Biomedical subjects

R E Bechtold

Publications and source records attributed to R E Bechtold.

27 records · Page 2Linked to original sources

PubMedDate not supplied

Cystic changes in hepatic and peritoneal metastases from gastrointestinal stromal tumors treated with Gleevec.

BACKGROUND: Tyrosine kinase inhibitor (Gleevec or STI-571) must be considered the treatment of choice for metastatic gastrointestinal stromal tumors (GISTs). The purpose of this article is to address and illustrate a long-term follow-up of computed tomographic (CT) radiologic findings in patients with metastases from GIST after Gleevec treatment. METHODS: We performed a retrospective review of seven patients (four male, three female) with unresectable metastases from GIST who were treated with STI-571 in a 1-year period. Patients were followed every 2-4 months by contrast-enhanced CT for up to 12 months. The size and attenuation of hepatic and peritoneal metastases on CT were measured and correlated. RESULTS: Hepatic metastases from GISTs showed significant decreased attenuation from a mean of 60 HU to a mean of 32 HU (p < 0.01) in the first 2 months and continued decreasing attenuation to 23 HU at the 12-month follow-up. These metastases superficially resembled simple cysts. Most metastases became smaller, with more defined borders, after treatment. Histologic examination in a resected specimen revealed hepatic cyst with no residual tumor cells, regression of omental lesions, and extensive necrosis. CONCLUSIONS: CT findings of unresectable hepatic and peritoneal metastases from GIST displayed decreasing, near cystic attenuation and size as an effective regression in response to STI-571 treatment.

Adult↗

PubMedDate not supplied

CT appearance of disseminated peritoneal adenomucinosis.

Disseminated peritoneal adenomucinosis (DPAM) is a relatively rare cause of pseudomyxoma peritonei, marked by peritoneal lesions with abundant extracellular mucin and little cytologic atypia among exfoliated tumor cells, and usually associated with appendiceal adenomas. Peritoneal mucinous carcinomatosis (PMCA) also causes diffuse peritoneal tumor but is marked by neoplastic mucinous epithelium with cytologic features of carcinoma and associated with appendiceal, colon, gastric, or small bowel carcinoma. Compared with PMCA, DPAM has a different distribution of disease and a significantly better prognosis. DPAM is characterized by the lack of lymph node involvement, with primarily superficial peritoneal involvement, and a relatively benign, relapsing course over many years. Dominant primary masses may not be evident in DPAM. Despite considerable overlap in the two main causes of pseudomyxoma peritonei, there are features of the two that may help differentiate between them. We present the computed tomographic appearance of DPAM in a series of seven cases and emphasize characteristics of the disease.

Adenoma↗

PubMedDate not supplied

Prolonged hepatic enhancement on computed tomography in a case of hepatic lymphoma.

Hepatic lymphoma is often very difficult to detect using any modality. A case of hepatic lymphoma appeared on rapid contrast infused CT as extremely prolonged and bizarre enhancement. The specific features included a widespread and aggressive appearance with a variable pattern of contrast enhancement. There was one localized area of apparent centripetal accumulation of contrast medium. The prolonged and irregular enhancement may be due to contrast medium "trapping" in interstitial spaces or even to the fact that a bolus technique was used.

Aged↗

PubMedDate not supplied

MR imaging of anterior cruciate ligament repair.

Magnetic resonance (MR) imaging is an accurate means of analyzing disruptions of the native anterior cruciate ligament (ACL). Various techniques may be used to repair a disrupted ACL. A common repair is the MacIntosh lateral-substitution over-the-top repair in which a strip of fascia lata from the iliotibial band is used as a "neoligament." The results of 27 MR examinations of 17 athletes with this repair were analyzed to determine the appearance of the neoligament on MR. Thirteen of the 17 patients had returned to full athletic activity and four were capable of strenuous activity. Examinations were made at both 0.5 and 1.5 T in varied extents of external rotation from 0 to 20 degrees, and at variable time intervals after surgery from 1 to nearly 40 months. Only two patients clinically required postrepair arthroscopy, but both had normal repairs. Neoligaments were classified as well-defined (n = 6 studies), ill-defined (n = 10), and not discernible (n = 11), based on clarity of appearance. Reasons for this variable appearance include the variable presence of fibrous and fatty tissue investing the neoligament. We conclude that the normal neoligament, unlike the normal active ACL, has a variable appearance, including nonvisualization on MR and that criteria used in evaluating the native ligament will be inadequate to assess the repair.

