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This video depicts tracheostomy being performed. This procedure bypasses the normal air passage and creates a direct passage into the trachea just below the voice box. This is a life saving procedure in patients who have respiratory obstruction above the level of vocal cords
McMurray's maneuver is used to detect the presence of meniscal tears. To detect a medial meniscal injury, the patient is put in a supine position with the knee in maximum flexion. One hand of the examiner is placed on the posteromedial margin of the involved knee and the other hand supports the foot. The tibia is then externally rotated, and the knee is extended slowly. The test is positive if there is an audible or palpable click or popping sensation during extension of the involved knee.
The complex circuitry interconnecting different areas in the brain, known collectively as white matter, is composed of millions of axons organized into fascicles and bundles. Upon macroscopic examination of sections of the brain, it is difficult to discern the orientation of the fibers. The same is true for conventional imaging modalities. However, recent advancements in magnetic resonance imaging (MRI) make such task possible in a live subject. By sensitizing an otherwise typical MRI sequence to the diffusion of water molecules it is possible to measure their diffusion coefficient in a given direction1. Normally, the axonal membrane and myelin sheaths pose barriers to the movement of water molecules and, thus, they diffuse preferentially along the axon2. Therefore, the direction of white matter bundles can be elucidated by determining the principal diffusivity of water. The three-dimensional representation of the diffusion coefficient can be given by a tensor and its mathematical decomposition provides the direction of the tracts3; this MRI technique is known as diffusion tensor imaging (DTI). By connecting the information acquired with DTI, three-dimensional depictions of white matter fascicles are obtained4. The virtual dissection of white matter bundles is rapidly becoming a valuable tool in clinical research.
Our journey begins with a transverse section of tightly packed axons as seen through light microscopy. Although represented as a two-dimensional "slice", we see that these axons in fact resemble tubes. A simulation of water molecules diffusing randomly inside the axons demonstrates how the membranes and myelin hinder their movement across them and shows the preferred diffusion direction --along the axons. The tracts depicted through DTI slowly blend in and we ride along with them. As we zoom out even more, we realize that it is a portion of the corpus callosum connecting the two sides of the brain we were traveling on and the great difference in relative scale of the individual axons becomes evident. The surface of the brain is then shown, as well as the rest of the white matter bundles--a big, apparently chaotic tangle of wires. Finally, the skin covers the brain.
With the exception of the simulated water molecules, all the data presented in the animation is obtained through microscopy and MRI. Computer algorithms for the extraction of the cerebral structures and a custom-built graphics engine make our journey through the brain's anatomy possible in a living person.
Micrograph courtesy of Dr. Christian Beaulieu, University of Alberta.
Music by Mario Mattioli.
References:
1. Stejskal, E.O., et al., J. Chem. Phys., 1965. 42:
2. Beaulieu, C., NMR Biomed., 2002. 15:435-55.
3. Basser, P.J., et al., J. Magn. Reson. B, 1994. 103:247-54.
4. Mori, S., et al., NMR Biomed., 2002. 15:468-80.
Hirschsprung's (HIRSH-sproongz) disease is a condition that affects the large intestine (colon) and causes problems with passing stool. The condition is present at birth (congenital) as a result of missing nerve cells in the muscles of the baby's colon. A newborn who has Hirschsprung's disease usually can't have a bowel movement in the days after birth. In mild cases, the condition might not be detected until later in childhood. Uncommonly, Hirschsprung's disease is first diagnosed in adults.
arteriovenous hemodialysis access has been the "gold standard" for patients needing hemodialysis for the past 30 years. Despite the reported advantages of autologous access, the availability of prosthetic graft material, coupled with the challenging dialysis candidate, has led to a trend of primary prosthetic graft dialysis access in the 1980s and 1990s. In recognition of this unfortunate trend, the National Kidney Foundation Dialysis Outcomes Quality Initiative (DOQI) used evidence from published studies and summary articles to generate clinical practice guidelines, emphasizing a shift back to autologous arteriovenous fistula (AVF) as the key to long-term successful hemodialysis.[1,2] These initial guidelines proposed a goal of 50% autologous AVF as the initial access, with a 40% prevalence of autologous access for a given practice or unit.
