The mystery of a manikin collection

In the Josiah Charles Trent History of Medicine Room at the Rubenstein Library, Duke radiology research fellow Fides Schwartz unrolls a little hand-sized puff of bubble wrap and lays out on the table all the pieces of a neat, slightly translucent white medical manikin, about six inches tall. The body of a woman: She’s pregnant, and her midsection lifts off, revealing removable heart, lungs, baby. “You see?” Schwartz asks. “Actually it does all fit together.”

She points out the details: “The little baby holding its hands up to its face,” she notes in delight, and to be sure, the baby, about the size of the nail on your pinkie, is curled up, its little hands in fists on either side of its head.

The manikins aren’t new—they’re old and rather mysterious, part of the collection of medical materials (equipment, manuscripts, and an unforgettable tray of glass eyes) donated by Trent and his widow, Mary Duke Biddle Trent Semans ’39. The twenty-two manikins are tiny, intricately carved anatomical dolls probably made in the late seventeenth century in Germany. They were long thought to be tools for medical teaching, but that now seems unlikely, Schwartz notes, since it turns out they were made of ivory, which is pretty expensive material for something students were going to handle a lot. They’re now suspected to be collectibles or perhaps even toys.

That they’re definitely made of ivory is something Schwartz has helped figure out. There are fewer than 200 of these figurines worldwide, so as an effort toward protection and understanding, the library began having the manikins scanned in 2018. The one Schwartz carried around was, in fact, a 3D print made as a result of those scans. “The goal is to share them [through both image and 3D print] to a wider audience that ranges from medical professors, to students, to art historians,” says librarian Rachel Ingold. And, not incidentally, radiology research fellows.

Schwartz read about the scans and reached out to Ingold. “Librarians love helping people,” Ingold says. Says Schwartz, “So I was allowed to look at all the scans and to attend a scan, too.” As a radiologist, she says she thought, “If we have a CT scan of it, we can do more with it than just look at the surface.”

In fact, those are micro-CT scans, which enable viewers to look down to the cellular level, enabling Schwartz to make her diagnosis of the manikins’ makeup. Micro-CT scans have a resolution from forty to 100 micrometers. A human hair is about 100 micrometers wide, and a cell is about fifty micrometers, so the scans enabled Schwartz to recognize the cellular structure of the manikins’ material. “Almost all of them are wholly made of ivory,” she says. “One seems to be made of deer antler, and one, most is ivory and one piece is whalebone.”

Elephant or mammal ivory is easy to recognize: “because it’s a tooth,” she says. “Layers of dentin, very densely packed, it looks a little like tree rings. As soon as you see one slice you know.” Bone, on the other hand, has a different structure, including Haversian canals—tubes for blood vessels and nerves. Whales live underwater, and their bones are buoyed by the sea, so whalebone canals are more rounded than the ones in deer antlers. And by the way, yes, antlers are bone, unlike, say, rhinoceros horns, which are more like claws or hair. “I learned this through this project,” Schwartz makes clear, laughing; she didn’t come to Duke an expert in ivory, antler, and whalebone.

Encouraged by her fellowship mentors and supported by a panoply of Duke technicians, scholars, and doctors (the research has seven coauthors), Schwartz submitted her findings to the Radiological Society of North America for its annual meeting. About 13,500 abstracts are submitted for presentation, of which the society accepts about a tenth. The results presented by Schwartz were not only accepted but chosen as one of the dozen or so highlighted in the conference news release. This led to press briefings and stories all over the world. “I was not expecting anything like that,” Schwartz says.

It’s an unexpected world. Not long after the manikins results, Schwartz was watching scans of objects for Duke’s Nasher Museum.