Adolescent↗

PubMedDate not supplied

MR appearance of sternal hyperostosis.

Sternal hyperostosis is characterized by prominent new bone formation and fibrosis with less pronounced areas of granulation tissue and round cell infiltration. In previously reported cases the process involved not only the sternum but adjacent bony areas as well. Depending upon the extent of disease, acquiring biopsy material for histologic analysis can be difficult. We report a case of sternal hyperostosis involving the sternum exclusively and extensively. Magnetic resonance imaging was useful in directing biopsy for optimal histologic yield. This unusual case of sternal hyperostosis is believed to be the result of an inflammatory process.

Adult↗

PubMedDate not supplied

Occult pneumothorax in patients with abdominal trauma: CT studies.

Abdominal CT, which routinely includes the lower thorax, is an important adjunct to supine chest radiography in detecting chest injury in patients with blunt abdominal trauma. In 1,086 consecutive patients with blunt abdominal trauma, 223 of whom had both supine chest radiography and abdominal CT, 49 patients examined with both techniques had pneumothoraces, 28 of them occult (seen only on CT). To help guide management, we established three categories of occult pneumothorax, based on size and location: (a) minuscule (< 1 cm in greatest thickness, seen on four or fewer images); (b) anterior (> 1 cm in greatest thickness, but not extending beyond the midcoronal line); (c) anterolateral (extending beyond the midcoronal line). In our study four of six patients with minuscule pneumothorax, including one who required mechanical ventilation, were observed without complications; two of six patients had chest tube placement. Seven of 14 cases with anterior pneumothorax were observed and resolved without complication; seven had chest tube placement. All eight patients with anterolateral pneumothoraces underwent percutaneous tube thoracostomy, regardless of proposed management.

Abdominal Injuries↗

PubMedDate not supplied

Interpretation of abdominal CT: analysis of errors and their causes.

PURPOSE: Our goal was to analyze those factors contributing to the error rate in the interpretation of abdominal CT scans at an academic medical center. METHOD: From a total of 694 consecutive patients (329 male, 365 female), we evaluated the error rates of interpreting abdominal CT studies. The average patient age was 54 years. All abdominal CT studies were reviewed by three to five CT faculty radiologists on the morning after the studies were performed. The error rate was correlated with reader variability, the number of cases read per day, the presence of a resident, inpatient versus outpatient, organ systems, etc. The chi 2-test was used for statistical analysis. RESULTS: A total of 56 errors were found in the reports of 53 patients (overall error rate = 7.6%). Of these errors, 19 were judged to be clinically significant and 7 affected patient management. A statistically significant difference in error rates was noted among the five faculty radiologists (3.6-16.1%, p = 0.00062). No significant correlates between error rates and any of the other variables could be established. CONCLUSION: The primary determinant of error rates in body CT is the skill of the interpreting radiologist.

Abdomen↗

PubMedDate not supplied

Magnetic resonance imaging of pediatric hip disease.

The efficacy of magnetic resonance imaging (MRI) in the assessment of pediatric hip disease was tested by scanning the hips of 24 children (30 scans). Twelve patients with Legg-Calvé-Perthes disease (17 hips) showed characteristic areas of low-intensity signal representative of necrotic areas of the capital epiphysis. Abnormal scans were also obtained on patients with transient synovitis, avascular necrosis secondary to steroids, epiphyseal dysplasia, and multiple osteochondromatosis. MRI accurately shows articular cartilage, femoral head shape, quality of containment, and areas of necrosis in pediatric hips. The extent of involvement and revascularization can be identified in Legg-Calvé-Perthes disease.

Adolescent↗

PubMedDate not supplied

Postoperative computed tomographic evaluation of congenital hip dislocation.

The use of computed tomography (CT) in the postoperative evaluation of 19 congenitally dislocated hips is presented so that appropriate indications for reduction can be determined and radiologic criteria can be defined for judging whether reduction is satisfactory. The radiologic technique is presented. CT is an accurate and cost-effective modality that is capable of demonstrating subtle changes in femoral head position.

Female↗