Search

Background: Arterial duplex ultrasound (DUS) and ankle-brachial indices (ABIs) are accepted methods for assessing lower limb arterial perfusion. However, in a significant number of diabetic patients, medial wall calcification often precludes an ABI measurement. Direct, noninvasive duplex imaging of the pedal arch in the setting of peripheral arterial disease (PAD) has not been well evaluated. Although plantar arch interrogation is new to vascular ultrasound, imaging the plantar arteries appears to be a reliable angiographic technique for critical limb ischemia. We sought to define the utility of Plantar Acceleration Time as a surrogate for ABIs., Methods: Patients undergoing DUS including Plantar Acceleration Time for suspicion of PAD were retrospectively reviewed in a prospective database over a 1-year period. Two hundred fifty nondiabetic patients (499 limbs) with documented ABI were studied. Plantar Acceleration Time was calculated (milliseconds [msec]) in each limb in the lateral plantar artery. Statistical analyses were performed using linear regression and analysis of variance testing using Microsoft Excel database (version 2016; Microsoft Corp, Redmond, WA). Patients were then grouped into 4 classes based on their clinical symptoms and ABI. Plantar Acceleration Time was similarly grouped into 4 distinct classes and correlated with the clinical and ABI classes., Results: Plantar Acceleration Time correlated significantly with ABI (P < 0.001). There were significant differences in Plantar Acceleration Times between each class based on ABI and clinical presentation (P < 0.001 for each): Class 1 Plantar Acceleration Times 89.9 ± 15.5 msec; Class 2, 152.3 ± 28.4 msec; Class 3, 209.8 ± 25.5 msec, and Class 4, 270.2 ± 35.3 msec., Conclusions: Plantar Acceleration Time demonstrates a high correlation with ABI in patients with compressible arteries. Based on our results we propose the following categories of Plantar Acceleration Time, which appear to correlate with both clinical and ABI findings. ABI of 0.90-1.3 correlates with a Plantar Acceleration Time of 0-120 msec, ABI of 0.69-0.89 correlates with a Plantar Acceleration Time of 121-180 msec, ABI of 0.40-0.68 correlates with a Plantar Acceleration Time of 181-224 msec, and an ABI of 0.00-0.39 correlates with a Plantar Acceleration Time of greater than 225 msec. Further studies are ongoing to confirm whether Plantar Acceleration Time may be a suitable substitute to ABIs in patients with noncompressible arteries that preclude meaningful ABIs and gives more information regarding targeted angiosome perfusion to the foot., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Background: The objective of this study was to assess the ability of a novel, automated Conformité Européenne marked vascular early warning system (VEWS) device to detect peripheral arterial disease in patients with incompressible ankle arteries and non-measurable ankle brachial pressure index (ABPI) secondary to diabetes., Methods: Recruited patients had diabetes, recent magnetic resonance angiography evidence of peripheral arterial disease (PAD), and incompressible vessels on ABPI. VEWS indices of each leg were automatically calculated by using optical infrared and red sensors applied to the foot, with readings obtained with the subject's leg both flat and elevated. Indices <1.03 and ≤0.94 were considered upper and lower diagnostic cutoff limits for PAD. Bollinger scores were calculated from the magnetic resonance angiography. A Best Bollinger Score (BBS) of <4 was defined as no significant PAD., Results: All patients had tissue loss. Per protocol analysis of 28 limbs in 14 patients: VEWS had a sensitivity of 94% and specificity 20% for the detection of PAD at <1.03 cutoff and sensitivity 89% and specificity 80% at ≤0.94 cutoff. There was a good correlation between the VEWS index and BBS (-0.637; P = 0.0003)., Conclusion: VEWS is a safe, simple-to-use, promising tool to assist in the diagnosis of PAD in patients with incompressible vessels due to diabetes., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Background:  When faced with plantar defects, reconstruction of the weight-bearing areas presents unique surgical challenges. Several free flap modalities have been described in this respect, but there remains debate regarding the best-suited flap modality. Aim of this study was to compare free muscle and non-neurotized fasciocutaneous flaps for plantar reconstruction with respect to long-term functional outcomes., Methods:  Overall, 89 patients received 100 free flaps (anterolateral thigh [ALT] n  = 46; gracilis n  = 54) for plantar reconstruction. The data were screened for patients' demographics, as well as perioperative details. Postoperative complications were accounted for and the two groups compared accordingly. All patients were contacted for a long-term follow-up examination., Results:  There were no significant differences between the two groups regarding major (24 vs. 17%; p  = 0.366) and minor surgical complications (61 vs. 70%; p  = 0.318). However, the ALT group showed a significantly higher need for secondary surgeries (39 vs. 19%; p  = 0.022). Sixty-eight patients (76%) returned for long-term follow-up evaluation (mean: 51.2 months, range: 13-71 months). The ALT group showed significantly less pain at the recipient ( p  = 0.0004) and donor ( p  = 0.010) sites, and scar assessment revealed significantly better results ( p  < 0.001). Additionally, the ALT group showed better depth ( p  = 0.017) and superficial ( p  = 0.007) sensation and enabled better shoe provision ( p  = 0.014)., Conclusion:  Both the free ALT and gracilis flaps are well suited for plantar reconstruction, yielding overall similar functional outcomes. However, the ALT flap produces less scarring and pain, while showing better recovery of sensation and enabling better shoe provision. The ALT flap thus presents our preferred option., Competing Interests: None declared., (Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.)

Background: Patency of the pedal-plantar arch limits risk of amputation in peripheral artery disease (PAD). We examined patients without chronic kidney disease (CKD)/diabetes mellits (DM) [PAD-control], those with DM without CKD, and those with CKD without DM., Method: Uni- and multivariate logistic regression was used to assess association of CKD with loss of patency of the pedal-plantar arch and presence of tibial or peroneal vessel occlusion. Multivariate models adjusted for age, sex, hypertension, hyperlipidemia and smoking., Results: A total of 419 patients were included [age 75.2 ± 10.3 years, 288 (69%) male]. CKD nearly doubled the unadjusted odds ratio (OR) for loss of patency of the pedal-plantar arch. After adjustment, association remained significant for severe CKD [estimated glomerular filtration rate (eGFR) ≤ 29 ml/min compared with eGFR ≥ 60 ml/min, adjusted (adj.) OR 8.24 (95% confidence interval {CI} 0.99-68.36, p = 0.05)]. CKD was not related to risk of tibial or peroneal artery occlusion [PAD-control versus CKD, adj. OR 1.09 (95% CI 0.49-2.44, p = 0.83)] in contrast to DM [PAD-control versus DM, adj. OR 2.41 (95% CI 1.23-4.72, p = 0.01), CKD versus DM, adj. OR 2.21 (95% CI 0.93-5.22); p = 0.07)]., Conclusions: Below the knee (BTK) vascular pattern differs in patients with either DM or CKD alone. Severe CKD is a risk factor for loss of patency of the pedal-plantar arch.

