ABSTRACT
An optical system for multichannel coupling of laser arrays to polymer waveguide array probes with a single biconvex lens is developed. The developed cylindrical module with 13 mm and 20 mm in diameter and length, respectively, enables coupling of eight individual optical channels using an aspheric lens. Specific coupling with crosstalk below -13d B for each channel and quasi-uniform coupling over all channels is achieved for a waveguide array with 100 µm lateral facet pitch at the incoupling site. The polymer waveguide technology allows for tapering of the lateral waveguide pitch to 25 µm toward the tip of the flexible waveguide array. SU-8 and PMMA are used as the waveguide core and cladding, respectively. The optical coupling module is designed as a prototype for preclinical evaluation of optical neural stimulators.
ABSTRACT
Summary. Melorheostosis is a sclerosing disease commonly affecting the bone, rarely soft tissue. Etiology is unknown. It causes uncharacteristic symptoms such as pain, joint stiffness, soft tissue contractures, and limb deformities. Standard radiology reveals the diagnosis. Until now there is no standard therapy. Melorheostosis is a rare bone dysplasia and important as a differential diagnosis for tumorous changes in the limb or in painful joints.
Subject(s)
Bone and Bones/diagnostic imaging , Hand/diagnostic imaging , Melorheostosis/diagnostic imaging , Adolescent , Diagnosis, Differential , Female , Genes, Recessive , Humans , Melorheostosis/genetics , Tomography, X-Ray ComputedABSTRACT
BACKGROUND: The substance cantharidin, which is produced by a type of beetle, rapidly penetrates the epidermis and can cause severe toxicities such as skin necrosis. Optimal treatment for necrotic beetle bites has not been well defined. Conservative management has been advocated but the hospital stays are long and long-term morbidity may result, especially in multimorbid patients. OBJECTIVE: The value of aggressive surgical management of such necrotizing diseases using newly developed surgical tools is compared to the traditional more conservative approach. RESULTS: We present the case of a multimorbid 60-year-old man with a rapidly progressive necrosis of the medial thigh (measuring 30 X 15 cm), acquired during a stay in Western Africa after being bitten by a beetle of the species Cantharide. The patient was treated with radical surgical debridement and continuous elimination of the wound fluid by permanent computer-controlled negative pressure with a vacuum-assisted wound-closure device. This led to the sudden relief of both local and systemic symptoms and allowed extremely early wound closure. CONCLUSIONS: Comparing literature data with the course of this combined treatment, we strongly suggest an early aggressive management with complete radical excision of necrotic tissue, conditioning of the wound bed by temporary suction-assisted vacuum closure and subsequent skin grafting with continued vacuum application. This treatment leads to immediate relief of pain and enhanced healing of this lesion even in the condition of immunosuppression in the elderly.