The British Journal of Radiology
ISSN / EISSN : 0007-1285 / 1748-880X
Published by: British Institute of Radiology (10.1259)
Total articles ≅ 28,336
Latest articles in this journal
The British Journal of Radiology; https://doi.org/10.1259/bjr.20210271
Objectives: To compare “black ring-shaped burn” (BRSB) and charring using spectral computed tomography (CT). Methods: Spectral CT was performed using chicken pectoralis minor muscle, processed in three ways and unprocessed as a control: a) BRSB generated by bringing the negative pole surface of a 3 V button battery (BB) into contact with the muscle; b) BRSB caused by a 1.5 V BB; c) charring caused by broiling; and d) control. Attenuation values were compared between BRSB and charring. Muscles were formalin-fixed and stained with Perls’ Prussian blue. Results: Attenuation values from polychromatic 120-kVp images were significantly higher for BRSBs than for charring. In the spectral Hounsfield unit curve, attenuation values for BRSBs were higher for lower energy. Histopathologically, BRSBs stained positively with Perls’ Prussian blue. Conclusions: This study using spectral CT revealed that BRSB contains metal and confirmed the presence of Fe3+ histopathologically. BRSB differs from charring due to burns. Advances in knowledge: The exact composition of BRSB remains unclear, but this report is the first to show that BRSB differs from charring using spectral CT. Clarification of the composition of BRSB is expected to facilitate the development of more effective BRSB removal therapy.
The British Journal of Radiology; https://doi.org/10.1259/bjr.20210819
Objectives: To develop a rapid and accurate 4D deformable image registration (DIR) approach for online adaptive radiotherapy. Methods: We propose a deep learning (DL)-based few-shot registration network (FR-Net) to generate deformation vector fields from each respiratory phase to an implicit reference image, thereby mitigating the bias introduced by the selection of reference images. The proposed FR-Net is pretrained with limited unlabeled 4D data and further optimized by maximizing the intensity similarity of one specific four-dimensional computed tomography (4DCT) scan. Because of the learning ability of DL models, the few-shot learning strategy facilitates the generalization of the model to other 4D data sets and the acceleration of the optimization process. Results: The proposed FR-Net is evaluated for 4D groupwise and 3D pairwise registration on thoracic 4DCT data sets DIR-Lab and POPI. FR-Net displays an averaged target registration error of 1.48 mm and 1.16 mm between the maximum inhalation and exhalation phases in the 4DCT of DIR-Lab and POPI, respectively, with approximately 2 min required to optimize one 4DCT. Overall, FR-Net outperforms state-of-the-art methods in terms of registration accuracy and exhibits a low computational time. Conclusion: We develop a few-shot groupwise DIR algorithm for 4DCT images. The promising registration performance and computational efficiency demonstrate the prospective applications of this approach in registration tasks for online adaptive radiotherapy. Advances in knowledge: This work exploits DL models to solve the optimization problem in registering 4DCT scans while combining groupwise registration and few-shot learning strategy to solve the problem of consuming computational time and inferior registration accuracy.
The British Journal of Radiology; https://doi.org/10.1259/bjr.20210065
Objectives: To determine the diagnostic accuracy and complication rate of percutaneous transthoracic needle biopsy (PTNB) for subsolid pulmonary nodules and sources of heterogeneity among reported results. Methods: We searched PubMed, EMBASE, and Cochrane libraries (until November 7, 2020) for studies measuring the diagnostic accuracy of PTNB for subsolid pulmonary nodules. Pooled sensitivity and specificity of PTNB were calculated using a bivariate random-effects model. Bivariate meta-regression analyses were performed to identify sources of heterogeneity. Pooled overall and major complication rates were calculated. Results: We included 744 biopsies from 685 patients (12 studies). The pooled sensitivity and specificity of PTNB for subsolid nodules were 90% (95% confidence interval [CI]: 85–94%) and 99% (95% CI: 92–100%), respectively. Mean age above 65 years was the only covariate significantly associated with higher sensitivity (93% vs 85%, p = 0.04). Core needle biopsy showed marginally higher sensitivity than fine-needle aspiration (93% vs 83%, p = 0.07). Pooled overall and major complication rate of PTNB were 43% (95% CI: 25–62%) and 0.1% (95% CI: 0–0.4%), respectively. Major complication rate was not different between fine-needle aspiration and core needle biopsy groups (p = 0.25). Conclusion: PTNB had acceptable performance and a low major complication rate in diagnosing subsolid pulmonary nodules. The only significant source of heterogeneity in reported sensitivities was a mean age above 65 years. Advances in knowledge: This is the first meta-analysis attempting to systemically determine the cause of heterogeneity in the diagnostic accuracy and complication rate of PTNB for subsolid pulmonary nodules.
