Medical Exhibits - Demonstrative Evidence Expert Blog - MediVisuals

Medical Legal Illustration and Animation - Cross Sections

Posted by Tara Rose on Mon, Jun 18, 2012

By: Robert Shepherd MS, Certified Medical Illustrator, Vice President and Director of Eastern Region Operations,MediVisuals Incorporated

Long before science had advanced to allow imaging of the body in sectional views by computed tomography (CT) and magnetic resonance imaging (MRI), medical illustrators were illustrating the body in sectional views because these views are the best way to appreciate some anatomical relationships. 

Medical illustrators, physicians, and others who have studied anatomy are familiar with sectional views of the body and appreciate the value of these views in explaining the relationship of anatomical structures. However, accomplished and well respected jury consultants and non-medical illustrator legal graphics experts have expressed concerns that sectional views may be difficult for some jury members to understand. These individuals' opinions are valuable to those of us in the legal graphics business, and I agree with their opinions that, when other views can communicate a particular relationship message equally as well or better, sectional views should be avoided. I also believe most of these experts will agree that there are times and places in which sectional views of anatomy are the best way to appreciate some anatomical relationships. Granted, there have been times when we have been working on specific cases and experts have insisted that sectional views be absolutely and unconditionally avoided. Unfortunately, in these situations the experts were unable to suggest a more effective view to communicate the relevant anatomical relationships (at least in a way that was practical in terms of time and expense). That being the case, sometimes the sectional views were used despite the input of the experts, and at other times, the relationships of the structures had to be explained without the benefits of graphics.

A way to perhaps explain how sectional views help decision makers appreciate relevant anatomical and pathological relationships is to compare them to aerial views or photographs of the scene of a collision.  Space is defined in three planes. Only two of these planes can effectively be demonstrated in a two-dimensional rendering. For example, aerial views have long been used to help explain the positions of vehicles and structures that simply can't be appreciate from "street views". When viewing the scene of a collision from a "street view", one can appreciate vertical and horizontal distances, but not depth; distances close to and far from the viewer's perspective are very difficult to appreciate (see the below figures). By comparison, when viewing an operative site through a "surgeon's view", vertical and horizontal distances can be appreciated, but the depth of the incision and the relationships of the various structures within and around the incision are very difficult or impossible to appreciate.

 

Cross Section Blog image1 REVISED

 

The "aerial view" of the collision scene allows the viewer to appreciate distances in two geographical planes as well (distances right and left, and toward and away from the "street view," but the ability to appreciate up and down is lost). Also, the locations of relevant structures or vehicles that may have been obstructed by nearby structures (such as buildings trees, signs, or other vehicles) can now be appreciated. Similarly, a sectional view of anatomy can help decision makers appreciate depth relationships of structures. Or, a sectional view of a step in a surgical illustration can allow the viewer to appreciate the depth of the surgery as well as the additional structures that may have been injured (or at risk of injury) during the invasive procedure.  These specific depth  relationships could not be appreciated from the "surgeon's view" of the same surgery shown in the above illustration.

 

Cross Section Blog image2 REVISED

 

Exhibits developed to help explain the invasive nature of a surgery and the disruption of the soft tissues during operative procedures are critical. For that reason, sectional views are critical in aiding a testifying physician to explain these issues. For example, the exhibit panel that demonstrates an anterior cervical discectomy and fusion (ACDF) that does not include a cross-section through the neck fails to emphasize the depth of the incision and disruption of tissues (essentially all the way to the center of the neck). This depth simply cannot be appreciated in a "surgeon's view".

In order to appreciate cross-sections, orientation views that show the level and direction of the section are helpful (see below), or when time, budget, and presentation format (digital as opposed to a physical panel) allow, a short animation showing the sectional view actually coming out of the orientation view such as MediVisuals' "Scan SelectorTM" can be used.

 

cross-section plane of brain hematoma

Topics: intervertebral disc, coup-contracoup, medical-illustrator, trial exhibit, disc herniation, degenerated disc, disc bulge, trauma, hematoma, traumatic-brain-injury, medical exhibits, medical-legal-illustration, disc injury, brain, TBI, medical expert, intracranial, surgery, MediVisuals, medical exhibit, personal injury, spinal injury

Attorneys: Reduce Travel Time and Expenses when Meeting with Medical Experts

Posted by Trisha Haszel Kreibich on Wed, Jan 12, 2011

By: Robert Shepherd MS, Certified Medical Illustrator, Vice President and Director of Eastern Region Operations, MediVisuals Incorporated

It is now possible for two or more people to simultaneously "share" computers from anywhere in the world through web conferencing. One of the best applications we at MediVisuals have found for this software is to enable the attorney, medical expert and medical illustrator to review and discuss imaging studies simultaneously from their respective offices.

