Medical School

Apr 15

Nutcracker syndrome (NCS) results most commonly from the compression of the left renal vein between the abdominal aorta (AA) and superior mesenteric artery (SMA), although other variants exist. The name derives from the fact that, in the sagittal plane and/or transverse plane, the SMA and AA (with some imagination) appear to be a nutcracker crushing a nut (the renal vein). There is a wide spectrum of clinical presentations and diagnostic criteria are not well defined, which frequently results in delayed or incorrect diagnosis.This condition is not to be confused with superior mesenteric artery syndrome, which is the compression of the third portion of the duodenum by the SMA and the AA.

Nutcracker syndrome (NCS) results most commonly from the compression of the left renal vein between the abdominal aorta (AA) and superior mesenteric artery (SMA), although other variants exist. The name derives from the fact that, in the sagittal plane and/or transverse plane, the SMA and AA (with some imagination) appear to be a nutcracker crushing a nut (the renal vein). There is a wide spectrum of clinical presentations and diagnostic criteria are not well defined, which frequently results in delayed or incorrect diagnosis.This condition is not to be confused with superior mesenteric artery syndrome, which is the compression of the third portion of the duodenum by the SMA and the AA.

(Source: Wikipedia)

Apr 13

This early stethoscope belonged to Laennec (Science Museum, London)
The stethoscope was invented in France in 1816 by René Laennec at the Necker-Enfants Malades Hospital in Paris. It consisted of a wooden tube and was monaural. His device was similar to the common ear trumpet, a historical form of hearing aid; indeed, his invention was almost indistinguishable in structure and function from the trumpet, which was commonly called a “microphone”.
The first flexible stethoscope of any sort may have been a binaural instrument with articulated joints not very clearly described in 1829.In 1840, Golding Bird described a stethoscope he had been using with a flexible tube. Bird was the first to publish a description of such a stethoscope but he noted in his paper the prior existence of an earlier design (which he thought was of little utility) which he described as the snake ear trumpet. Bird’s stethoscope had a single earpiece. In 1851, Irish physician Arthur Leared invented a binaural stethoscope, and in 1852 George Cammann perfected the design of the instrument for commercial production, which has become the standard ever since. Cammann also wrote a major treatise on diagnosis by auscultation, which the refined binaural stethoscope made possible. By 1873, there were descriptions of a differential stethoscope that could connect to slightly different locations to create a slight stereo effect, though this did not become a standard tool in clinical practice. Rappaport and Sprague designed a new stethoscope in the 1940s, which became the standard by which other stethoscopes are measured, consisting of two sides, one of which is used for the respiratory system, the other for the cardiovascular system. The Rappaport-Sprague was later made by Hewlett-Packard. HP’s medical products division was spun off as part of Agilent Technologies, Inc., where it became Agilent Healthcare. Agilent Healthcare was purchased by Philips which became Philips Medical Systems, before the walnut-boxed, $300, original Rappaport-Sprague stethoscope was finally abandoned ca. 2004, along with Philips’ brand (manufactured by Andromed, of Montreal, Canada) electronic stethoscope model. The Rappaport-Sprague model stethoscope was heavy and short (18–24 in (46–61 cm)) with an antiquated appearance recognizable by their two large independent latex rubber tubes connecting an exposed-leaf-spring-joined-pair of opposing “f”-shaped chrome-plated brass binaural ear tubes with a dual-head chest piece. Several other minor refinements were made to stethoscopes, until in the early 1960s Dr. David Littmann, a Harvard Medical School professor, created a new stethoscope that was lighter than previous models and had improved acoustics. The Littmann stethoscope is the model used by most medical students today.

This early stethoscope belonged to Laennec (Science Museum, London)

The stethoscope was invented in France in 1816 by René Laennec at the Necker-Enfants Malades Hospital in Paris. It consisted of a wooden tube and was monaural. His device was similar to the common ear trumpet, a historical form of hearing aid; indeed, his invention was almost indistinguishable in structure and function from the trumpet, which was commonly called a “microphone”.

