Asunto(s)

RESUMEN

PURPOSE: To determine the accuracy of a probably benign assessment of non-palpable breast lesions (BI-RADS category 3) at mammography and/or ultrasound with immediate histological work-up. MATERIALS AND METHODS: Stereotactic or ultrasound guided core needle breast biopsy (NBB) was performed to evaluate 288 lesions, which were prospectively assessed as BI-RADS category 3. Imaging findings included 195 masses, 73 calcification cases, 16 focal asymmetries, and four architectural distortion cases. After NBB, patients underwent either open surgical biopsy (OSB) (n=204) or mammographic follow-up (n=84) for at least 24 months. Histological results of NBB were compared with those of OSB. RESULTS: Three of the 288 lesions (1.0%) proved to be malignant at histological work-up, two of them were ductal carcinoma in situ (DCIS) and one of them was an invasive carcinoma. NBB revealed invasive carcinoma in 1/288 (0.35%) and atypical ductal hyperplasia (ADH) in 13/288 (4.5%) lesions. OSB revealed DCIS in 2/204 (1%) and invasive carcinoma in 1/204 (0.5%) lesions. The two DCIS were underestimated as ADH by NBB. The remaining 285 (99%) lesions proved to be benign at OSB or remained stable during follow-up. CONCLUSION: Confirmed by tissue diagnosis, the low likelihood of malignancy of prospectively assessed probably benign lesions is below the 2% threshold established for BI-RADS category 3. Imaging follow-up is a safe and effective alternative to immediate histological work-up for such lesions.

Asunto(s)

RESUMEN

PURPOSE: To analyze data at the time of diagnosis of breast cancer in three radiology practices in Austria in the setting of opportunistic screening. MATERIALS AND METHODS: In 529 women (ages 31 - 89, mean age 61.1) with breast cancer, the mode of diagnosis (detected clinically or by opportunistic screening), the local tumor stages, and intervals between screening examinations were assessed. RESULTS: In 33.6 % (178 of 529) of the cases, the breast cancer was detected clinically, and in 66.4 % (351 of 529) of the cases, the cancer was detected by opportunistic screening. Cancers in prognostically favorable stages (in situ carcinomas, pT1 a, pT1 b, pT1c) were detected by opportunistic screening in 79.9 % of the cases. The clinically detected cancers were in locally advanced stages (pT2, pT3) in 58.4 % of the cases. In the majority of clinically detected cases (75 %), the women had never had a mammogram before or had not had a recent one. In 13 % of the cases detected by opportunistic screening, diagnosis was made during the first exam, in 40 % of the cases, the period since the last mammogram was less than 24 months, and in 47 % of the cases, this period was greater than 24 months. CONCLUSION: In our patients the majority of breast cancers were detected in early stages by opportunistic screening. The use of an organized system with exams at regular intervals may further reduce the number of advanced cancers.

Asunto(s)

RESUMEN

PURPOSE: To determine whether palpable non-calcified solid breast masses with benign morphology on ultrasound can be classified as probably benign and whether these lesions fulfill the criteria required for BI-RADS (TM) category III. MATERIALS AND METHODS: This analysis includes 78 patients with 80 palpable non-calcified solid masses that were classified as probably benign at initial sonography. Of 78 patients, 66 had periodic imaging surveillance (2 - 8 years, mean 4.6 years). The remaining 12 patients had a biopsy after initial imaging. RESULTS: In the 64 patients under surveillance, palpable lesions remained stable at follow-up. In 2 patients lesions increased in size during follow-up and no malignancy was diagnosed at subsequent open biopsy. In 19 of the 66 patients, 29 additional nonpalpable lesions of similar morphology were detected on ultrasound. No malignancy was diagnosed in the 12 patients, who had a biopsy after initial imaging. CONCLUSION: Our data suggest that palpable non-calcified solid breast masses with benign morphology on ultrasound can be classified as probably benign (BI-RADS (TM) category III). Biopsy can be averted when lesions remain stable at follow-up.

Asunto(s)

RESUMEN

The purpose of this study was to evaluate the diagnostic efficacy of the double inversion recovery fast spin echo (DIR-FSE) sequence for brain imaging compared to the fluid-attenuated inversion recovery (FLAIR) sequence. DIR-FSE and FLAIR-FSE sequences were obtained and compared side by side. Image assessment criteria included lesion conspicuity, contrast between different types of normal tissue, image quality, and artifacts. In addition, contrast ratios and contrast-to-noise ratios were determined. Scan time of DIR-FSE was 33% longer than scan time of FLAIR-FSE. Overall lesion conspicuity was equal on DIR-FSE and FLAIR-FSE; however, DIR-FSE showed particular advantages for infratentorial lesions and lesions with only poor contrast on T2-weighted images, whereas FLAIR was slightly superior for small superficial cerebral abnormalities. Gray-white differentiation was better with DIR-FSE. Cerebrospinal fluid suppression was equal on both sequences; cerebrospinal fluid pulsation artifacts were more pronounced on DIR-FSE but did not cause diagnostic difficulties on these images. We conclude that DIR-FSE might be obtained if infratentorial lesions and abnormalities with only slightly prolonged T2 relaxation times are suspected. Otherwise, FLAIR-FSE seems preferable.