Aims: Diagnosis of vascular involvement in diabetic foot ulceration (DFU) remains challenging. We conducted a proof of concept study to investigate the feasibility of microwave radiometry (MWR) thermometry for non-invasive differential diagnosis of critical limb ischemia (CLI) in subjects with DFU., Methods: This prospective, multi-center, study included 80 participants, divided into four groups (group N: normal control subjects; group DN: participants with diabetes and verified neuropathic ulcers without vascular involvement; group DC: participants with diabetes and CLI and group NDC: participants with CLI without diabetes). Vascular disease was confirmed with angiography. All patients underwent MWR (RTM-01-RES:University of Bolton, UK) to record mean tissue temperatures at various pre-determined foot sites. Comparisons of temperature measurements between study groups were performed using one-way ANOVA and Dunn tests. ROC analysis was performed to determine sensitivity, specificity and cut-off value of MWR for CLI diagnosis., Results: Temperatures recorded in vicinity to the foot ulcers of participants with diabetes and CLI were similar to those with CLI without diabetes, but significantly lower than in subjects with neuropathic ulcers without vascular involvement and normal controls (group DC:29.30°C±1.89 vs. group NDC:29.18°C±1.78vs. group N:33.01°C±0.45 vs. group DN:33.39°C±1.37;P<.0001). According to ROC analysis, cut-off temperature value to diagnose CLI was <31.8°C (area under the curve: 0.984; 95% CI: 0.965-1.005;P<.001), with a sensitivity of 100.0% (95%CI: 90.26-100.0) and specificity of 88.37% (95% CI: 74.92-96.11)., Conclusions: Tissue temperatures in vicinity to ulcers were significantly lower in participants with CLI, with or without diabetes, compared to non-ischemic controls. MWR could be used for differential diagnosis of arterial ischemia in subjects with DFU., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Background & Aims: Non-invasive lower limb vascular assessment in people at risk of peripheral arterial disease (PAD) including those with diabetes is crucial. There is evidence that standard assessment techniques such as the ankle-brachial index (ABI) may be less effective in people with diabetes. However there is limited evidence for other frequently used tests including continuous wave Doppler (CWD), and the toe-brachial index (TBI). The aim of this study was to determine the sensitivity and specificity of, ABI, CWD and TBI in a population with, and without diabetes., Methods: Participants with and without diabetes who met current guidelines for vascular screening were recruited, and CWD waveforms, an ABI and a TBI were obtained from the right lower limb. Diagnostic accuracy was determined using colour duplex ultrasound (CFDU). Receiver operating characteristic curves were calculated., Results: 117 participants were recruited, seventy-two with diabetes and forty-five without diabetes. CWD had the highest sensitivity in people with diabetes (74%) and without (84%). CWD also had the highest specificity in people with diabetes (74%) and without (84%) compared to both TBI and ABI. In participants with diabetes, the ABI was a poor test, area under the curve: 0.58 (p=0.27)., Conclusions: CWD waveform is more likely to detect significant PAD compared to ABI and TBI in people with and without diabetes., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Assessment of foot perfusion is a vital step in the management of patients with diabetic foot ulceration, in order to understand the risk of amputation and likelihood of wound healing. Underlying peripheral artery disease is a common finding in patients with foot ulceration and is associated with poor outcomes. Assessment of foot perfusion should therefore focus on identifying the presence of peripheral artery disease and to subsequently estimate the effect this may have on wound healing. Assessment of perfusion can be difficult because of the often complex, diffuse and distal nature of peripheral artery disease in patients with diabetes, as well as poor collateralisation and heavy vascular calcification. Conventional methods of assessing tissue perfusion in the peripheral circulation may be unreliable in patients with diabetes, and it may therefore be difficult to determine the extent to which poor perfusion contributes to foot ulceration. Anatomical data obtained on cross-sectional imaging is important but must be combined with measurements of tissue perfusion (such as transcutaneous oxygen tension) in order to understand the global and regional perfusion deficit present in a patient with diabetic foot ulceration. Ankle-brachial pressure index is routinely used to screen for peripheral artery disease, but its use in patients with diabetes is limited in the presence of neuropathy and medial arterial calcification. Toe pressure index may be more useful because of the relative sparing of pedal arteries from medial calcification but may not always be possible in patients with ulceration. Fluorescence angiography is a non-invasive technique that can provide rapid quantitative information about regional tissue perfusion; capillaroscopy, iontophoresis and hyperspectral imaging may also be useful in assessing physiological perfusion but are not widely available. There may be a future role for specialized perfusion imaging of these patients, including magnetic resonance imaging techniques, single-photon emission computed tomography and PET-based molecular imaging; however, these novel techniques require further validation and are unlikely to become standard practice in the near future., (Copyright © 2016 John Wiley & Sons, Ltd.)

Diabetic foot ulceration (DFU) is a chronic complication of diabetes that is characterized by impaired wound healing in the lower extremities. DFU remains a major clinical challenge because of poor understanding of its pathogenic mechanisms. Impaired wound healing in diabetes is characterized by decreased angiogenesis, reduced bone marrow-derived endothelial progenitor cell (EPC) recruitment, and decreased fibroblast and keratinocyte proliferation and migration. Recently, increasing evidence has suggested that increased hypoxic conditions and impaired cellular responses to hypoxia are essential pathogenic factors of delayed wound healing in DFU. Hypoxia-inducible factor-1 (HIF-1, a heterodimer of HIF-1α and HIF-1β) is a master regulator of oxygen homeostasis that mediates the adaptive cellular responses to hypoxia by regulating the expression of genes involved in angiogenesis, metabolic changes, proliferation, migration, and cell survival. However, HIF-1 signalling is inhibited in diabetes as a result of hyperglycaemia-induced HIF-1α destabilization and functional repression. Increasing HIF-1α expression and activity using various approaches promotes angiogenesis, EPC recruitment, and granulation, thereby improving wound healing in experimental diabetes. The mechanisms underlying HIF-1α regulation in diabetes and the therapeutic strategies targeting HIF-1 signalling for the treatment of diabetic wounds are discussed in this review. Further investigations of the pathways involved in HIF-1α regulation in diabetes are required to advance our understanding of the mechanisms underlying impaired wound healing in diabetes and to provide a foundation for developing novel therapeutic approaches to treat DFU., (Copyright © 2016 John Wiley & Sons, Ltd.)

