Browsing by Author "Curvo-Semedo, L"
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- Congenital cystic lesions of the biliary treePublication . Santiago, I; Loureiro, R; Curvo-Semedo, L; Marques, C; Tardáguila, F; Matos, C; Caseiro-Alves, FOBJECTIVE: The purpose of this essay is to illustrate the imaging findings of congenital cystic lesions of the biliary tract. CONCLUSION: Congenital cystic lesions of the biliary tract include ductal plate malformations and choledochal cysts and can be recognized with characteristic imaging findings and basic knowledge of the embryologic development of the biliary tree.
- Imaging the postoperative patient: long-term complications of gastrointestinal surgeryPublication . Ramos-Andrade, D; Andrade, L; Ruivo, C; Portilha, MA; Caseiro-Alves, F; Curvo-Semedo, LThe objectives of this review are (1) to become acquainted with the long-term complications of surgery of the gastrointestinal tract, and (2) to appreciate the appropriate use of imaging in the assessment of long-term complications.
- Multiple penetrating atherosclerotic ulcers: Case 8036Publication . Santiago, I; Seco, M; Curvo-Semedo, L
- One-shot diagnostic and prognostic assessment in intermediate- to high-risk acute pulmonary embolism: The role of multidetector computed tomographyPublication . Baptista, R; Santiago, I; Jorge, E; Teixeira, R; Mendes, P; Curvo-Semedo, L; Castro, G; Monteiro, P; Caseiro-Alves, F; Providência, LAINTRODUCTION: Contrast-enhanced multidetector computed tomography (MDCT) is useful for the diagnosis of pulmonary embolism (PE). However, current guidelines do not support its use for risk assessment in acute PE patients. OBJECTIVES: We compared the prognostic impact of MDCT-derived indices regarding medium-term mortality in a population of intermediate- to high-risk PE patients, mostly treated by thrombolysis. METHODS: Thirty-nine consecutive patients admitted to an intensive care unit with acute PE were studied. All patients had a pulmonary MDCT on admission to the emergency room as part of the diagnostic algorithm. We assessed the following MDCT variables: right ventricular/left ventricular diameter (RV/LV) ratio, arterial obstruction index, pulmonary artery-to-aorta diameter ratio and azygos vein diameter. A 33-month follow-up was performed. RESULTS: Mean age was 59.1±19.6 years, with 80% of patients receiving thrombolysis. Follow-up all-cause mortality was 12.8%. Of the MDCT-derived variables, only the RV/LV ratio had significant predictive value, being higher in patients who suffered the endpoint (1.6±0.5 vs. 1.9±0.4, p=0.046). Patients with an RV/LV ratio ≥1.8 had 11-fold higher medium-term all-cause mortality (3.8% vs. 38.8%, p<0.001). Regarding this endpoint, the c-statistic was 0.78 (95% CI, 0.60-0.96) for RV/LV ratio and calibration was good (goodness-of-fit p=0.594). No other radiological index was predictive of mortality. CONCLUSIONS: MDCT gives the possibility, in a single imaging procedure, of diagnosing and assessing the prognosis of patients with intermediate- to high-risk PE. Although further studies are needed, the simple-to-calculate RV/LV ratio has good discrimination and calibration for predicting poorer outcomes in patients with acute PE.
- Plasmocitoma da coluna lombarPublication . Andrade, DR; Magalhães, M; Andrade, LC; Curvo-Semedo, L; Caseiro-Alves, FSolitary bone plasmacytoma is a plasma cell disorder characterized by the formation of a single tumor in the bone. Most commonly, the tumor develops in the spine, and is progressively less frequent in the pelvis, ribs, upper extremities, skull, femur and sternum. Symptoms are mainly local. In most cases, multiple myeloma ensues, conferring it a poor prognosis. The authors describe the case of a 53-year-old male patient who presented with persistent low back pain without apparent cause until a radiography of the lumbar spine was performed. It revealed a lytic lesion, which was proven to be a plasmacytoma after a computed tomography guided biopsy.
- Sigmoid colon perforation at CT colonography secondary to a possible obstructive mechanism: report of a casePublication . Belo-Oliveira, P; Curvo-Semedo, L; Rodrigues, H; Belo-Soares, P; Caseiro-Alves, FWe report a case of colonic perforation in CT colonography, which was observed in a sigmoid colon segment contained within an inguinal hernia. At surgery, apart from the perforation, a normal large-bowel wall was found. Although rare, perforation may occur in patients with normal bowel wall, possibly resulting from a mechanical strain caused by gaseous overdistention. Radiologists performing the procedure must be aware of this possibility
- Soft-tissue foreign body (cactus thorn)Publication . Brito, J; Neves, S; Curvo-Semedo, L; Caseiro-Alves, FA 52-year-old woman complained of pain, swelling and functional impairment on the second digit of the hand 6 weeks after she punctured the finger with a cactus thorn.
