Kodak Type Research Articles

Demonstration of the effect of irradiation on canine bowel using in vivo photographic magnification angiography.

THE in vivo angiographic study of smaller blood vessels to various organs under both normal and pathological conditions has been the subject of much recent work and interest. Utilizing a technic of in vivo photographic magnification angiography (1), we have studied the effects of large doses of radiation (1,500 or 3,000 R in a single dose) upon short segments of canine bowel. The presentation of the angiograms obtained with this technic, including a correlation of the in vivo angiographic findings with in vitro injection studies of the irradiated bowel and with the gross and microscopic pathological findings, forms the basis of this report. Method In vivo photographic magnification angiography of the canine bowel has previously been described in detail (1). Basically, it requires surgical mobilization of the intestine of the dog, the use of direct object-film contact radiography by placing a loop of the bowel directly on fine-grain industrial film, and the performance of angiography in this fashion. A red Kifa catheter is placed selectively in the superior mesenteric artery via percutaneous passage through the femoral artery. The abdomen of the dog is opened and a loop of the bowel is mobilized, marked by sutures in the serosa, and bathed in saline in a Bakelite tray. Kodak Type M industrial film is placed under the tray to achieve essentially object-film contact radiography. Eighteen milli-liters of meglumine diatrizoate (Renogra-fin-60) is injected into the superior mesenteric artery via the catheter, utilizing a pressure injector (10 ml/sec.). Radiography is performed, using a fractional focal spot tube if available. An “arterial phase” is obtained by taking an exposure following injection of the contrast medium. A “venous phase” is obtained either by quickly changing the film manually and taking a second exposure or by performing a second injection and obtaining the exposure two to three seconds after completing the injection. The resulting radiograph has sufficient detail and clarity to be photographically magnified up to 10 × as desired. It is important that the bowel be handled gently, with no undue stretch on the mesentery, and kept moist whenever it is outside the body. This can be accomplished by keeping the bowel bathed in warmed, normal saline in a Bakelite tray during angiography and while being irradiated (Fig. 1). Twenty-three adult dogs weighing 16-20 kg were used in the study. Control angiography was initially performed in two widely separated sections of the small intestine of each dog. These portions of the bowel were then irradiated. One segment received a surface dose of 1,500 R in one exposure; the other segment received 3,000 R, administered by a Picker Vanguard unit with the following factors : 280 kVp, 20 rnA, TSD = 40 cm, 1.94 mm Cu filtration, output per minute, 150 R/surface dose.

Characteristics of the Agfa-Gevaert Type 10E70 Holographic Film

The major sensitometric properties of a new holographic film, Agfa-Gevaert type 10E70, have been measured. To facilitate comparison, the same properties have been measured for Kodak type 649-F emulsion. Both the density vs log exposure and time vs gamma curves have been plotted for both films. The relative ASA speed of the Agfa emulsion was also calculated. It was concluded that the relatively high speed and high contrast of this film make it an excellent recording material in holography and optical data processing.

A new mammographic technic.

None of the published technics for mammography take full advantage of the compressibility of the breast. Maximum compression reduces tissue thickness, permitting minimal exposure for a given film type, and provides more nearly uniform thickness. Technic A device (Fig. 1) has been built for compressing and filming the breast in the vertical position, thus utilizing gravity to pull the largest possible portion of the breast over the film (1). The device consists basically of two Plexiglas sheets, one fixed in position and the other movable, between which the breast is suspended and compressed. The film, in a paperholder, is placed between the breast and the fixed Plexiglas which serves as a support. The movable sheet of Plexiglas provides the compression and locks in position. The film is exposed through the compressing sheet by the horizontal x-ray beam. There are several refinements on this home-made device such as a foam-rubber pad on the support, a removable lead blocker for dividing the film, and permanently fixed lead markers. A sheet of lead affixed to the support shields the patient's abdomen in the cephalocaudal position. Films are exposed routinely in the cephalocaudal (Fig. 2) and lateral-medial (Fig. 3) projections. The device sits on the x-ray table and need not be moved for any view. For the cephalocaudal view, the patient stands at the foot of the table, facing the tube, bends forward until the chest rests on the support, suspends the breast between the Plexiglas sheets, and continues to bend until the chest wall above the breast is resting on the movable sheet. The tube is positioned with the central ray at the top edge of the movable sheet. Compression is applied, the patient's head turned and raised as much as possible without raising the chest, and the exposure made. For the lateral-medial view, the patient stands at the side of the table and bends forward and suspends the breast between the Plexiglas sheets. In this position the arm is extended to bring the axillary fold in line with the breast. The film is divided into two sections, the upper portion exposed, the lower section shielded. Two exposures are thus obtained on a single film (Fig. 4). Where the breast is too large, the lead shield is removed and the entire film is used. Excellent quality radiographs have been obtained with Kodak Type M film using 200 mA, 3 seconds, 32 kV at 27-inch distance, no filter. A semicircular cut-out in a lead diaphragm is placed in the filter slot, blocking out the unused upper portion of the beam. Motion has not been a problem. Discussion The technic of breast compression for mammography is simple, fast, and accurate, and a high degree of reproducibility has been achieved. Oblique views become feasible. Flattening of the breast enhances penetration of the base (Fig. 4).