The confluence of several chronic conditions--in particular ageing, peripheral artery disease, diabetes, and chronic kidney disease--has created a global wave of lower limbs at risk for major amputation. While frequently asymptomatic or not lifestyle limiting, at least 1% of the population has peripheral artery disease of sufficient severity to be limb threatening. To avoid the critical error of failing to diagnose ischaemia, all patients with diabetic foot ulcers and gangrene should routinely undergo physiologic evaluation of foot perfusion. Ankle brachial index is useful when measurable, but may be falsely elevated or not obtainable in as many as 30% of patients with diabetic foot ulcers primarily because of medial calcinosis. Toe pressures and skin perfusion pressures are applicable to such patients., (Copyright © 2016 John Wiley & Sons, Ltd.)

Purpose: We evaluated the limitations of the ankle-brachial index (ABI) in the revascularisation of diabetic patients with critical limb ischaemia (CLI) who were undergoing peripheral transluminal angioplasty (PTA) compared with the degree of arterial stenosis and with transcutaneous oxygen tension (TcpO2)., Materials and Methods: This prospective study assessed 250 consecutive diabetic patients in whom we evaluated results of posterior tibial and dorsalis pedis Doppler, ABI, TcpO2, and duplex scans. In total, 104 patients were considered suitable candidates for PTA., Results: In 42% of the patients studied, ABI could either not be used (9.34% due to no signal; 14.02% because the artery could not be compressed) or was incorrect (18.7% before PTA; 15.9% after PTA). In contrast, TcpO2 was determined in all cases. After PTA, vessel stenosis decreased from 58.33±20.07% to 21.87±13.57% (p<0.001), whereas ABI increased from 0.79±0.57 to 0.95±0.47 (p<0.001) and TcpO2 from 27.37±10.40 mmHg to 38.23±10.25 mmHg (p<0.001). A statistical analysis revealed scant correlation between techniques (TcpO2 and ABI) (r=0.14)., Conclusions: ABI shows significant limitations for the diagnosing and treating CLI patients compared with TcpO2.

Thermometry of the plantar skin temperature has been one of the important parameters for assessing ulceration risks in diabetic patients. Recent progress of infrared thermographic technology allows us to obtain imaging of temperature distribution of the whole plantar skin. However, it has not been fully elucidated to what extent the individual variation of the plantar thermographic patterns shows different trends between normal controls and diabetics. In this study, we made a novel framework of conceptual classification with 20 different categories of plantar thermographic patterns according to the foot angiosome concept. The thermographic images from 32 normal volunteers and 129 non-ulcer diabetic patients, recruited from Diabetes Foot Outpatient Clinic of the University of Tokyo Hospital, were allocated to the above-mentioned framework categories. In the normal group, thermographic patterns of more than 65% of feet were allocated to the two typical categories, including the 'butterfly pattern' among the 20 categories, whereas 225 feet (87.2%) of the diabetic groups were variously allocated to 18 out of the 20 categories. This is the first study, which describes detailed plantar thermographic patterns, showing wider variations in the diabetic patients than in the normal subjects. Thermography will be one of the screening options to assess circulatory status in both daily foot care and surgical intervention., (Copyright © 2010 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.)

Background: Pedal bypass grafting has been the method of choice at Na Homolce Hospital's Vascular Surgery Department since 2008., Methods and Results: During the period from June 2008 to December 2011, 29 pedal bypass procedures were performed in 27 patients. No perioperative mortality was recorded. Early occlusion of the graft occurred in three patients and two patients experienced delayed occlusion. Loss of the limb as a result of graft occlusion was unavoidable in two cases and one amputation had to be performed despite a patent graft. The primary patency rate for the period under review is 82.75%, and we were able to salvage the limb in 89.65% of cases. Follow-up results for our cohort are comparable with those from other centres dealing with the same problem., Conclusions: Pedal bypass has excellent early and long-term results and makes a significant contribution to reducing the number of major amputations of the lower limbs.

Background: Macro- and microvascular complications of diabetes are varied and can present with a range of clinical signs and symptoms. Diabetic muscle infarction is a rare vascular complication of diabetes that is often not recognized., Case Report: We report a case of diabetic muscle infarction, where a 65-year-old woman with Type 2 diabetes presented with acute-onset severe pain in her right leg and foot drop., Conclusions: Her foot drop was a result of a concomitant compression nerve injury as a consequence of the muscle oedema following infarction. Our case highlights the importance of early recognition and investigation of atypical presentations of vascular complications of diabetes.

This study evaluated the value of high-frequency ultrasonograpy for early detection of dorsal artery of foot in patients with type 2 diabetes mellitus (MD). Eighty subjects including 40 patients with type 2 MD (T2DM group) and 40 healthy volunteers (NC group) were recruited. The intima-media thickness (IMT), the inner diameter and the perfusion of dorsal artery of foot were measured by using high-frequency ultrasonograpy. Meanwhile, the parameters of vascular elasticity, including stiffness parameter (beta), pressure-strain elastic modulus (Erho), arterial compliance (AC), augment index (AI), and pulse wave conducting velocity (PWVbeta) were detected by means of echo-tracking technique. The results showed that no significant difference was found in the IMT, systolic diameter (Ds), diastolic diameter (Dd) and peak systolic velocity (PSV) between T2DM and NC groups. Erho and PWVbeta were increased, and AC was decreased in T2DM group as compared with those in NC group with the differences being significant (P<0.05 for all). There was no significant difference in beta and AI between T2DM and NC groups. It was concluded that high-frequency ultrasonography in combination with echo-tracking technique is sensitive and non-invasive, and can be used for early detection of sclerosis of the lower extremity artery in patients with type 2 MD.

The main causes for amputations on the lower extremities are dysvascular disease and/or diabetes mellitus. Especially in diabetics tissue preserving surgical techniques should be performed. Due to multimorbidity and high risk of an amputation on the other extremity, the so called "major amputations" ("transtibial" or "transfemoral") should be reduced. Especially in diabetics tissue preserving amputations on the foot or resection techniques on the foot are of importance to prevent major disabilities or handicaps on the patients. For this the surgeon has to have knowledge on all amputation levels on the foot as well as knowledge about prosthetic fitting or shoe techniques. With this a high percentage of good results will prevent the patient from major amputations.