Asunto(s)

RESUMEN

OBJECTIVE: The purpose of this study was to determine the conspicuity of pancreatic adenocarcinoma and surrounding critical pancreatic vascular structures on helical CT scans obtained during the arterial and portal venous phases of enhancement. SUBJECTS AND METHODS: Forty patients with pancreatic adenocarcinomas under-went dual-phase helical CT (3-mm collimation; l-mm overlapping reconstructions; 160 ml contrast medium injected at 4 ml/sec; scan delay: 18 sec for arterial phase, 60 sec for portal venous phase). Tissue enhancement and differences in tumor-to-pancreas contrast were compared. Quantitative evaluation was also done for the aorta, the superior mesenteric artery and vein, and the splenic and portal veins. RESULTS: Tumor conspicuity was significantly greater in the portal venous phase, when the tumor-to-pancreas contrast difference was 54 +/- 31 H, than in the arterial phase, when the difference was 31 +/- 29 H. Enhancement values of critical pancreatic venous structures were significantly greater in the portal venous phase than in the arterial phase. CONCLUSION: Arterial-phase helical CT in patients with pancreatic adenocarcinoma is of limited benefit: lesion conspicuity is suboptimal and depiction of venous anatomy is inferior to the depiction possible with venous-phase helical CT.

Asunto(s)

RESUMEN

OBJECTIVE: The purpose of this study was to describe the variable anatomy of mesenteric veins on axial CT images and on volume-rendered CT venograms that use maximum intensity projection and shaded-surface display. SUBJECTS AND METHODS: Fifty-seven patients undergoing helical CT of the pancreas were included in the study. The mesenteric venous system was analyzed in 54 patients. Three patients were excluded because the helical CT data were unsatisfactory. RESULTS: On helical CT with maximum intensity projection and shaded-surface display, the superior mesenteric vein (SMV) was seen as a single trunk of variable length in 40 patients. In seven other patients, two mesenteric trunks merged separately with the splenic vein. In the remaining seven patients, the SMV was occluded by tumor. The inferior mesenteric vein drained into the splenic vein in 28 patients (56%), into the SMV in 14 patients (26%), and into the splenomesenteric angle in nine patients (18%). CONCLUSION: Both axial and volume-rendered CT venograms accurately reveal the variable mesenteric venous anatomy. CT venograms may replace conventional angiography in presurgical planning.

Asunto(s)

RESUMEN

OBJECTIVE: The purpose of this study was to determine hepatic, aortic, and portal vein enhancement with a new dimeric, nonionic, isotonic contrast medium (iodixanol) in a routinely performed helical CT protocol and compare enhancement characteristics with those of a monomeric, nonionic, low-osmolality contrast medium (iopromide). SUBJECTS AND METHODS: In 81 patients, we injected 150 ml of iodixanol (320 mg I/ml), iodixanol (300 mg I/ml), or iopromide (300 mg I/ml). Injection rate was 5 ml/sec. A dual-phase helical CT scan was obtained (first helical scan began at 30 sec. second helical scan began at 70 sec), and enhancement characteristics were assessed. Results were analyzed taking into account various intrinsic parameters of patients. RESULTS: During the second imaging phase, iodixanol at 320 mg I/ml and iodixanol at 300 mg I/ml provided significantly higher enhancement of the liver (75 H, 69 H, 62 H), aorta (144 H, 140 H, 122 H), and portal vein (147 H, 147 H, 118 H) than did iopromide at 300 mg I/ml. No significant differences were observed during the first imaging phase. CONCLUSION: The combination of higher vascular and parenchymal enhancement levels after injection of the isotonic agent may represent a different quality of tissue enhancement. Such an enhancement would be characterized more by a higher contribution of the blood pool compartment to absolute enhancement levels than by a contribution of the interstitial compartment. Further studies are needed to determine whether the use of isotonic agents effects lesion conspicuity.

