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T J Welch

Publications and source records attributed to T J Welch.

46 records · Page 3Linked to original sources
PubMed1988

Hemorrhage in major pelvic fractures.

Significant hemorrhage following major pelvic fractures should always be expected. Early recognition of such fractures during the resuscitation of any multiply injured patient is essential before instituting measures that might combat blood loss. In the majority of patients, simple resuscitative measures, including employment of the pneumatic antishock garment, will suffice. With certain types of fracture geography, the early application of external fixation devices may also play an important role. Increasingly popular has been the technique of diagnostic angiography and therapeutic embolization, applicable to approximately 3 per cent of all pelvic fracture patients. With exsanguinating hemorrhage, even the best equipped and most sophisticated major trauma centers can be taxed. The decision whether a patient should be taken directly to the operating room or to the angiography suite remains one of the most difficult for even the most highly skilled trauma surgeon. Patients with rapidly expanding or free rupture of pelvic hematomas noted at the time of celiotomy, or those with large open wounds, usually leave no recourse but to attempt direct operative control, to include even the most morbid option of a life-saving hemipelvectomy or corpectomy. More often, however, once other sources of surgically correctable hemorrhage are controlled or ruled out, diagnostic angiography followed by therapeutic embolization is a mainstay in the modern-day management of pelvic fracture hemorrhage.

Embolization, Therapeutic↗
PubMed1988

Cystic pancreatic tumors: CT and sonographic assessment.

Thirty-five CT scans and 23 sonograms of 45 pathologically proved pancreatic cystic neoplasms (16 microcystic adenomas, 17 mucinous [macrocystic] cystadenomas, and 12 mucinous [macrocystic] cystadenocarcinomas) in 43 patients were retrospectively and blindly reviewed. Radiologic findings and their usefulness in differentiating microcystic from mucinous subtypes were assessed. The number of cysts within the tumors (more than six in microcystic adenomas and six or fewer in mucinous cystadenomas and cystadenocarcinomas) and the diameter of the majority of cysts within the tumor (less than or equal to 2 cm in microcystic adenomas and greater than 2 cm in mucinous tumors) were the most helpful radiologic findings in differentiating tumor types. Calcification was present in 38% of microcystic adenomas, 18% of mucinous cystadenomas, and 8% of mucinous cystadenocarcinomas by CT. Calcification was not definitely identified on any of the sonograms. A central scar was identified in only two (13%) of 16 microcystic adenomas. Blind retrospective review was often able to correctly classify tumors as either microcystic (CT, 93%; sonography, 78%) or mucinous (CT, 95%; sonography, 93%). All tumors with a typical appearance on either CT or sonography were categorized correctly. Cystic pancreatic tumors may be difficult to prospectively separate from other types of pancreatic cysts. Assuming a cystic neoplasm is present, it often can be classified correctly as microcystic or mucinous (macrocystic) by using the above criteria.

Adenoma↗
PubMed1986

Directed intravascular precipitation of bisantrene for pelvic malignant lesions: preclinical studies.

Bisantrene, a clinically active anticancer drug with limited solubility at physiologic pH, was delivered by selective injection into the internal iliac artery of male calves. The percutaneous transfemoral angiographic techniques used in the calves were identical to those used in adult human patients. Directed intravascular precipitation of bisantrene at the maximal tolerable clinical dose for intravenous administration (260 mg/m2) caused severe tissue damage in 5 of 10 animals that received these intra-arterial injections. (One calf in this study group died of unknown causes 10 days after the drug infusion). A reduced intra-arterial dose (50 mg/m2) was used in seven calves, and no local tissue damage was evident on gross or microscopic examination. Nevertheless, resultant concentrations of bisantrene deposited in the ipsilateral bladder wall were 10- to 100-fold those concentrations found after intravenous administration of a dose 5 times higher. These animal toxicology and pharmacology data support initiation of a phase I clinical trial of directed intravascular precipitation of bisantrene in humans. This clinical trial will be developed for patients with advanced refractory cancers of the anatomic true pelvis, such as those originating in the urinary bladder, prostate, rectum, and uterine cervix.

Angiography↗
PubMed1985

Focal nodular hyperplasia and hepatic adenoma: comparison of angiography, CT, US, and scintigraphy.

The authors reviewed 23 cases of focal nodular hyperplasia and 13 cases of hepatic adenoma, all of which were confirmed pathologically. All solitary masses that exhibited normal or increased uptake of technetium 99m-sulfur colloid were shown to be hyperplasia; while previous criteria such as a central blood supply on angiograms or a central scar on computed tomography (CT) or ultrasound (US) scans were helpful, they were relatively infrequent. A mass that was slightly hypodense and homogeneous on a CT or US scan and highly vascular with an intense capillary stain on an angiogram was almost always hyperplasia. Acute hemorrhage within a focal hepatic tumor was common in adenoma but did not occur in hyperplasia.

Adenoma↗
PubMed1983

Pheochromocytoma: value of computed tomography.

A review of 60 histologically proved pheochromocytomas confirmed the value of computed tomography (CT) in the evaluation of this tumor. CT was found to be an accurate means of locating the tumor in 52 patients presenting for the first time and 8 patients with evidence of recurrence.

Adolescent↗
PubMedDate not supplied

Detection of flat lesions in the colon with CT colonography.