The "point-source" irradiated canine kidney. Angiographic and pathologic evaluation.

In 12 of the 17 dogs used in this investigation the kidneys were subjected to “point-source” irradiation. The experiment was designed to evaluate (a) the relative irradiation sensitivity of renal parenchymal components and (b) the relative role of direct action of radiation as opposed to the indirect effect of vascular damage and interstitial fibrosis in the pathogenesis of irradiation nephritis (1–4). The 198Au grain has an isodose pattern approximating a sphere except within 1 cm of its center; at greater distances the approximation is highly reliable. Kidneys were exposed to such grains, and serial angiography was performed, demonstrating parenchymal and vascular changes. Gross pathologic, histologic, and microangiographic findings were correlated with the in vivo angiographic record. Material and Methods Seventeen mongrel dogs, each weighing 16–20 kg, were used in the experiment (Table I). With few exceptions the procedure was standard as follows 1. All dogs were anesthetized in the usual manner with pentobarbital sodium (Nembutal). 2. A No.7 Rodriguez Alvarez catheter was introduced into the aorta via the distal superficial femoral artery. 3. The catheter tip was placed at the level of the more cephalad renal artery. Twenty to thirty cubic centimeters of methylglucamine diatrizoate (Renografin-76) was mechanically (Cordis) injected at 200 psi, and with rapid serial filming (Franklin) a control aortogram was obtained. 4. a. In 12 animals an end-hole opaque polyethylene catheter (red Kifa) was selectively placed in the renal artery. A standard gold grain (2.5 X 0.7 mm) of known intensity was placed in the stopcock receptacle, then flushed through the catheter by manual injection of 3–4 cc sterile saline. 5. b. In the remainder of the animals gold grains were placed upon the renal capsule or within the parenchyma by percutaneous implantation. 6. Controls were established in each group (4a, 4b) by implanting nonradioactive but otherwise similar gold grains. 7. Aortography was repeated immediately following intra-arterial or percutaneous implantation of the grain. Seventy-two serial angiographic examinations were performed with the catheter being introduced into successive segments of the femoral artery, each segment proximal to the last one used. Selected dogs were anticoagulated terminally, and the kidneys prepared for microangiography after the technic described by Rubin (5, 6). After fixation in 10 per cent formalin the kidneys were sectioned in either the sagittal or the transverse plane but always through the site of the gold grain. One sectioned surface was then utilized for histologic and the other for microangiographic evaluation. The absorbed dose at any point of such a planar tissue section may be calculated, provided the section courses through the site of the irradiation source. Microangiographs were exposed on Kodak type R film or high-resolution glass plates with an industrial radiographic unit (Faxitron 804) having a 0.5-mm focal spot and beryllium window.

Serial radiography of virus-induced osteosarcomas in mice.

Serial radiography has provided us previously with information on the latent period, site of origin, and rate of growth of radiation-induced osteogenic sarcomas in mice (1, 2). We are now using the same technic to investigate the growth and development of osteosarcomas in mice inoculated soon after birth with FBJ virus. This virus was first obtained from a spontaneous osteosarcoma of the thoracic spine of an untreated CFl/Anl mouse (3). An extract of that tumor was injected into 5 mice on the day of birth, and in 2 of them osteosarcomas of the spine developed nine and eleven months later. An extract of the tumor appearing at eleven months was injected into 31 newborn mice, and by nine months bone cancer had developed in 12 of the 24 that survived to weaning. Since that time the oncogenic agent has been transferred by inoculating newborn mice with tumor material that has passed through a 0.45 micron, HA type millipore filter. The fact that electron microscopy demonstrates viral particles both in cellfree extracts and in ultrathin sections of the osteosarcomas (Fig. 1) further supports the opinion that these tumors are indeed caused by a virus. Materials and Methods For the present study 87 CFl/Anl mice received 0.1 ml of cell-free filtrate from virus-induced osteosarcomas soon after birth by intraperitoneal or subcutaneous injection. They have been examined radiographically one to three times a week since they were one day old. Sixty-four of the mice survived to weaning. To increase the number of potential tumors, 28 mice inoculated with FBJ virus at birth were added to the serial radiographic series when they were forty days old, and 14 were added at eighty-six days of age. At the present time there are 37 osteosarcomas among the 106 animals. Ventrodorsal radiographs are taken with the unanesthetized mice held in position by clips extending from the feet to the four corners of a rectangular frame. A beryllium-window rotating anode x-ray tube with 0.5 mm and 1.5 mm focal spots is used without filtration. Kilovoltage varies with the size of the animal, 15 kVp being used for newborn mice which weigh about 1.3 g, and 35 kVp being used for mice weighing 30 g or more. Target-to-film distances range from 12.5 to 15 in., and times from three-twentieth to one second. Living mice are radiographed at 200 mA with larger focal spot; after death 50 m A and the smaller focus are used. No-Screen x-ray film gives good results, but Kodak Type AA Industrial film is far superior for these studies. The air dose for typical exposures on AA film is 1 to 5 R, but we felt that in the present experiment exposures of this magnitude would not jeopardize the results. Ten control mice radiographed repeatedly under the same conditions as the virus-treated mice have not shown any ill effects to date. Radiologic Findings and Discussion