- The hypointense liver lesion on T2-weighted MR images and what it meansPublication . Curvo-Semedo, L; Brito, JB; Seco, MF; Costa, JM; Marques, CB; Caseiro-Alves, FThe vast majority of focal liver lesions are hyperintense on T2-weighted magnetic resonance (MR) images. Rarely, however, hepatic nodules may appear totally or partially hypointense on those images. Causes for this uncommon appearance include deposition of iron, calcium, or copper and are related to the presence of blood degradation products, macromolecules, coagulative necrosis, and other conditions. Although rare, low signal intensity relative to surrounding liver on T2-weighted images may be seen in a wide spectrum of lesions. Examples include cases of focal nodular hyperplasia, hepatocellular adenoma, hepatocellular carcinoma, metastases, leiomyoma, siderotic or dysplastic nodules, nodules in Wilson disease, granuloma, and hydatid cyst. On fat-suppressed T2-weighted images, nodules with a lipomatous component, such as lipoma, angiomyolipoma, hepatocellular adenoma, and hepatocellular carcinoma may also appear partially or totally hypointense. The conjunction of other MR imaging findings and their integration in the clinical setting may allow a correct diagnosis in a considerable proportion of cases. The cause for T2-weighted hypointensity may not be, however, always recognized, and only pathologic correlation may provide the answer. The aims of this work are to discuss the causes and mechanisms of hypointensity of liver lesions on T2-weighted images and proposing an algorithm for classification that may be useful as a quick reminder for the interested reader.
- Tuberculosis of the chestPublication . Curvo-Semedo, L; Teixeira, L; Caseiro-Alves, FThe relationship between tuberculosis and mankind has been known for many centuries, with the disease being one of the major causes of illness and death. During the early 1980s, there was a widespread belief that the disease was being controlled, but by the mid-1980s, the number of cases increased. This change in the epidemiological picture has several causes, of which the AIDS epidemic, the progression of poverty in developing countries, the increase in the number of elderly people with an altered immune status and the emergence of multidrug-resistant tuberculosis are the most important. Mainly due to this epidemiological change, the radiological patterns of the disease are also being altered, with the classical distinction between primary and postprimary disease fading and atypical presentations in groups with an altered immune response being increasingly reported. Therefore, the radiologist must be able not only to recognize the classical features of primary and postprimary tuberculosis but also to be familiar with the atypical patterns found in immuno-compromised and elderly patients, since an early diagnosis is generally associated with a greater therapeutic efficacy. Radiologists are, in this way, presented with a new challenge at the beginning of this millennium.
- Tumour ADC measurements in rectal cancer: effect of ROI methods on ADC values and interobserver variabilityPublication . Lambregts, DM; Beets, GL; Maas, M; Curvo-Semedo, L; Kessels, AG; Thywissen, T; Beets-Tan, RGOBJECTIVES: To assess the influence of region of interest (ROI) size and positioning on tumour ADC measurements and interobserver variability in patients with locally advanced rectal cancer (LARC). METHODS: Forty-six LARC patients were retrospectively included. Patients underwent MRI including DWI (b0,500,1000) before and 6-8 weeks after chemoradiation (CRT). Two readers measured mean tumour ADCs (pre- and post-CRT) according to three ROI protocols: whole-volume, single-slice or small solid samples. The three protocols were compared for differences in ADC, SD and interobserver variability (measured as the intraclass correlation coefficient; ICC). RESULTS: ICC for the whole-volume ROIs was excellent (0.91) pre-CRT versus good (0.66) post-CRT. ICCs were 0.53 and 0.42 for the single-slice ROIs versus 0.60 and 0.65 for the sample ROIs. Pre-CRT ADCs for the sample ROIs were significantly lower than for the whole-volume or single-slice ROIs. Post-CRT there were no significant differences between the whole-volume ROIs and the single-slice or sample ROIs, respectively. The SDs for the whole-volume and single-slice ROIs were significantly larger than for the sample ROIs. CONCLUSIONS: ROI size and positioning have a considerable influence on tumour ADC values and interobserver variability. Interobserver variability is worse after CRT. ADCs obtained from the whole tumour volume provide the most reproducible results. Key Points • ROI size and positioning influence tumour ADC measurements in rectal cancer • ROI size and positioning influence interobserver variability of tumour ADC measurements • ADC measurements of the whole tumour volume provide the most reproducible results • Tumour ADC measurements are more reproducible before, rather than after, chemoradiation treatment • Variations caused by ROI size and positioning should be taken into account when using ADC as a biomarker for tumour response.