Comparing a non-removable total contact cast with a non-removable softcast in diabetic foot ulcers: A retrospective study of a prospective database.

OBJECTIVE: Diabetic foot ulcers (DFUs) are mostly cured by an off-loading cast. Healing ratios of a non-removable Total Contact Softcast (TCS) were compared to a conventional Total Contact Cast (TCC), the latter reporting negative effects on lifestyle and transportation. METHODS: Analysis of prospectively collected data for 2010-2017. Included were patients with a neuropathic DFU. Ischemic ulcers were excluded, as were Charcot arthropathy, non-plantar/non-forefoot ulcer location, and compliance issues. Patients with TCS were compared to TCC. Primary and secondary outcomes were healing ratio and healing time of DFU. RESULTS: 50 patients with 61 cast periods were included. Mean age was 63.7 ± 10.1 years. Overall successful ulcer healing was 71% (43/61). Except for depth of the DFUs, between-group patient characteristics were comparable; deeper DFUs were reported in the TCC group. This group reported 65% healed DFU (22/34), the TCS group 74% (20/27). Mean healing time was 8.4 weeks (95 %CI 5.9-10.8) for TCC and 5.5 weeks (95 %CI 4.2-6.9) for TCS (p = 0.052). Depth of the wound was a confounder. CONCLUSIONS: TCS had a similar DFU healing ratio and a potentially clinically relevant effect (HR 1.47, 95 %CI 0.64-3.38) on healing time (ns). Ulcer depth is important for time to ulcer healing. A randomized study is recommended.

Improved outcomes in patients with diabetic foot ulcers despite of differences in baseline characteristics.

The incidence of diabetes is increasing worldwide with concomitant raising number of patients with diabetic foot disease. Diabetic foot disease treatment has received more attention in the past decades, culminating in the creation of multidisciplinary outpatient clinics, but at the same time, complexity of patients seems to have increased. The aim of this article is to study differences in patient characteristics and outcomes (ulcer healing and ulcer-free survival days) in patients with a diabetic foot ulcer in two prospective cohorts with 15 years in between. Prospective cohort study of all patients in one diabetic foot centre of expertise in 2003-2004 and 2014-2018. Clinical outcomes were determined after a follow-up period of 12 months. Outcomes were differences in baseline characteristics and comorbidities, and differences in ulcer-related outcomes between both cohorts. We included all consecutive diabetic foot ulcer patients from our centre for the period 2003-2004 (n = 79) and 2014-2018 (n = 271). Age (67.0 ± 14.3 vs. 71.6 ± 11.5, p = 0.003) and prevalence of end-stage renal disease (1.3% vs. 7.7%, p = 0.036) were significantly higher in the more recent population. The more recent population had higher healing rate (53.2% vs. 76.4%, p < 0.001), higher median ulcer-free survival days once an ulcer had healed [173 days (IQR 85.3-295.5) vs. 257.0 (IQR 157.0-318.0), p = 0.026], and fewer minor amputations (20.3% vs. 8.1%, p = 0.002). People with diabetic foot ulcers treated in 2014-2018 were older and more frequently diagnosed with ESRD, compared to this population in 2003-2004, while other characteristics were similar; ulcer-related outcomes were better.

The Association between Foot and Ulcer Microcirculation Measured with Laser Speckle Contrast Imaging and Healing of Diabetic Foot Ulcers.

Diagnosis of peripheral artery disease in people with diabetes and a foot ulcer using current non-invasive blood pressure measurements is challenging. Laser speckle contrast imaging (LSCI) is a promising non-invasive technique to measure cutaneous microcirculation. This study investigated the association between microcirculation (measured with both LSCI and non-invasive blood pressure measurement) and healing of diabetic foot ulcers 12 and 26 weeks after measurement. We included sixty-one patients with a diabetic foot ulcer in this prospective, single-center, observational cohort-study. LSCI scans of the foot, ulcer, and ulcer edge were conducted, during baseline and post-occlusion hyperemia. Non-invasive blood pressure measurement included arm, foot, and toe pressures and associated indices. Healing was defined as complete re-epithelialization and scored at 12 and 26 weeks. We found no significant difference between patients with healed or non-healed foot ulcers for both types of measurements (p = 0.135-0.989). ROC curves demonstrated moderate sensitivity (range of 0.636-0.971) and specificity (range of 0.464-0.889), for LSCI and non-invasive blood pressure measurements. Therefore, no association between diabetic foot ulcer healing and LSCI-measured microcirculation or non-invasive blood pressure measurements was found. The healing tendency of diabetic foot ulcers is difficult to predict based on single measurements using current blood pressure measurements or LSCI.