A plutonium particle size study in production areas at Rocky Flats.

Abstract Particle size analyses of 16 air samples obtained during maintenance operations which caused high airborne concentrations of plutonium in chemistry and fabrication plants are reported. The air samples showed an average mass median diameter (MMD) of 0.884 micron and an average count median diameter (CMD) of 0.213 micron. The average geometric deviation () was 2.02. Particle size spectra obtained during simulation of two personnel inhalation incidents showed MMD's of 4.1 ( = 2.36) and 1.2 ( = 1.84) microns. All analyses related the number of alpha tracks on Kodak Type A personnel neutron film to the size of PuOs or PuF4 particles on membrane filter paper.

Autoradiographic Patterns of Methionine-2-14C and Methionine-Methyl-14C in Tissues of the Adult Rat

Using Kodak Type A autoradiographic plates, autoradiograms were prepared of 20 to 25 tissues from adult male Wistar rats killed 4 and 24 hours after feeding methionine-2-14C and 24 hours after feeding methionine-methyl-14C. The autoradiographic method used permitted the viewing on the same slide of the tissue alone, the autoradiogram alone and the tissue superimposed on its autoradiogram. With the exception of bone, all tissues produced autoradiograms at both time intervals; however, the 4-hour autoradiograms were much less intense than those produced after 24 hours. Epithelial tissue and bone marrow produced very intense autoradiograms. Muscle and connective tissue exhibited little activity. The uniformity of labeling observed when methionine-2-14C and methionine-methyl-14C were fed is interpreted to reflect the broad distribution of methionine and its metabolites in tissue proteins and other macromolecules rather than the existence of selective priority sites for compounds formed from its methyl or α-carbon moieties.

MAMMOGRAPHY AS A SCREENING EXAMINATION IN BREAST CANCER.

DOUTINE mammography was performed ft as a screening test for cancer in 3,891 women at a cancer detection clinic. On careful physical examination the breasts were considered normal, but 16 carcinomas were discovered and proved, a rate of 4.11 per 1,000. In 14 of these 16 cases (87.5 per cent), no evidence of metastatic disease was found in the axilla at the time of mastectomy, and an improved prognosis resulted. The roentgenographic examination is easily performed and interpreted, and these findings illustrate the frequency with which carcinoma in an early stage is missed by routine physical examination. Material The women attended the Yates Cancer Detection Clinic voluntarily and represented all economic and racial group.s of the Detroit metropolitan area. The physical examinations were performed by members of the Faculty of Wayne State University School of Medicine. Admittance to the study required that the subjects be forty-six years of age or more and asymptomatic as to breast disease; the breast must be normal on physical examination. Seventy per cent of the patients were between forty-six and sixty years old (Table I); 75 per cent were postmenopausal (Table II). Previous biopsies had been obtained in 8.35 per cent, and in 7.5 per cent there was a family history of breast cancer. The examining physicians were informed of the study and asked to be particularly careful in performing the examination. In addition, with the intention of maintaining their constant alertness, each time an occult cancer was found and proved, this fact was publicized. All mammography was performed at the Woman's Hospital with the lowkilovoltage technic described by Egan (1), with a few changes thought to offer advantages (Table III). An axillary view was not made as a separate exposure; the film for the lateral projection was placed to include the axilla as well as the breast. A long flat-sided cone was employed because with it efficient collimation limited the x-ray beam to the breast and the technician was helped in positioning the patient. The parts to be examined vary in thickness so that a good film of the anterior third of the breast frequently results in an underexposed chest wall or axilla. To permit adequate filming with only one exposure, two films of varying speeds—DuPont #506 and 510 or Eastman Kodak type M and AA—were employed simultaneously, one on top of the other. Dosimetry studies revealed an average of 3..5 to 4.5 rads at the entrance ports for the total examination; the dosimeters were left in place for both views (6). Roentgen Diagnosis In reading the films, the diagnosis was given as malignant, suspicious, benign, or normal. The rates of occurrence are tabulated in Table IV.

