Top videos

Cholecystectomy with Hysterectomy
Cholecystectomy with Hysterectomy Mohamed 14,990 Views • 2 years ago

A good case comprising of laparoscopic cholecystectomy with lap. assisted vaginal hysterectomy done simultaneously

Carpal Tunnel Release surgery
Carpal Tunnel Release surgery DrHouse 22,462 Views • 2 years ago

This is a video of a carpal tunnel release surgery

Flexor Synovectomy
Flexor Synovectomy DrHouse 10,360 Views • 2 years ago

Flexor compartment synovectomy in a patient with rheumatoid arthritis presenting with loss of finger movement and local pain due to synovitis. Performed at the Queen Victoria Hospital, East Grinstead.

From axons to tracts
From axons to tracts Mohamed 21,054 Views • 2 years ago

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.

Ford Interlocking Suture
Ford Interlocking Suture M_Nabil 12,760 Views • 2 years ago

Ford Interlocking Suture

Subcutaneous Pattern Suture
Subcutaneous Pattern Suture M_Nabil 13,805 Views • 2 years ago

Subcutaneous Pattern Suture

Deep Tie
Deep Tie M_Nabil 14,273 Views • 2 years ago

Deep Tie

Instrumental Tie
Instrumental Tie M_Nabil 9,495 Views • 2 years ago

Instrumental Tie

Use of Skin Stapler Remover
Use of Skin Stapler Remover M_Nabil 15,881 Views • 2 years ago

Use of Skin Stapler Remover

Lateral internal sphincterotomy
Lateral internal sphincterotomy Mohamed 42,387 Views • 2 years ago

Lateral internal sphincterotomy

Interscalene Block
Interscalene Block M_Nabil 9,824 Views • 2 years ago

Interscalene Block

Off-Pump CABG in Dextrocardia
Off-Pump CABG in Dextrocardia DrHouse 10,579 Views • 2 years ago

Off-Pump CABG in Dextrocardia; A New Challenge for a New Era

Laparoscopic Sleeve Gastrectomy Operation
Laparoscopic Sleeve Gastrectomy Operation Mohamed 10,259 Views • 2 years ago

Laparoscopic Sleeve Gastrectomy Operation

Cholecystectomy & Retroperitoneal Tumor Removal
Cholecystectomy & Retroperitoneal Tumor Removal Mohamed 17,700 Views • 2 years ago

Cholecystectomy & Retroperitoneal Tumor Removal

Hand Assisted Nephrectomy
Hand Assisted Nephrectomy M_Nabil 14,572 Views • 2 years ago

Hand Assisted Nephrectomy

Brain tumor resection with open approach
Brain tumor resection with open approach Scott 17,453 Views • 2 years ago

Resection of a glioblastoma multiforme, a very malignant, aggressive brain tumor.

Direct Puncture Capsulorhexis
Direct Puncture Capsulorhexis DrHouse 11,303 Views • 2 years ago

Direct puncture capsulorhexis with a slightly barbed 30g needle on a TB syringe with BSS permits excellent control even with very high vitreous pressure without use of viscoelastic. Ideal for biaxial (microincision) cataract surgery.

Repair of Pectus Excavatum
Repair of Pectus Excavatum DrPhil 15,401 Views • 2 years ago

Repair techniques for various types of asymmetric pectus excavatum are illustrated. Morphology-tailored bar shaping and selecting the hinge points are key elements of the technique. Repair of two cases on an eccentric type and unbalanced type according to "Park Classification" was demonstrated.

Thyroidectomy Modern Technique
Thyroidectomy Modern Technique Doctor 41,320 Views • 2 years ago

Modern technique of thyroidectomy for tumors

Abdominoplasty
Abdominoplasty Doctor 11,437 Views • 2 years ago

This shows a full Abdominoplasty surgery performed by Dr. Art Foley in Olympia Washington. Abdominoplasty is also commonly referred to as a "Tummy Tuck." Tummy tuck is a surgical procedure also known as abdominoplasty to remove excess skin and fat from the middle and lower abdomen and to tighten the muscles of the abdominal wall. The procedure can dramatically reduce the appearance of a protruding abdomen. But bear in mind, it does produce a permanent scar.

Showing 249 out of 378