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J S Krohmer

Publications and source records attributed to J S Krohmer.

7 recordsLinked to original sources
PubMed1989

Radiography and fluoroscopy, 1920 to the present.

A survey of radiological procedures carried out in 1980 by J. L. Johnson and D. L. Abernathy indicated that of the 181 million procedures performed in that year, there were 77.5% plain radiographic studies, 12.7% contrast studies, 4.0% sonographic studies, 3.2% nuclear medicine studies, 1.8% CT studies and 0.8% special vascular procedures and cardiac catheterizations. Note that over 90% of all the studies were of the "conventional" type and that fewer than 2% were CT studies. In the early 70's when CT was introduced, it was predicted that it would soon take over most of radiography; some 7 or 8 years later, it was obvious that this would not take place. According to Tanako of the Fuji Photo Film Co. Ltd., conventional radiography has resisted being pushed aside because of its very high information content: 4-6 megabytes per image. A CT image contains about 0.5 megabytes. If a system is to take over from conventional radiography, it will have to overcome this large difference in information content. Digital or computed radiography seems capable of this, but probably not for some time (perhaps, 10 or 20 years). It seems unlikely that there will be much change, except for refinement, in the image intensified fluoroscopy equipment used for observing dynamic processes, and it will probably not be replaced. Another situation which will preclude the rapid demise of conventional radiography is financial inertia: There is between 5 and 10 billion dollars worth of diagnostic equipment in hospitals in this country and significant amount more in private offices and clinics. It is true that the amount has diminished in recent years, but this has been more because of DRG's than because of "takeover" by new modes of imaging. It is not likely that this investment will be given up quickly or easily. One must also keep in mind that the film digitization and the photostimulable phosphor digital systems, described above, do use existing radiographic equipment, and the image intensification system uses a great portion of existing fluoroscopic equipment, therefore "going digital" may not require complete replacement of existing equipment.

Fluoroscopy↗
PubMed1983

The effect of irradiation in the therapeutic dose range on vascular-graft material.

Samples of Dacron and Teflon tubing that were obtained from unused vascular-graft remnants were irradiated with 1000 to 8000 rad (10 to 80 Gy) and compared in tensile strength and elongation with unirradiated specimens. No significant difference in these parameters was found. These levels of single-dose irradiation may be assumed to be similar to those used in fractionated irradiation of human malignant neoplasms. Therefore, it can be concluded that irradiation at clinical dose ranges does not affect the tensile strength and elongation of vascular graft material. Polyethylene tubing, on the other hand, is strengthened to a minor degree by single dose irradiation with 1000 to 8000 rad (10 to 80 Gy).

Blood Vessel Prosthesis↗
PubMed1981

X-ray doses to patients undergoing full-spine radiographic examination.

Patients undergoing full-spine radiographic examinations receive x-ray doses of 115 mrad (1,150 microGy) to 85% of the body's total active bone marrow, 235 to 465 mrad (2,350 to 4,650 microGy) to the breasts, 165 mrad (1,650 microGy) to the embryo and ovaries, and 700 mrad (7,000 microGy) to the thyroid. These doses can be doubled for patients exposed to the x rays before and after treatment.

Female↗