Asunto(s)

RESUMEN

PURPOSE: We report our preliminary results with a new type of self-expanding covered stent for treatment of malignant biliary obstruction. METHODS: Wallstents, fully covered with high elasticity polyurethane, with an unconstrained diameter of 10 mm and a total length of 69 mm, were placed transhepatically under fluoroscopic guidance in five patients. The length of the biliary obstruction varied between 30-50 mm. At 1 and 3 months (82-98 days) clinical assessment, serum bilirubin measurement, and ultrasound examination of the biliary tree were performed. RESULTS: Initial uncomplicated deployment of the stents and internal drainage was possible in all patients. Distal stent migration resulted in early biliary reobstruction in one patient. At 3-month follow-up, partial reobstruction, most probably due to sludge formation, was found in another patient. CONCLUSION: Our initial results indicate that the covered, self-expanding Wallstent endoprosthesis can be reliably and safely deployed transhepatically for malignant biliary obstruction.

Asunto(s)

RESUMEN

PURPOSE: To evaluate permanent hepatic artery embolization of liver metastases of malignant insulinoma as a therapeutic procedure. METHODS: Three female patients had persistent severe hypoglycemia after distal pancreatectomy because of a malignant insulinoma. Computed tomography (CT) and CT-portography (CTAP) were used for tumor assessment and follow-up and demonstrated multiple hypervascular metastases 0.5-3 cm in diameter in both lobes of the liver. Unilobar sequential transcatheter embolization of the hepatic artery was performed with an interval of 1-2 months between the procedures. Permanent occlusion was achieved by using a mixture of n-butyl-2-cyanoacrylate and ethiodized oil as an embolizing agent. RESULTS: In all patients, embolization of the hepatic artery was technically feasible and complete occlusion could be obtained. In two patients, collaterals originating from the right inferior phrenic artery were embolized superselectively 3 months after bilobar embolization. CTAP at that time revealed marked decrease in tumor size of more than 50%. All patients responded to the treatment as confirmed by normalization of measurable hormone levels, glucose levels, and disappearance of symptoms. Two patients are still alive after 24 and 31 months from the time of the first embolization. Current investigations revealed normal laboratory data and no further tumor progression in the liver. The third patient died 15 months after the first embolization; she also had developed ileus due to local recurrence of the primary tumor and lymph node metastases. CONCLUSION: Hepatic arterial embolization appears to be an effective means of palliation for liver metastases of malignant insulinoma. Long-term improvement seems most likely to be the result of extensive ischemia from permanent occlusion.

Asunto(s)

RESUMEN

PURPOSE: To determine the optimal time window for scanning the liver with computed tomography (CT) during arterial portography (CTAP). MATERIALS AND METHODS: After vasodilation and contrast medium injection into the superior mesenteric artery (80 mL at 5 mL/sec), 25 repeated scans were obtained at a single level within 83 seconds in 13 patients. Attenuation was measured on every scan, and time-attenuation curves were created. Enhancement characteristics of the portal vein, liver parenchyma, aorta, and tumors were evaluated. RESULTS: Parenchymal enhancement of more than 60 HU was achieved between 18 seconds +/- 4 (standard deviation) and 67 seconds +/- 15, and high parenchyma-to-tumor contrast of more than 50 HU occurred between 18 seconds +/- 3 and 62 seconds +/- 14. CONCLUSION: To scan the liver within such a narrow time window, a spiral CT technique is necessary. When the above injection parameters are used in CTAP, the spiral CT sequence should be started 20 seconds after the beginning of the injection.

Asunto(s)

RESUMEN

Benign stenoses of the oesophagus have been conventionally treated by endoscopic bougienage and were operated on in case of failure. Now that balloon catheters with large balloon diameters are available, interventional radiological dilatation of enteric strictures can be easily performed. In case of eccentric high-grade stenosis with or without blind loop, stenosis is often easier to manage and associated with less risk with an angiographic guide wire and catheter than by endoscopy. 53.3% of the patients were referred to balloon dilatation after failed endoscopic bougienage. The indications for balloon dilatation were anastomotic stenosis (66.2%), peptic stenosis (16.9%), achalasia (7%), pylorospasm (5.6%) and stenosis due to pemphigus vulgaris, acid ingestion and (in one case) a Schatzki ring. The complication rate was low at 1%. The experience collected with 297 dilatations in 71 patients with benign oesophageal stenosis, is reported.

Asunto(s)

RESUMEN

60 patients with carcinoma of the gallbladder were staged preoperatively by sonography (staging scheme by Nevin and TNM scheme of the UICC). This was correlated with the operative and histopathological findings. The tumour was diagnosed by sonography in 70% of the patients, 15% were diagnosed at operation and 15% histopathologically. The criterion for malignancy was tumour invasion into the liver (94.7% Sensitivity) and/or into adjacent tissues (36.8% Sensitivity). Most tumours were in an advanced stage (98.5%) and only one early carcinoma (1.5%) was found histopathologically. No improvement in the diagnosis of early carcinomas was achieved by ultrasound in our series.

Asunto(s)