup Lotte,Banzhaf Christina Alette,Jemec Gregor B E,Mogensen Mette
Importance:Vasculopathy characterized by functional and structural abnormalities of the microcirculation plays an important role in systemic sclerosis and dermatomyositis. Although there are several advantages in using capillaroscopy, the method does not offer insight on the skin architecture, flow status, or morphology of the deeper dermal vessels. Dynamic optical coherence tomography (D-OCT) is a recently developed OCT technique that enables detection of high-speed changes in back-scattered light caused by moving cells in vessels. The high resolution of OCT enables the detection of the papillary loops. Objective:To explore the potential for OCT capillaroscopy of the nailfolds using D-OCT. Design, Setting, and Participants:In this case series study of 4 participants, the nailfolds in 2 patients with systemic sclerosis, 1 patient with dermatomyositis, and a healthy volunteer were scanned using D-OCT. The included patients were all outpatients from the department of dermatology at Bispebjerg Hospital. Data were analyzed from November 2015 to February 2016. Main Outcomes and Measures:Dynamic OCT capillaroscopy revealed a potential for imaging of the capillary morphology, the surrounding skin architecture, and flow status of the capillaries in the nailfold. Moreover, D-OCT quantified evident changes of the blood flow in normal nailfold capillaries after application of nitroglycerine and brimonidine. Results:This case series included 4 adult women. The quantitative measurements of the blood flow in the D-OCT images of the healthy participant showed significant quantitative differences in blood flow before and after application of nitroglycerine (mean difference, 0.035; 95% CI, 0.008-0.061; P = .02) and brimonidine (mean difference, -0.015; 95% CI, -0.082 to -0.039; P < .001). In the dermatomyositis patient, the en face D-OCT images showed a striking detailed Y-shaped dilated capillary correlating with the clinical finding. In the 2 patients with systemic sclerosis, D-OCT depicted megacapillaries, as well as loss of capillaries. Moreover, cross-sectional OCT images demonstrated a characteristic loss of distinct dermo-epidermal junction and more compact dermis with loss of adnexal structures. Conclusions and Relevance:Compared with conventional capillaroscopy, D-OCT offers second-to-none information on nailfold capillary morphology, overall skin architecture, as well as quantitative data on vascular abnormalities and blood flow in the nailfold in a single scan.
Relation of Nailfold Capillaries and Autoantibodies to Mortality in Patients With Raynaud Phenomenon.
Mueller Markus,Gschwandtner Michael E,Gamper Jutta,Giurgea Georgiana-Aura,Charwat-Resl Silvia,Kiener Hans P,Smolen Josef S,Perkmann Thomas,Koppensteiner Renate,Schlager Oliver
BACKGROUND:In incipient Raynaud phenomenon, nailfold capillaroscopy and autoantibody tests are obtained to screen for an emerging connective tissue disease. Whether the presence of abnormal nailfold capillaries and autoantibodies are related to mortality in patients with incipient Raynaud phenomenon is not known. METHODS AND RESULTS:In 2958 consecutive patients (78% women, median age 45 years) with incipient Raynaud phenomenon without previously known connective tissue disease, nailfold capillaroscopy and laboratory tests for antinuclear antibodies (ANA) and ANA subsets were obtained at initial presentation. During a median follow-up period of 9.3 years, 227 women (9.9% of female patients) and 129 men (20% of male patients) with Raynaud phenomenon died. In comparison with a demographically matched standard population, survival was poorer in patients with Raynaud phenomenon (log-rank test P<0.0001). In patients with Raynaud phenomenon, mortality was higher in men than in women (P<0.0001, Cox proportional hazards model). In women, the presence of abnormal nailfold capillaries, ANA, and anti-Scl-70 antibodies were related to an increase in all-cause mortality. The conjoint presence of abnormal nailfold capillaries and autoantibodies was associated with the highest mortality rates. In men, abnormal nailfold capillaries, and ANA and ANA subsets, as well, were not related to survival. In both sexes, patients' age and serum creatinine were associated with mortality. CONCLUSIONS:In Raynaud phenomenon, male sex, age, and serum creatinine are related to mortality. Abnormal nailfold capillaries and autoantibodies are associated with an increase in all-cause mortality in female patients, but not in male patients with Raynaud phenomenon.