MAMMOGRAPHY: REPORT ON ITS USE IN WOMEN WITH BREASTS ABNORMAL AND NORMAL ON PHYSICAL EXAMINATION.

This paper is a presentation of the roentgenographic findings in benign and malignant diseases of the breast, showing (a) the results of mammography in 2,000 women with breasts abnormal on clinical examination and (b) the preliminary results of a screening program. The use of mammography was limited until Egan (1) reported his experience in 1,000 examinations (634 patients) at the M. D..Anderson Hospital and Tumor Institute, Houston, Texas. Only sporadic reports appeared in the literature following its popularity in the early 1930's, Gershon-Cohen (2) contributing many articles on the examination and Leborgne (3) publishing his important observations of tumor calcifications. Technic The technic employed in this study was much like that described by Egan: low kilovoltage, high milliampere seconds, unfiltered x-ray beam, and industrial x-ray film (Table I). Two changes are considered to offer distinct advantages. No axillary view was obtained. It is necessary to include all the tail of the breast which can be accomplished readily on the lateral view; this roentgenogram shows the main breast mass, portions of the chest wall, all the tail and the contents of the axilla. The thickness of the soft tissues encountered differed considerably, and this was allowed for by the use of two films simultaneously during the exposure—Eastman Kodak Type M and AA. The M film permits an adequate roentgenographic image of the main breast mass. The AA film gives proper exposure of the tail of the breast, contents of the axilla, and structures near the chest wall. It also results in an overexposed image of the breast itself, which is frequently of some value. The cephalocaudad projection of the breast was obtained in the usual manner. Dosimetry Measurements of the dose received in small-and large-breasted women were made with entrance and exit determinations, including the axilla for each view. The dosimeters, of thermal luminescent lithium fluoride (Fig. 1), were also left in place during both exposures. The results were then averaged between the small and large breasts, and the difference between them approximated 25 per cent at the entrance ports. All figures are in rads except when specified as millirads. It is significant that depletion is nearly complete within the breast: 3.19 r entrance dose on the cephalocaudad projection with 150 mr exit dose. There is only one area of overlapping exposure; this is in the upper medial quadrant. Classificanon A classification of the patterns of benign and malignant disease as seen on the roentgenograms is of value. It must be approached, however, with the knowledge that the radiologist can duplicate the morphologic terms of the pathologist only up to a point. Benign Conditions The radiograph will usually reveal a dominant pattern of a benign condition of the breast. For convenience, two great groups may be recognized: mammary dysplasia (generalized and localized) and miscellaneous.

Conclusions from the Characteristic Curves of Photographic Plates, Minimum Effect of Grain*

By a consistent argument, based on the characteristic curves of photographic plates, the optimum conditions for the following spectrographic problems are derived: weak emission line without background; weak absorption line; weak emission line on a given continuous background; prefogging; measurement of relative intensities. The effect of the grain on the resolving power is minimized by averaging over the length of the line. This technique gives to the very sensitive plate (Kodak type I-O), in spite of its coarse grain, the same high resolving power as that of a very fine grain plate which requires a 90 times longer exposure.

Radiation induced by Alpha-Particles in Thin Films

WE have examined spectrographically the light emitted by thin films bombarded by α-particles1. The films were built up by evaporation on quartz slides to a thickness small compared with the range of the α-particles. The slides were mounted in front of the slit of a Hilger f/4 quartz spectrograph and exposed to a 25-mC. polonium source. Representative spectra, photographed on Eastman Kodak type II-0 spectroscopie plates, are shown in the accompanying photograph.

The Spatial Photographic Recording of Fine Interference Phenomena*

Interference bands as close together as 0.4μ were recorded with the Kodak Type 548 Spectroscopic Plates. The penetration of these bands into the emulsion layer was detected by microscopic examination of a vertical section of the photographic record. The photographic record of such bands, the spacing between which depends only upon the angular tilt of a Lloyd mirror and the wave-length of the radiant energy being used, should prove useful as a stage micrometer. Since these photographic records behave as diffraction gratings, the spacing between the band images was checked by measuring the diffraction angle, using radiant energy having a wave-length shorter than the spacing.