Aim: To determine parameters predictive of avoidance of major (above-the-ankle) amputation after a technically successful peripheral angioplasty (PTA) in patients with diabetes with critical limb ischaemia., Methods: From January 1999 to December 2003, 420 consecutive patients with diabetes admitted to hospital because of critical limb ischaemia underwent peripheral angiography and concomitant technically successful PTA. Transcutaneous oxygen tension (TcPO(2)) was measured before and after PTA. Major amputation at 30 days was recorded., Results: After PTA, the iliac-femoral-popliteal axis was patent in all patients. In 67 patients, all three crural arteries were patent, in 143 patients 2 crural arteries were patent, and in 186 patients one crural artery was patent (104 peroneal, 62 anterior tibial, 20 posterior tibial). In 24 patients, all three crural arteries were occluded. Twenty-two major amputations were performed. Of these, 15 were performed in the 24 patients with occlusion of all the infrapopliteal arteries. Seven of the 186 patients in whom only the peroneal artery was patent required amputation. In patients not requiring amputation, TcPO(2) increased from 15.5 +/- 11.9 to 45.0 +/- 12.0 mmHg (P = 0.000), while in those requiring amputation, TcPO(2) increased from 9.6 +/- 7.7 to 18.6 +/- 8.1 mmHg (P < 0.082). Multivariate analysis indicated an independent role of occlusion of infrapopliteal arteries after PTA (OR 8.20 for every crural obstructed artery, P = 0.022, CI 1.35-49.6) and TcPO(2) after PTA (OR 0.80 for increase of 1 mmHg, P < 0.001, CI 0.74-0.88)., Conclusions: In patients with diabetes, PTA is effective in avoiding major amputation, provided recanalization occurs in at least one tibial artery down to the foot. In a few patients, re-canalization of the peroneal artery alone is not sufficient to avoid major amputation.

Purpose: To prospectively determine the diagnostic performance of a combination of standard bolus-chase magnetic resonance (MR) angiography and MR angiography with time-resolved imaging of contrast kinetics (TRICKS) for depicting severity of peripheral vascular disease of the lower extremity, including the pedal arteries, in diabetic patients with digital subtraction angiography (DSA) as the reference standard., Materials and Methods: An ethical committee approved this study; written informed consent was obtained from patients. Standard three-station and TRICKS MR angiography of the calf and foot were performed in 31 consecutive diabetic patients (23 men, eight women; mean age, 67 years; range, 43-81 years). Two readers separately assessed images of arterial segments as diagnostic or nondiagnostic and graded stenosis. Results were compared with those at DSA when the corresponding arterial segments were considered diagnostic at DSA. Wilcoxon signed rank test was used to determine if a significant difference between imaging techniques existed, and kappa statistics were used to determine interobserver agreement., Results: The difference between standard MR angiography and DSA regarding the number of diagnostic segments in the thigh was not significant (P = .50). A significantly higher number of calf and foot segments was considered diagnostic at TRICKS MR angiography than at standard MR angiography (P < .025). Sixteen of 26 segments in the foot that were considered nondiagnostic at DSA were considered diagnostic at TRICKS MR angiography. Average sensitivity of standard MR angiography for depicting hemodynamically significant arterial stenosis was 84% (reader 1) and 83% (reader 2) in the thigh and 78% (reader 1) and 80% (reader 2) in the calf. For both readers, average specificity was 97% in the thigh and 90% in the calf. Sensitivity and specificity of TRICKS MR angiography in the calf and foot were improved compared with those at standard MR angiography., Conclusion: TRICKS MR angiography of the distal calf and pedal vessels is superior to standard MR angiography regarding the number of diagnostic segments and assessment of the degree of luminal narrowing., ((c) RSNA, 2007.)

Background: Transmetatarsal amputation (TMA) is an operation designed to remove a limited area of irremediable tissue ischemia and/or infection and preserve limb function. Patients are selected for TMA based on degree of tissue loss/infection, adequacy of tissue perfusion at the transmetatarsal level, current ambulatory status, and estimation of the likelihood of postprocedure ambulation. The purpose of this study was to assess the validity of these selection criteria., Methods: An institutional review board-approved retrospective review was conducted of all patients undergoing TMA from January 1, 1997, until January 1, 2006. Information was collected on patient demographics, medical comorbidity, and clinical and surgical variables. Outcome measures included the proportion of patients requiring amputation revision to a more proximal level and ambulatory status at last follow-up., Results: Fifty-two TMAs were performed. In 35 procedures, the skin was left open, and in 17 TMA was closed primarily. Primary indications for the procedure were vascular insufficiency or infection in 50 of 52 patients, whereas 2 patients required amputation for malignancy. The majority (46/52, 89%) of patients were diabetic. After the index TMA, 85 additional operations were required. Only 9 patients (18%) underwent a single operation. Revision of the TMA to a more proximal level was required in 29 of 52 (56%) patients, resulting in 4 Syme, 20 transtibial, and 5 transfemoral amputations. Non-insulin-dependent diabetes was associated with an increased likelihood of revision to a more proximal amputation (odds ratio [OR] = 5.4; 95% confidence interval [CI], 1.2-24). At the time of last follow-up (median 18 months), 37 of 50 (74%) patients were ambulatory (83% for TMAs and 67% for more proximal amputations, P = 0.18). Prior vascular procedures were associated with a significantly decreased likelihood of ambulation (OR = 14; 95% CI, 1.9-103)., Conclusions: Although most patients retain the ability to ambulate after TMA, multiple operations should be anticipated in the majority of patients and revision of a TMA to a more proximal level may be required. These data suggest that current selection criteria for TMA may be inadequate.

As a means of achieving a reduction in the amputation rate in patients with a diabetic foot syndrome, the early diagnosis and specialized treatment of peripheral circulatory disorders is of eminent importance. Treatment includes pressure relief, wound cleanup and stage-oriented local wound management, measures to improve circulation, and the appropriate treatment of bacterial infection. Useful preventive measures include the training of diabetics, regular foot care, and the provision of appropriate footwear.

Microvascular dysfunction is an important component of the pathologic processes that occur in diabetic foot disease. The endothelial abnormalities observed in patients with diabetes mellitus are poorly understood, and evidence suggests that endothelial dysfunction could be involved in the pathogenesis of diabetic macroangiopathy and microangiopathy. With the advent of insulin replacement in the early 1900s and increased efforts toward metabolic control of diabetes, long-term complications of this disease have become apparent. These late-term complications are primarily disorders of the vascular system. This article reviews the process of microvascular dysfunction and how it may relate to the pathogenesis of diabetic foot problems.

Total retrospective clinical-social investigation of 2431 patients with pyo-necrotic complications of the diabetic foot syndrome (DFS) has revealed a considerably increased incidence of pyo-necrotic complications of DFS, mainly at the expense of patients with type II diabetes mellitus. Most of these patients (87.8%) are elderly and senile patients with a middle or severe degree of diabetes (98.2%) and signs of subcompensation or decompensation (87.2%). In 98.0% of the patients there were coexisting diseases. 87.9% of the patients were urgently admitted to hospital with acute pyo-inflammatory processes. A comparison of the results has shown that treatment and interdisciplinary observation in specialized institutions allowed to reduce lethality and number of high amputations more than two times.