Effectiveness of at-home skin temperature monitoring in reducing the incidence of foot ulcer recurrence in people with diabetes: a multicenter randomized controlled trial (DIATEMP).

INTRODUCTION: The skin of people with diabetic foot disease is thought to heat up from ambulatory activity before it breaks down into ulceration. This allows for early recognition of imminent ulcers. We assessed whether at-home monitoring of plantar foot skin temperature can help prevent ulcer recurrence in diabetes. RESEARCH DESIGN AND METHODS: In this parallel-group outcome-assessor-blinded multicenter randomized controlled trial (7 hospitals, 4 podiatry practices), we randomly assigned people with diabetes, neuropathy, foot ulcer history (<4 years, n=295), or Charcot's neuro-arthropathy (n=9) to usual care (ie, podiatric treatment, education, and therapeutic footwear) or usual care plus measuring skin temperatures at 6-8 plantar sites per foot each day (enhanced therapy). If ∆T>2.2°C between corresponding sites on the left and right foot for two consecutive days, participants were instructed to reduce ambulatory activity until this hotspot disappeared and contact their podiatrist. Primary outcome was ulcer recurrence in 18 months on the plantar foot, interdigital, or medial/lateral/anterior forefoot surfaces; secondary outcome was ulcer recurrence at any foot site. RESULTS: On the basis of intention-to-treat, 44 of 151 (29.1%) participants in enhanced therapy and 57 of 153 (37.3%) in usual care had ulcer recurrence at a primary outcome site (RR: 0.782 (95%CI 0.566 to 1.080), p=0.133). Of the 83 participants in enhanced therapy who measured a hotspot, the 24 subsequently reducing their ambulatory activity had significantly fewer ulcer recurrences (n=3) than those in usual care (RR: 0.336 (95% CI 0.114 to 0.986), p=0.017). Enhanced therapy was effective over usual care for ulcer recurrence at any foot site (RR: 0.760 (95% CI 0.579 to 0.997), p=0.046). CONCLUSIONS: At-home foot temperature monitoring does not significantly reduce incidence of diabetic foot ulcer recurrence at or adjacent to measurement sites over usual care, unless participants reduce ambulatory activity when hotspots are found, or when aiming to prevent ulcers at any foot site. TRIAL REGISTRATION NUMBER: NTR5403.

Development of a prediction model for foot ulcer recurrence in people with diabetes using easy-to-obtain clinical variables.

INTRODUCTION: We aimed to develop a prediction model for foot ulcer recurrence in people with diabetes using easy-to-obtain clinical variables and to validate its predictive performance in order to help risk assessment in this high-risk group. RESEARCH DESIGN AND METHODS: We used data from a prospective analysis of 304 people with foot ulcer history who had 18-month follow-up for ulcer outcome. Demographic, disease-related and organization-of-care variables were included as potential predictors. Two logistic regression prediction models were created: model 1 for all recurrent foot ulcers (n=126 events) and model 2 for recurrent plantar foot ulcers (n=70 events). We used 10-fold cross-validation, each including five multiple imputation sets for internal validation. Performance was assessed in terms of discrimination using area under the receiver operating characteristic curve (AUC) (0-1, 1=perfect discrimination), and calibration with the Brier Score (0-1, 0=complete concordance predicted vs observed values) and calibration graphs. RESULTS: Predictors in model 1 were: a younger age, more severe peripheral sensory neuropathy, fewer months since healing of previous ulcer, presence of a minor lesion, use of a walking aid and not monitoring foot temperatures at home. Mean AUC for model 1 was 0.69 (2SD 0.040) and mean Brier Score was 0.22 (2SD 0.011). Predictors in model 2 were: a younger age, plantar location of previous ulcer, fewer months since healing of previous ulcer, presence of a minor lesion, consumption of alcohol, use of a walking aid, and foot care received in a university medical center. Mean AUC for model 2 was 0.66 (2SD 0.023) and mean Brier Score was 0.16 (2SD 0.0048). CONCLUSIONS: These internally validated prediction models predict with reasonable to good calibration and fair discrimination who is at highest risk of ulcer recurrence. The people at highest risk should be monitored more carefully and treated more intensively than others. TRIAL REGISTRATION NUMBER: NTR5403.