The first flexible stethoscope of any sort may have been a binaural instrument with articulated joints not very clearly described in 1829.In 1840, Golding Bird described a stethoscope he had been using with a flexible tube. Bird was the first to publish a description of such a stethoscope but he noted in his paper the prior existence of an earlier design (which he thought was of little utility) which he described as the snake ear trumpet. Bird’s stethoscope had a single earpiece. In 1851, Irish physician Arthur Leared invented a binaural stethoscope, and in 1852 George Cammann perfected the design of the instrument for commercial production, which has become the standard ever since. Cammann also wrote a major treatise on diagnosis by auscultation, which the refined binaural stethoscope made possible. By 1873, there were descriptions of a differential stethoscope that could connect to slightly different locations to create a slight stereo effect, though this did not become a standard tool in clinical practice. Rappaport and Sprague designed a new stethoscope in the 1940s, which became the standard by which other stethoscopes are measured, consisting of two sides, one of which is used for the respiratory system, the other for the cardiovascular system. The Rappaport-Sprague was later made by Hewlett-Packard. HP’s medical products division was spun off as part of Agilent Technologies, Inc., where it became Agilent Healthcare. Agilent Healthcare was purchased by Philips which became Philips Medical Systems, before the walnut-boxed, $300, original Rappaport-Sprague stethoscope was finally abandoned ca. 2004, along with Philips’ brand (manufactured by Andromed, of Montreal, Canada) electronic stethoscope model. The Rappaport-Sprague model stethoscope was heavy and short (18–24 in (46–61 cm)) with an antiquated appearance recognizable by their two large independent latex rubber tubes connecting an exposed-leaf-spring-joined-pair of opposing “f”-shaped chrome-plated brass binaural ear tubes with a dual-head chest piece. Several other minor refinements were made to stethoscopes, until in the early 1960s Dr. David Littmann, a Harvard Medical School professor, created a new stethoscope that was lighter than previous models and had improved acoustics. The Littmann stethoscope is the model used by most medical students today.

(Source: Wikipedia)

Apr 12

Veins are blood vessels that carry blood toward the heart. Most veins carry deoxygenated blood from the tissues back to the heart; exceptions are the pulmonary and umbilical veins, both of which carry oxygenated blood to the heart. Veins differ from arteries in structure and function; for example, arteries are more muscular than veins, veins are often closer to the skin and contain valves to help keep blood flowing toward the heart, while arteries carry blood away from the heart
Image: Video of venous valve in action

Veins are blood vessels that carry blood toward the heart. Most veins carry deoxygenated blood from the tissues back to the heart; exceptions are the pulmonary and umbilical veins, both of which carry oxygenated blood to the heart. Veins differ from arteries in structure and function; for example, arteries are more muscular than veins, veins are often closer to the skin and contain valves to help keep blood flowing toward the heart, while arteries carry blood away from the heart

Image: Video of venous valve in action

Apr 10

deep venous thrombosis (DVT) is the formation of a blood clot (thrombus) in a deep vein, predominantly in the legs. Non-specific signs may include pain, swelling, redness, warmness, and engorged superficial veins.
Images: Venograms of DVT

deep venous thrombosis (DVT) is the formation of a blood clot (thrombus) in a deep vein, predominantly in the legs. Non-specific signs may include pain, swelling, redness, warmness, and engorged superficial veins.

Images: Venograms of DVT

(Source: Wikipedia)

Apr 07

Measles At A Rock Concert Goes Viral
If you went to see the Kings of Leon concert on March 28 in Seattle, let’s hope you came home with nothing but great memories.
A young woman at that concert in Seattle has come down with measles, which can be spread for days by a person who’s infected but not yet sick. That’s bad news for the thousands of people who shared the concert hall with her, or were at the many other places she went that week.
And that’s why the Washington State Department of Health has published the unidentified woman’s schedule online.
"The reason we’re doing this is that it’s so highly contagious," says Dr. Jeffrey Duchin, who is chief of communicable disease control for Seattle and King County Public Health, which investigated the measles case. “It can stay in the air for hours after the contagious person has left. If we don’t treat these people, the chain of transmission can continue.”
The young woman became contagious on March 26, after visiting a family with measles cases that were linked to an outbreak in British Columbia. Unaware she was infected, she went to work at a bakery, filled her car up at a gas station, went to the concert, went to Pike Place Market and went out for sushi. All the while she was spreading viruses in the air.
So if you were at the Starbucks at 102 Pike Street between 11:15 a.m. and 2 p.m. on March 29 and you’re not sure if you’re immune to measles, the Washington State Department of Health wants you to see a health care professional immediately. You may be in the market for a quick shot of vaccine or immune globulin.
Continue reading.
Photo: This one’s virus-free: Matthew Followill, Nathan Followill and Caleb Followill of Kings of Leon performed in Los Angeles in December. (Kevin Winter/Getty Images for Radio.com)

Measles At A Rock Concert Goes Viral

If you went to see the Kings of Leon concert on March 28 in Seattle, let’s hope you came home with nothing but great memories.

A young woman at that concert in Seattle has come down with measles, which can be spread for days by a person who’s infected but not yet sick. That’s bad news for the thousands of people who shared the concert hall with her, or were at the many other places she went that week.

And that’s why the Washington State Department of Health has published the unidentified woman’s schedule online.

"The reason we’re doing this is that it’s so highly contagious," says Dr. Jeffrey Duchin, who is chief of communicable disease control for Seattle and King County Public Health, which investigated the measles case. “It can stay in the air for hours after the contagious person has left. If we don’t treat these people, the chain of transmission can continue.”

