Paul Hodges is an extraordinary individual. He was born, before Röntgen's discovery, on January 6, 1893, the son of a physician who worked in partnership with Paul's uncle, Dr. William Rinehart, at the Rinehart Hospital in Ashland, WI. Paul's father died in 1901 at the early age of 36, due to septicemia from a finger infection acquired while performing an autopsy, and Uncle Will gradually became Paul's surrogate father.
Radiology began to be practiced at Rinehart Hospital in 1897. Their first X-ray machine used a German induction coil with mechanical interrupter and a small X-ray tube similar to that used by Röntgen. This device sputtered away in the front office during Paul Hodges' early childhood. At age fourteen, Paul became an apprentice in the hospital, which by that time had been equipped with more powerful X-ray equipment. There he learned how to prepare the chemical solutions used in "X-ray photography."
Hodges studied physiology at the University of Wisconsin before completing his M.D. degree in 1918 at Washington University in St. Louis. There he taught physiology to nurses. He also worked with his medical school roommate, Herbert Gasser, who in 1944 received the Nobel Prize with Joseph Erlanger for measuring and classifying nerve-fiber conduction. That work had defied their efforts as long as the only available recording device was the quartz fiber galvanometer, but yielded when they used instead, the electron stream of a Brown tube. Hodges also served as a laboratory assistant to Erlanger and Gasser in their animal experiments aimed at the treatment of surgical shock by the IV injection of sodium arabate to replace lost blood. In 1918, Dr. Hodges became a commissioned officer in the army and was stationed at the X-ray School in Camp Greenleaf, GA. After the war, the University of Wisconsin granted Dr. Hodges a B.S. degree in 1919 and a Ph.D. in Physiology in 1924. Dr. Hodges began practicing radiology in China. The Rockefeller Foundation through its China Medical Board had made a major commitment to build and operate the Peking Union Medical College. Dr. Hodges was recruited in 1919 as a roentgenologist and remained there until 1927 when he became professor and chairman at the University of Chicago. Hodges' remarkable education and experience prepared him well for the leadership role in radiology that he was destined to play. This appointment, which began as a 1 year sabbatical leave became a 31-year career.
Dr. Hodges created a research-oriented department at the University of Chicago that focused on three main areas: improved X-ray systems for subspecialty applications, improved film development facilities, and novel ancillary hardware, such as a photo-timing exposure control. For these purposes, Dr. Hodges established a machine shop, unique in its time, that was devoted exclusively to radiology and employed a full-time staff that eventually grew to five machinists. Although hot-cathode X-ray tubes had completely replaced the gas variety by 1927, they were not shock proof, had no inherent X-ray shielding, were not line-focused, and of course did not have rotating anodes. The only high-voltage rectifiers were rotary switches driven by synchronous motors; neither the hot cathode nor the solid-state high-voltage rectifier had been invented. Exposure time switches were of poor quality, and means for determining X-ray tube voltage and current were far from satisfactory.
The concept of an X-ray department with special machines for examining specific regions of the body did not appeal to manufacturers of the day. They produced simple equipment for radiologists working in limited space -- often in downtown office buildings -- and needing a single machine capable of every type of examination. Dr. Hodges was not able to convince them that their equipment was inefficient and produced suboptimal images, so he proceeded to manufacture his own at the University of Chicago. He designed and had built, in the department shop, equipment dedicated to the skull, chest, upper gastrointestinal, colon, and kidney examinations. As early as 1920, Dr. Hodges had improvised a head table that later went through numerous improvements in the radiology department's machine shop, resulting finally in a versatile model that was produced commercially for many years by one of the department's former machinists, Angrabright. It was known as the Hodges Head Stand.
Under Hodges, most of the department's plain film examinations, such as those of the chest, abdomen, and axial skeleton and pyelograms, were stereoscopic. Carefully calculated tube shifts, with two exposures for each projection, produced images of exquisite quality when viewed on the stereo viewers that were present throughout the department.
To meet the needs of Fred Templeton, a pioneer in gastrointestinal radiology, Hodges designed a spot-filming fluoroscope. Four images could be quickly and easily exposed on one 7x17 inch film. In its final form, this device was highly satisfactory except for one weakness: the X-ray tube. Shock-proof tubes with cables were available by this time, but these tubes invariably failed after a few hours of fluoroscopy at 3 mA and a dozen or more spot films at 50-100 mA. The problem was thought to be solved when water-cooled jacketed tubes were adopted, but it was never really overcome until shock-proof rotating anode tubes became available. With the assistance of the 3M Company, the department also developed improved compounds for attaching jacks to the ends of high-voltage cables. Special equipment was designed as well for double-contrast examinations of the colon and for pelvimetry and fetometry.