Surgical Treatment of Diabetic Foot Ulcers Complicated by Osteomyelitis with Gentamicin-Loaded Calcium Sulphate-Hydroxyapatite Biocomposite.

Diabetic foot ulcers, complicated by osteomyelitis, can be treated by surgical resection, dead space filling with gentamicin-loaded calcium sulphate-hydroxyapatite (CaS-HA) biocomposite, and closure of soft tissues and skin. To assess the feasibility of this treatment regimen, we conducted a multicenter retrospective cohort study of patients after failed conventional treatments. From 13 hospitals we included 64 patients with forefoot (n = 41 (64%)), midfoot (n = 14 (22%)), or hindfoot (n = 9 (14%)) ulcers complicated by osteomyelitis. Median follow-up was 43 (interquartile range, 20-61) weeks. We observed wound healing in 54 patients (84%) and treatment success (wound healing without ulcer recurrence) in 42 patients (66%). Treatment failures (no wound healing or ulcer recurrence) led to minor amputations in four patients (6%) and major amputations in seven patients (11%). Factors associated with treatment failures in univariable Cox regression analysis were gentamicin-resistant osteomyelitis (hazard ratio (HR), 3.847; 95%-confidence interval (CI), 1.065-13.899), hindfoot ulcers (HR, 3.624; 95%-CI, 1.187-11.060) and surgical procedures with gentamicin-loaded CaS-HA biocomposite that involved minor amputations (HR, 3.965; 95%-CI, 1.608-9.777). In this study of patients with diabetic foot ulcers, complicated by osteomyelitis, surgical treatment with gentamicin-loaded CaS-HA biocomposite was feasible and successful in 66% of patients. A prospective trial of this treatment regimen, based on a uniform treatment protocol, is required.

Semi-Automatic Tracking of Laser Speckle Contrast Images of Microcirculation in Diabetic Foot Ulcers.

Foot ulcers are a severe complication of diabetes mellitus. Assessment of the vascular status of diabetic foot ulcers with Laser Speckle Contrast Imaging (LSCI) is a promising approach for diagnosis and prognosis. However, manual assessment during analysis of LSCI limits clinical applicability. Our aim was to develop and validate a fast and robust tracking algorithm for semi-automatic analysis of LSCI data. The feet of 33 participants with diabetic foot ulcers were recorded with LSCI, including at baseline, during the Post-Occlusive Reactive Hyperemia (PORH) test, and during the Buerger's test. Different regions of interest (ROIs) were used to measure microcirculation in different areas of the foot. A tracking algorithm was developed in MATLAB to reposition the ROIs in the LSCI scans. Manual- and algorithm-tracking of all recordings were compared by calculating the Intraclass Correlation Coefficient (ICC). The algorithm was faster in comparison with the manual approach (90 s vs. 15 min). Agreement between manual- and algorithm-tracking was good to excellent during baseline (ICC = 0.896-0.984; p < 0.001), the PORH test (ICC = 0.790-0.960; p < 0.001), and the Buerger's test (ICC = 0.851-0.978; p < 0.001), resulting in a tracking algorithm that delivers assessment of LSCI in diabetic foot ulcers with results comparable to a labor-intensive manual approach, but with a 10-fold workload reduction.

Infrared thermography for monitoring severity and treatment of diabetic foot infections.