Automated structure and flow measurement - a promising tool in nailfold capillaroscopy.
Berks Michael,Dinsdale Graham,Murray Andrea,Moore Tonia,Manning Joanne,Taylor Chris,Herrick Ariane L
OBJECTIVES:Despite increasing interest in nailfold capillaroscopy, objective measures of capillary structure and blood flow have been little studied. We aimed to test the hypothesis that structural measurements, capillary flow, and a combined measure have the predictive power to separate patients with systemic sclerosis (SSc) from those with primary Raynaud's phenomenon (PRP) and healthy controls (HC). METHODS:50 patients with SSc, 12 with PRP, and 50 HC were imaged using a novel capillaroscopy system that generates high-quality nailfold images and provides fully-automated measurements of capillary structure and blood flow (capillary density, mean width, maximum width, shape score, derangement and mean flow velocity). Population statistics summarise the differences between the three groups. Areas under ROC curves (A) were used to measure classification accuracy when assigning individuals to SSc and HC/PRP groups. RESULTS:Statistically significant differences in group means were found between patients with SSc and both HC and patients with PRP, for all measurements, e.g. mean width (μm) ± SE: 15.0 ± 0.71, 12.7 ± 0.74 and 11.8 ± 0.23 for SSc, PRP and HC respectively. Combining the five structural measurements gave better classification (A = 0.919 ± 0.026) than the best single measurement (mean width, A = 0.874 ± 0.043), whilst adding flow further improved classification (A = 0.930 ± 0.024). CONCLUSIONS:Structural and blood flow measurements are both able to distinguish patients with SSc from those with PRP/HC. Importantly, these hold promise as clinical trial outcome measures for treatments aimed at improving finger blood flow or microvascular remodelling.
Microvascular Damage in a Young Female Archer Assessed by Nailfold Videocapillaroscopy: A Case Report.
Sirufo Maria Maddalena,Bassino Enrica Maria,De Pietro Francesca,Ginaldi Lia,De Martinis Massimo
International journal of environmental research and public health
Archers are known to be exposed to the risk of developing various injuries, including less described microvascular damages, which can however heavily affect the performance of athletes. Nailfold videocapillaroscopy is a safe, proven and non-invasive method that allows us to examine the nail capillaries and diagnose vascular anomalies in athletes suffering from the consequences of microtrauma caused by repeated use of fingertips. The detection of defined capillaroscopic pictures is the basis for the follow-up and suggests carrying out further clinical investigations to exclude underlying pathologies. In women this aspect is even more important since they are more frequently affected by autoimmune diseases such as scleroderma which can cause microcirculation alterations. We report the case of a 16-year-old woman who has been practicing archery for five years. She had been complaining for two years about painful fingertips, worsening in the last year. Through videocapillaroscopy, carried out by using a ×200 optical probe-equipped videocapillaroscope connected to image analyzer software (VideoCap software 3.0; DS Medica, Milan, Italy), we detected changes in the microvasculature compatible with a non-specific pattern. The findings of these anomalies suggest a diagnostic analysis aimed at excluding the presence of systemic diseases such as scleroderma. Once these conditions are excluded, and assuming that the documented alterations are due to the particular muscular effort and vibrations to which the fingers are subjected in shooting, we suggest follow-up to keep under control possible further developments and clinical changes. As far as we know, this is the first report that documents and describes the condition of microvascular changes in an archer. Archers, similar to other athletes who mainly use fingertips such as volleyball players, are more exposed to the development of digital traumas that can induce alterations in the microcirculation. We suggest that a periodic capillaroscopy should be included in the health surveillance program of these athletes, in fact this simple, reliable, non-invasive and inexpensive diagnostic tool is able to recognize early signs of microvascular damage and then suggest indications for further investigations and or follow-up.