The young woman became contagious on March 26, after visiting a family with measles cases that were linked to an outbreak in British Columbia. Unaware she was infected, she went to work at a bakery, filled her car up at a gas station, went to the concert, went to Pike Place Market and went out for sushi. All the while she was spreading viruses in the air.

So if you were at the Starbucks at 102 Pike Street between 11:15 a.m. and 2 p.m. on March 29 and you’re not sure if you’re immune to measles, the Washington State Department of Health wants you to see a health care professional immediately. You may be in the market for a quick shot of vaccine or immune globulin.

Continue reading.

Photo: This one’s virus-free: Matthew Followill, Nathan Followill and Caleb Followill of Kings of Leon performed in Los Angeles in December. (Kevin Winter/Getty Images for Radio.com)

(via nprglobalhealth)

In the fetus, the ductus venosus shunts most of the left umbilical vein blood flow directly to the inferior vena cava. Thus, it allows oxygenated blood from the placenta to bypass the liver. In conjunction with the other fetal shunts, the foramen ovale and ductus arteriosus, it plays a critical role in preferentially shunting oxygenated blood to the fetal brain. It is a part of fetal circulation.
The ductus venosus is open at the time of the birth and is the reason why umbilical vein catheterization works. Ductus venosus naturally closes during the first week of life in most full-term neonates; however, it may take much longer to close in pre-term neonates. Functional closure occurs within minutes of birth. Structural closure in term babies occurs within 3 to 7 days. After it closes, the remnant is known as ligamentum venosum.

In the fetus, the ductus venosus shunts most of the left umbilical vein blood flow directly to the inferior vena cava. Thus, it allows oxygenated blood from the placenta to bypass the liver. In conjunction with the other fetal shunts, the foramen ovale and ductus arteriosus, it plays a critical role in preferentially shunting oxygenated blood to the fetal brain. It is a part of fetal circulation.

The ductus venosus is open at the time of the birth and is the reason why umbilical vein catheterization works. Ductus venosus naturally closes during the first week of life in most full-term neonates; however, it may take much longer to close in pre-term neonates. Functional closure occurs within minutes of birth. Structural closure in term babies occurs within 3 to 7 days. After it closes, the remnant is known as ligamentum venosum.

(Source: Wikipedia)

Mar 31

The Venae Cavae (blue) adjacent to the Aorta (red)

The Venae Cavae (blue) adjacent to the Aorta (red)

(Source: Wikipedia)

Mar 29

Brain metastasis in the right cerebral hemisphere from lung cancer shown on T1-weighted magnetic resonance imaging with intravenous contrast.

Brain metastasis in the right cerebral hemisphere from lung cancer shown on T1-weighted magnetic resonance imaging with intravenous contrast.

(Source: Wikipedia)

Mar 27

The last day to sign up for Obamacare without facing a financial penalty is March 31!

The last day to sign up for Obamacare without facing a financial penalty is March 31!

(via ilovecharts)

Mar 18

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Feb 28

“The practice of medicine is an art, not a trade; a calling, not a business; a calling in which your heart will be exercised equally with your head.” — William Osler

Feb 27

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Feb 26

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Feb 23

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Feb 15

A intussuception as seen on CT
An intussusception is a medical condition in which a part of the intestine has invaginated into another section of intestine, similar to the way in which the parts of a collapsible telescope slide into one another.This can often result in an obstruction. The part that prolapses into the other is called the intussusceptum, and the part that receives it is called the intussuscipiens.Early symptoms can include nausea, vomiting (sometimes bile stained [green color]), pulling legs to the chest area, and intermittent moderate to severe cramping abdominal pain. Pain is intermittent not because the intussusception temporarily resolves, but because the intussuscepted bowel segment transiently stops contracting. Later signs include rectal bleeding, often with “red currant jelly” stool (stool mixed with blood and mucus), and lethargy. Physical examination may reveal a “sausage-shaped” mass felt upon palpation of the abdomen.

A intussuception as seen on CT

An intussusception is a medical condition in which a part of the intestine has invaginated into another section of intestine, similar to the way in which the parts of a collapsible telescope slide into one another.This can often result in an obstruction. The part that prolapses into the other is called the intussusceptum, and the part that receives it is called the intussuscipiens.Early symptoms can include nausea, vomiting (sometimes bile stained [green color]), pulling legs to the chest area, and intermittent moderate to severe cramping abdominal pain. Pain is intermittent not because the intussusception temporarily resolves, but because the intussuscepted bowel segment transiently stops contracting. Later signs include rectal bleeding, often with “red currant jelly” stool (stool mixed with blood and mucus), and lethargy. Physical examination may reveal a “sausage-shaped” mass felt upon palpation of the abdomen.

(Source: Wikipedia)