Monitoring of diabetic foot infections is largely based on clinical assessment, which is limited by moderate reliability. We conducted a prospective study to explore monitoring of thermal asymmetry (difference between mean plantar temperature of the affected and unaffected foot) for the assessment of severity of diabetic foot infections. In patients with moderate or severe diabetic foot infections (International Working Group on the Diabetic Foot infection-grades 3 or 4) we measured thermal asymmetry with an advanced infrared thermography setup during the first 4-5 days of in-hospital treatment, in addition to clinical assessments and tests of serum inflammatory markers (white blood cell counts and C-reactive protein levels). We assessed the change in thermal asymmetry from baseline to final assessment, and investigated its association with infection-grades and serum inflammatory markers. In seven included patients, thermal asymmetry decreased from median 1.8°C (range: -0.6 to 8.4) at baseline to 1.5°C (range: -0.1 to 5.1) at final assessment (P = 0.515). In three patients who improved to infection-grade 2, thermal asymmetry at baseline (median 1.6°C (range: -0.6 to 1.6)) and final assessment (1.5°C (range: 0.4 to 5.1)) remained similar (P = 0.302). In four patients who did not improve to infection-grade 2, thermal asymmetry decreased from median 4.3°C (range: 1.8 to 8.4) to 1.9°C (range: -0.1 to 4.4; P = 0.221). No correlations were found between thermal asymmetry and infection-grades (r = -0.347; P = 0.445), CRP-levels (r = 0.321; P = 0.482) or WBC (r = -0.250; P = 0.589) during the first 4-5 days of hospitalization. Based on these explorative findings we suggest that infrared thermography is of no value for monitoring diabetic foot infections during in-hospital treatment.

Infrared 3D Thermography for Inflammation Detection in Diabetic Foot Disease: A Proof of Concept.

BACKGROUND: Thermal assessment of the plantar surface of the foot using spot thermometers and thermal imaging has been proven effective in diabetic foot ulcer prevention. However, with traditional cameras this is limited to single spots or a two-dimensional (2D) view of the plantar side of foot, where only 50% of the ulcers occur. To improve ulcer detection, the view has to be extended beyond 2D. Our aim is to explore for proof of concept the combination of three-dimensional (3D) models with thermal imaging for inflammation detection in diabetic foot disease. METHOD: From eight participants with a current diabetic foot ulcer we simultaneously acquired a 3D foot model and three thermal infrared images using a high-resolution medical 3D imaging system aligned with three smartphone-based thermal infrared cameras. Using spatial transformations, we aimed to map thermal images onto the 3D model, to create the 3D visualizations. Expert clinicians assessed these for quality and face validity as +, +/-, -. RESULTS: We could replace the texture maps (color definitions) of the 3D model with the thermal infrared images and created the first-ever 3D thermographs of the diabetic foot. We then converted these models to 3D PDF-files compatible with the hospital IT environment. Face validity was assessed as + in six and +/- in two cases. CONCLUSIONS: We have provided a proof of concept for the creation of clinically useful 3D thermal foot images to assess the diabetic foot skin temperature in 3D in a hospital IT environment. Future developments are expected to improve the image-processing techniques to result in easier, handheld applications and driving further research.

Ulcer-free survival days and ulcer healing in patients with diabetic foot ulcers: A prospective cohort study.

Healing rates may not give a complete indication of the effectiveness and management of diabetic foot ulcers because of high recurrence rates. The most important outcome for patients is remaining ulcer-free; however, this has hardly been investigated. The aim of our study was to prospectively investigate ulcer-free survival days and ulcer healing in patients with diabetic foot ulcers. This was a prospective cohort study of all referrals to our diabetic foot expertise centre from December 2014 to April 2017. Outcomes were determined after a minimum follow-up period of 12 months. Primary outcomes were ulcer-free survival days and 12-month healing percentages. Predictors for ulcer-free survival days and healing were investigated in multivariate analyses. A total of 158 patients were included. Median ulcer-free survival days in the healed group were 233 days (interquartile range [IQR] 121-312) and 131 days (IQR 0-298) in the overall population. The healing rate at 12-month follow up was 67% (106/158), and the recurrence rate was 31% (33/106). Independent predictors of ulcer-free survival days were duration of diabetes, peripheral artery disease (PAD), cardiovascular disease, end-stage renal disease (ESRD), and infection. Ulcer-free survival days are related to PAD and cardiovascular disease, and ulcer-free survival days should be the main outcome when comparing the effectiveness of management and prevention of the diabetic foot ulcers.

The cost-effectiveness and cost-utility of at-home infrared temperature monitoring in reducing the incidence of foot ulcer recurrence in patients with diabetes (DIATEMP): study protocol for a randomized controlled trial.

