Radiologia Brasileira最新文献

Acute calcific periarthritis (ACP) is defined as periarticular inflammation associated with intra-articular deposits of hydroxyapatite and other basic calcium phosphate crystals. Patients with ACP present with a sudden onset of pain, together with localized swelling, as well as erythema, tenderness, and reduced range of motion. Familiarity with the clinical and radiological manifestations of ACP aids in the diagnosis and helps differentiate it from other conditions, particularly infectious or inflammatory pathologies such as septic arthritis and gout, thereby reducing the number of unnecessary diagnostic and therapeutic procedures. The objective of this pictorial essay is to illustrate the imaging findings of ACP in various joints, with an emphasis on the findings obtained by magnetic resonance imaging.

Objective: To evaluate the diagnostic accuracy of multi-echo Dixon magnetic resonance imaging (MRI) in hepatic fat quantification, in comparison with that of magnetic resonance spectroscopy (MRS), on 3.0-T MRI.

Materials and methods: Fifty-five adults with no known liver disease underwent MRI in a 3.0-T scanner for determination of the hepatic fat fraction, with two techniques: multi-echo Dixon, in a manually drawn region of interest (ROI) and in the entire liver parenchyma (automated segmentation); and MRS. The diagnostic accuracy and cutoff value for multi-echo Dixon were determined, with MRS being used as the reference standard.

Results: The mean fat fraction obtained by multi-echo Dixon in the manually drawn ROI and in the entire liver was 5.2 ± 5.8% and 6.6 ± 5.2%, respectively, whereas the mean hepatic fat fraction obtained by MRS was 5.7 ± 6.4%. A very strong positive correlation and good agreement were observed between MRS and multi-echo Dixon, for the ROI (r = 0.988, r² = 0.978, p < 0.001) and for the entire liver parenchyma (r = 0.960, r² = 0.922, p < 0.001). A moderate positive correlation was observed between the hepatic fat fraction and body mass index of the participants, regardless of the fat estimation technique employed.

Conclusion: For hepatic fat quantification, multi-echo Dixon MRI demonstrated a very strong positive correlation and good agreement with MRS (often considered the gold-standard noninvasive technique). Because multi-echo Dixon MRI is more readily available than is MRS, it can be used as a rapid tool for hepatic fat quantification, especially when the hepatic fat distribution is not homogeneous.

Objective: To evaluate the correlation between multidetector computed tomography (MDCT) findings and laboratory test results in patients with pulmonary tuberculosis (PTB).

Materials and methods: A total of 57 patients were evaluated. Patients with suspected PTB were divided into groups according to the final diagnosis (confirmed or excluded), and the groups were compared in terms of sociodemographic variables, clinical symptoms, tomography findings, and laboratory test results.

Results: Among the patients with a confirmed diagnosis of PTB, small pulmonary nodules with a peribronchovascular distribution were significantly more common in the patients with a positive sputum smear microscopy result (47.4% vs. 8.3%; p = 0.046), as were a miliary pattern (36.8% vs. 0.0%; p = 0.026), septal thickening (84.2% vs. 41.7%; p = 0.021), and lymph node enlargement (52.6% vs. 8.3%; p = 0.020). Small pulmonary nodules with a centrilobular distribution were significantly more common among the culture-positive patients (75.0% vs. 35.7%; p = 0.045), as was a tree-in-bud pattern (91.7% vs. 42.9%; p = 0.014). A tree-in-bud pattern, one of the main tomography findings characteristic of PTB, had a sensitivity, specificity, positive predictive value, and negative predictive value of 71.0%, 73.1%, 75.9%, and 67.9%, respectively.

Conclusion: MDCT presented reliable predictive values for the main tomography findings in the diagnosis of PTB, being a safe tool for the diagnosis of PTB in patients with clinical suspicion of the disease. It also appears to be a suitable tool for the selection of patients who are candidates for more complex, invasive examinations from among those with high clinical suspicion of PTB and a negative sputum smear microscopy result.

Objective: To compare conventional transarterial chemoembolization (cTACE) and drug-eluting bead TACE (DEB-TACE) in terms of efficacy, survival, and adverse effects in patients with hepatocellular carcinoma who are not candidates for curative therapy.

Materials and methods: This was a retrospective study of patients with hepatocellular carcinoma who underwent cTACE or DEB-TACE for palliative treatment between January 2009 and December 2021. The Kaplan-Meier method was used for survival analysis. Values of p < 0.05 were considered statistically significant.

Results: We evaluated 268 patients, of whom 70 underwent DEB-TACE and 198 underwent cTACE. There was no significant difference between the groups regarding sex, age, or etiology of cirrhosis. The proportion of patients achieving a complete response on imaging examinations was higher in the cTACE group (31.8% vs. 16.1%), whereas that of patients achieving a partial response was higher in the DEB-TACE group (33.9% vs.19.7%), and the differences were significant (p = 0.014). The mortality rate was similar between the groups. The survival rate in the DEB-TACE and cTACE groups, respectively, was 87.0% and 87.9% at one year, 35.1% and 32.9% at three years, and 20.5% and 18.1% at five years (p = 0.661). There was no significant difference between the DEB-TACE and cTACE groups in terms of the frequency of adverse events (7.1% vs. 17.8%; p = 0.052). The most common complication in both groups was post-embolization syndrome.

