A novel cumulative level difference mean based GLDM and modified ABCD features ranked using eigenvector centrality approach for four skin lesion types classification

BACKGROUND AND OBJECTIVE

Melanoma is one of the major death causes while basal cell carcinoma (BCC) is the utmost incident skin lesion type. At their early stages, medical experts may be confused between both types with benign nevus and pigmented benign keratoses (BKL). This inspired the current study to develop an accurate automated, user-friendly skin lesion identification system.

METHODS

The current work targets a novel discrimination technique of four pre-mentioned skin lesion classes. A novel proposed texture feature, named cumulative level-difference mean (CLDM) based on the gray-level difference method (GLDM) is extracted. The asymmetry, border irregularity, color variation and diameter are summed up as the ABCD rule feature vector is originally used to classify the melanoma from benign lesions. The proposed method improved the ABCD rule to also classify BCC and BKL by using the proposed modified-ABCD feature vector. In the modified set of ABCD features, each border feature, such as compact index, fractal dimension, and edge abruptness is considered a separate feature. Then, the composite feature vector having the pre-mentioned features is ranked using the Eigenvector Centrality (ECFS) feature ranking method. The ranked features are then classified by a cubic support vector machine for different numbers of selected features.

RESULTS

The proposed CLDM texture features combined with the ranked ABCD features achieved outstanding performance to classify the four targeted classes (melanoma, BCC, nevi and BKL). The results report 100% outstanding performance of the sensitivity, accuracy and specificity per each class compared to other features when using the highest seven ranked features.

CONCLUSIONS

The proposed system established that Melanoma, BCC, nevus and BKL are efficiently classified using cubic SVM with the new feature set. In addition, the comparative studies proved the superiority of the cubic SVM to classify the four classes.

Reactive keratoma of the central corneal epithelium

PURPOSE

The authors present a unique corneal tumor.

METHODS

A 75-year-old gardener presented with a 1-year history of a slowly growing central corneal lesion with progressive visual loss. We performed an ophthalmic examination, slit lamp photography, high-frequency ultrasonography, and culture with sensitivity (followed by therapeutic scrape biopsy).

RESULTS

Clinical examination revealed a gray-white central corneal tumor without extension to the limbus. No significant tumor neovascularization or intraocular inflammation was noted. High frequency ultrasound revealed no penetration of the corneal stroma. The tumor was removed with a platinum spatula. Histopathology revealed simple hyperkeratosis characterized by stratified hyperkeratotic corneal epithelium with metaplastic granular layer characteristic of epidermis. Few and focal clusters of passenger bacteria were found (as seen in cutaneous leukoplakia). Cultures revealed a few Gram-positive cocci and no fungus. A human papilloma virus wide-screen spectrum assay (in situ hybridization) was negative.

CONCLUSIONS

The authors present a benign keratoma of the central corneal epithelium. High frequency ultrasound and scrape biopsy histopathologic techniques were used to diagnose and treat this keratoleukoma caused by a reactive keratoma as well as improve his vision.

Diagnosis of nonmelanoma skin cancer/keratinocyte carcinoma: a review of diagnostic accuracy of nonmelanoma skin cancer diagnostic tests and technologies

BACKGROUND

Nonmelanoma skin cancer (NMSC) is the most prevalent cancer in the light-skinned population. Noninvasive treatment is increasingly used for NMSC patients with superficial lesions, making the development of noninvasive diagnostic technologies highly relevant.

OBJECTIVE

The scope of this review is to present data on the current state-of-the-art diagnostic methods for keratinocyte carcinoma: basal cell carcinoma, squamous cell carcinoma, and actinic keratosis.

METHODS AND MATERIALS

MEDLINE, BIOSIS, and EMBASE searches on NMSC and physical and clinical examination, biopsy, molecular marker, ultrasonography, Doppler, optical coherence tomography, dermoscopy, spectroscopy, fluorescence imaging, confocal microscopy, positron emission tomography, computed tomography, magnetic resonance imaging, terahertz imaging, electrical impedance and sensitivity, specificity, and diagnostic accuracy.

RESULTS

State-of-the-art diagnostic research has been limited in this field, but encouraging results from the reviewed diagnostic trials have suggested a high diagnostic accuracy for many of the technologies. Most of the studies, however, were pilot or small studies and the results would need to be validated in larger trials.

CONCLUSIONS

Some of these new imaging technologies have the capability of providing new, three-dimensional in vivo, in situ understanding of NMSC development over time. Some of the new technologies described here have the potential to make it from the bench to the clinic.

Keratoameloblastoma: a tumor sui generis or a chimera?