BACKGROUND: Home monitoring of foot temperatures in high-risk diabetes patients proves to be a promising approach for early recognition and treatment of pre-signs of ulceration, and thereby ulcer prevention. Despite previous studies demonstrating its efficacy, it is currently not widely applied in (Dutch) health care. METHODS: In a multicenter, outcome-assessor-blinded, randomized controlled trial, 304 patients with diabetes mellitus types I or II, loss of protective sensation based on peripheral neuropathy, and a history of foot ulceration in the preceding 4 years or a diagnosis of Charcot neuro-osteoarthropathy will be included. Enhanced therapy will consist of usual care and additional at-home daily measurement of foot temperatures at six to eight predefined locations on the foot. If a contralateral foot temperature difference of > 2.2 °C is found on two consecutive days, the participant is instructed to contact their podiatrist for further foot diagnosis or treatment, and to reduce ambulatory activity by 50% until temperatures are normalized. Enhanced therapy will be compared to usual care. The primary outcomes are the cost (savings) per patient without a foot ulcer (i.e., cost-effectiveness) and per quality-adjusted life year gained (i.e., cost-utility). The primary clinical outcome in the study is the proportion of patients with foot ulcer recurrence on the plantar foot, apical surfaces of the toes, the interdigital spaces or medial and lateral forefoot surfaces during 18-month follow-up. DISCUSSION: Confirmation of the efficacy of at-home foot temperature monitoring in ulcer prevention, together with assessing its usability, cost-effectiveness and cost-utility, could lead to implementation in Dutch health care, and in many settings across the world. TRIAL REGISTRATION: Netherlands Trial Registration: NTR5403 . Registered on 8 September 2015.

Effect of different casting design characteristics on offloading the diabetic foot.

BACKGROUND: Non-removable knee-high devices, such as a total contact cast (TCC), are recommended for offloading diabetic plantar forefoot ulcers. However, it is insufficiently known how each of the different design characteristics of these devices contribute to offloading the diabetic foot. RESEARCH QUESTION: What is the offloading effect of the different design characteristics that make up a non-removable knee-high cast for people with diabetes and active or previous plantar forefoot ulcers? METHODS: Sixteen persons with diabetes, peripheral neuropathy and a healed or active plantar forefoot ulcer had their plantar pressures measured during walking in a non-removable knee-high device (TCC), in that device made removable (BTCC), in that device made below-ankle (cast shoe), in that cast shoe worn with a different walking sole and in a newly made cast shoe without a custom-moulded foot-device interface. Peak pressures, force-time integral, and perceived walking comfort were assessed. RESULTS: Compared with the BTCC, peak pressures in the TCC were 47% (P = 0.028), 26% (P = 0.003) and 15% (P = 0.050) lower at the hallux, midfoot and (previous) ulcer location, respectively. Compared to the cast shoe, peak pressures in the BTCC were 39-43% and 47% (both P < 0.001) lower in the forefoot regions and (previous) ulcer location, respectively. The total force-time integral was 21% and 11% (P < 0.007) lower in the TCC and BTCC compared to the cast shoe. Perceived walking comfort was 5.6 in the TCC and 6.5 in the BTCC (P = 0.037). Effects of the other design characteristics (i.e. walking sole and plantar moulding) were non-significant. SIGNIFICANCE: The TCC gives superior offloading, mostly because of being a knee-high and non-removable device, providing an optimal 'shaft effect'. The TCC does, however, negatively affect walking comfort. These results aid decision-making in offloading diabetic plantar forefoot ulcers.

An exploratory study on differences in cumulative plantar tissue stress between healing and non-healing plantar neuropathic diabetic foot ulcers.

BACKGROUND: Mechanical stress is important in causing and healing plantar diabetic foot ulcers, but almost always studied as peak pressure only. Measuring cumulative plantar tissue stress combines plantar pressure and ambulatory activity, and better defines the load on ulcers. Our aim was to explore differences in cumulative plantar tissue stress between people with healing and non-healing plantar diabetic foot ulcers. METHODS: We analyzed a subgroup of 31 patients from a randomized clinical trial, treated with a removable offloading device for their plantar diabetic forefoot ulcer. We measured in-device dynamic plantar pressure and daily stride count to calculate cumulative plantar tissue stress at the ulcer location and associated this with ulcer healing and ulcer surface area reduction at four weeks (Student's t and chi-square test for significance, Cohen's d for effect size). FINDINGS: In 12 weeks, 68% (n = 21) of the ulcers healed and 32% (n = 10) did not. No statistically significant differences were found for cumulative plantar tissue stress, plantar pressure or ambulatory activity between people with healed and not-healed ulcers. Cumulative plantar tissue stress was 25% lower for people with healed ulcers (155 vs. 207 MPa·s/day; P = 0.71; Effect size: d = 0.29). Post-hoc analyses in the 27 patients who self-reported to be adherent to wearing the device showed that cumulative plantar tissue stress was 49% lower for those who reached ≥75% ulcer surface area reduction at four weeks (140 vs. 275 MPa·s/day; P = 0.09; d = 0.76); smaller differences and effect sizes were found for peak pressure (24%), peak pressure-time integral (30%) and ambulatory activity (26%); (P-value range: 0.14-0.97; Cohen's d range: 0.14-0.70). INTERPRETATION: Measuring cumulative plantar tissue stress may provide insight beyond that obtained from plantar pressure or ambulatory activity alone, with regard to diabetic foot ulcer healing using removable offloading devices. These explorative findings provide baseline data for further studies on this relevant topic.