Diabetic patients, presenting with both peripheral vascular disease and large soft-tissue defects, are too often treated by primary amputation. A combined revascularization and free-tissue transfer procedure can extend limb salvage in these patients. The authors report their experience over 4 years with 19 diabetic patients with peripheral vascular disease and large soft-tissue defects of the foot requiring free-tissue transfer. Although there was a 100 percent flap survival, early local wound problems occurred in three patients (16.6 percent). The recurrence rate was about 18.7 percent, but no complementary flap procedures were mandatory. With a mean follow-up of 38 months (range: 23 to 55 months), the limb salvage rate was 94.4 percent. Although there was one limb loss and one patient with ambulation difficulties, 16 patients (84.2 percent) were fully rehabilitated and were able to function independently. Despite a rather small series, this study confirms that in selected diabetic patients, a combined approach of vascular and reconstructive surgeons can reduce the limb amputation rate with acceptable complication rates. This combined approach offers major benefits to these patients, especially stable coverage and preservation of ambulation, and should always be considered before amputation.

Vascular and neurological mechanisms are both likely to be involved in foot ulcer. We recently reported a pressure-induced vasodilation (PIV), relying on unmyelinated afferent excitation. We previously found that cutaneous blood flow in response to locally applied pressure might be impaired in diabetic patients because of the combined effects of low cutaneous temperature and alterations in microcirculatory function. Therefore, we aimed to analyze whether, at a relatively high cutaneous temperature, PIV is present in type 1 diabetes and to assess endothelial-dependent vasodilation and endothelium-independent vasodilation. We measured cutaneous blood flow using laser Doppler flowmetry on the head of the first metatarsus in response to applied pressure at 5.0 mmHg/min in warm conditions (29.5 +/- 0.2 degrees C). Responses to iontophoresis of acetylcholine (endothelium dependent) and sodium nitroprusside (endothelium independent) were measured using laser Doppler flowmetry in the forearm. The data indicate that PIV exists at the foot level in normal subjects, whereas it was not found in diabetic patients. In diabetic patients, the nonendothelial-mediated response to sodium nitroprusside was preserved, whereas the endothelial-mediated response to acetylcholine was impaired. These findings might be relevant to the high prevalence of foot ulcer that occurs in diabetic patients.

Background: We sought to establish risk factors predicting the outcome of foot lesions in longstanding diabetic patients with critical foot ischaemia (CFI)., Patients and Methods: We investigated retrospectively 98 consecutive diabetic patients with ischaemic foot lesions. The patients (mean age 70 years, duration of diabetes 21 years) were jointly cared for by specialised diabetologists and vascular surgeons; 75 patients were treated by arterial revascularisation., Results: Good outcome (lesions healing) was observed in 53 patients (54%). Bad outcome was observed in 45 patients: not healing lesions (n = 5), major amputation (n = 19), and death in relation to the foot lesion (n = 21). Patients with good and bad outcome did not differ regarding age, sex, smoking status, type, duration and treatment of diabetes mellitus, presence of neuropathy, coronary heart disease, stroke, previous amputations, current revascularization, and localization of the foot lesion. The risk of bad outcome was increased 8.9 times in patients on dialysis for end-stage renal disease; 7.0 times if surgical complications were present; and 5.4 times with C-reactive protein (CRP) above the second quintile (cut-off value 8 mg/dl)., Conclusion: Management of longstanding diabetic patients with ischaemic foot lesions leaves room for improvement. Dialysis treatment, elevated CRP levels and surgical complications were strongly predictive of non-healing lesions, major amputation and death.

Objective: The aim of this prospective study conducted at a tertiary referral center was to evaluate the efficacy of high-frequency duplex scanning in the preoperative evaluation of potential pedal target vessels. Material and methods The study population consisted of thirty-three consecutive diabetics suffering critical limb ischemia, with indications of infra-popliteal occlusive disease. Duplex ultrasound was performed by an angiologist unaware of any prior imaging procedures. The pedal vessels were divided into four segments. The inner diameter-, the grade of calcification (on a scale from 1-to-3), the maximal systolic velocity, and the resistance index ([V.max syst-V min syst]/V max syst), were assessed by using a 13-MHz probe, and the pedal target vessel best suited for surgery was identified. Results of duplex scanning were compared to (1) the results of selective digital subtraction angiography (DSA) and contrast-enhanced magnetic resonance angiography (CE-MRA) studies interpreted by two radiologists, (2) the site of distal anastomosis predicted by a vascular surgeon according to DSA and CE-MRA studies, (3) the definitive site of distal anastomosis, and (4) early postoperative results (patency at three months)., Results: Duplex scanning depicted significantly more pedal vascular segments than selective DSA- (P =.004, McNemar test). Agreement in predicting the site of distal anastomosis expressed as kappa value as follows: duplex versus DSA/CE-MRA, kappa 0.71;-DSA/CE-MRA versus definitive anastomosis, kappa 0.67; -and duplex versus definitive anastomosis kappa 0.82. Two patients were excluded from surgery as all three imaging modalities failed to demonstrate a pedal target vessel. Two patients had exploratory dissection of a pedal vessel (according to CE-MRA findings) that turned out to be occluded (as predicted by duplex scanning). In one patient the operation had to be terminated due to lack of autologous bypass material. In 31 patients who underwent pedal artery bypass, the resistance index could not be correlated to the run-off as assessed by intra-operative angiography., Conclusions: High-frequency duplex focusing on the vacular-morphology is a worthwhile diagnostic tool to evaluate-potential pedal target vessels and extremely helpful when contrast-related methods (selective DSA, CE-MRA) do not sufficiently depict the pedal vasculature.

The amputation rate in patients with diabetic foot syndrome (DFS) in Germany is still as high as 28,000 per year. Ischemia and osteomyelitis often complicate the DFS. Impaired wound healing frequently requires further surgery with a higher amputation level. The results of treating patients with DFS in our specialized foot care center were evaluated in order to assess our interdisciplinary strategy. Advanced diabetic foot wounds in patients with ischemia and osteomyelitis first require diagnostics concerning polyneuropathy, osteomyelitis, and blood supply. If peripheral arterial vessel disease is present, surgical revascularization by distal bypass grafting is the first and crucially important element of the interdisciplinary approach. Minor amputation or elective resection of the infected bone improves wound healing. Post-interventional care for wounds with secondary healing and prevention of new ulcers are provided in a foot care clinic specialized in diabetes. The clinical and radiological results of 77 patients who underwent this treatment algorithm including bypass surgery and bone resection within 1 year were collected using a standardized questionnaire. Those results were subjected to a historical comparison. Only three patients needed further intervention because of persisting ulcers and osteomyelitis. The frequency of major amputations in all patients with DFS and ischemia combined with osteomyelitis was low (10.3%). This interdisciplinary concept of treatment guarantees a high healing rate in patients even with osteomyelitis and ischemia and allows the reduction of the rate of major amputations. The data obtained allow a fact-based design for future studies.

