Radiology

Tada, T; Minakuchi, K; Fujioka, T; Sakurai, M; Koda, M; Kawase, I; Nakajima, T; Nishioka, M; Tonai, T; Kozuka, T

doi: N/Apmid: 9609904

PURPOSE: To test the feasibility of a system for intermittent irradiation synchronized with respiratory motion in a clinical setting. MATERIALS AND METHODS: A newly developed gate pulse controller that starts and stops irradiation at a chosen phase of the respiratory cycle by controlling a linear accelerator was used in six patients with lung cancer. A laser displacement sensor was used for the detection of respiratory motion. Three patients underwent radiation therapy during the cycles between 50% expiration and 50% inspiration (step 1), and three patients underwent radiation therapy during the cycles between 70% expiration and 30% inspiration (step 2). RESULTS: The system functioned well; irradiation was verified with portal verification radiography in all six patients. The range of the tumor position during synchronized irradiation was detectable with fast portal localization radiography. The treatment times for steps 1 and 2 were 1.38-1.71 and 2.03-2.18 times longer, respectively, than those for conventional irradiation. CONCLUSION: Synchronized irradiation with the authors' system allowed convenient and reliable reduction of the target volume. Further study is needed to standardize the system for clinical use.

Barentsz, J O; Berger-Hartog, O; Witjes, J A; Hulsbergen-van der Kaa, C; Oosterhof, G O; VanderLaak, J A; Kondacki, H; Ruijs, S H

doi: N/Apmid: 9609906

PURPOSE: To evaluate if the failure of chemotherapy in patients with advanced urinary bladder cancer can be predicted early in the course of chemotherapy with fast dynamic contrast material-enhanced magnetic resonance (MR) imaging. MATERIALS AND METHODS: In this prospective study, 22 consecutive patients with histologically proved advanced urinary bladder cancer underwent MR imaging before and after two, four, and six cycles of chemotherapy with methotrexate, vinblastine, adriamycin, and cisplatin (MVAC). The response after two chemotherapy cycles was evaluated by using conventional tumor size parameters at unenhanced MR imaging and with changes in the time to the start of tumor or lymph node enhancement at fast dynamic contrast-enhanced MR imaging. The results obtained with these techniques were compared with the findings at histopathology in cystectomy (n = 9) or multiple transurethral resection (n = 13) specimens obtained after completion of chemotherapy. RESULTS: After two MVAC cycles, the accuracy, sensitivity, and specificity in distinguishing responders from nonresponders with conventional MR imaging were 73%, 79%, and 63%, respectively. With the dynamic technique, these were 95%, 93%, and 100%, respectively. Although the differences between these values are not significant (P = .48 for sensitivity, .25 for specificity, and .07 for accuracy), the data indicate that dynamic enhanced MR imaging performed better than unenhanced MR imaging. Dynamic imaging yielded correct results after two MVAC cycles in 21 cases, and in all cases after four cycles. After four MVAC cycles, the accuracy of dynamic MR imaging was significantly better (P < .05). Persisting early enhancement after four MVAC cycles correctly corresponded with lack of response in all nine cases, and after two cycles in eight of these cases. The unenhanced MR technique showed initial tumor size reduction in three of these cases. CONCLUSION: Conventional and dynamic enhanced MR imaging were used to evaluate chemotherapy after two, four, and six cycles of MVAC in 22 patients with bladder cancer. After two cycles, dynamic MR imaging helped detect 13 of 14 responders and eight of eight nonresponders. It helped detect five of seven lymph node responders and two of two nonresponders. Thus, it may be possible to predict after two MVAC cycles whether a patient will respond to chemotherapy.

Coche, E E; Müller, N L; Kim, K I; Wiggs, B R; Mayo, J R

doi: N/Apmid: 9609900

PURPOSE: To determine the value of parenchymal findings at contrast material-enhanced spiral computed tomography (CT) in patients suspected to have pulmonary embolism (PE). MATERIALS AND METHODS: Eighty-eight patients suspected to have PE underwent contrast-enhanced spiral CT and ventilation-perfusion scintigraphy. Concordance between CT and scintigraphic results was used to diagnose or exclude PE. Pulmonary angiography was attempted in all patients with discordant CT and scintigraphic results or indeterminate scans. Parenchymal CT scans were assessed by two radiologists who were not aware of the diagnosis and who had access only to lung window images. RESULTS: Twenty-six patients had PE; 62 did not. Wedge-shaped pleural-based consolidation was seen in 16 patients with PE (62%) and 17 patients without PE (27%) (P < .05) (sensitivity, 62%; specificity, 73%). Linear bands were seen in 12 patients with PE (46%) and 13 patients without PE (21%) (P < .05) (sensitivity, 46%; specificity, 79%). There was no statistically significant difference in the frequency of non-wedge-shaped consolidation, areas of decreased attenuation, or atelectasis. Central and lower-lobe segmental pulmonary arteries that contained emboli were enlarged (P < .05). CONCLUSION: Parenchymal findings may suggest further investigations when results of spiral CT are inconclusive in diagnosis of PE.