The term keratoameloblastoma has been used to describe a histologically heterogeneous group of ameloblastoma variants which have in common the formation of keratin by the ameloblastomatous epithelium. The English language literature contains reports of only 12 cases of keratoameloblastoma, of which 4 cases exhibited a papilliferous component. We report a unique tumor that we believe falls within the broad histopathologic spectrum of keratoameloblastoma. We review the key clinical and histopathologic features of the previously reported cases of keratoameloblastoma and present an additional case that presented as an expansile, radiolucent lesion with internal opacification between the roots of teeth in the left anterior maxillary alveolar ridge of a 45-year-old white male. There is wide variation in the histopathologic appearance of cases reported under the appellation keratoameloblastoma. Our case exhibited a histopathologic feature shared by only 2 of the previously reported cases, notably islands and anastomosing cords of epithelium forming lamellated, pacinian-like stacks of parakeratin that extruded into the collagenous tumor stroma without eliciting a foreign body response. Due to the small number of reported cases, we are unable to accurately assess whether the biologic behavior of keratoameloblastoma differs from other histologic types of ameloblastoma.

L’échographie cutanée haute résolution : utilité pour le diagnostic, le traitement et la surveillance des maladies dermatologiques

Although less precise than histological examination, high-resolution skin imaging is a noninvasive technique that provides complementary information to the clinical examination: the lesion's US structure as well as its lateral and depth extension. Ultrasonography helps in diagnosis and initial management by measuring melanoma thickness (so as to remove this lesion with safety margins) before destructive treatment (cryosurgery or radiotherapy), by showing tumor limits, or by detecting subclinical recurrence during the follow-up. In this paper, ultrasound images will be correlated with clinical and histological data in various clinical situations such as tumors, edema, cutaneous infiltration, sclerous tissues, hyperlaxity, and cutaneous aging.

Complications of keratosis obturans

Three patients with extensive keratosis obturans were treated during a 12-month period. One presented with an idiopathic sensorineural hearing loss and was found to have keratosis obturans in the contralateral, asymptomatic ear. The disease process had resulted in a horizontal semicircular canal fistula in what was now, effectively, the only hearing ear. The second patient had an extensive dehiscence of the tegmen tympani. The third presented with a facial palsy. An automastoidectomy cavity was present, with circumferential skeletonization of the descending facial nerve over a length of 1.5 cm and dehiscence of the temporomandibular joint and jugular bulb. All three patients were successfully treated by surgical formalization of their automastoidectomy cavities. They appeared to represent cases of keratosis obturans rather than external auditory canal cholesteatoma, on the basis of previously published reports.

These complications and patterns of bone erosion have not previously been described in keratosis obturans. The third patient is believed to have the most extensive case of keratosis obturans yet described.

Neglected keratosis obturans causing facial nerve palsy

Keratosis obturans is characterized by the accumulation of desquamated keratinous material in the bony portion of the external auditory canal. Classically, it is reported to present with severe otalgia, conductive hearing loss and global widening of the external auditory canal. Extensive erosion of the bony meatus, with exposure of the facial nerve, has been previously reported, but no case of facial nerve palsy has as yet been published. We report the first published case, to our knowledge, of a unilateral facial nerve palsy secondary to neglected keratosis obturans.

Complete and partial hoof wall resection for keratoma removal: post operative complications and final outcome in 26 horses (1994-2004)

REASONS FOR PERFORMING STUDY

There are no data on the frequency of post operative complications following keratoma removal, such as recurrence, hoof wall instability and excessive granulation tissue formation, or their relation to the method of surgical removal.

OBJECTIVE

To identify important factors in the outcome for horses undergoing surgical removal of a keratoma and compare the post operative complications encountered following keratoma removal by complete hoof wall resection (CR) and partial hoof wall resection (PR).

HYPOTHESIS

Horses undergoing PR would have fewer post operative complications and would return to work more quickly than those undergoing CR.

METHODS

A retrospective review of medical records from one equine hospital identified 26 horses that underwent removal of a keratoma by CR or PR. Clinical, radiological and surgical findings and outcome were analysed.

RESULTS

Common clinical signs included lameness and the presence of a subsolar abscess. Fourteen horses underwent CR and 12 PR. The complication rate following CR (71%) was significantly lower than that following PR (25%) (P<0.01). Complications encountered included excess granulation tissue formation, hoof crack formation and keratoma recurrence at the surgical site. The time taken to return to full work post operatively was significantly shorter in horses undergoing PR compared to CR (P<0.01). All horses, except one, returned to their previous exercise level.

CONCLUSIONS

PR resulted in fewer post operative complications and a more rapid return to athletic activity than CR.

POTENTIAL RELEVANCE

Although the overall complication rate for CR was higher than for PR, the overall prognosis for return to soundness and the previous performance level is very good.

Inhibition of the TNF-pathway: use of infliximab and etanercept as remission-inducing agents in cases of therapy-resistant chronic inflammatory disorders

OBJECTIVE

To examine the potential of the two tumour necrosis factor (TNF) inhibitors infliximab and etanercept as remission-inducing agents in chronic therapy-resistant inflammatory disorders of immune or non-immune pathogenesis.

