Gerald P. Hodge, an acknowledged master of medical illustration whose drawings helped instruct generations of aspiring physicians in the most intricate of surgical procedures, died of cancer on June 7 at his home in Ann Arbor, Mich. He was 91.

The death was confirmed by the University of Michigan, where in 1964 he was founding director of the university’s master’s degree program in medical illustration. Since retiring in 1987, he had been an emeritus professor at the university’s medical school and school of art.

The best of medical illustrations — with their blend of creative art and descriptive science — may be compared with such works as the ornithological paintings of John J. Audubon.

Schooled in art and science, “Jerry” Hodge was an heir to artists who, through the centuries, had striven to portray the human form in poses dramatic and realistic. He helped shaped the profession of medical illustration and was recognized as a leader among those who, with pen and paintbrush, depict the body as it is in life, with the dynamic interplay of nerve and muscle, tendon and bone.

“He was a consummate artist,” said Gary Lees, the chairman of Johns Hopkins University’s medical illustration department and a former student of Mr. Hodge’s. “His work was magnificent.”

According to Lees, the task of the medical illustrator is to tell the “stories” of an operation. The illustrator goes into the operating room and, while taking visual notes, listens to the surgeon describe the finer points of maneuvering through the body.

Unlike a camera, an artist like Mr. Hodge can emphasize, shadow or eliminate content as needed. The illustrator may remove from the final drawing extra sets of hands or clamps “not in the action area,” Lees said. “He may get rid of the blood, not because it’s gory, but because it’s an obstruction to a viewer.”

Combining imagination, insight and painstakingly anatomical accuracy, Mr. Hodge’s work proved valuable for training physicians and provided a guide for surgeons embarking on new procedures and operations, according to the Journal of Biocommunication. He received the Association of Medical Illustrators’s Lifetime Achievement Award in 1988.

Gerald Parker Hodge was born Dec. 3, 1920, in Denver, where his father owned a company that sold coal. After graduating from the University of Colorado in 1943 with a fine arts degree, he served in the Army during World War II and participated in the invasion of the Pacific island of Okinawa.

In 1949, he received a certificate of medical illustration from Johns Hopkins University’s medical school, where he studied under the celebrated illustrator Ranice Crosby. Mr. Hodge then worked as a medical illustrator at a cancer clinic in Missouri and as director of Louisiana State University’s medical illustration department before joining the University of Michigan faculty in 1955.

In 1949, he married Claire Ewell, whom he had met in drawing class at the University of Colorado. She died in 2007. Survivors include two children, Melinda Hodge of Lock Haven, Pa., and John Hodge of Quincy, Ill.; a brother; and two grandsons.

Mr. Hodge spent 15 years as a visiting professor at the University of Toronto and directed workshops at the Smithsonian Institution and the New York Botanical Garden. In addition to his illustrations of the human body, Mr. Hodge was known for work with archaeological, botanical and insect specimens.

He was often cited as an exemplar of the school of painting know as trompe l’oeil, a French term meaning “fool the eye.” This deception is achieved through almost photographic precision in drawing along with techniques that create the illusion of three dimensions on a two-dimensional surface.

In a brief autobiographical sketch, Mr. Hodge cited the “love of detail and working on a small scale” that led him to scientific illustration. The close observation, patience and accuracy required for such work, he said, he also applied to his trompe l’oeil paintings.