Morrison, W B; Schweitzer, M E; Batte, W G; Radack, D P; Russel, K M

doi: N/Apmid: 9609883

PURPOSE: To determine the usefulness of primary and secondary magnetic resonance (MR) imaging signs of osteomyelitis. MATERIALS AND METHODS: MR imaging at 1.5 T was performed in 73 feet (62 patients) with clinical concern for osteomyelitis. Images were reviewed retrospectively and separately by two reviewers in a blinded fashion for primary (abnormal marrow signal intensity) and secondary (ulcer, cellulitis, soft-tissue mass, abscess, sinus tract, cortical interruption) signs associated with osteomyelitis. RESULTS: Of the 73 feet, 43 had osteomyelitis. Discordant marrow signal intensity between individual MR sequences was observed by reader 1 in six (8%) feet and by reader 2 in 15 (21%) feet. For primary signs, fast spin-echo short inversion time inversion-recovery and gadolinium-enhanced fat-suppressed T1-weighted images had the highest sensitivity, and T1-weighted and gadolinium-enhanced fat-suppressed T1-weighted images had the highest specificity and least interobserver variability. Signs of cutaneous ulcer, sinus tract, and cortical interruption had the highest positive predictive value for osteomyelitis; signs of soft-tissue mass and cortical interruption had the highest negative predictive value. All had good interobserver agreement except cellulitis. CONCLUSION: When osteomyelitis of the foot is suspected, marrow signal intensity can differ on different types of MR images. Identification of secondary signs may augment diagnostic confidence when abnormal marrow signal intensity is seen.

Burrows, P E; Robertson, R L; Mulliken, J B; Beardsley, D S; Chaloupka, J C; Ezekowitz, R A; Scott, R M

doi: N/Apmid: 9609880

PURPOSE: To determine the association of cerebral arterial anomalies and progressive cerebral arterial occlusive disease in infants with facial hemangiomas. MATERIALS AND METHODS: The cases of eight infants (seven girls and one boy) with the diagnosis of cervicofacial hemangioma and intracranial arterial anomalies were reviewed retrospectively. Findings from clinical and imaging examinations--including cranial computed tomography, magnetic resonance imaging and angiography, and catheter angiography--were evaluated. Serial imaging findings were studied to document progressive intracranial vascular changes. RESULTS: Five patients had additional associated congenital anomalies. Seven were treated with corticosteroids, interferon alfa-2a, or both. Progressive cerebrovascular occlusive changes were documented in four of the seven patients with serial imaging findings. Four other patients (all treated pharmacologically) had MR imaging documentation of cerebral infarction, and all had consistent, acquired neurologic symptoms. CONCLUSION: Intracranial arterial anomalies can coexist with cervicofacial hemangioma. Aneurysmal and occlusive changes are potentially progressive and can result in cerebral infarction. A causative association between occlusive cerebrovascular disease and pharmacologic treatment has not been excluded.

Yasuda, S; Shohtsu, A; Ide, M; Takagi, S; Takahashi, W; Suzuki, Y; Horiuchi, M

doi: N/Apmid: 9609903

PURPOSE: To determine the frequency and clinical importance of diffuse 2-fluorine-18fluoro-2-deoxy-D-glucose (FDG) uptake in the thyroid gland. MATERIALS AND METHODS: A total of 1,102 healthy subjects underwent whole-body positron emission tomography (PET). PET images were evaluated for increased diffuse FDG uptake in the thyroid gland. Serum free thyroxine and thyrotropin levels were measured in 36 subjects with increased uptake and in 36 matched control subjects without uptake. Antithyroid antibodies were also measured. Morphologic abnormalities were examined by using ultrasonography (US). RESULTS: Diffuse FDG uptake was found in three men and 33 women; the prevalence was significantly higher in women (P < .01). Thirty-five subjects were euthyroid; one had hypothyroidism. Antithyroid antibodies were positive in 27 subjects. In most subjects, US findings facilitated the diagnosis of chronic thyroiditis. In control subjects, the positive rates for antithyroid antibodies and US abnormalities were significantly lower than those of the study group (P < .01). CONCLUSION: Diffuse thyroidal FDG uptake may be an indicator of chronic thyroiditis. The actual prevalence of the disorder was not low in this series, and such lesions may be found incidentally at FDG PET.