The video is about the evolution of the anatomic UCLA laparoscopic technique over 1325 cases and demonstrates the key steps of our operation to improve patient safety and outcomes.
Learn more at http://urology.ucla.edu
ICDs are useful in preventing sudden death in patients with known, sustained ventricular tachycardia or fibrillation. Studies have shown ICDs to have a role in preventing cardiac arrest in high-risk patients who haven't had, but are at risk for, life-threatening ventricular arrhythmias. View an animation of an ICD. Newer-generation ICDs may have a dual function which includes the ability to serve as a pacemaker. The pacemaker feature would stimulate the heart to beat if the heart rate is detected to be too slow. What is an Implantable Cardioverter Defibrillator (ICD)? An ICD is a battery-powered device placed under the skin that keeps track of your heart rate. Thin wires connect the ICD to your heart. If an abnormal heart rhythm is detected the device will deliver an electric shock to restore a normal heartbeat if your heart is beating chaotically and much too fast. ICDs have been very useful in preventing sudden death in patients with known, sustained ventricular tachycardia or fibrillation. Studies have shown that they may have a role in preventing cardiac arrest in high-risk patients who haven't had, but are at risk for, life-threatening ventricular arrhythmias.
Ettore Vulcano, MD, Foot and Ankle Orthopedic Surgeon at Mount Sinai West, discusses a new minimally invasive bunion surgery that has patients walking immediately after surgery, and getting back to an active lifestyle much quicker than with the traditional surgery.
Polyarteritis nodosa Email this page to a friend Email this page to a friend Facebook Twitter Google+ Polyarteritis nodosa is a serious blood vessel disease. The small and medium-sized arteries become swollen and damaged. Causes Arteries are the blood vessels that carry oxygen-rich blood to organs and tissues. The cause of polyarteritis nodosa is unknown. The condition occurs when certain immune cells attack the affected arteries. More adults than children get this disease. The tissues that are fed by the affected arteries do not get the oxygen and nourishment they need. Damage occurs as a result. People with active hepatitis B or hepatitis C may develop this disease.
Dr. Ed Tingstad, Orthopedic Surgeon with Pullman Regional Hospital’s Orthopedic Center of Excellence and Inland Orthopaedic Surgery & Sports Medicine Clinic performs a total knee replacement using orthopedic robotics – VELYS. The VELYS Robotic-Assisted Solution technology makes for a more exact fitting knee replacement and uses intra-operative data to inform the surgeon during surgery. In this full-length total knee replacement video, Dr. Tingstad narrates a procedure from start to finish.
Learn more: pullmanregional.org/orthopedics
Multiple sclerosis (MS) is a disease of the central nervous system estimated to affect 2.3 million people worldwide. It is a chronic disease in which the immune system abnormally attacks the insulation and support around the nerve cells (myelin sheath) in the brain, spinal cord and optic nerves, causing inflammation and consequent damage. MS is a leading cause of non-traumatic disability in young people, usually striking between 20 and 40 years of age. There is no cure for MS, but research continues to better understand and treat the disease.
The human brain is the command center for the human nervous system. It receives input from the sensory organs and sends output to the muscles. The human brain has the same basic structure as other mammal brains, but is larger in relation to body size than any other brains.
Electronystagmography (ENG) is a diagnostic test to record involuntary movements of the eye caused by a condition known as nystagmus. It can also be used to diagnose the cause of vertigo, dizziness or balance dysfunction by testing the vestibular system.
his patient had spilled boiling water on his lower leg a couple days before. This isn't complicated but the teaching points should focus on draining the large blistered areas and attempting to maintain moisture as long as we can so the skin doesn't contract down on itself.
atrial septal defect (ASD) is a hole in the wall between the two upper chambers of your heart (atria). The condition is present from birth (congenital). Small atrial septal defects may close on their own during infancy or early childhood. Large and long-standing atrial septal defects can damage your heart and lungs. Small defects may never cause a problem and may be found incidentally. An adult who has had an undetected atrial septal defect for decades may have a shortened life span from heart failure or high blood pressure that affects the arteries in the lungs (pulmonary hypertension). Surgery may be necessary to repair atrial septal defects to prevent complications