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D J Hamlin

Publications and source records attributed to D J Hamlin.

At least 37 records · Page 2Linked to original sources
PubMed1981

Radiologic manifestation of histiocytic lymphoma in the skeletal and central nervous system.

The radiographic manifestation of histiocytic lymphoma in the skeletal and central nervous system of 112 non-selected patients were reviewed in a retrospective study. Histiocytic lymphoma metastatic to bone and brain are late manifestations of the disease occurring in 15 and 4%, respectively. Involvement of the spinal cord and nerve roots is found in 6% and represents often the initial manifestation of the disease. Histiocytic lymphoma of brain presents angiographically as avascular mass without site predilection and on contrast enhanced computer tomography as hyperdense lesion without necrotic center. On myelography an extradural mass or complete block is found. The most common skeletal locations are spine, pelvis, rib and femur. The ratio of multifocal to unifocal skeletal manifestations is approximately 2 to 1. The radiographic appearance varies from completely lytic, often associated with a soft tissue mass, to osteoblastic, often with Pagetoid features. Early recognition of histiocytic lymphoma manifestations is important to guarantee prompt institution of appropriate therapy since the disease can progress extremely rapidly.

Adolescent↗
PubMed1981

Intravenous contrast enhancement in computed tomography of pelvic malignancies.

The value of intravenous contract enhancement in computed tomography (CT) of pelvic malignancies was analyzed in 124 cases. Contrast enhancement of pelvic organs depends on the smooth muscle component and the administered iodine dose. Contrary to parenchymal organs in the abdomen the iodine washout from smooth muscle organs is slow. A rapid (approximately 5 minutes) intravenous infusion of 300 ml diatrizoate 30% followed immediately by scanning of the area of interest was found optimum to improve the CT visualization of tumors in all pelvic organs with the exception of the prostate. Depending on the organ to be investigated the intravenous contrast administration has to be combined with retrograde gas insufflation into bladder and/or rectum with insertion of a tampon into the vagina. The described technique is particularly useful for the assessment of early tumor extension beyond the primary organ.

Contrast Media↗
PubMed1981

Computed tomography of the pelvis: sagittal and coronal image reconstruction in the evaluation of infiltrative bladder carcinoma.

The application of reconstructed images in the sagittal and coronal planes is discussed and illustrated with respect to the computed tomographic (CT) evaluation, including staging, of bladder carcinoma. Reconstruction CT was found to be particularly useful in delineating the craniocaudal extent of tumor. In addition, reconstructed images frequently aided the CT evaluation of the relationship of tumor mass to adjacent structures such as seminal vesicles and prostate gland. The improved anatomical orientation achieved by reconstruction was found useful in the presurgical evaluation of tumor site and extent of the lesion.

Adenocarcinoma↗
PubMed1981

Intrathoracic histiocytic lymphoma.

Intrathoracic manifestations of histiocytic lymphoma were reviewed in a retrospective study of 112 nonselected patients who had at least a 2 year follow-up period or had died. In 50% (56 cases), intrathoracic histiocytic lymphoma was found. In 26% (29 cases), intrathoracic manifestations were initially seen. In 11% (12 cases), the disease was completely confined to the chest. Mediastinal involvement was present in 25% (28 cases), hilar involvement in 17% (19 cases), pulmonary involvement in 20% (22 cases) (interstitial or mixed interstitial alveolar infiltrates in 13% [14 cases], nodular lesions in 8% [nine cases], localized homogeneous consolidations 5% [six cases]), and pleural involvement in 18% (20 cases), of which 4% (four cases) had localized pleural plaques. Intrathoracic manifestations of histiocytic lymphoma are similar in the early and late stage of the disease. However, sarcoidlike hilar and mediastinal involvement (3% [three cases]) and a localized mass in the lower posterior mediastinum (4% [four cases]), the anterior mediastinum (2% [two cases]) or unilaterally in a hilum (2% [two cases]) were initial presentations not encountered late in the disease. Because of the rapid progression of this entity, early recognition of its intrathoracic manifestations is mandatory for effective therapy.

Adolescent↗
PubMed1981

Histiocytic lymphoma of the abdomen: radiographic spectrum.