Giess, C S; Keating, D M; Osborne, M P; Ng, Y Y; Rosenblatt, R

doi: N/Apmid: 9609889

PURPOSE: To evaluate the clinical, imaging, and histopathologic features of breast carcinoma in the retroareolar tissues and to determine whether there are any characteristics common to this location. MATERIALS AND METHODS: Thirty-five patients (age range, 38-77 years) with 37 retroareolar carcinomas were identified retrospectively. Retroareolar carcinoma was defined as that within 2 cm of the nipple-areolar complex. Mammographically occult tumors were identified by using histopathologic records (n = 4) or clinical examination findings (n = 6). RESULTS: Twenty-nine (78%) tumors had clinical findings, including palpable mass (n = 29), associated nipple inversion or retraction (n = 4), and associated nipple discharge (n = 2). Twenty-seven (73%) tumors had mammographic findings of mass (n = 16), mass with calcifications (n = 5), and microcalcifications (n = 6; four of these microcalcifications were associated with a mammographically occult palpable mass). Ultrasound was performed in 17 tumors, all of which were hypoechoic. The stage of 31 carcinomas was known: one was stage 0, 17 were stage I, and 13 were stage II. Histopathologic analysis revealed 35 ductal carcinomas and two invasive lobular carcinomas. CONCLUSION: Retroareolar carcinoma usually manifests as a palpable mass. Mammography is less sensitive in this area than in other areas of the breast. Ultrasound can be a valuable adjunct in the assessment of retroareolar malignancy.

Melhem, E R; Caruthers, S D; Jara, H

doi: N/Apmid: 9609910

In 11 volunteers, magnetic resonance (MR) imaging of the cervical spine was performed with a magnetization transfer preparatory pulse (prepulsed), three-dimensional Fourier transform, turbo field echo sequence. The effects of flip angle, number of shots, phase-encoding profile order, and magnetization transfer prepulse offset frequency on cerebrospinal fluid-to-cord contrast were evaluated. The contrast was improved by lowering the flip angle, increasing the number of shots, and implementing a magnetization transfer prepulse and linear phase-encoding profile order. Maximum myelographic effect was achieved with the magnetization prepulse (500-Hz frequency offset), 3 degrees flip angle, six shots, and linear phase-encoding profile order.

Yoon, K H; Ha, H K; Kim, M H; Seo, D W; Kim, C G; Bang, S W; Jeong, Y K; Kim, P N; Lee, M G; Auh, Y H

doi: N/Apmid: 9609898

PURPOSE: To evaluate the clinical and radiologic features of biliary stricture after blunt abdominal trauma and to report the results of endoscopic stent placement. MATERIALS AND METHODS: Medical records and radiologic findings were reviewed in five patients with biliary stricture after blunt abdominal trauma. The level, length, and contour of the strictures were analyzed with endoscopic retrograde cholangiopancreatography (ERCP). Computed tomographic (CT) scans were also reviewed to determine the presence of biliary dilatation, configuration of the injured bile duct, and ancillary abdominal findings. Results from endoscopic stent placement were evaluated in all patients. RESULTS: Stricture occurred in the suprapancreatic portion of the common bile duct in four patients and in the intrapancreatic portion in one patient. At ERCP, the stricture contour was concentric and smooth in three patients, eccentric and smooth in one, and abruptly terminated in one. CT showed abrupt narrowing of the common bile duct with dilatation of the proximal portion in all patients. Endoscopic stent placement was successful in all patients. CONCLUSION: Patients with biliary stricture after blunt abdominal trauma exhibit a delayed onset of symptoms. A correct diagnosis may be difficult on the basis of findings from CT or ERCP alone without a clinical history or evidence of contusions at other sites.

Bellin, M F; Roy, C; Kinkel, K; Thoumas, D; Zaim, S; Vanel, D; Tuchmann, C; Richard, F; Jacqmin, D; Delcourt, A; Challier, E; Lebret, T; Cluzel, P

doi: N/Apmid: