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Function and Anatomy:
Hinge type joint formed by the articulation of the Ulna and Radius (bones of the forearm), and Humerus (upper arm). Full extension is equal to 0 degrees, full flexion to ~ 150 degrees. Maximum supination (turning hand palm up so that it can hold a bowl of "soup") and pronation (palm down) are both 90 degrees
The exam should be performed in an orderly fashion as follows: 1. Have the patient stick out their tongue so that you can examine the posterior pharynx (i.e. the back of the throat). Ask the patient to say "Ah", which elevates the soft palate, giving you a better view. If you are still unable to see, place the tongue blade � way back on the tongue and press down while the patient again says "Ah," hopefully improving your view. This causes some people to gag, particularly when the blade is pushed onto the more proximal aspects of the tongue. It may occasionally be important to determine whether the gag reflex is functional (e.g. after a stroke that impairs CNs 9 or 10; or to determine if a patient with depressed level of consciousness is able to protect their airway from aspiration). This is done by touching a q-tip against the posterior pharynx, uvula or tongue. It is not necessary to do this during your routine exam as it can be quite noxious!
2. Note that the uvula hangs down from the roof of the mouth, directly in the mid-line. With an "Ah," the uvula rises up. Deviation to one side may be caused by CN 9 palsy (the uvula deviates away from the affected side), a tumor or an infection. CN9 Pasly Cranial Nerve 9 Dysfunction: Patient has suffered stroke, causing loss of function of left CN 9. As a result, uvula is pulled towards the normally functioning (ie right) side. 3. The normal pharynx has a dull red color. In the setting of infection, it can become quite red, frequently covered with a yellow or white exudate (e.g. with Strep. Throat or other types of pharyngitis).
4. The tonsils lie in an alcove created by arches on either side of the mouth. The apex of these arches are located lateral to and on a line with the uvula. Normal tonsils range from barely apparent to quite prominent. When infected, they become red, are frequently covered by whitish/yellow discharge. In the setting of a peritonsilar abscess, the tonsils appear asymmetric and the uvula may be pushed away from the affected side. When this occurs, the tonsil may actually compromise the size of the oral cavity, making breathing quite difficult.
5. Look carefully along the upper and lower gum lines and at the mucosa in general, which can appear quite dry if the patient is dehydrated.
6. Examine the teeth to get a sense of general dentition, particularly if the patient has a dental complaint. Pain produced by tapping on a tooth is commonly caused by a root abscess. Tooth Abscess: Tooth abscess involving left molar region. Associated inflammation of left face can clearly be seen. 7. Have the patient stick their tongue outside their mouth, which allows evaluation of CN 12. If there is nerve impairment, the tongue will deviate towards the affected side. Any obvious growths or abnormalities? Ask them to flip their tongue up so that you can look at the underside. If you see something abnormal, grasp the tongue with gauze so that you can get a better look. Left CN 12 Dysfunction: Stroke has resulted in L CN 12 Palsy. Tongue therefore deviates to the left.
8. Make note of any growths along the cheeks, hard palate (the roof of the mouth between the teeth), soft palate, or anywhere else. In particular, patients who smoke or chew tobacco are at risk for oral squamous cell cancer. Any areas which are painful or appear abnormal should also be palpated. Put on a pair of gloves to better explore these regions. What do they feel like? Are they hard? To what extent does a growth involve deeper structures? If the patient feels something that you cannot see, try to get someone else to hold the light source, freeing both your hands to explore the oral cavity with two tongue depressors.
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.
ENDOSCOPIC (NON-SURGICAL) REMOVAL OF MULTIPLE LARGE TUMORS FROM STOMACH IN A PATIENT WITH PEUTZ-JEGHERS SYNDROME
PEUTZ-JEGHERS SYNDROME: Peutz-Jeghers syndrome (PJS) is a familial syndrome consisting of mucocutaneous pigmentation, gastrointestinal polyposis and cancers of gut & other sites like breast, ovary, and testes. PJS has an autosomal dominant inheritance with variable and incomplete penetrance. Germline mutations of STK11/LKB1 gene on 19p cause this syndrome. Mucocutaneous pigmentation may be noted in early infancy. These deposits of melanin are most commonly found around the mouth, nose, lips, buccal mucosa, hands, and feet, and may also be present in perianal and genital areas. PJS polyps may be found in stomach, small intestine, or colon, but they tend to be prominent in the small intestine. These polyps may increase in size and cause small intestinal obstruction or intussusceptions that may occur in early infancy. Acute upper gastrointestinal bleeding and chronic faecal blood may complicate the disease.
PATIENT: The patient was a 25 yr male who had mucocutaneous pigmentation and multiple polyps in the stomach and duodenum. He presented with bleeding from gastric polyps. As the polyps in stomach were numerous, (more than 20 in number) and were large in size (some equal to small egg size), he had been advised to undergo surgery. Surgery planned was total gastrectomy.
PROCEDURE: The patient underwent video-endoscopy of the esophagus, stomach and duodenum. All polyps were examined for size and presence or absence of stalk. A plan to remove all the gastric polyps at endoscopy was made in the same sitting. He received light conscious sedation. Flat polyps were raised form the gastric wall by injection of saline in to polyp base to let these lesions have a stalk. This was done by needle injector. Each polyp was engaged in a snare and the polyp stalk was cut by coagulation cutting current. The cuts were clean without any bleeding. All polyps were recovered for histology. The histology revealed all polyps to be hamartomous lesions. None of the polyps were cancerous. Patient has been followed up for over one year and is doing fine without any further bleeding or pain.
Video shows the procedure of videoendoscpy and endoscopic removal of polyps.
Patient Greg Grindley communicates with host Bryant Gumbel and his wife for the first time while undergoing deep brain stimulation surgery at University Hospital's Case Medical Center in Cleveland, Ohio.
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Greg's First In-Surgery Conversation | Brain Surgery Live
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To facilitate the delivery of fluids during labour, obstetric anaesthetists from Coventry designed a triple IV peripheral connector with a central high-flow anti-reflux valve. This connector, now rightly known as the Coventry valve, can be used for all theatre settings and is especially useful in obstetrics, ICU, HDU and orthopaedics. More details on www.mediplus.co.uk