Conclusion: Although a complete response was more common among the patients who underwent cTACE, there was no difference in survival between the groups and the frequency of adverse events was similar.

Although kidney transplantation is the best therapeutic option for patients with chronic kidney disease, the immunosuppression required greatly increases susceptibility to infections that are responsible for high post-transplant mortality. Pulmonary tuberculosis (TB) represents a major cause of such infections, and its early diagnosis is therefore quite important. In view of that, we researched the manifestations of active pulmonary TB in kidney transplant recipients, through chest X-ray and computed tomography (CT), as well as determining the number of cases of active pulmonary TB occurring over a 3.5-year period at our institution. We identified four cases of active pulmonary TB in kidney transplant recipients. The CT scans provided information complementary to the chest X-ray findings in all four of those cases. We compared our CT findings with those reported in the literature. We analyzed our experience in conjunction with an extensive review of the literature that was nevertheless limited because few studies have been carried out in lowand middle-income countries, where the incidence of TB is higher.

Objective: To determine the branching patterns of the inferior mesenteric artery (IMA) and to describe the clinical applicability of computed tomography (CT) angiography in the evaluation of these vessels to facilitate the planning of colorectal cancer surgery.

Materials and methods: We included 100 patients who underwent CT angiography of the abdomen and pelvis. The branching patterns of the IMA were examined and classified as type 1 (bifurcated), including 1A (sigmoid and left colic arteries arising from a common trunk), 1B (sigmoid and superior rectal arteries arising from a common trunk) and 1C (sigmoid arteries arising from both trunks); type 2 (trifurcated); and type 3 (no left colic branch).

Results: Among the 100 patients evaluated, we found the variant to be type 1A in 9%, type 1B in 47%, type 1C in 24%, type 2 in 16%, and type 3 in 4%.

Conclusion: Preoperative CT angiography for evaluating the IMA branching pattern could inform decisions regarding the surgical approach to colorectal cancer.

Objective: To study the effect of antenatal corticosteroid administration on fetal hemodynamics using longitudinal analysis of Doppler waveforms in the umbilical artery (UA) and middle cerebral artery (MCA).

Materials and methods: This was a retrospective study that included 30 fetuses at risk for preterm birth. Twenty-eight pregnant women were treated with betamethasone for fetal lung maturation. Doppler examinations of the UA and MCA were performed once before and three or eight times after corticosteroid administration. We used a Bayesian hierarchical linear model. Reference ranges were constructed, and associations between variables (gestational age and pre-eclampsia) were tested.

Results: The mean maternal age, gestational age at betamethasone administration, and gestational age at delivery were 32.6 ± 5.89 years, 30.2 ± 2.59 weeks, and 32.9 ± 3.42 weeks, respectively. On UA Doppler, there was a significant decrease in the pulsatility index (PI) after corticosteroid administration, with a mean of 0.1147 (credibility interval: 0.03687-0.191) in three observations and a median of 0.1437 (credibility interval: 0.02509-0.2627) in eight observations. However, there was no significant change in the Doppler MCA PI, regardless of gestational age and the presence or absence of pre-eclampsia.

Conclusion: Although antenatal corticosteroid administration induced a significant decrease in the Doppler UA PI, we observed no change in the cerebral vasculature.

Objective: To describe the accuracy of HealthVCF, a software product that uses artificial intelligence, in the detection of incidental moderate-to-severe vertebral compression fractures (VCFs) on chest and abdominal computed tomography scans.

Materials and methods: We included a consecutive sample of 899 chest and abdominal computed tomography scans of patients 51-99 years of age. Scans were retrospectively evaluated by the software and by two specialists in musculoskeletal imaging for the presence of VCFs with vertebral body height loss > 25%. We compared the software analysis with that of a general radiologist, using the evaluation of the two specialists as the reference.

Results: The software showed a diagnostic accuracy of 89.6% (95% CI: 87.4-91.5%) for moderate-to-severe VCFs, with a sensitivity of 73.8%, a specificity of 92.7%, and a negative predictive value of 94.8%. Among the 145 positive scans detected by the software, the general radiologist failed to report the fractures in 62 (42.8%), and the algorithm detected additional fractures in 38 of those scans.

Conclusion: The software has good accuracy for the detection of moderate-to-severe VCFs, with high specificity, and can increase the opportunistic detection rate of VCFs by radiologists who do not specialize in musculoskeletal imaging.

The majority of central nervous system diseases show high signal intensity on T2-weighted magnetic resonance imaging. Diseases of the central nervous system with low signal intensity are less common, which makes it a finding that helps narrow the differential diagnosis. This was a retrospective analysis of brain and spine magnetic resonance imaging examinations in which that finding was helpful in the diagnostic investigation. We selected the cases of patients examined between 2015 and 2022. All diagnoses were confirmed on the basis of the clinical-radiological correlation or the histopathological findings. We obtained images of 14 patients with the following central nervous system diseases: arteriovenous malformation; cavernous malformation; metastasis from lymphoma; medulloblastoma; embryonal tumor; metastasis from melanoma; Rathke's cleft cyst; Erdheim-Chester disease; aspergillosis; paracoccidioidomycosis; tuberculosis; syphilis; immunoglobulin G4-related disease; and metastasis from a pulmonary neuroendocrine tumor. We described lesions of different etiologies in which the T2-weighted imaging profile helped narrow the differential diagnosis and facilitated the definitive diagnosis.