The efficacy of removable devices to offload and heal neuropathic plantar forefoot ulcers in people with diabetes: a single-blinded multicentre randomised controlled trial.

Non-removable offloading is the 'gold standard' treatment for neuropathic diabetic plantar forefoot ulcers. However, removable offloading is the common 'standard of care'. We compared three removable offloading devices for ulcer healing efficacy. In this multicentre, randomised controlled trial, 60 persons with neuropathic diabetic plantar forefoot ulcers were randomly assigned to wear a custom-made knee-high cast [BTCC (bivalved TCC)], custom-made ankle-high cast shoe or a prefabricated ankle-high forefoot-offloading shoe (FOS). Primary outcome was healing at 12 weeks. Dynamic plantar pressures, daily stride count and treatment adherence were assessed on a randomly selected subset (n = 35). According to intention-to-treat analysis, 58% of patients healed with BTCC [OR 0·77 (95% CI 0·41-1·45) versus FOS], 60% with cast shoe [OR 0·81 (95% CI 0·44-1·49) versus FOS] and 70% with FOS (P = 0·70). Mean ± SD peak pressure in kPa at the ulcer site was 81 ± 55 for BTCC, 176 ± 80 for cast shoe and 107 ± 52 for FOS (P = 0·005); stride count was 4150 ± 1626, 3514 ± 1380 and 4447 ± 3190, respectively (P = 0·71); percentage of 2-week intervals that patients wore the device <50% of time was 17·3%, 5·2% and 4·9%, respectively. Non-significant differences in healing efficacy between the three devices suggest that, when non-removable offloading is contraindicated or not available, each can be used for plantar forefoot ulcer offloading. Efficacy is lower than previously found for non-removable offloading maybe because suboptimal adherence and high stride count expose the patient to high repetitive stresses. These factors should be carefully considered in decision making regarding ulcer treatment.

Automatic detection of diabetic foot complications with infrared thermography by asymmetric analysis.

Early identification of diabetic foot complications and their precursors is essential in preventing their devastating consequences, such as foot infection and amputation. Frequent, automatic risk assessment by an intelligent telemedicine system might be feasible and cost effective. Infrared thermography is a promising modality for such a system. The temperature differences between corresponding areas on contralateral feet are the clinically significant parameters. This asymmetric analysis is hindered by (1) foot segmentation errors, especially when the foot temperature and the ambient temperature are comparable, and by (2) different shapes and sizes between contralateral feet due to deformities or minor amputations. To circumvent the first problem, we used a color image and a thermal image acquired synchronously. Foot regions, detected in the color image, were rigidly registered to the thermal image. This resulted in 97.8% ± 1.1% sensitivity and 98.4% ± 0.5% specificity over 76 high-risk diabetic patients with manual annotation as a reference. Nonrigid landmark-based registration with B-splines solved the second problem. Corresponding points in the two feet could be found regardless of the shapes and sizes of the feet. With that, the temperature difference of the left and right feet could be obtained.

An internal iliac artery aneurysm causing sudden buttock ischemia and nerve root compression.

Acute buttock ischemia can be a consequence of aneurysmatic disease and has a dramatic presentation. This case report describes an otherwise healthy patient with a simultaneous onset of buttock ischemia combined with sciatic nerve compression caused by a small distal internal iliac artery aneurysm. Coiling of the aneurysm prevented thromboembolism recurrence but was only partially successful in reducing the symptoms of nerve compression. Given the serious consequences, prophylactic treatment independent of aneurysm diameter can be considered.