Abdominal manifestations of histiocytic lymphoma were reviewed in 112 patients who had at least a 2-year follow-up period or had died. In 70% abdominal histiocytic lymphoma was found and in 29% histiocytic lymphoma was initially limited to the abdomen. Localized abdominal histiocytic lymphoma presented as (1) intrinsic disease of the stomach, (2) pancreatic/peripancreatic masses, (3) high aortic lymphadenopathy, (4) mesenteric masses associated with small bowel infiltration, and (5) intrinsic ileocolic masses. When all patients with abdominal histiocytic lymphoma are considered, computed tomography was positive in 87%, lymphography in 86%, upper gastrointestinal barium examination in 50%, excretory urography in 38%, and barium enema in 25%. The extent of abdominal histiocytic lymphoma was more accurately assessed with computed tomography than any other radiologic examination including lymphography. Computed tomography seems to be the radiologic examination of choice in the staging of abdominal histiocytic lymphoma; the other examinations should be used when specific symptoms are present or when the computed tomographic findings are equivocal.

Abdominal Neoplasms↗
PubMed1981

Contrast enhancement in abdominal CT: bolus vs. infusion.

The accuracy of in vivo iodine estimations by CT in the aortic blood was determined in the dog. Iodine wash-out curves of five patients each receiving either a bolus of 100 ml diatrizoate 60% or a 10 min infusion of 300 ml diatrizoate 30% and 138 nonenhanced abdominal CT scans with various lesions in 104 patients were analyzed. This investigation suggests: (1) In vivo estimations of iodine concentrations are subject to considerable variation. (2) Iodine accumulation and wash-out for a given contrast administration mode are similar in liver, spleen, and pancreas with tissue iodine concentrations always below blood iodine concentrations, while a significant iodine concentration above iodine blood levels is found in the renal parenchyma. (3) If contrast enhancement is analyzed separately for bolus effect (arteriovenous iodine difference [AVID] greater than 30 H), nonequilibrium phase (AVID 10-30 H) and equilibrium phase (AVID less than 10 H), a good correlation between aortic blood and tissue iodine concentration is found for the latter two phases in the kidney, liver, and spleen which is independent of the contrast administration mode. (4) Visualization of all focal (cystic and solid) lesions is improved in the kidneys after contrast enhancement, while in the other investigated abdominal organs only cystic lesions are always better visualized on the enhanced scan regardless of contrast material dose, administration mode, and time of scanning. (5) Improved visualization of a solid lesion in liver, spleen, and pancreas is most likely achieved by scanning during bolus effect and the nonequilibrium phase, that is, within the first 2 min after a contrast material bolus or during a contrast material infusion. The chance to conceal a lesion in these organs increases significantly when performed at a later stage after contrast administration, that is, in the equilibrium phase.

Animals↗
PubMed1981

CT of intramural endometrial carcinoma: contrast enhancement is essential.

The accuracy of computed tomography (CT) in recognizing early stage endometrial carcinoma was assessed in a prospective study in 10 patients in whom macroscopic and microscopic findings of the surgical specimen were correlated with the CT findings. In no instance was endometrial carcinoma confined to the uterine wall demonstrated on a precontrast examination. However, after intravenous infusion of 300 ml diatrizoate 30%, all seven carcinomas involving one-third or more of the thickness of the uterine wall were clearly demonstrated as hypodense lesions. In three patients the center of the hypodense lesions was significantly more enhanced and this was found at surgery to represent less necrotic tumor. Three carcinomas with lesser intramural extent were still invisible after contrast infusion. Because of slow contrast material accumulation in the myometrium and a delayed washout, the optimum time for scanning appears to be immediately after termination of the infusion when the bladder is not yet densely opaque since this may cause disturbing artifacts. The depth of myometrial invasion by endometrial carcinoma is an important prognostic factor in the disease and the CT demonstration of tumor extent may prove to be valuable in optimizing the selection of surgical and/or radiotherapeutic procedures.

Adenocarcinoma↗
PubMed1981

Attenuation and contrast enhancement of gynecologic organs and tumors in CT.

CT scans were obtained of 11 normal women and 34 women with gynecologic tumors. Twenty-three of 26 women with known malignant tumors had abnormal CT scans while all control patients had normal. The tumor extent demonstrated by CT correlated with either pathologic or surgical staging in 78%. Contrast enhancement increased the diagnostic yield and accuracy of staging. Attenuation values of the normal uterus and uterine tumors are quite similar prior to contrast medium. After administration of contrast agent the normal myometrium attenuation values increase more than other pelvic tissues. Uterine tumors show substantially less enhancement and show a greater variation of density throughout the tumor than normal myometrium. Density readings are not predictive of histologic type or tumor grade. Tumor was best detected and its extent best seen after high doses of intravenous contrast medium infusion, which should be considered a routine part of the diagnostic evaluation of these patients.