Low-intensity laser irradiation has been shown to induce wound healing in conditions of reduced microcirculation, which is in part explained by systemic effects. We therefore investigated such a potential systemic effect of low-intensity laser irradiation on skin blood circulation in patients with diabetic microangiopathy. Patients with diabetic microangiopathy were randomized to receive either a single helium-neon (HeNe, 632.8 nm) low-intensity laser irradiation with a dose of 30 J/cm(2) or a sham irradiation over the forefoot region in a double-blind, placebo-controlled clinical study. Skin blood circulation by means of temperature recordings over forefoot regions was detected by infrared thermography. Following a single transcutaneous low-intensity laser irradiation, a rise in skin temperature in both feet of the subjects in the laser group was noted, whereas in both feet of the subjects in the placebo group a drop in skin temperature occurred. The baseline-adjusted skin temperature 15 min after the end of the irradiation was significantly higher in the laser-treated forefeet compared to the placebo-"treated" forefeet (p < 0.0001); the baseline-adjusted difference in the temperature was 1.94 +/- 0.35 degrees C. Simultaneously, the baseline-adjusted skin temperature was significantly higher in the laser-untreated forefeet compared to the placebo-"untreated" forefeet (P < 0.0001); the baseline-adjusted difference was 1.70 +/- 0.33 degrees C. Our data show a significant increase in skin circulation due to athermic laser irradiation in patients with diabetic microangiopathy and point to the possibility of inducing systemic effects.

Hispanic patients suffer from a high rate of leg amputations, far beyond what would be expected from the high prevalence of diabetes in this population. This raises questions about the efficacy of bypass operations across ethnic lines. We focused this review on dorsalis pedis bypasses, as these are frequently performed in diabetic patients. We compared outcomes between Hispanics and non-Hispanics and sought to identify factors predictive of failure or complications. The authors conducted a retrospective review of 144 dorsalis pedis bypasses in 106 men and 29 women with a mean age of 62 years. Eighty-two percent were Hispanic; 96% of cases were done for tissue loss, and 4% for rest pain. Twenty-five percent of patients experienced perioperative complications; these were more frequent in non-Hispanics than Hispanics (40% vs 22%, p = 0.05). The most frequent complications were wound related (11%). The 30-day mortality was 1.5% and 30-day graft thrombosis was 5%. Follow-up ranged from 1 to 62 months and averaged 12 months. Eighty-one percent of the limbs at risk were saved, although 36% of cases required minor foot amputations. Estimated primary graft patency was 68% at 30 months. The 30-month Kaplan-Meier curves for primary patency, assisted patency, and limb salvage were not statistically different between Hispanics and non-Hispanics (p > 0.4). Grafts that remained patent had higher duplex-derived intraoperative flow velocities in the dorsalis pedis artery than grafts that eventually failed (121 +/-69 vs 74 +/-26 cm/sec, p = 0.02). In grafts that remained patent, dorsalis pedis velocity decreased from the perioperative period to the 8 to 12 weeks time point, whereas no change was seen in grafts that eventually failed (mean decline of 48 +/-76 vs 1 +/-58 cm/sec, p = 0.02). No other factors were predictive of graft failure. The results of dorsalis pedis bypass in Hispanic patients compare favorably to those seen in other ethnic groups. This suggests that other factors must account for the high amputation rates seen in Hispanics, such as a frequent occurrence of nonreconstructible disease or unaccounted for cardiovascular risk factors. The usefulness of duplex-derived flow velocities in the dorsalis pedis to predict long-term graft patency warrants further investigation.

Objective: The purpose of this study was to evaluate the performance of pedal bypass grafts to foot vessels detected by magnetic resonance angiography (MRA) that were occult in conventional angiography in patients with diabetes mellitus and severe arterial occlusive disease., Methods: Vascular surgery and radiology registries were reviewed for patients with pedal bypass grafts to arteries that were not detected with digital subtraction angiography but unmasked with MRA. From December 1997 to March 1999, 15 patients (mean age, 73 +/- 8 years) were identified and analyzed retrospectively. All the patients were diabetic, with 60% being insulin-dependent. Advanced tissue loss was the operative indication in all the cases. Distal anastomosis was performed to the dorsalis pedis artery in 10 cases and to the plantar artery in five cases, with ipsilateral greater saphenous vein as graft material in all the cases., Results: The perioperative mortality rate was 7% (1 of 15 cases). One graft occlusion resulted in a secondary patency rate of 93.1%. During a mean follow-up examination period of 22 months, no graft occlusions and one major amputation were noted, which resulted in a secondary patency rate of 93.1% and a limb salvage rate of 89.5% at 36 months., Conclusion: Foot vessels that were occult in conventional angiography but could be detected with MRA were shown to be suitable target vessels for pedal bypass grafting with promising results.

Aim: The aim of this retrospective analysis was assessment of both patency and limb salvage rates of diabetic ischemic feet which underwent pedal bypass surgery within the period of 3 years., Material and Methods: Authors evaluated 50 critically ischemic diabetic feet where the pedal bypass was indicated for limb salvage. Total 41 pedal bypasses were performed and median follow-up was 16.7 months (1-39). The free muscle transfer were performed either in one session with or subsequently after the pedal bypass surgery in six limbs., Results: Authors achieved 61% and 76% graft patency and limb salvage rates, respectively, within the median 16.7 months follow-up. All successfully revascularised feet healed up within the median period of 3 months postoperatively. No patient died within 30 days postoperatively., Conclusion: We conclude, that pedal bypass is safe procedure with acceptable limb salvage rate in the medium-term follow-up. Surgeons can markedly extend an indication criterions for limb salvage by exploiting of this technique.

Originally thought to be a disadvantaged outflow source, the dorsalis pedis artery is associated with excellent patency and limb salvage in the diabetic population. The aim of this study was to demonstrate that the dorsalis pedis artery is as durable in nondiabetics as in their diabetic counterparts. During a 21-year period from 1979 to 1999, 299 long lower limb bypasses to the dorsalis pedis artery were performed at our institution. Patient data and outcomes were reviewed from the vascular registry. Statistical analysis and patency rates were compared using chi-squared and log-rank analysis. This study confirms that the dorsalis pedis can be used as an outflow source with durability that is comparable in both diabetics and nondiabetics. No significant difference exists in morbidity, mortality and patency rates. In the nondiabetic, when the dorsalis pedis is the only patent distal vessel, amputation can be avoided if one considers this a suitable option as an outflow source.

