Acta radiologica open最新文献

A nontraumatic and idiopathic spontaneous subcapsular hepatic hematoma is a rare but often fatal condition. Herein, we report a case of nontraumatic progressive massive subcapsular hepatic hematoma that straddled both liver lobes and was successfully treated by repeated arterial embolization. Following treatment, the hematoma did not progress.

Background: Dorsal/volar tilt is an important radiographic measurement commonly included in the treatment decision of distal radius fractures (DRFs). However, studies have shown that forearm positioning relative to rotation (i.e., supination and pronation) can affect the measured tilt value but with substantial interobserver variance.

Purpose: To examine whether interobserver agreement on radiographic tilt measurement is influenced by forearm rotation.

Material and methods: We radiographed 21 cadaveric forearms at 5° rotational intervals between 15° supination and 15° pronation on lateral radiographs. A radiologist and a hand surgeon measured tilt in a blinded and randomized fashion. Bland-Altman analyses with bias and limits of agreement (LoA) were used to estimate interobserver agreement for forearms in all degrees of rotation, non-rotated forearms, supinated forearms, and pronated forearms.

Results: Interobserver agreement varied with forearm rotation. Bias (95% confidence interval [CI]; LoA) was -1.54° (95% CI: -2.53, -0.55; LoA: -13.46, 10.38) when measuring tilt on radiographs with all degrees of forearm rotation, and -1.48° (95% CI: -4.13, 1.17; LoA: -12.88, 9.92) when measuring tilt on true lateral 0° radiographs. When measuring on supinated and pronated radiographs, bias was -0.03° (95% CI: -1.35, 1.29; LoA: -8.34, 8.28) and -3.23° (95% CI: -5.41, -1.06; LoA: -16.90, 10.44), respectively.

Conclusion: Interobserver agreement on tilt was similar when comparing measurements made on true lateral radiographs to those made on the group with all degrees of forearm rotation. However, interobserver agreement improved with supination and worsened with pronation.

Background: The newly adopted European directive DE59/2013 mandates adequate patient information in procedures involving ionising radiation. Patient interest in knowing about their radiation dose and an effective communication method for dose exposure remain poorly investigated.

Purpose: This study is aimed at investigating both patient interest in radiation dose and an effective method to communicate radiation dose exposure.

Material and methods: The present analysis is based on a multi-centre cross-sectional data collection involving 1,084 patients from four different hospitals ‒ two general and two paediatric hospitals. Anonymous questionnaires were administered, consisting of an initial overview of radiation use in imaging procedures, a patient data section, and an explanatory section providing information in four modalities.

Results: 1009 patients were included in the analysis, with 75 refusing participation; 173 participants were relatives of paediatric patients. Initial information provided to patients was considered comprehensible. The information modality with symbols was considered the most readily understandable format by patients, with no appreciable differences in comprehension attributable to social or cultural background. The modality including dose numbers and diagnostic reference levels was preferred by patients with higher socio-economic background. The option 'None of those' was selected by one-third of our sample population, composed of four different clusters: female, over 60 years old, unemployed, and from low socio-economic backgrounds.

Conclusions: This study demonstrated a high level of interest amongst patients in knowing about radiation dose exposure. Pictorial representations were well understood by patients from a variety of different ages and education levels. However, a universally comprehensible model of communicating radiation dose information remains to be elucidated.

Background: A multi detector computed tomography (CT) scanner with wide-area coverage enables whole-brain volumetric scanning in a single rotation.

Purpose: To investigate variations in image-quality characteristics in the longitudinal direction for different image-reconstruction algorithms and strengths with phantoms.

Material and methods: Single-rotation volume scans were performed on a 320-row multidetector CT volume scanner using three types of phantoms. Tube current was set to 200 mA (standard dose) and 50 mA (low dose). All images were reconstructed with filtered back projection (FBP), mild and strong levels with hybrid iterative reconstruction (HIR), and model-based IR (MBIR). Computed tomography numbers, image noise, noise power spectrum (NPS), task-based transfer function (TTF), and visual spatial resolution were used to evaluate uniformity of image quality in the longitudinal direction (Z-axis).

Results: The MBIR images showed smaller variation in CT numbers in the Z-axis. The difference in the highest and lowest CT numbers was smaller (5.0 Hounsfield units [HU]) for MBIR than for FBP (6.6 HU) and HIR (6.8 HU). The variations in image noise were the smallest for strong MBIR and the largest for FBP. The low-frequency component at NPS_0.2 was lower for strong MBIR than for other algorithms. The high-frequency component at NPS_0.8 was low in all reconstructions. For MBIR, the image resolution and TTFs were higher in the outer portion than in the center.

Conclusion: Model-based IR is the optimal image-reconstruction algorithm for single-volume scan of spherical subjects owing to its high in-plane resolution and uniformity of CT numbers, image noise, and NPS in the Z-axis.

Bronchial artery embolization is minimally invasive, has a low complication rate, and achieves good hemorrhage control. It is the first-line treatment in hemoptysis patients whom medications are ineffective. Cerebral infarction is a rare complication of bronchial artery embolization, with posterior circulation infarcts being the most common. Possible mechanisms include a neurotoxic reaction to the contrast medium used, bronchial artery-pulmonary shunt, embolus formation, fistula formation between the bronchial artery and the cerebral artery, and so on. To the best of our knowledge, there have been relatively few reports regarding posterior circulation infarcts after BAE, including 14 cases shown in Table 1. 11 patients recovered well after medical treatment, while the other patients did not survive. We report a case of a patient with a large posterior circulation infarct post bronchial artery embolization who developed severe neurological symptoms and died after 3 months of medication. Conclusion: Posterior circulation infarction is a rare but severe complication of bronchial artery embolization, and measures should be taken to prevent its occurrence.