Nailfold microvascular changes in patients with systemic lupus erythematosus and their associative factors.
Fatemi Alimohammad,Erlandsson Björn-Erik,Emrani Zahra,Etehadtavakol Mahnaz,Smiley Abbas,Karbalaie Abdolamir
OBJECTIVES:The aim of this study was to determine capillaroscopic changes in patients with systemic lupus erythematosus (SLE) and their predictors. METHODS:Fifty-nine SLE patients and 31 controls were enrolled in a cross-sectional study. Nailfold capillaroscopy examinations were performed, and qualitative semi-quantitative and quantitative parameters were evaluated in all fingers. Demographic features and lupus characteristics, such as renal involvement, medications, laboratory data, disease activity (SLEDAI) and damage, were recorded. The predictors of capillaroscopic abnormalities were obtained by backward stepwise regression analysis. RESULTS:Capillary numbers of right hands were significantly lower in patients than in controls [8.74 (1.66) vs. 9.63 (1.80), P = 0.0001]. Capillaries were wider in patients than in controls in right [56.32 μm (16.76) vs. 50.43 μm (10.16), P = 0.002] and left hands [54.40 (15.02) vs. 49.71 (9.77), P = 0.005]. Capillaries were shorter in SLE patients than in controls. Multivariate analysis revealed that the main associative factors of microvascular abnormalities were gender, drinking tea and hydroxychloroquine use for giant capillaries, SLEDAI and low C3 for avascularity and age, lupus nephritis and corticosteroid use for ramification. CONCLUSION:Most nailfold capillaroscopic abnormalities were more common in SLE patients than in controls. Hydroxychloroquine, corticosteroids, SLEDAI, low complement and lupus nephritis may be the major prognostic factors for microvascular changes in SLE patients.
Evaluation of capillary pathologies by nailfold capillaroscopy in patients with psoriasis vulgaris: study protocol for a prospective, controlled exploratory study.
Fink Christine,Kilian Samuel,Bertlich Ines,Hoxha Elti,Bardehle Felicitas,Enk Alexander,Haenssle Holger A
INTRODUCTION:Psoriasis vulgaris was shown to be an independent factor increasing the risk of several comorbidities such as obesity, diabetes and dyslipidaemia with an increased risk of stroke and myocardial infarction. We hypothesise that early endothelial dysfunction, which plays a crucial role in the pathogenesis of atherosclerosis, may be detected by digital video nailfold capillaroscopy (DVNC) at the level of the dermal capillary microvasculature as a surrogate parameter. Nailfolds represent the only body site allowing for a non-invasive assessment of the capillary microvasculature at a horizontal plane. DVNC is a well-established diagnostic tool for in vivo assessment of the peripheral microcirculation by evaluating the morphology of dermal papillary capillaries. To date, reports on morphological changes of the non-lesional nailfold capillaries in patients with psoriasis vulgaris are scarce and the existing data are not conclusive. METHODS AND ANALYSIS:This is a prospective, single-centre, non-randomised, controlled, exploratory study assessing the capillary patterns in 100 subjects affected by psoriasis vulgaris. Non-lesional nailfold capillaries will be imaged by means of DVNC (Optilia Digital Capillaroscopy System, Optilia Instruments AB, Sollentuna, Sweden) in 50 patients affected by psoriasis vulgaris and 50 healthy controls. Assessments will include a qualitative, descriptive analysis of the nailfold capillaries' morphology, as well as a quantitative investigation (frequency, extent) of changes in capillary patterns. Moreover, patients' characteristics associated with the manifestation of nailfold capillaries' pathologies including well-known cardiovascular risk markers will be studied. ETHICS AND DISSEMINATION:Ethical approval was provided by the ethic committee of the medical faculty of the University of Heidelberg (Ethics approval number S-447/2017). The design and the final results of the study will be published and made available to the public. TRIAL REGISTRATION NUMBER:DRKS00012856.