Web conferencing significantly reduces travel time and expense. For example, a recent case required us to team up with a testifying expert located in the Midwest and an attorney in another region. Instead of meeting face-to-face, we tried screen-to-screen contact and found it worked remarkably well. Web conferencing enabled all three of us to maneuver through the imaging studies and move the cursor to specific areas of the films that were being discussed. This, along with simple telephone conferencing, allowed us all to speak with each other as we viewed the same images on our respective computer screens.

Web conferencing makes it easier than ever for us to work with attorneys and medical experts anywhere in the world. The required software programs are simple to use and affordable. The main hurdle involves ensuring the other participants' computers have fast and reliable Internet connections (i.e. DSL or Broadband) and that their web browsers are up-to-date to support the software. Confirming the second/third party Internet and computer capabilities takes no more than a phone call.

Most web conferencing software providers offer a free trial and quick web tutorial, which decreases the learning curve associated with understanding a new program. For the real tech-savvy, some developers even offer applications adaptable to 3G and 4G Smartphones and devices such as the iPad.

If you are interested in introducing web conferencing to your firm, the following is a list of links to recommended software providers’ websites:

Log Me In
http://www.logmein.com

Go To Meeting
http://www.gotomeeting.com

Cisco WebEx
http://www.webex.com/

Yugma
https://www.yugma.com/

MegaMeeting.com
http://www.megameeting.com/

Topics: medical-illustrator, trial exhibit, medical expert, medical exhibit, web conference

Soft Tissue Injury - Cervical and Lumbar Strain

Posted by Delia Dykes on Fri, Mar 12, 2010

By: Robert Shepherd MS, Certified Medical Illustrator, Vice President and Director of Eastern Region Operations, MediVisuals Incorporated 

Injuries to the spinal and paraspinal ligaments and muscles can result from violent side-to-side motions or by violent excessive flexion and extension. The illustration below shows the major ligaments of the neck (anterior longitudinal and interspinal ligaments) in hyperflexion and hyperextension, which can be injured grossly or microscopically.

cervical-strain-injury

Click to enlarge

The series of three illustrations in the bottom right corner (which is shown in more detail below), show a close-up view of the spinal anatomy in 1.) the Normal condition, 2.) during Excessive Stretching and 3.) After Healing. In the Normal condition, one can appreciate the close relationship between the muscles, nerves and blood vessels. During Excessive Stretch, small tears occur, which causes bleeding in the muscle fibers. After Healing, scar tissue and inflammation entrap blood vessels and nerves resulting in a permanent state of compromised, painful movement.

muscle-stretched
 

The same is true for the lower lumbosacral spine and pelvic regions. In the illustration below, the spinal nerves and their posterior branches are seen in close approximation to the ligaments and joint capsules, which are often involved in the injury. During hyperflexion of the lumbar spine, transient bulging of the intervertebral discs can occur. 

 

lumbar-strain-injury

Click to enlarge

The series of illustrations in the lower right corner of the above image, show the normal lumbosacral and pelvic muscles and tendon fibers, which insert on the bones near the associated posterior spinal nerve branches. During Excessive Stretch, a segmental artery and its branches may be involved in hemorrhaging, scarring and occlusion. After Healing, scar tissue and adhesions form, entrapping nerves and blood vessels, causing chronic pain.

In these next illustrations, muscle is shown in sequentially higher magnifications, which can be used to explain excessive stretch injuries in any area of the body.  In the Normal series, the bottom illustration depicts nerves and small body vessels intertwined in muscle with its tendinous attachment to the bone.  The middle illustration shows a magnified view of an individual muscle fiber and the top illustration depicts the relationship of the microscopic myofilaments (actin and myosin) in their normal relaxed position.

 muscle-normal

 

In the Excessive Stretch series, the bottom illustration shows the muscle, tendon, blood vessels and nerves as they are excessively stretched. Small hemorrhages are seen escaping from the stretched and torn blood vessels. In the middle illustration, blood is shown escaping into surrounding spaces, reducing oxygen exchange to the muscle and irritating the delicate structures of the muscle fiber. The top illustration depicts the myofilaments, showing the actin and myosin fibers torn and stretched past the point of normal interdigitation.

 muscle-excessive-stretch

 

 

 

 

In the After Healing series, the bottom illustration shows the irregular outline of the scarred and inflammed muscle fiber with small adhesions seen between the blood vessels, nerves and muscle fibers. The middle illustration shows scar tissue and inflammation occluding blood vessels and adhering the delicate structures of the muscle fibers together, limiting motion and causing chronic pain. Lastly, the top illustration depicts the damaged myofilaments. Their normally well-organized, interdigitating arrangement is left destroyed, limiting muscle movement at the most basic level.

muscle-after-healing
   

Topics: mechanism of injury, coup-contracoup, demonstrative evidence, soft tissue injury, hyperflexion, lumbar strain, hyperextension, medical-legal-illustration, medical expert, spinal injury, cervical strain, connective tissue