Background: In suspected community-acquired pneumonia (CAP), chest CT is superior to the routinely obtained radiographs (CXR), but administers higher radiation doses. However, ultra-low-dose CT (ULDCT) has shown promising results.

Purpose: To compare radiation dose and image quality using standard and ULDCT protocols designed for a multicenter study encompassing three CT scanner models from GE, Canon, and Siemens.

Material and methods: Patients with suspected CAP were referred for non-contrast standard dose chest CT (NCCT) and ULDCT. Effective radiation dose and Contrast-to-Noise Ratio (CNR) was calculated.

Results: Mean effective doses were GE (n = 10) 6.93 mSv in NCCT and 0.27 mSv in ULDCT; Canon (n = 9) 3.48 in mSv NCCT and 1.11 mSv in ULDCT; Siemens (n = 10) 2.85 mSv in NCCT and 0.45 mSv in ULDCT. CNR was reduced by 29-39% in ULDCT.

Conclusion: The proposed CT protocols yielded dose reductions of 96%, 68%, and 84% using a GE, Canon, and Siemens scanner, respectively.

Intraductal papillary mucinous neoplasms (IPMN) of the pancreas have the potential for malignant progression into adenocarcinoma. Colloid or mucinous non-cystic carcinoma of the pancreas is an uncommon variant neoplasm that can arise within an intestinal type IPMN and have a relatively improved prognosis but may mimic the more lethal tubular or ductal adenocarcinoma. Colloid carcinoma is an infiltrating ductal epithelial neoplasm containing primarily extracellular stromal mucin pools and scant amount of centrally floating neoplastic cells. While several reports have evaluated the unique pathologic and immunohistochemical profile of colloid carcinomas, there has been limited radiologic-pathologic correlation in the literature. We report a case of an 83-year-old female who presented for evaluation of slowly progressive abdominal pain and was found to have colloid carcinoma arising from an IPMN. This is one of the first reports to correlate the multimodality radiology including cinematic rendering (CR) and histopathology features associated with this tumor. An enhanced understanding of the correlation between imaging appearance and specific histopathologic findings may aid in the early recognition and treatment of this rare neoplasm. Emphasis is placed on CR as this may help guide surgical management.

Background: The European Society of Cardiology has published updated guidelines regarding pathways for diagnosis and management of obstructive coronary artery disease (CAD). Non-invasive functional assessment, for example, by stress perfusion cardiac magnetic resonance (stress pCMR) is recommended in patients with intermediate pretest probability of disease. Previous pCMR studies were mainly performed in high volume university hospitals with experienced radiologists or cardiologists interpreting the images.

Purpose: The aim of the present study was to evaluate the feasibility of establishing a stress pCMR imaging service in a district hospital.

Material and methods: One hundred and thirteen patients with intermediate pretest probability of CAD referred for single-photon emission computed tomography (SPECT) at the regional hospital also underwent adenosine stress pCMR locally. The diagnostic analysis was compared to that of an experienced cardiac magnetic resonance (CMR) center serving as a reference.

Results: Inter-rater agreement between local readers and the reference reader was substantial to perfect for late gadolinium enhancement (LGE) (weighted kappa = 0.76 and 0.82), but only fair to moderate for pCMR (k = 0.34 and 0.51). No improvement in agreement between reference reader and local reader during the study was demonstrated.

Conclusion: CMR is feasible in patients with intermediate pretest probability of obstructive CAD in the setting of a district hospital. However, as opposed to infarct detection with LGE, the interpretation of stress pCMR was more challenging. To establish this method, we suggest obtaining experience in close collaboration with a reference CMR center.

Background: Metal artifact reduction sequence magnetic resonance imaging (MRI) scan is a common method to detect adverse reaction to metal debris in total hip arthroplasty (THA). It might be quicker and cheaper if ultrasonography (US) could screen for the need for an MRI. However, both require trained personnel.

Purpose: We aimed to investigate the sensitivity and specificity of US for detecting pseudotumors (PT) when performed by an orthopedic surgery resident compared to MRI. We also investigated the sensitivity and specificity of US to detect PTs in obese and non-obese patients.

Material and methods: We examined 205 patients with hip resurfacing arthroplasty, metal-on-metal or metal-on-polyethylene THA with both MRI and US. US was performed by an orthopedic surgery resident who was trained according to a standardized training program in musculoskeletal US. Results from MRI were used as gold standard.

Results: US had a sensitivity of 0.92 (95% CI 0.81-0.98) and specificity of 0.94 (95% CI 0.89-0.97) for detecting PT. It had a positive predictive value of 0.84 (95% CI 0.73-0.91) and a negative predictive value of 0.97 (95% CI 0.93-0.99). US performed similarly in obese and non-obese patients.

Conclusions: US had a high sensitivity and specificity for detecting PT when performed by an orthopedic surgery resident. Trained orthopedic surgeons could screen for the need of an MRI scan when searching PTs.

Intussusception refers to invagination of bowel loops into a neighboring, adjacent bowel segment. While it is not an uncommon entity in paediatrics-about 95% of intussusceptions occur in childhood, merely 5% of them affect the adult population. When affecting the later typically the small intestine is engaged rather than the colon. The diagnosis often represents with unspecific symptoms and is rarely considered a possibility in adults. In the past the diagnosis was typically made intraoperatively. As the Multi-Detector Computed Tomography (MDCT) of the abdomen became a referral diagnostic method, recognizing the signs of the condition is very important since some of the cases are transient, while others have an underlying malignant cause and more aggressive treatment is required. Surgical treatment planning is mandatory in those neoplastic complicated cases. The presented case report describes the role of radiology and the surgical treatment of a malignant ileocolic intussusception.