Background/aims: Fluorescein dermofluorometry can be used to relate the uptake of fluorescein in the skin to blood flow. We have characterized the uptake of the dye by a wash-in time constant that is inversely proportional to the local blood flow. The purpose of this study was to explore the use of dermofluorometry in the assessment of patients with diabetic microvascular disease., Methods: Fluorescein dermofluorometry was performed in four groups of patients: non-diabetic control patients, diabetic control patients, diabetic patients with chronic foot ulcers, and diabetic patients with acute foot ulcers. The outcomes of the patients with foot ulcers were documented 4-14 months after participation. Following an intravenous injection of sodium fluorescein, the change in the fluorescein signal with time was continuously measured at the plantar surface of the foot. Both the initial slope of the signal and the wash-in time constant were calculated in each subject., Results: Significant differences in the wash-in time constant were found between diabetic and non-diabetic subjects and between diabetic subjects with and without foot ulcers. Of the eight patients with foot ulcers, two of them did not display an early wash-out in the dermofluorometer signal and later both required amputations., Conclusion: The fluorescein wash-in time constant demonstrated better correlation with the presence of diabetic microvascular disease than did the initial slope of the signal. Differences in the wash-in time constants of non-diabetic and diabetic subjects support the hemodynamic hypothesis for the development of microvascular disease. The indication of early wash-out of the fluorescein signal may also be useful in the prediction of ulcer healing.

Purpose: The purpose of this study was to evaluate the results of combining intraoperative balloon angioplasty (IBA) of the superficial femoral artery (SFA) with distal bypass graft originating from the popliteal artery as a method of lower extremity revascularization in diabetic patients with gangrene., Methods: Among 380 infrainguinal bypass grafts performed over a 6-year period, there were 110 reversed saphenous vein bypass grafts to the tibial or pedal arteries to treat diabetic patients with gangrene. Diffuse infrainguinal disease was treated with femoral-distal bypass graft (long; n = 46). Popliteal-distal bypass graft was performed when the inflow femoral artery was not significantly diseased (short; n = 52). Focal SFA stenosis and severe infrageniculate disease were treated with combined IBA of the SFA and distal bypass graft originating from the popliteal artery (combined; n = 12). Follow-up was performed with duplex scan surveillance of both the bypass graft and IBA sites. Treatment groups were compared with life-table analysis., Results: There were no perioperative graft failures or amputations. The perioperative mortality rate was 1% (1 of 110). The 2-year primary patency rates were similar in the three groups: 72% in the long bypass graft group, 82% in the short bypass graft group, and 76% in the combined group (P =.8, log-rank test). SFA IBA sites developed recurrent stenosis in two patients, at 7 and 48 months; both were detected with surveillance and treated with percutaneous transluminal balloon angioplasty. The overall 5-year rate of primary patency was 63%, secondary patency was 78%, limb salvage was 81%, and survival was 35%. There were no significant differences among the three treatment groups with respect to these outcomes., Conclusion: Results with the combined procedure were similar to those achieved with either femoral-distal bypass graft or popliteal-distal bypass graft without SFA IBA. These data suggest that IBA of the inflow SFA may be combined with popliteal to distal bypass graft and that this technique is a reasonable alternative to longer, femoral-origin bypass graft in selected diabetic patients with gangrene.

Diabetes mellitus is the chief medical cause of amputation. The risk of amputation is 15-fold higher in diabetic subjects and 5 out of 6 amputees are diabetic. Among the three risk factors for amputation in diabetic patients-neuropathy, ischemia, and infection-ischemia is the most difficult to quantify. Thus, functional and/or distal foot arteriopathy may be present without any clinical symptoms long before trophic changes occur. Therefore additional vascular explorations, including measurement of systolic toe pressure, must be performed. Physical examination is sufficient to diagnose lower limb arterial disease when ankle pulses are missing, but severe foot ischemia may be present despite minimal clinical signs and normal ankle pulses. Mediacalcinosis alters ankle pressure. Toe pressure is the most reliable test for quantifying ischemia of the diabetic foot. Other investigations such as TcPO(2) measurement, laser-Doppler and capillaroscopy are useful for revealing early functional diabetic microangiopathy, but they can only be done and interpreted in specialized centers.

Use of pedal bypass can salvage limbs of patients with critical ischemia. The aim of this study was to evaluate the results of surgical revascularization of pedal arteries in diabetic patients and to assess the impact of diabetes on long-term outcome. We performed a retrospective analysis of all consecutive pedal bypasses done between January 1, 1987 and December 31, 1997. Demographic data, surgical indications, operative variables, and postoperative results including graft patency and limb salvage were compared between diabetic and nondiabetic patients. The results of this comparison showed that pedal bypass can safely and effectively relieve critical ischemia in diabetic patients. Diabetics have less early graft thrombosis and superior long-term graft patency. Despite higher incidence of renal insufficiency or failure and more tissue loss, diabetics can achieve similar excellent limb salvage rates. This outcome justifies aggressive revascularization of pedal arteries in diabetic as well as nondiabetic patients with critical limb ischemia.

Background: In a substantial number of mainly diabetic patients isolated crural arterial lesions are found to be the underlying cause for severe ischaemic foot lesions. Without revascularisation, patients with this specific occlusion pattern will inevitably face major amputation. To attain limb salvage in this setting, since the early eighties short vein grafts were used to bypass the occluded infrapopliteal arteries. More recently, percutaneous transluminal angioplasty (PTA) was also attempted to avoid limb loss in selected patients., Patients and Methods: Since May 1986 in 125 patients 130 autologous bypass grafts from the BK-popliteal artery or the proximal tibioperoneal arteries to malleolar vessels were performed in the presence of extended crural arterial occlusions and critical foot ischaemia (rest pain 3, tissue loss 127). In another series in 89 limbs (rest pain 5, tissue loss 84) of 84 patients PTA was done to treat 168 focal stenoses of > 50% diameter reduction and 11 short occlusions in a total of 135 crural arteries., Results: Using life-table analysis, primary and secondary cumulative patency rates for short vein grafts with distal graft origin were 90% and 98% at 30 days, 76% and 83% at one year and 46% and 49% at seven years, respectively. The corresponding limb salvage rates amounted to 95%, 80% and 63%. Initial complete or partial technical success after PTA of crural arteries could be obtained in 93%: The limb salvage rates achieved were 95% at 30 days, 82% at one year and 63% at six years., Conclusion: Our results suggest that--depending on the extent of lesions--both short vein grafts as well as PTA are successful complementary treatment modalities to avoid limb loss in predominantly diabetic patients with infrapopliteal artery disease and critical ischaemia.

