AnatomyBox

Discovery of a new part of the anatomy…(but it is only 15 microns thick!)

Dr. Harminder Dua, a professor at the University of Nottingham, has discovered a new layer in the human cornea. In true anatomist fashion he is calling it…that’s right…Dua’s layer.

Dua had previously postulated the existence of an additional layer to the cornea as a result of his experience in performing many Deep Anterior Lamellar Keratoplasties (DALKs).

Traditional corneal grafting surgery usually involves removal of the entire cornea. Which sacrifices the outer aspect, stroma and inner aspect of the cornea. Of these numerous layers, the endothelium is the functional layer of the cornea. It serves to pump fluid from the cornea and therefore maintains its clarity.  Using this traditional approach removes the functional endothelium along with the cornea and replaces everything with donor tissue.

DALK is another method of removing the cornea during transplant surgery. The entire outer aspect of the cornea is removed along with the underlying stroma all the way down to Descemet’s membrane (see the histological figure I have provided for orientation) using the Big Bubble (BB) technique. A method which uses air to get between Descement’s membrane and the overlying stroma allowing them to be separated during surgery.

It was during these procedures that Dr. Dua noted the presence of a new layer. This was then verified using light, transmission and scanning electron microscopy. The illustration I have provided approximates the location of the thin Dua’s layer.

Researchers believe that a tear in Dua’s layer is the cause of corneal hydrops, a disorder that leads to fluid buildup in the cornea. According to Dua, knowledge of the new layer could dramatically improve outcomes for patients undergoing corneal grafts and transplants.

“This is a major discovery that will mean that ophthalmology textbooks will literally need to be re-written,“ Dua says. “From a clinical perspective, there are many diseases that affect the back of the cornea which clinicians across the world are already beginning to relate to the presence, absence or tear in this layer.”

Let me be one of the first to welcome Dua’s layer into anatomical existence.

i-heart-histo

Reference: Dua, H.S., Faraj, L.A., Said, D.G., Gray, T., Lowe, J., 2013, Human Corneal Anatomy Redefined (A Novel Pre-Descemet’s Layer - Dua’s Layer), Ophthalmology (in press)

The Boy Who Grew a Brain

Noah Wall was born with only 2% of a brain (left), spina bifida and severe hydrocephalus. Doctors predicted that even if he survived, he would suffer severe mental disability and have limited mobility for the rest of his life. 

After surviving his birth, Noah only improved with time. His parents worked with him to learn and grow to live as normal a life as possible, and doctors were stunned with the progress he was making. After 3 years, Noah was scanned again and the results showed his brain had grown to over 80% the size of a normal, healthy brain (right). Noah continues to live a happy life and progress even more, and his unusual case sheds light on the incredible capabilities of the human body and brain.

pinball machine 

The artist — recent winner of the $5,000 emerging artist award from the Council of the Arts in Ottawa — was asked by a gallery to create works for an exhibition on the bicentennial of War of 1812, with a theme on the health-care side of battle. Tsui was skeptical, but research taught him that battlefield surgery “was a really messy procedure,” he tells me during an interview in his Centretown home. “Since a musket (ball) isn’t aerodynamic, when it enters your body it doesn’t come clean out, like a modern bullet, it just kind of rattles around in your torso.”

Others might imagine that ball rattling around their innards and think “ouch.” What Tsui thought was, “it’s kind of like a pinball machine.” His art project on historic military health-care was born.

“Santiago Ramón y Cajal was a Spanish pathologist, histologist,neuroscientist, and Nobel laureate. His pioneering investigations of the microscopic structure of the brain were original: he is considered by many to be the father of modern neuroscience. He was skilled at drawing, and hundreds of his illustrations of brain cells are still used for educational purposes today.

chocolate heart

Acute Osteomyelitis - Historically known as “Bone Fever” Osteo-: Bone -myelo-: Marrow -itis: Fever

Top: Acute supperative osteomyelitis in femur - note the purulent cavities and pus-filled medullary canal at A, B, and C. In this case, the epiphysis (E) and conjunctive cartilage (D) are uninfected. Center Left: Acute osteomyelitis of tibia, cicatrices showing common position of sinuses in bone. Center Right: Acute epiphysial separation due to osteomyelitis following typhoid fever. Bottom: Early stage of acute osteomyelitis in tibia. Note site “A” - where the infection passed from the periosteum to the interior of the bone. The articular cartilages © are sodden with pus from the infected joint.

Acute osteomyelitis is most commonly seen in children and those with diabetes. It is rarely “spontaneous” - the bacteria that infect the subperosteum and marrow have to be introduced into the bloodstream somehow, and there is usually a known source. Systemic infection or traumatic injury are the most common ways that bacteria (today, most commonly Staphylococcus aureus) can get to the bones. Historically, scarlet fever (caused by group A Streptococcus pyogenes) and typhoid fever (Salmonella typhi) were known to cause a large number of osteomyelitis cases in their wake.

When children develop osteomyelitis, the long bones of the body (the femur, humerus, etc.) are most often affected, whereas the spine and pelvis are most commonly affected in adults. This is because there is much greater bloodflow to the growing long bones in kids, and as such there’s much more opportunity for bacteria in the blood to infect the site.

Early symptoms of what used to be called “bone fever” are fever and bone pain (as one might assume), as well as local warmth and swelling, and an overall malaise. The bone infection usually presents after a patient appears to have recovered from a disease or wound, as it takes several days to become established enough to cause symptoms. Later on, if left untreated, extreme pain and open, often purulent, wounds above the infection may occur, as the bacteria bore canals through the affected bones.

Without treatment, osteomyelitis can lead to sepsis, complete breakdown of affected bones, or gangrene. When the epiphysis is affected by the infection, growth of that bone can be significantly stunted.

Today, the condition is usually treated with long-term, high-dosage, IV antibiotic therapy. If it’s not caught at the start of the infection, debridement of the bone (removing the infected tissue) may be required, and in extreme cases, bone resection (cutting out an entire chunk of infected bone) or amputation may be required. Prior to antibiotics, resection was the most common cure.

Human Parotid | Sarah Knox

You Think Beauty Is Skin Deep? You’re Not A Chiropractor

When the nation’s chiropractors descended on Chicago for a weeklong convention in May 1956, they threw a beauty contest.

Silver skull vinaigrette, Europe, 1701-1900