Sketches/Study Guides

For gross anatomy I’ve been sketching from both my books and the cadaver as study guides. We’re currently studying the head and neck so I traced the blood flow through the internal and external carotids and the venous drainage into the jugular veins. The blood flow to the face is extensive with several areas of anastamoses, hence the heavy bleeding resulting from any injury to the face or scalp. I marked clinically important areas of communication that I should be aware of. Primary areas of concern are the ophthalmic artery’s role in connecting the internal and external carotids and the danger area where infection can spread into the cavernous sinus through the ophthalmic veins.

Internal and External Carotids

Jugular Veins

I also illustrated the branching of the facial nerve to understand where it went, what it innervated, and what fibers it carried. It’s important to note that you shouldn’t believe everything you read in the text because they make mistakes all the time. In this instance the book read that the fibers of the branches to the muscles of facial expression, stapedius, posterior digastric, and stylohyoid were special visceral afferents. I thought I’d gone completely insane because I was sure muscle innervation was through efferent fibers. I checked another book which confirmed my suspicions: SVE fibers go to facial muscles, SVA fibers are on the facial nerve but they deal with the special sense of taste on the anterior 2/3 of the tongue and soft palate.

The Facial Nerve

Surface anatomy and internal structures

I’m nearing the end of my first semester of grad school. It’s bizarre to think that this is the 2nd to last project in my anatomical visualization course. We illustrated the figure in anatomical position and superimposed the underlying skeleton and organs of our choice. This one required the illustrations to be done using line work to practice with a more technical style of drawing. Artistically, it was important to show variety in line weight and convey the sense of the form without the use of tone. Anatomically, it was important to line the surface anatomy up with the underlying structures. For example, the suprasternal notch lies at the junction between the sternum and the clavicles, the umbilicus sits at about the level of L4, the nipples on males sit at the level of the 5th rib, and the anterior superior iliac spines, costal margins, and iliac crests all serve as visible landmarks for placing the deep anatomy. All this is useful for drafting a proper, “normal,” skeleton.

The final skeleton

From there the skeleton could be used to place whichever organs we chose. I illustrated the kidneys and spleen, because I think they’re cool. Don’t know why, maybe it’s the shape or something, but I really like them a lot. In order to place them I found the location of my transpyloric plane, which sits about the level of L1 half-way between the suprasternal notch and pubic symphysis and aids in the placement of many organs. The hilum of the right kidney should sit slightly above the plane while the left is slightly below. The hilum of each sits about 2″ from the midline. The left kidney sits between the levels of T12 and L3 while the right sits slightly lower. The spleen was a bit difficult to place but it lies mainly alone the left 9th, 10th, and 11th ribs pushed right up against them anterior to the kidneys. As it looked like the spleen was one giant tumor coming off the left kidney without any grounding between them I also added the abdominal aorta with the renal and splenic arteries to give them some relationship.

Kidneys, ureters, bladder, spleen

From there it was a matter of bringing it all into photoshop and overlaying all the layers into a composite image, then dropping in the labels for all the important structures. Overall I’m actually really pleased with the way this one turned out. It took a bit of time, some research, reworking, and the painful realization that I picked a career that would require my to draw an anatomically correct rib cage for the rest of my life, but I think I really got the placement of everything just right.

The final product

Long overdue figure drawings

So I planned on posting these a while ago (i.e. back when I first did them a couple weeks ago) but then anatomy exam number two started to creep up on me and I stopped being a function human being. Huge exams on the entire thoracic, abdominal, and pelvic/perineal regions will do that to you. Anyway, here’s some quick gesture drawings I did to get back into the swing of things. I’d forgotten how much I enjoy figure drawing. The long pose was used as preparation for our fourth project in anatomical visualization and will be up within a few days.

Quick gestures

Slightly longer poses

Anomalous Left Hepatic Vein

So I finished my drawing of the heart. This specimen displayed several anomalies, including a persistent left hepatic portal vein, posterior interventricular cardiac vein, and middle cardiac vein which all drained directly into the right atrium along with the SVC, IVC, and diminished coronary sinus. The tricky part of this assignment was finding reference for an inferior-posterior view of the liver and the way in which it articulated with the heart. I found that the view point I had would have resulted in the liver obstructing most of the heart so I chose to ghost the liver in rather than rendering it in its entirety. This was pretty helpful to as there was nothing competing for attention with the rendering of the heart, so focus could be directed towards the anomalous vessels.