Non-invasive detection of severe neutropenia in chemotherapy patients by optical imaging of nailfold microcirculation.
Bourquard Aurélien,Pablo-Trinidad Alberto,Butterworth Ian,Sánchez-Ferro Álvaro,Cerrato Carolina,Humala Karem,Fabra Urdiola Marta,Del Rio Candice,Valles Betsy,Tucker-Schwartz Jason M,Lee Elizabeth S,Vakoc Benjamin J,Padera Timothy P,Ledesma-Carbayo María J,Chen Yi-Bin,Hochberg Ephraim P,Gray Martha L,Castro-González Carlos
White-blood-cell (WBC) assessment is employed for innumerable clinical procedures as one indicator of immune status. Currently, WBC determinations are obtained by clinical laboratory analysis of whole blood samples. Both the extraction of blood and its analysis limit the accessibility and frequency of the measurement. In this study, we demonstrate the feasibility of a non-invasive device to perform point-of-care WBC analysis without the need for blood draws, focusing on a chemotherapy setting where patients' neutrophils-the most common type of WBC-become very low. In particular, we built a portable optical prototype, and used it to collect 22 microcirculatory-video datasets from 11 chemotherapy patients. Based on these videos, we identified moving optical absorption gaps in the flow of red cells, using them as proxies to WBC movement through nailfold capillaries. We then showed that counting these gaps allows discriminating cases of severe neutropenia (<500 neutrophils per µL), associated with increased risks of life-threatening infections, from non-neutropenic cases (>1,500 neutrophils per µL). This result suggests that the integration of optical imaging, consumer electronics, and data analysis can make non-invasive screening for severe neutropenia accessible to patients. More generally, this work provides a first step towards a long-term objective of non-invasive WBC counting.
Nailfold capillaroscopic changes in patients with chronic viral hepatitis.
Pancar G S,Kaynar T
BACKGROUND:Nailfold capillaroscopy is a highly sensitive, inexpensive, simple, safe, and noninvasive technique used in the investigation of the microcirculation. However, the diseases having a vasculitic component can cause changes in the nailfold capillaries like viral hepatitis, the microvascular characteristics of the nailfold area in HBV and HCV infected individuals have not been systematically investigated. In this study, we investigated possible dermoscopic differences in the vascular appearance of the nailfold capillaries and their association with the disease's clinical status. METHOD:A hundred and forty-seven patients and 147 healthy controls were enrolled in this study. The patients' group consisted of chronic viral hepatitis B (CHB: 54 cases), chronic hepatitis C (CHC: 36 cases) and carrier of hepatitis B virus infection (CRHB: 57 cases). Nailfold capillaroscopy was performed using a digital dermoscope (Molemax II, X30). All capillaroscopy images were evaluated for capillary density, capillary loop enlargement, capillary tortuosities, branching vessels, micro hemorrhages, avascular areas and splinter hemorrhages, and routine laboratory examinations of all patients were performed. RESULTS:Statistical differences in all of the categories of capillary morphology were prominent between the capillary abnormalities of Hepatitis B and the control group, also the capillary abnormality was significant between hepatitis C and the control group (p < 0.01). None of the 147 healthy control had any nailfold capillary changes. There was a significant difference between the CHB-Control and CRHB-Control groups in all of the capillaroscopic changes (p < 0.01). The avascular area was also the most common finding in Hepatitis C and Hepatitis B infected individuals, and capillary dilatation (CD), capillary tortuosity (CT) and capillary enlargement (CE) were the major nailfold capillary changes in both of two diseases. CONCLUSION:Nailfold capillary abnormalities are one of the extrahepatic dermatologic finding which could be a sign of the endothelial tissue damage in chronic viral hepatitis, we do not have any data about the effects of these two usual infections on the nailfold capillary morphology. This is the first study evaluating the microvasculature abnormalities of the nailfold capillaries in hepatitis B and hepatitis C infected individuals by capillaroscopic examination.
