Medical Devices

Heart Valves
Enormous amounts of research, dollars, time, effort, and concern have gone into development of valves. In an effort to find the ideal replacement for heart valves, innumerable designs have been introduced, applied, and discarded. Early materials used in valve construction included stellite, knitted teflon, Silastic rubber, and polypropylene pyrolite carbon; these same materials are used in today's artificial valves.

Heart valves may be grouped into four general design types: caged ball, caged disc, tilting disc, and bioprostheses. While designs may vary, they all have a common purpose, that of replacing the diseased valve and restoring to normal flow of blood through the heart. Within the groups, the valves may have slightly different modifications.

The physical must have a means of securing the valve to the surrounding tissue; the white fabric area you see around the base of the artificial valves is the sewing ring. This area allows the surgeon to suture (sew) the valve in place.

Researches are now beginning to analyze the effectiveness of valves implanted thirty years ago. Although great progress has been made, the ideal valve is not yet available.

The Pacemaker
The heart is a pump made of special muscle, pumping blood with oxygen and nutrients to all body cells. The sinus node is the heart's natural pacemaker, and is a group of special cells in the muscle wall of the right atrium. These cells produce electrical impulses which cause the heart to beat.

From the sinus node, the impulses travel down certain paths in the muscle walls, causing the heart to contract and pump blood. As long as these electrical impulses flow down the heart walls at regular intervals, the heart pumps at a steady pace. When something happens to interfere with these impulses, such as heart attack or chronic heart disease, the sinus node may be unable to perform effectively.

If the heart pumps too quickly or too slowly, or irregularly, it cannot send as much blood to all parts of the body ands not enough oxygen and nourishment get to the cells. In this situation, the implantation of an artificial pacemaker may be the appropriate course of action.

An artificial pacemaker works in much the same way as the sinus node. It is a small electronic device that uses batteries to produce the impulses needed to make the heart pump. The impulses flow through tiny wires to the heart and are timed to flow at a certain rate just as the impulses from the recipient's natural pacemaker used to do.

Source: American Heart Association, Living with Your Pacemaker

Electro-convulsive Therapy Unit
circa 1950
Manufactured by the Bioengineering Resource Facility, UI

Electro-convulsive therapy (ECT) has been used with some success to treat psychiatric disorders since its invention in 1938. This electro-shock unit was purchased as a kit and assembled by the Bioengineering Resource Facility at the University of Iowa.

Convulsive therapy was originally explored because there was clinical evidence that epileptic seizures temporarily decreased psychotic symptoms including hallucinations, agitation and delusions. It was believed that schizophrenia and epilepsy could not occur in the same person. Thus, in an attempt to treat schizophrenia, seizures mimicking epilepsy were triggered artificially in patients suffering from psychoses. Brain seizure was induced with drugs until electric shock was found to be safer and more reliably controlled.

This electro-shock unit generates an electrical current which is administered through electrodes placed on the head. Muscle relaxants are given to patients to reduce the muscular movements which accompany brain seizure.

Electro-convulsive therapy has been used primarily in the treatment of depression and became a routine treatment in the 1950's. A patient might receive six to eight treatments over the course of a few weeks. The treatment came under public scrutiny in the 1970's, when many people argued that it was cruel and dangerous and created a range of permanent side effects. ECT became the focus of debates on the humane treatment of the mentally ill.

Effective anti-depressant drugs, developed in the 1960's, led to a reduction in the use of ECT. Today, however, with more refined technology, electro-convulsive therapy is still in use as a treatment for depression.

Gift of the Department of Psychiatry, UIHC

Pill Dispenser
circa 1930

Louis C. Arp, MD, used this "grip" or dispenser while making house calls between 1925 and 1935 in the Quad Cities area. This case holds several vials containing medicines administered for various ailments, including migraine headaches and sore throats. The labels on the vials indicate that large pharmaceutical firms such as Upjohn prepared these tablets, yet many of the formulas were derived from traditional nineteenth century pharmacopoeias.

As a general practitioner, Dr. Arp performed surgery as well. His daughter, Mary Arp Folk, who donated the pill case, explains that "after operating all morning at one of five hospitals, including Moline City, Moline Lutheran, and Davenport Mercy, my father saw patients all afternoon. Then he made home calls with his 'grip,' until dinner time. After dinner he kept evening office hours. I remember the quiet noises in the night when he left to deliver babies."

Health insurance programs were a rarity at this time. Dr. Arp held a free clinic every Thursday afternoon; patients could either pay as they went out the door, or in installments, as their circumstances permitted.

The Arps were a family of physicians; Dr. Louis C. Arp's father and brother also practiced medicine.

Gift of Mary Arp Folk, Iowa City

Transplant Organ Container
Manufactured by William D. Peterson and Associates,
Salt Lake City, Utah
circa 1969

A Boston plastic surgeon pioneered the first kidney transplant in 1952. The first transplant completed at The University of Iowa Hospitals and Clinics was performed by Richard L. Lawton, MD, in November, 1969. Although a living kidney from the patient's brother was used in the initial operation, subsequent transplants relied upon kidneys recovered from cadavers.

