بایگانی برچسب برای: Peripheral

Peripheral.Artery.Disease.Second.[taliem.ir]

Peripheral Artery Disease

Peripheral artery disease (PAD) is unfortunately infrequently recognized. The treatment of PAD continues to evolve but is fundamentally focused on control of risk factors in order to prevent the associated risk of heart attack, stroke, and premature cardiovascular death as well as improvement in exercise performance and limb preservation. The pathophysiology of progressive atherosclerotic plaque in the extremities is thought to involve plaque hemorrhage and rupture, but few data support this presumption. Clinical research is needed to develop agents designed to halt progression of atherosclerotic disease in the peripheral arterial system. Despite these current limitations in understanding and treating PAD, new lipid modifying agents and new antiplatelet treatment of risk factors and strategies to improve pain‐free walking distance have emerged, including the use of emerging endovascular strategies. In addition, with the rapid evolution of technology to improve arterial perfusion with minimally invasive catheter‐based strategies, options for revascularization of patients with advanced symptoms and signs of PAD are improving.
Modern.Concepts.of.Peripheral.Nerve.Repair.[taliem.ir]

Modern Concepts of Peripheral Nerve Repair

Peripheral nerves arise from the spinal cord, and they contain axons from different types of neurons serving various effector organs or sensory endings. The cell bodies of motor neurons that innervate skeletal muscle fbres are situated in the anterior horns of the grey matter of the spinal cord. Enlargements of the cord in the cervical and lumbar segments mark the major regions supplying the upper and lower limbs (Fig. 1.1). The frst sensory neurons are situated in the dorsal root ganglia, which are located in the intervertebral foramina, just proximal to the fusion of the anterior and posterior roots. The peripheral nerve is composed of motor, sensory and sympathetic nerve fbres. A nerve fbre is the conducting unit of the nerve and contains the following elements: a central core, the axon and Schwann cells. Some nerve fbres are surrounded by a myelin component (myelinated nerve fbres), and others are free of such myelin sheath (unmyelinated nerve fbres) .
Peripheral.Ulcerative.Keratitis.[taliem.ir]

Peripheral Ulcerative Keratitis

Cornea is a transparent area which makes one-sixth of the outer circumference of the eye. At the periphery is a transition zone 1– 1.5 mm, limbus where corneal stroma is bonded to the sclera. The adult cornea is 10.5 mm vertically and 11.5 mm horizontally. The anterior and posterior surfaces are parallel to each other in the central 4 mm spherical-shaped “optical zone” where the cornea averages 0.52 mm in thickness. The peripheral cornea is slightly flattened, anterior and posterior surfaces are no longer parallel and corneal thickness increases to 0.65 mm. Even though central cornea is responsible for the formation of sharp retinal image as it lies in the visual axis, studies have proven that peripheral cornea also has significant role in affecting the optical quality of the image formed.