Diagnostic values for skin temperature assessment to detect diabetes-related foot complications.

BACKGROUND: Skin temperature assessment is a promising modality for early detection of diabetic foot problems, but its diagnostic value has not been studied. Our aims were to investigate the diagnostic value of different cutoff skin temperature values for detecting diabetes-related foot complications such as ulceration, infection, and Charcot foot and to determine urgency of treatment in case of diagnosed infection or a red-hot swollen foot. MATERIALS AND METHODS: The plantar foot surfaces of 54 patients with diabetes visiting the outpatient foot clinic were imaged with an infrared camera. Nine patients had complications requiring immediate treatment, 25 patients had complications requiring non-immediate treatment, and 20 patients had no complications requiring treatment. Average pixel temperature was calculated for six predefined spots and for the whole foot. We calculated the area under the receiver operating characteristic curve for different cutoff skin temperature values using clinical assessment as reference and defined the sensitivity and specificity for the most optimal cutoff temperature value. Mean temperature difference between feet was analyzed using the Kruskal-Wallis tests. RESULTS: The most optimal cutoff skin temperature value for detection of diabetes-related foot complications was a 2.2°C difference between contralateral spots (sensitivity, 76%; specificity, 40%). The most optimal cutoff skin temperature value for determining urgency of treatment was a 1.35°C difference between the mean temperature of the left and right foot (sensitivity, 89%; specificity, 78%). CONCLUSIONS: Detection of diabetes-related foot complications based on local skin temperature assessment is hindered by low diagnostic values. Mean temperature difference between two feet may be an adequate marker for determining urgency of treatment.

Statistical analysis of spectral data: a methodology for designing an intelligent monitoring system for the diabetic foot.

Early detection of (pre-)signs of ulceration on a diabetic foot is valuable for clinical practice. Hyperspectral imaging is a promising technique for detection and classification of such (pre-)signs. However, the number of the spectral bands should be limited to avoid overfitting, which is critical for pixel classification with hyperspectral image data. The goal was to design a detector/classifier based on spectral imaging (SI) with a small number of optical bandpass filters. The performance and stability of the design were also investigated. The selection of the bandpass filters boils down to a feature selection problem. A dataset was built, containing reflectance spectra of 227 skin spots from 64 patients, measured with a spectrometer. Each skin spot was annotated manually by clinicians as "healthy" or a specific (pre-)sign of ulceration. Statistical analysis on the data set showed the number of required filters is between 3 and 7, depending on additional constraints on the filter set. The stability analysis revealed that shot noise was the most critical factor affecting the classification performance. It indicated that this impact could be avoided in future SI systems with a camera sensor whose saturation level is higher than 106, or by postimage processing.

Infrared thermal imaging for automated detection of diabetic foot complications.

BACKGROUND: Although thermal imaging can be a valuable technology in the prevention and management of diabetic foot disease, it is not yet widely used in clinical practice. Technological advancement in infrared imaging increases its application range. The aim was to explore the first steps in the applicability of high-resolution infrared thermal imaging for noninvasive automated detection of signs of diabetic foot disease. METHODS: The plantar foot surfaces of 15 diabetes patients were imaged with an infrared camera (resolution, 1.2 mm/pixel): 5 patients had no visible signs of foot complications, 5 patients had local complications (e.g., abundant callus or neuropathic ulcer), and 5 patients had diffuse complications (e.g., Charcot foot, infected ulcer, or critical ischemia). Foot temperature was calculated as mean temperature across pixels for the whole foot and for specified regions of interest (ROIs). RESULTS: No differences in mean temperature >1.5 °C between the ipsilateral and the contralateral foot were found in patients without complications. In patients with local complications, mean temperatures of the ipsilateral and the contralateral foot were similar, but temperature at the ROI was >2 °C higher compared with the corresponding region in the contralateral foot and to the mean of the whole ipsilateral foot. In patients with diffuse complications, mean temperature differences of >3 °C between ipsilateral and contralateral foot were found. CONCLUSIONS: With an algorithm based on parameters that can be captured and analyzed with a high-resolution infrared camera and a computer, it is possible to detect signs of diabetic foot disease and to discriminate between no, local, or diffuse diabetic foot complications. As such, an intelligent telemedicine monitoring system for noninvasive automated detection of signs of diabetic foot disease is one step closer. Future studies are essential to confirm and extend these promising early findings.