Contrast Media↗
PubMed1980

Modification for computerized tomographic staging of infiltrative bladder carcinoma.

Technique modifications for computed tomographic staging of infiltrative bladder carcinoma are aimed at maximizing image quality and reducing artifactual problems, particularly those associated with the effects of motion owing to poor patient cooperation. Patients unable to tolerate a lengthy procedure or the prone position have been studied using a low density contrast technique with controlled bladder distension. Although the intravesical tumor component often is not as dramatically demonstrated as with the gas insufflation technique the accuracy of both staging procedures appears to be high. The tendency towards overstaging is common to bladder opacification and gas insufflation techniques but this may be reduced considerably by bowel opacification when necessary and the use of intravenous contrast enhancement techniques.

Aged↗
PubMed1980

Upper extremity contrast medium infusion in computed tomography of upper mediastinal masses.

Infusion of dilute contrast agent through an upper extremity vein results in marked opacification of the superior vena cava and the ipsilateral subclavian and brachiocephalic veins in computed tomography of the upper mediastinum. Also, the cranial arteries are well opacified. Images obtained by this method display anatomical relationships to better advantage and permit more accurate interpretation of anatomical relationships of the upper mediastinal masses. Improved anatomical details are obtained as compared to noncontrast scans or scans after bolus injection. In cases of suspected venous occlusion, functional diagnostic information is also achieved.

Contrast Media↗
PubMed1979

Computed tomography of bladder: staging of bladder cancer using low density opacification technique.

In the course of computed tomographic (CT) evaluations involving 200 patients with suspected pelvic disease we have found that scan quality is often suboptimal. A preliminary report employing a low density bladder opacification method is presented whereby an indwelling catheter is inserted to control bladder volume and facilitate the instillation of low density iodinated contrast agent (0.6% Renografin-60). The patient remains supine throughout the twenty-five-minute procedure. Observations during the CT staging and follow-up of a controlled group of 8 patients undergoing immunotherapy and/or radiation therapy for bladder carcinoma indicate that this is a simple, safe, and effective staging procedure. We have obtained reliable clinical-radiologic-pathologic corrlation as a result of careful surgical staging and biopsy, followed by open surgery and full pathologic examination. It is hoped that this information will help initiate other similar studies to determine the diagnostic accuracy of this method and thus its use in pretherapeutic evaluation of the bladder lesion and its subsequent response to treatment.

Aged↗
PubMedDate not supplied

Computed tomography of uterine papillary serous carcinoma.

We describe the CT appearances of a fairly commonly encountered "special variant" carcinoma of the uterine corpus called uterine papillary serous carcinoma ( UPSC ). UPSC closely resembles ovarian papillary serous carcinoma microscopically but CT with contrast can differentiate between these two entities. In addition CT in this patient clearly showed the characteristic spread mode of this particularly aggressive form of endometrial carcinoma. Because UPSC has a significantly higher relapse rate than other histologic types of endometrial carcinoma it is important to recognize it at the time of the CT staging procedure. The spread pattern of UPSC suggests the need for adjuvant irradiation or chemotherapy.

Aged↗
PubMedDate not supplied

Magnetic resonance characteristics of an abdominal desmoid tumor.

A case of desmoid tumor arising from the abdominal wall is presented. Although the mass was well demonstrated by contrast-enhanced computed tomography (CT), the typical fibroblastic nature of the tumor was best depicted by magnetic resonance (MR) imaging which also clearly showed the classic origin of the tumor from the anterior abdominal wall musculature. The overall extent of the lesion was also best demonstrated by MR imaging using both transaxial and coronal planes. Spin echo sequences with late echoes were useful in confirming the nature of this lesion.

Abdominal Muscles↗
PubMedDate not supplied

MR imaging of uterine leiomyomas and their complications.

Magnetic resonance (MR) imaging in eight patients with uterine leiomyomas and in eight normal female volunteers clearly depicted the size, shape, and position of the corpus uteri and demonstrated adjacent anatomic structures to good advantage in transaxial, coronal, and sagittal planes. Spin echo (SE) with short repetition time (TR) and short echo time (TE) values was judged best for overall delineation of anatomic structures. Longer TR and TE times were used to differentiate myometrium from endometrium. Detection and characterization of complications of uterine myomas were facilitated by the use of multislice/multiecho SE techniques, but in general TE values greater than 60 ms were not needed to differentiate endometrium from myometrium and in most cases did not improve the MR depiction of abnormalities. Calculated T1 and T2 relaxation times from this preliminary study do not demonstrate a clear advantage in further characterizing uterine abnormalities.

Adult↗