METHODS

14 patients with adult Still's disease/macrophage activation syndrome (4), Wegener's disease (3), Behçet's disease (3), keratoscleritis (1), lymphomatous tracheo-bronchitis (1) Cogan's syndrome (1), and rapidly destructive crystal arthropathy (1) were treated with infliximab (n = 10) and etanercept (n = 4). All patients showed organ-threatening progression of their diseases with resistance to conventional immunosuppressive medication. Therapeutic benefit was assessed clinically and by documenting organ-specific functional and morphological alterations. Side effects were compared with the data of our clinic's rheumatoid arthritis (RA) patients treated by TNF inhibitors.

RESULTS

A rapid and dramatic beneficial effect was documented in 9 patients and a moderate one in 5. Best responses (clinical and laboratory parameters) were seen in patients with macrophage activation syndrome/adult Still's disease and Behçet's disease, while the results were less impressive in those with Wegener's disease, Cogan's syndrome, idiopathic cerato-scleritis and lymphomatous tracheobronchitis. In all cases immunosuppressive agents and systemic glucocorticoids could be reduced or discontinued.

CONCLUSIONS

TNF inhibition may be highly effective in patients with severe, therapy-resistant chronic inflammatory disorders.

[On keratomas on the frontal sinus]

Etiopathogenesis of the frontal sinus kertomas has been discussed paying a special attention to the frequency of its occurrence reported in literature. Authors present a rare complication of frontal sinus keratoma involving a bone destruction of nearby lying structures.

Lesser metatarsal V-osteotomy for chronic intractable plantar keratosis. Retrospective analysis of 40 procedures

The authors studied 40 V-osteotomies of the lesser metatarsal performed for chronic intractable plantar keratosis. They discuss the effectiveness of the V-osteotomy for this deformity as well as other findings such as whether or not fixation of the osteotomy yields a better result (i.e., a lower incidence of complications). The results show that the V-osteotomy had limited effectiveness for this condition and resulted in a high complication rate.

Imaging of the skin with 20-MHz US

PURPOSE

The authors clinically evaluated a new high-frequency ultrasound (US) scanner to determine the value of US for dermatologic applications.

MATERIALS AND METHODS

A 20-MHz US scanner was used to visualize normal skin at eight sites in 10 healthy volunteers and to evaluate 200 skin lesions (45 malignant, 155 benign).

RESULTS

In normal skin, the dermis was markedly echogenic and sharply demarcated from hypoechoic subcutaneous fat. The epidermis was not resolved except on the palm and sole. Only three superficial lesions were not identified with US; evaluation of another three was limited by shadowing. Thickness of the lesions visualized was 0.2-26.0 mm (mean, 1.9 mm +/- 2.6). Most lesions (77%) were hypoechoic, 9% were anechoic, 12% had mixed echogenicity, and 2% were isoechoic or hyperechoic.

CONCLUSION

The diagnostic role of high-frequency US appears limited. It did not help differentiate benign from malignant lesions, but it did enable accurate delineation of deep margins of lesions and allowed noninvasive measurement of thickness. These features may help in the preoperative evaluation of skin tumors and in monitoring the response to therapy for certain inflammatory conditions.

Ultrasonographic imaging of a keratoma in a horse

Ultrasonography was used to confirm the tentative diagnosis of keratoma in a horse admitted for chronic progressive lameness. A definitive diagnosis of keratoma traditionally has been diagnosed by history, clinical findings, and radiographic evaluation. Confirmation of the keratoma by use of ultrasonography facilitated the formulation of a treatment plan that resolved the condition.

Automastoidectomy caused by keratosis obturans: a case report

This is a case report of a 25-year-old Oriental woman with persistent and neglected keratosis obturans. The enlarging plug of keratin in the deep meatus produced an "automastoidectomy" in the left ear. The clinical findings are supplemented with a preoperative CT scan, and by pre- and postoperative Hopkins rod photographs of the ear. This case demonstrates dramatically the extensive erosion of bone that can occur in a patient with neglected keratosis obturans.

A radiologic sign of epidermolytic hyperkeratosis

The radiologic finding of innumerable fine ridges in the outer soft tissues of a patient with severe generalized epidermolytic hyperkeratosis is presented as a sign of the disease. The radiodensity results from the density of keratin and low water content in the scales of epidermolytic hyperkeratosis.

Tomography of the petrous bone in keratosis obturans

Three cases of keratosis obturans, which were studied by tomography of the petrous temporal bone, are described. The widening of the deep bony part of the external auditory canal by pressure erosion of an impacted benign slowly-growing mass is the key radiological finding. Erosion was so severe as to involve the facial nerve canal in one and the temporo-madibular joint in two cases. The theories of causation are reviewed. Tomography using elliptical tube movement was valuable in diagnosis, pre- and post-operative management.