Johns Hopkins Gazette: December 9, 1996 Form

On Technology:
MAD Scientists
Invade Small
World

Mike Field
Staff Writer
In Richard Fleisher's Academy Award winning film Fantastic Voyage, an important scientist is rescued from behind the Iron Curtain only to be severely injured by enemy agents. So dangerous are his wounds that traditional surgery is impossible, yet, we are led to believe, the future of the free world may well depend upon his recovery.

The only answer is minimally invasive surgery, but unfortunately, as it is the year 1966, the term and the concept have not quite been invented yet.

None of this, however, is enough to stop a roomful of creative Hollywood writers.

They devise a simple solution. With the use of a top-secret government ray gun, a team of scientists (including Raquel Welch) are shrunk down roughly to the size of a poppy seed and then-- whoosh!--injected into the scientist's body through the tip of a hypodermic needle. Off they go in search of wounds to cauterize and inter-synaptic globulites with which to do battle.

Fast forward 30 years to a subterranean laboratory in the Wilmer Eye Institute building, where Hopkins researchers work daily with the kinds of tools surgeons need to make their own fantastic voyages. Forceps the size of an ant's jaw. Microknives fashioned as if from a razor's edge. Light sources no bigger than a pin's head and motorized scissors scaled down to cut single cells. All small enough to fit inside a hypodermic needle, which is typically how the instruments are delivered to the operative site.

The only thing missing is an amoeba-sized Raquel Welch.

"The concept of this laboratory is that we bring together surgeons, engineers and instrument makers to take full advantage of all the new technologies currently available," said Eugene de Juan, professor of ophthalmology at Wilmer and co-director of the institute's vitreoretinal surgery program. De Juan came to Hopkins from Duke five years ago.

At Duke, a similar program that brought instrument makers into close working relationship with surgeons had caught his attention. He thought that by adding one missing ingredient-- trained engineers--the lab could not only produce new surgical tools, but help pioneer entirely new ways of performing surgery. With research grants and additional financial backing from the Storz Instrument Company, de Juan established his lab in the basement of Wilmer four years ago.

He named the new facility the Microsurgical Advanced Design Laboratory. It's the MAD lab for short, as each of the four full-time members of the team announces when answering the phone. The name may be unusual, but it fits. Engineer Scott Rader, who co-directs the laboratory with de Juan, describes the name choice as "deliberate, very deliberate."

Perhaps there is an edge of insanity working at the forefront of microsurgical technique. In a world where scissors measure half a millimeter and surgery is performed while looking through 3-D binocular microscopes, the need to get very, very small can sometimes become something of an obsession.

"Our challenge as engineers is to design entire systems that manipulate sub-millimeter instruments," Rader said. "The idea behind microsurgery is to be minimally invasive, so that the surgeon enters through the smallest incisions possible--sometimes less than a millimeter long."

The MAD lab is an inventions incubator in the grand Edisonian tradition. Rader, who holds joint appointments as assistant professor of ophthalmology and of mechanical engineering, works with a team of two other engineers and microsurgical instrument-maker Terry Shelly to design, invent and produce the kinds of tiny tools surgeons need to perform specific operations.

To date, the lab has been awarded two patents and has four more pending. De Juan estimates the 20 or so researchers who have worked at or with the lab in the past four years have come up with no fewer than 50 inventions.

The most fantastic may be their patented device for sealing off bleeding blood vessels in the eye. It performs no less than four separate functions, with a light source, an infuser, or aspirator, to draw out blood or inject liquids, a pick that can be utilized to remove scar tissue and a device to cauterize and seal open wounds. All of these fit within a .9 millimeter hypodermic needle, which is used to penetrate the patient's eye and bring the instruments to the source of trouble.

"Learning and translating to these scales is the challenge," Rader said. "The surgical instruments must start off in scale comfortable enough for the surgeon to hold in his or her hands and then, through a series of mechanical linkages, connect to the devices doing the surgery." Although much of the work done in the past four years has been directed toward surgery of the eye, the MAD lab is a resource available to any surgeon looking to find the right microsurgical tools for a specific procedure.

"Often when we have difficulty doing a particular task we think we're inadequate as a surgeon," de Juan said. "But if you can express that frustration to an engineer trained in medical techniques they get energized and start generating ideas of how to overcome the problem. That's what this lab is all about."

Although much microsurgical technique was first developed in dealing with the eye--where the surgeon has the distinct advantage of being able to directly see (with magnification) what is happening--recent advances in video-assisted laparoscopy have led to new surgical techniques in the abdominal and thoracic cavities as well.

And when new techniques are developed, de Juan said, new tools are frequently in order. "The MAD lab is involved in three major areas right now, the first of which is the development of new surgical techniques and instrumentation," he said. "We are also working closely with the development of an intraocular prosthesis, which is an electronic device designed to restore some degree of vision in patients with retinal degeneration. Finally, we are involved in designing advanced tools for new drug delivery techniques."

Devices created at the MAD lab are developed and provided to the surgeon at no cost. In return, the lab's funding arrangement with Storz Instruments gives the surgical device manufacturer first right of refusal on any new inventions. If they do choose to commercially develop the device--as they have with a number of MAD lab inventions--royalties from the sale of the manufactured instruments are returned to the lab as a source of income. De Juan notes that a second arrangement, by which a surgeon can hire the lab's expertise through contract work, is also available.

"The field of eye microsurgery really blossomed in the 1970s and have come a long way since then," Rader said of the newest frontiers of surgery. "Our goal with these devices is to minimize errors of communication in the operating room, speed up procedures, reduce recovery time and, as much as possible, give surgeons direct control over the techniques and procedures they perform."

That's a big order, but MAD lab researchers are making big advances in the field. And they're doing it by getting very very small.


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