Consensus-based evaluation of dermatoscopy versus nailfold videocapillaroscopy in Raynaud's phenomenon linking USA and Europe: a European League against Rheumatism study group on microcirculation in rheumatic diseases project.
Radic Mislav,Snow Marcus,Frech Tracy M,Saketkoo Lesley A,Cutolo Maurizio,Smith Vanessa
Clinical and experimental rheumatology
OBJECTIVES:Nailfold videocapillaroscopy (NVC) is the current gold standard for detection and quantification of capillary abnormalities in Raynaud's phenomenon (RP). The objective of this study is to evaluate the role of dermatoscopy as a further screening tool in RP. METHODS:Nailfold capillaries of RP patients were examined by a hand-held non-contact polarised dermatoscope connected to the digital camera (D1) and connected to an iPad (D2). Both dermatoscopic images were marked with an arrowhead. NVC examination was evaluated at the arrowhead. Single blinded reader performed all examinations. NVC was graded as per standard of European League against Rheumatism (EULAR) study group on microcirculation in rheumatic diseases. Consensus evaluation of dermatoscopy characteristics/grade was determined and each dermatoscopic image was given a final impression of 'normal', 'non-specific' or 'scleroderma' pattern. The final interpretation by both techniques was compared after completion of the blinded reading. RESULTS:Classification of 100 consecutive dermatoscopic images resulted in 37 (wide view) 'non-interpretable', 2 'normal', 48 'non-specific' and 13 'scleroderma' pattern with D1; 23 'non-interpretable', 4 'normal', 52 'non-specific' and 21 'scleroderma' pattern by the experts with D2; 0 non-interpretable, 4 normal, 13 non-specific and 83 'scleroderma' pattern with NVC. CONCLUSIONS:Overall, 50% of dermatoscopic images were classified as non-specific and 30% were classified as non-interpretable in RP patients. However, all images classified by dermatoscopy as "normal" or as overt "scleroderma" pattern were confirmed by concomitant NVC analysis. These findings demonstrate tenuous promise for dermatoscopy as a tool for the initial screening of nailfold capillaries in RP. Further regular work up with NVC is needed to further clarify non-interpretable and non-specific findings possibly related to non-scleroderma patterns.
The Relationship Between Nailfold Microcirculation and Retinal Microcirculation in Healthy Subjects.
Tian Jiaxin,Xie Yuan,Li Meng,Oatts Julius,Han Ying,Yang Yiquan,Shi Yan,Sun Yunxiao,Sang Jinghong,Cao Kai,Xin Chen,Siloka Labisi,Wang Huaizhou,Wang Ningli
Frontiers in physiology
Objective:To evaluate whether the nailfold microcirculation is associated with retinal microcirculation in healthy subjects. Methods:Fifty subjects without systematic and ocular diseases were enrolled. Thickness of peripapillary retinal nerve fiber layer (RNFL), vessel density (VD) of radial peripapillary capillaries (RPCs), and superficial capillary VD in macular zone were measured with optical coherence tomography angiography (OCTA) in left eyes. Nailfold microcirculation, including capillary density, avascular zones, dilated capillaries, and hemorrhages was examined on the fourth digit of each subject's non-dominant (left) hand with nailfold capillaroscopy (NFC). Results:After adjustment for relatively systemic factors, multivariate regression analyses showed a significant direct relationship between RNFL thickness and nailfold capillary density (OR = 1.09; = 0.046). RNFL thickness and RPCs VD were negatively correlated with nailfold avascular zones (OR = 0.855; = 0.007; OR = 0.596; = 0.010). Superficial VD of parafovea was negatively associated with dilated nailfold capillaries (OR = 0.794; = 0.012). Conclusion:In healthy subjects, nailfold capillary lower density and abnormalities are associated with reduced RNFL thickness and retinal VD. The results provide a theoretical foundation for relevant studies on ocular diseases with microvascular abnormalities and could contribute to pathogenesis understanding in the future. NFC and OCTA have the potential to identify risk factors and improve accuracy of the early diagnosis and treatment of ocular diseases, even systemic diseases with any microvascular component in clinical practice. Clinical Trail Registration:http://www.chictr.org.cn/index.aspx, identifier ChiCTR 1800017875.