The processing of large numbers of X-ray films was a difficult business until the Eastman Kodak Company invented and finally perfected hangerless processors, which received exposed film and, a few minutes later, delivered the films processed and already dry. One of the first of these units was installed at the University of Chicago. Radiologists who recall film developer stains on their fingers and clothing, as well as films that were never properly developed, understand the extent to which the automatic film developer revolutionized radiology.
Before modern processors became available, Dr. Hodges and his staff designed and redesigned tanks and conveyors, dryers, and means of replenishing and temperature-controlling film developing solutions. Now much is taken for granted, including the recording of patients' names and numbers on film before processing. At this time, however, it was common to depend on lead numbers, which the technician taped on the cassette for identification when the examination was performed. That system had many flaws, and in a busy X-ray department, the matching of patient and film was difficult, often causing serious delays between exposure and reporting. The Hodges team developed a unique film-identification device that recorded the patient's unit number, the number of the examination, the number of the film within the specific examination, and the date on the film by use of a small X-ray machine with a dental X-ray tube. This system preceded by more than 30 years the "flash card" system that was later introduced commercially.
In the 1920s, Hollis Potter invented and published a report of his moving grid, which revolutionized the X-raying of thick body parts; Paul Hodges' team added an important improvement by making it reciprocate. A color-coded film-jacket identification system for film filing, adapted from the international color code for electronics, was developed by Hodges long before such a system became universal. Because he had little trust in any commercial product, Hodges also developed unique barium mixtures for colon and upper-gastrointestinal examinations and was innovative in flavoring the latter with a commercially produced chocolate from Nestlé. These mixtures were prepared in the hospital pharmacy from bulk barium and anticipated by almost 50 years the commercially prepared barium mixtures that are now designed specifically for single- and double-contrast examinations. The relatively dense barium products for colon examinations were mixed in a commercial paint mixer before use in the department's colonoscopy room.
Dr. Hodges had long believed that it should be possible to record the amount of radiation used in an examination. At his urging, Russell Morgan, a member of the department who had a substantial engineering background, tackled the problem and solved it almost immediately with an instrument that Dr. Hodges insisted be called the Morgan Exposuremeter. Fortunately Morgan did not stop there, but went on to design circuits that would automatically meter out just enough radiation for a satisfactory image; these devices became known as phototimers [2, 3]. He also developed automatic collimation and a spot-filming device for fluoroscopy. Morgan further refined and perfected these ideas after he moved to Johns Hopkins.
Clinical research flourished in the department during the Hodges era [4, 5]. Orthopedic surgery, gastroenterology, and gastric surgery had long been noteworthy at the University of Chicago, and this affected radiology. Dallas Phemister, chairman of the surgery department, was a recognized leader in orthopedics and at that time exceeded most radiologists in his knowledge of the radiology of bone disease. Working with Phemister, Hodges published "X-Ray Diagnosis of Diseases of Bones and Joints," a classic loose-leaf text that included pathologic correlation. Several other University of Chicago radiologists published extensively in a variety of areas. Fred Templeton became a leader in gastrointestinal radiology, working closely with Drs. Walter Palmer and R. Schindler, the latter the inventor of the gastroscope. Templeton's book on gastrointestinal radiology was one of the first, if not the first, devoted to that topic [6]. An important contribution of this text was its correlation of radiologic and clinical findings and its standardization of gastrointestinal examinations, thereby permitting reliable evaluation of disease progression over time. With his faculty, Dr. Hodges also prepared comprehensive manuals for professional and nonprofessional staff that described the x-ray equipment in the department and how it should be used. These remarkable texts reflect the high standards and compulsive attention to detail that were characteristic of Hodges and his faculty.
Paul Hodges played a key role in creating the Association of University Radiologists, which was formed at the University of Chicago on May 23, 1953. The organizational meeting was called by Hugh Wilson of Washington University, by Paul Hodges and his brother Fred Hodges, chairman at the University of Michigan, and by Russell Morgan, who had moved to Johns Hopkins. Dr. Morgan was elected as the first president; Henry S. Kaplan became president-elect, and William B. Seaman the secretary/treasurer.
Many honors came to Dr. Hodges. Among the most significant are the Caldwell Medal of the American Roentgen Ray Society (1953), and the presidency of that society (1955-1956), the Cravat of the Order of Brilliant Star, Republic of China (1963), the first Grubbé Medal of the Chicago Medical Society (1964), and the Gold Medal of the Association of University Radiologists (1978). The Radiological Society of North America dedicated its 1992 scientific session in his honor.