In 1970, Dr. Lawton established a donor system by traveling to hospitals around the state and recovering the organs himself. This organ transplant carrier was used from 1969 to 1976 to transport viable kidneys. The carrier, designed at The University of Utah, kept organs sterile and cold. An interior plastic container held up to two kidneys and was supported in a metal container. This metal container was held securely inside the closed carrier and was surrounded by ice to maintain a four degree centigrade temperature.

Upon arrival at the transplant site, donated kidneys were tested for blood and tissue compatibility and could be preserved for use in surgery by "dynamic perfusion," a process in which a solution was pumped through the kidneys to keep them vital for about a day. Today kidneys are preserved by cold storage for up to 24 hours before transplant.

Gift of Richard L. Lawton, MD, Iowa City

Fluoroscopy
The fluoroscope is a medical imaging device used for examining internal organs by means of roentgen rays. It consists of a screen covered with crystals of calcium tungstate which when stimulated by X rays will fluoresce, or emit a visible greenish light. When the area to be examined is placed between an X-ray tube and a screen, the screen will project the shadows of the X rays passing through the body. As a result, the outlines of bones and organs can be directly observed.

Hand-held Fluoroscope
circa 1910

Although Italian scientists invented the fluoroscope, Edison contributed to its development and improved its imaging capability. His fluoroscope resembled a stereoscope, allowing both eyes to focus simultaneously on the image. To improve the sensitivity of the fluorescent screen, he coated it with calcium tungstate which fluoresced more brightly than the traditional coating of barium platinocyanide.

Edison first demonstrated his fluoroscope in May 1896 at the National Electrical Exposition in New York. Many people examined their hands with the extraordinary new device. Among the men conducting the experiment was Clarence M. Dally. He had often held his hand over the X ray tube when making adjustments to the induction coil. Lengthy exposures to the dangerous rays over a period of years caused burns on the face and hands of Dally. The safety-conscious Edison immediately discounted experimenting with the harmful rays, but Clarence Dally died in 1904, one of the earliest X ray martyrs.

On loan from the UI College of Medicine

Insulated Carrier for Eyes
circa 1955

This "thermos jug" cannister was used to transport donated eye tissue, collected from around the state, to the Iowa Lions Eye Bank here at The University of Iowa Hospitals and Clinics. Established in 1955 under the direction of Alson Braley, MD, the Iowa Lions Eye Bank has made possible the transplant of over 3,400 corneas. Through a coordinated volunteer effort, delicate eye tissue is collected from deceased donors by physicians and specially trained morticians and is made available for transplant.

Eye tissue must be removed within four hours after death. The insulated eye carrier, filled with ice, protects and preserves donated eyes during transport to the Eye Bank. Delivery to the Eye Bank should be within 15 hours. The Iowa Highway Patrol transports the carrier, without charge, to Iowa City, where Eye Bank technicians screen and process the tissue. Once cornea tissue is prepared for transplant, it is usable for up to four days.

Today there are more than 30 doctors who perform cornea transplants in Iowa. Physicians who perform transplants in other Iowa communities receive the eye tissue from the Lions Eye Bank by bus. During a Greyhound strike, Tissue Procurement Coordinator Richard Feeney made deliveries to transplant physicians himself.

Time is critical in the processing of eye tissue for transplant. In the 1950's Dr. Braley, then head of the Department of Ophthalmology at The UIHC, helped extend the volunteer effort by setting up a nationwide ham radio network to coordinate cornea collection and delivery. Today a computer network links eye banks and hospitals nationwide.

The eye carrier is part of an Eye Bank kit, which has been placed in hospitals around the state. In 1964, the steel cannister was replaced by small polystyrene containers which are much less expensive, yet just as effective. The lower cost and smaller size of the new containers allow a wider distribution, and consequently a more extensive collection of eye tissue.

Gift of the Iowa Lions Eye Bank, UIHC

History of Contact Lenses
Leonardo da Vinci (1452-1519,) Rene Descartes (1596-1650) and British scientist and physician Thomas Young (1773-1829) all speculated on the possibility of using a glass bowl or tube filled with water as an artificial lens. In the early 1800s, Young glued a convex glass lens to one end of a tube, filled the tube with water and held the other end over his eye. The device substituted the smooth surface of the glass lens for the irregular surface of his astigmatic cornea and improved his vision. Contact lenses work on a similar principle.

In 1827, Swiss physician A. E. Fick published a report of the first successful fitting of contact lenses to protect the eyes of a man with cancerous eyelids.

By the early 1930s, contact lenses to improve vision were made of glass and completely covered the exposed part of the eyeball. Heavy and uncomfortable, they could only be worn for short periods of time. Plastic lenses were introduced in the late 1930s. Although they were shatter-proof and lighter than glass, they still covered the entire front surface of the eye and again, could only be worn for a limited time. A major breakthrough came in 1947 with the invention of corneal lenses. These lenses were small, thin and lightweight, and could be worn for hours at a time. Tinted lenses to change eye color were introduced in the mid-1960s, and soft lenses became available in 1971.

Today more than 12 million people wear contact lenses. Improvements in technology continue, and recent developments include bifocal and disposable lenses.

Cupping Devices
Cupping is an ancient form of treatment used to draw blood to the surface of the skin. A small vessel is heated and applied to the skin. When it cools and the air inside contracts, a partial vacuum is created, causing the skin to be sucked into the vessel. This produced a circular area of inflammation. Believers in this form of treatment considered the inflammatory response to be therapeutic.

6. Cupping device in use