Using ultrasound to teach living anatomy to non-medical graduate students

Abstract

Purpose

Ultrasound technology is used to supplement gross anatomy instruction in many medical sciences programs. However, this technology is not common practice for anatomy instruction in nonmedical graduate-level courses. Ultrasound sessions provide a clear view of local anatomy and could help graduate students transfer anatomical content from a didactic context onto a living, moving body. This approach to instruction complements the rapidly evolving technological advances in science education and may assist with spatial understanding, knowledge retention, and student engagement. The main objective of this article was to describe the methods used to incorporate ultrasound sessions into a graduate level gross anatomy course.

Methods

The goal of the curricula was to use ultrasound technology to create a supplemental hands-on and engaging method of learning anatomy that would appeal to graduate students and possibly reinforce content. Graduate students participated in three interactive, 2-h-long ultrasound sessions that corresponded to their gross anatomy lecture material.

Results

Questionnaire results showed that students overwhelmingly believed that the ultrasound sessions were beneficial and that ultrasound technology should be used for anatomical instruction in graduate programs. While students found the sessions to be helpful, they sought more and longer sessions with smaller group sizes.

Conclusion

Overall, this article describes the methods used to incorporate multimodal learning into a graduate level anatomy course and found that students supported the methods as a potentially effective and engaging way to supplement traditional gross anatomy lectures and practical laboratory sessions.

Appendix

Ultrasound practical session 1

MSK

Learning objectives

• 1. To illustrate the difference between various tissue types (bone, tendon, vessels, muscle, nerves) on ultrasound.

• 2. To illustrate the 3D anatomy in motion of the knee joint using ultrasound as a tool and its clinical significance.

Teaching points

Refresh from the interactive lecture session and demonstrate:

• A. Properties of the ultrasound machine:

  • a. Power

  • b. Gain

  • c. Depth

  • d. Probes/change probes

  • e. Orientation mark

  • f. How to hold the probe/tripod position

• B. Basic ultrasound of tissues

  Demonstrate the difference between the following:

  • Bone (hyperechoic with shadow)- tendon (In short axis, looks like the end of a broomstick).

  • Vessel

  • Muscle (hypoechoic, “filet mignon”)

  • Subcutaneous tissue

  • Nerve (“honeycomb cereal”)

Use the upper arm and the wrist area as example, Achilles Tendon and Gastrocnemius can also be used.

Ultrasound practical session 2

Neck/eye session

Learning objectives:

• 1. To describe the 3D anatomy of the neck using ultrasound as a tool and its clinical significance

• 2. To describe the 3D anatomy in motion of eye using ultrasound as a tool and its clinical significance

Teaching points:

Neck.

• Antero-lateral neck

  • carotid artery

  • internal jugular vein

  • esophagus, sternocleidomastoid muscle and anterior/middle scalenes.

  • brachial plexus forming a traffic light sign between the anterior/middle scalenes: site of interscalene block.

• Midline

  • Tracheal rings and associated air artifacts

  • Thyroid cartilage

  • (Optional) Vocal cords

  • Thyroid gland. Note homogenous texture and isthmus.

Face

• Ocular:

  • Note optic nerve sheath.

  • Note anterior chamber, posterior lens, posterior chamber.

Ultrasound practical session 3

Abdomen session

Learning objective:

• Describe the 3D anatomy relating to the major organs in the abdomen, including the liver, spleen, kidneys, and aorta.

Abdominal organs:

• Right upper quadrant (RUQ).

  • Positioning: with the patient supine position, locate the xyphoid process; draw a horizontal line down to the mid-axillary line; position your probe at this point with the probe marker oriented toward the patient’s head.

  • Organs to note:

    Initial view should demonstrate the liver and the mirror artifact of the diaphragm.

    • Liver: demonstrated initially in this view; note its homogenous echogenic texture and three different circulations within liver; differentiate between systemic veins and portal veins (systemic hepatic veins appear to have no wall).

    • Diaphragm: should appear as a hyperechoic line surrounding the superior border of the liver; superior to the diaphragm is lung; however in the non-pathological condition, the lung is not visible, and what you actually see is a mirror image of the liver.

    • Kidney: demonstrated by moving the probe inferior (caudally) and fanning it posteriorly; note its echogenic texture and central vasculature; note hyperechoic renal capsule, and the hyperechoic renal cortex relative to the hypoechoic renal medulla.

    • Morrison’s pouch: demonstrated as the boundary between liver and the kidney; represents a potential space for fluid to collect; Under non-pathological conditions, you should not see a clear separation between the walls of the kidney and liver here.

    • Gallbladder (fundus/body/neck): The neck points toward the portal triad (portal vein, common bile duct, and hepatic artery); because it appears as an anechoic structure within the liver, it may be confused for the hepatic or portal veins. Use color to confirm.

• Left upper quadrant (LUQ)

  • Positioning: with patient supine, locate the xyphoid process and draw a horizontal line to the left to the posterior-axillary line. This is the initial position of the probe, with probe marker oriented toward the patient’s head.

  • Organs to note:

    • Spleen: Note homogenous echo texture; by fanning anteriorly, you may be able to see stomach bubble.

    • Diaphragm: visible as a hyperechoic line on the superior edge of the spleen; note mirror artifact

    • Kidney: demonstrated by moving probe inferiorly; note hyperechoic renal capsule, and the hyperechoic renal cortex relative to the hypoechoic renal medulla

    • Spleno-renal recess: the potential space between the spleen and kidney; under non-pathological conditions, there is very little separation between the two organs, resulting in a close approximation at the interface of the organs

Aorta–Positioning—orient the probe similarly as the subxiphoid heart view; scan inferiorly down the abdomen looking for major branches; rotate the probe 90° to visualize structures in longitudinal view.

• Structures to note:

  • Spine: the most posterior structure in the midline; may see spinal canal.

  • Inferior vena cava is to the patient’s right and abdominal aorta (AA) is to patient’s left.

  • Celiac trunk: First branch to come off AA; bifurcation into splenic and common hepatic arteries may create a “seagull sign”.

  • Superior mesenteric artery (SMA): second branch to come off of AA, around 0.5–2.0 cm distal to celiac trunk.

  • By scanning further inferiorly, you will see the splenic vein arching over SMA.

  • Renal arteries and veins: arise 1.0–1.5 cm inferior to the SMA; the right renal artery travels posterior to the IVC and the left renal vein crosses between SMA and aorta.

  • Bifurcation into common iliac arteries occurs at about the level of the umbilicus (LV4).

  • Once you have identified celiac trunk and SMA in transverse view, rotate the probe to demonstrate them in the longitudinal view as well: Celiac trunk comes of aorta and travels superiorly, while SMA will come off aorta just distal and travel inferiorly.