Fuzzy spectral clustering for automated delineation of chronic wound region using digital images.

Chronic wound is an abnormal disease condition of localized injury to the skin and its underlying tissues having physiological impaired healing response. Assessment and management of such wound is a significant burden on the healthcare system. Currently, precise wound bed estimation depends on the clinical judgment and remains a difficult task. The paper introduces a novel method for ulcer boundary demarcation and estimation, using optical images captured by a hand-held digital camera. The proposed approach involves gray based fuzzy similarity measure using spatial knowledge of an image. The fuzzy measure is used to construct similarity matrix. The best color channel was chosen by calculating the mean contrast for 26 different color channels of 14 color spaces. It was found that Db color channel has highest mean contrast which provide best segmentation result in comparison with other color channels. The fuzzy spectral clustering (FSC) method was applied on Db color channel for effective delineation of wound region. The segmented wound regions were effectively post-processed using various morphological operations. The performance of proposed segmentation technique was validated by ground-truth images labeled by two experienced dermatologists and a surgeon. The FSC approach was tested on 70 images. FSC effectively segmented targeted ulcer boundary yielding 91.5% segmentation accuracy, 86.7%, Dice index and 79.0%. Jaccard score. The sensitivity and specificity was found to be 87.3% and 95.7% respectively. The performance evaluation shows the robustness of the proposed method of wound area segmentation and its potential to be used for designing patient comfort centric wound care system.

Spectral Clustering for Unsupervised Segmentation of Lower Extremity Wound Beds Using Optical Images.

Chronic lower extremity wound is a complicated disease condition of localized injury to skin and its tissues which have plagued many elders worldwide. The ulcer assessment and management is expensive and is burden on health establishment. Currently accurate wound evaluation remains a tedious task as it rely on visual inspection. This paper propose a new method for wound-area detection, using images digitally captured by a hand-held, optical camera. The strategy proposed involves spectral approach for clustering, based on the affinity matrix. The spectral clustering (SC) involves construction of similarity matrix of Laplacian based on Ng-Jorden-Weiss algorithm. Starting with a quadratic method, wound photographs were pre-processed for color homogenization. The first-order statistics filter was then applied to extract spurious regions. The filter was selected based on the performance, evaluated on four quality metrics. Then, the spectral method was used on the filtered images for effective segmentation. The segmented regions were post-processed using morphological operators. The performance of spectral segmentation was confirmed by ground-truth pictures labeled by dermatologists. The SC results were additionally compared with the results of k-means and Fuzzy C-Means (FCM) clustering algorithms. The SC approach on a set of 105 images, effectively delineated targeted wound beds yielding a segmentation accuracy of 86.73 %, positive predictive values of 91.80 %, and a sensitivity of 89.54 %. This approach shows the robustness of tool for ulcer perimeter measurement and healing progression. The article elucidates its potential to be incorporated in patient facing medical systems targeting a rapid clinical assistance.

Azathioprine-induced bullous Sweet's syndrome: a rare association.

A 52-year-old man presented with high-grade fever, headache and painful vesicular skin rash involving the upper trunk and upper extremities, 8 days after initiation of chemotherapy with azathioprine (50 mg/day), which had been prescribed for acral vitiligo. There was neither any history of preceding respiratory or gastrointestinal tract infection, nor was the patient known to have malignancy, drug hypersensitivity, inflammatory bowel disease, vasculitis or other autoimmune disease. Laboratory results revealed leucocytosis with neutrophilia and markedly elevated acute phase reactants. Antinuclear antibody, perinuclear and cytoplasmic antineutrophil cytoplasmic antibody were found negative. Punch biopsy from skin of the upper trunk revealed dense neutrophilic infiltration of dermis without signs of vasculitis, suggestive of Sweet's syndrome. In view of the temporal association with azathioprine and absence of an obvious alternative aetiology, provisional diagnosis of drug-induced bullous Sweet's syndrome was made. Azathioprine was discontinued and high-dose oral prednisolone initiated. The response was dramatic with resolution of skin lesions within 72 h without further recurrence at fourth week of follow-up.

Disseminated giant porokeratosis and porokeratosis of Mibelli in Bankura and Bardhaman districts, West Bengal, India.

Porokeratosis of Mibelli (PM) is a rare genodermatosis. It is caused by proliferation of abnormal clones of epidermal cells in response to several stimuli, the most important of which is sunlight. Giant porokeratosis is thought to be a variant of PM. We report two cases of disseminated PM and one case of disseminated giant porokeratosis from the Bankura and Bardhaman districts of West Bengal in India; presenting to a single observer in the summer of 2012. Interestingly we have noted that the majority of cases of porokeratosis in India have been reported from West Bengal. Few patients with a single lesion of giant porokeratosis have been reported in world literature. As far as we know, this is the first case report of disseminated giant porokeratosis in world literature.

Syringocystadenoma papilliferum: an unusual presentation.

An 8-year-old boy presented with a rapidly growing, unusually large, fleshy, lobulated, cauliflower-like mass on the lower back. Incisional biopsy revealed the histologic picture of syringocystadenoma papilliferum. The case is reported in this study for its unusual site, very large size, and peculiar morphology.