Aims/hypothesis: We studied 76 patients with Type II (non-insulin-dependent) diabetes mellitus and 16 age-matched non-diabetic subjects (control group) to clarify qualitative and quantitative abnormalities of waveform and flow volume of the popliteal artery., Methods: The 76 diabetic patients comprised 16 patients with occlusive arterial disease in the lower extremities [arteriosclerosis obliterans (ASO) group] and 60 patients free from this disease (non-ASO group). We flow analysed the popliteal artery and measured the phosphocreatine to inorganic phosphate ratio of resting plantar muscles to identify risk factors for foot lesions using gated magnetic resonance two-dimensional cine-mode phase-contrast imaging and 31P spectroscopy., Results: The control and non-ASO groups had a triphasic waveform with systolic, early and late diastolic components. All ASO patients had an abnormal monophasic waveform and a lower ankle brachial index than that of the control and non-ASO groups. To clarify the mechanism of reduced flow volume of lower extremities, we assigned the 60 patients of the non-ASO group to the three subgroups based on their levels of total flow volume of the popliteal artery. The lowest group showed an abnormal triphasic waveform with lower amplitudes of systolic and late diastolic components and flow velocities in foot arteries than those of the highest group although ABI was similar. From stepwise multiple regression analysis, late diastolic flow volume was identified as an independent determinant for the phosphocreatine to inorganic phosphate ratio (r2 = 0.484, p < 0.001)., Conclusion/interpretation: Waveform analysis of popliteal artery provides a powerful tool for identifying impaired peripheral circulation caused by either occlusive arterial disease or increased arterial resistance in diabetic patients.

Background: Diabetic foot syndrome (DFS) is a frequent complication of long-standing diabetes mellitus, occurring in 10 to 30 percent of all diabetics with a vital risk for the affected limb and high mortality rates. Macroangiopathy, diabetic polyneuropathy and infections are trigger factors for DFS. Recent results imply a pathogenic role of functional and structural microcirculatory changes. The exact role of microangiopathy and the value of microcirculatory diagnostic methods in DFS have not yet been defined., Patients and Methods: 78 patients with DFS (28 type I, 50 type II diabetics, mean age 63 years) were evaluated with video capillary microscopy, transcutaneous partial oxygen tension (tcpO2) measurement and laser Doppler fluxmetry (LDF) at the forefoot of the affected leg at admission and after revascularisation. Mean hospital stay was 28 +/- 11.7 days. Patients were stratified according to the etiology of DFS in patients with neuropathic lesions, macroangiopathic ulcers and mixed neuropathic-angiopathic lesions., Results: All groups had impaired microcirculation, and significant differences between groups were found in respect to capillary density. Reactive hyperemia, LDF pattern and tcpO2 did not differ significantly. Microcirculatory examinations did not yield additional information to clinical and Doppler sonographic results., Conclusion: In clinical practice, the role of microcirculation evaluation techniques for diabetic foot syndrome is limited.

A consecutive series of 32 diabetic patients, 16 male and 16 female, who presented to the authors with critical limb ischaemia was reviewed over a two-year period. Atherosclerotic risk factors and co-morbidities were present in 56% of these patients. Diagnostic angiography was performed in all patients. Revascularization was achieved in 91% of the cases with three perioperative deaths. Ten bypasses were anastomosed distally to one of the crural or ankle arteries at the foot. Major amputations were required in five patients who had had revascularization and in 4 of these gross sepsis was the main factor responsible for limb loss despite patent grafts. The primary graft patency rates at one month and one year were 96% and 90% respectively. Surgical reconstruction was possible in the majority of diabetic patients with critical ischaemia and should be offered to patients preferably before the establishment of gross sepsis to improve limb salvage.

In about 50% of all cases with diabetic foot ulcers diabetic angiopathy takes part in pathogenesis: Macroangiopathy leads to local ischemia by diminished microvascular perfusion. Microangiopathy causes microcirculatory alterations impairing wound healing.

Objective: In the present study long-term patency and limb-salvage rates of femoro-distal bypasses were compared for patients suffering from PAOD stage III and IV with and without DM., Methods: Between 1990 and 1994, some 192 femoro-crural bypass procedures were performed; 132 reconstructions were carried out on patients with PAOD, 60 bypasses on patients with PAOD and DM. The two groups did not differ significantly regarding age, gender and risk pattern., Results: The comparison of the two groups showed a significant advantage for the diabetic patients regarding the limb-salvage rate. In both groups there was also a significant difference regarding patency in favour of the diabetics., Conclusion: Patients suffering from DM and PAOD profit from femoro-distal bypasses. An aggressive vasosurgical reconstructive therapy is indicated for these patients.

We studied endothelial-mediated microvascular blood flow in neuropathic diabetic patients to determine the association between endothelial regulation of the microcirculation and the expression of endothelial constitutive nitric oxide synthetase (ecNOS) in the skin. Vasodilation on the dorsal foot in response to heating and iontophoresis of acetylcholine (endothelium-dependent) and sodium nitroprusside (endothelium-independent) were measured using single-point laser Doppler and laser Doppler imaging in diabetic patients with neuropathy (DN), with neuropathy and vascular disease (DI), with Charcot arthropathy (DA), and without complications (D), and in healthy control subjects (C). The response to heat was reduced in the DN (321 [21-629] percentage of increase over the baseline, median [interquartile range]) and DI (225 [122-470]) groups but was preserved in the DA (895 [359-1,229]), D (699 [466-1,029]), and C (810 [440-1,064], P < 0.0001) groups. The endothelial-mediated response to acetylcholine was reduced in the DN (17 [11-25]), DA (22 [2-34]), and DI (13 [2-30]) groups compared with the D (47 [24-58]) and C (44 [31-70], P < 0.001) groups. The non-endothelial-mediated response to sodium nitroprusside was also reduced in the DI (4 [0-18]), DN (17 [9-26]), and DA (21 [11-31]) groups compared with the D (37 [19-41]) and C (44 [26-67], P < 0.0001) groups. There was a significant reduction in vasodilation in the DI group compared with all other groups (P < 0.0001). Full thickness skin biopsies from the dorsum of the foot of 15 DN, 10 DI, and 11 C study subjects were immunostained with antiserum to human ecNOS, the functional endothelial marker GLUT1, and the anatomical endothelial marker von Willebrand factor. The staining intensity of ecNOS was reduced in both diabetic groups. No differences were found among the three groups in the staining intensity of von Willebrand factor and GLUT1. We conclude that the endothelium-dependent and endothelium-independent vasodilations are impaired in diabetic patients predisposed to foot ulceration and that neuropathy is the main factor associated with this abnormality. Reduced expression of ecNOS may be a major contributing factor for endothelial dysfunction. These data provide support for a close association of neuropathy and microcirculation in the pathogenesis of foot ulceration.