Assessment of Microcirculation in HIV-Positive Patients with a Noninvasive Method: Nailfold Videocapillaroscopy.
Sarigul Yildirim Figen,Balkarli Ayse
AIDS research and human retroviruses
Chronic inflammation that contributes to the deterioration of the mechanical form of both the vascular wall and the function of endothelial has been shown to cause vascular dysfunction in patients with human immunodeficiency virus (HIV). Nailfold videocapillaroscopy (NVC) is a noninvasive and simple technique used to analyze dermal microvasculature. The aims of our study were to detect the morphological and functional properties of microcirculation in HIV-positive patients utilizing NVC and to compare the results with those obtained from healthy individuals and investigate whether these changes had supported any correlation with HIV. In this prospective study, 51 male HIV-positive patients were the subjects and 59 male healthy individuals made up the control group. Capillaroscopic findings, obtained from both groups by NVC, were evaluated. Tortuosity, a capillaroscopic finding, was significantly higher in the group with HIV ( < .001). In logistic regression analysis, tortuosity [odds ratio (OR), 4.658; = .001], bizarre capillary (OR, 1.733; = .319), and capillary ectasia (OR, 0.867; = .493) were considered significant. The changes of capillaroscopic findings were found to be correlated with HIV. We suggest videocapillaroscopy in the evaluation of microvascular changes in HIV patients, as a dependable contributing method.
Effectiveness and feasibility of nailfold microcirculation test to screen for diabetic peripheral neuropathy.
Hu Guotao,Zhai Fanglong,Mo Feifei,He Li,Shen Weiya,Wang Hailan
Diabetes research and clinical practice
AIMS:The nailfold microcirculation index (MI) is a non-invasive, objective, and highly sensitive blood capillary detection method. This study evaluated the diagnostic efficiency of the nailfold MI relative to the more subjective vibration perception threshold (VPT) examination for early diagnostic screening of diabetic peripheral neuropathy (DPN). METHODS:From February 2015 to February 2016, 227 diabetes mellitus patients and 39 healthy individuals were enrolled. Each subject underwent the MI test and the VPT examination. RESULTS:MI was more closely associated with DPN than age, diabetic duration, smoking, drinking, systolic pressure, serum creatinine, 24-h urinary protein, hypoxia-inducible factor-1α (HIF1A), vascular endothelial growth factor (VEGF), the VEGF receptors Flt-1 and Flt-4, ankle branchial index (ABI), DPN, or DPN stage (OR=11.819). Both the MI and VPT closely correlated with age, diabetic duration, serum creatinine, 24-h urinary protein, HIF1A, VEGF, Flt-1, Flt-4, ABI, DPN, and DPN stage. By the receiver operating characteristic (ROC) curve, the MI diagnostic cutoff point was 2.56, where the corresponding Youden's index was maximum and the area under ROC curve was 0.943. The diagnostic efficiency of MI and VPT were similar. MI and VPT indicated similar percentages of diabetic patients with DPN at the most severe stage, while MI achieved a higher diagnostic rate for the earliest stages. CONCLUSIONS:The nailfold MI is a feasible method for clinical early diagnostic screening of DPN in diabetic patients, and is more objective and reliable than VPT.