BACKGROUND: We investigated whether flat lesions of the colon could be detected on computed tomographic colonography (CTC). METHODS: CTC and conventional colonoscopy were performed on 547 consecutive patients. A subset of 22 polyps was described as flat on colonoscopy (n = 16) or CTC (n = 6) and are the basis of this report. CTC was performed with a standard technique (5-mm collimation, 3-mm reconstruction intervals). Patients were scanned in supine and prone positions. Examinations were randomly assigned and reviewed in a blinded fashion by two of three radiologists. Prospective interpretations were recorded. All patients had conventional colonoscopy, which served as the gold standard. RESULTS: Twenty-two flat lesions ranging from 0.4 to 3.5 cm were histologically classified as adenomatous (n = 8) or hyperplastic (n = 14). The sensitivities for detecting all flat lesions and flat adenomas by each reviewer were 43% and 100%, 65% and 100%, and 15% and 13%, respectively. "Double reading" resulted in detection of 68% of all lesions and 100% of adenomas. Of the seven hyperplastic polyps missed by both reviewers, four were identified retrospectively. CONCLUSION: Flat lesions of the colon represent an important source of false negative CTC examinations. Awareness of their morphology can assist radiologists in finding most of these challenging lesions.

Adenomatous Polyps↗
PubMedDate not supplied

Helical and electron beam CT scanning in the evaluation of renal vein involvement in patients with renal cell carcinoma.

PURPOSE: The purpose of this study was to assess helical and electron beam CT scanning in the evaluation of renal vein involvement in patients with renal cell carcinoma (RCC). METHOD: Seventy-three patients with 76 pathologically proven RCC who underwent surgical resection or autopsy were evaluated for the accuracy of helical and electron beam CT scanning in the detection of renal vein tumor thrombus in patients with RCC. Patients were entered into the study only if they were scanned on either electron beam or helical CT scanners with intravenous contrast medium enhancement. The tumors involved the right kidney in 38 cases and the left kidney in 38 cases, with tumor size ranging from 1.5 to 19 cm (mean 7 cm). The pathologic grade of the tumor was Grade I in 21, Grade II in 37, Grade III in 15, and Grade IV, in 3 patients. RESULTS: The accuracy of preoperative CT evaluation of the renal vein for presence or absence of tumor thrombus was 96%. The negative predictive value was 97% and the positive predictive value was 92%. Sensitivity was 85% with a specificity of 98%. In two cases we were unable to detect small intrarenal venous thrombus, although this was present on a microscopic level and did not affect surgical resection. A single false-positive CT result occurred secondary to unopacified blood flow from a capsular vein into the affected renal vein, resulting in a small flow void on CT. CONCLUSION: The data show that preoperative staging of the renal vein in the patients with RCC is effectively provided with helical and electron beam CT scanning.

Adolescent↗
PubMedDate not supplied

CT characteristics of metastatic disease of the pancreas.

Contrast material-enhanced computed tomographic (CT) scans obtained over a 10-year period in 66 patients with metastases to the pancreas were retrospectively reviewed. The primary tumors most commonly responsible for these metastases were renal cell carcinoma (30.3%) and bronchogenic carcinoma (22.7%). Metastases showed no predilection for any particular part of the pancreas. The majority (75.8%) of metastases appeared as tumors with discrete margins, and most of these tumors were round or ovoid with smooth borders. Over three-fourths of the lesions demonstrated enhancement (usually heterogeneous). Vascular involvement was uncommon. In those patients in whom pancreatic metastases were discovered some time after the primary tumor was identified, the interval ranged from 2 to 295 months, with the longest mean interval (120.2 months) being associated with metastatic tumors from renal cell carcinoma. The appearance of these tumors at CT--predominantly hyperattenuating masses, often with nonenhancing internal components--was similar to that of primary renal cell carcinoma. In most pancreatic metastases, however, clinical information in conjunction with CT characteristics such as multiplicity of tumors or hypervascularity permit differentiation of metastases from primary neoplasm. When diagnosis of a pancreatic neoplasm is uncertain, percutaneous biopsy often permits histologic confirmation of the tumor type.

Adolescent↗
PubMedDate not supplied

CT and MR imaging of primary cardiac malignancies.

Primary cardiac malignancies are rare tumors that are difficult to diagnose clinically. Different primary cardiac malignancies may have different clinical, morphologic, and radiologic features and intracardiac locations. Angiosarcoma is the most common primary cardiac malignancy. It tends to occur in the right atrium and involve the pericardium. Because of its tendency to hemorrhage, angiosarcoma often demonstrates areas of increased signal intensity with T1-weighted sequences. Undifferentiated sarcomas typically occur in the left atrium and have variable epidemiologic and radiologic features. Rhabdomyosarcoma is the most common primary cardiac malignancy in children and is more likely than other primary cardiac sarcomas to involve the valves. Primary cardiac osteogenic sarcoma almost always occurs in the left atrium and frequently demonstrates calcification. Certain features (eg, broad base of attachment, origin at a site other than the atrial septum) help differentiate this tumor from left atrial myxoma. Leiomyosarcoma favors the left atrium and tends to invade the pulmonary veins and mitral valve. Fibrosarcoma also tends to occur in the left atrium and is often necrotic. Liposarcoma is very rare and usually manifests as a large, infiltrating mass. Foci of macroscopic fat are occasionally seen. Primary cardiac lymphoma occurs more commonly in immunocompromised patients, frequently involves the pericardium, and, unlike other primary cardiac malignancies, may respond to chemotherapy. The advent of cross-sectional imaging has allowed earlier detection of primary cardiac malignancies as well as more accurate diagnosis and characterization.

Calcinosis↗