The British Journal of Radiology; https://doi.org/10.1259/bjr.20210785
Objective: The current study was carried out to assess the value of positron emission tomography (PET)/CT on the diagnosis and staging of primary musculoskeletal tumors. Methods: PET–CT test results and histopathological study reports of all the patients with primary musculoskeletal tumors in our department from January 2006 to July 2015 were retrospectively reviewed. Maximum standardized uptake value (SUVmax) in these PET–CT reports were recorded and analyzed respectively for each type of sarcoma. Results: A total of 255 patients were included in the final analysis. Sensitivity of SUVmax based diagnosis was 96.6% for primary malignant osseous sarcomas and 91.2% for soft tissue sarcomas. SUVmax of high-grade osseous sarcomas (average 8.4 ± 5.5) was significantly higher (p < 0.001) than low-grade osseous sarcomas (average 3.9 ± 1.8); based on current case series, SUVmax of high-grade soft tissue sarcomas (7.5 ± 5.1) was not significantly different (p = 0.229) from that of low-grade soft tissue sarcomas (5.3 ± 3.7). Significant decrease of SUVmax value after chemotherapy was associated with favorable prognosis in patients with osteosarcoma. Conclusion: Results of the current study indicate that, the SUVmax based application of PET–CT can be a valuable supplementary method to histopathological tests regarding the diagnosis and staging of primary musculoskeletal sarcomas. Advances in knowledge: SUVmax based application of PET–CT is a highly sensitive method in diagnosis of primary osseous and soft tissue sarcomas in Chinese patients.
The British Journal of Radiology; https://doi.org/10.1259/bjr.20210428
Objective: To perform a literature review assessing role of MRI in predicting origin of indeterminate uterocervical carcinomas with emphasis on sequences and imaging parameters. Methods: Electronic literature search of PubMed was performed from its inception until May 2020 and PICO model used for study selection; population was female patients with known/clinical suspicion of uterocervical cancer, intervention was MRI, comparison was by histopathology and outcome was differentiation between primary endometrial and cervical cancers. Results: Eight out of 9 reviewed articles reinforced role of MRI in uterocervical primary determination. T2 and Dynamic contrast were the most popular sequences determining tumor location, morphology, enhancement, and invasion patterns. Role of DWI and MR spectroscopy has been evaluated by even fewer studies with significant differences found in both apparent diffusion coefficient values and metabolite spectra. The four studies eligible for meta-analysis showed a pooled sensitivity of 88.4% (95% confidence interval 70.6 to 96.1%) and a pooled specificity of 39.5% (95% confidence interval 4.2 to 90.6%). Conclusions: MRI plays a pivotal role in uterocervical primary determination with both conventional and newer sequences assessing important morphometric and functional parameters. Socioeconomic impact of both primaries, different management guidelines and paucity of existing studies warrants further research. Prospective multicenter trials will help bridge this gap. Meanwhile, individual patient database meta-analysis can help corroborate existing data. Advances in knowledge: MRI with its classical and functional sequences helps in differentiation of the uterine ‘cancer gray zone’ which is imperative as both primary endometrial and cervical tumors have different management protocols.
The British Journal of Radiology; https://doi.org/10.1259/bjr.20210555
Objectives: Adrenal adenoma with myelolipomatous degeneration (AMD) is a rarely reported and often overlooked entity. The aim of this study is to improve understanding of these lesions by characterizing the imaging findings with pathologic and clinical correlation. Methods: In the largest series to date, we report 11 nodules in 11 patients confirmed with a pathologic diagnosis of AMD. The available cross-sectional imaging and histopathologic features were reviewed by two radiologists and two pathologists, respectively. Clinical and laboratory data for each patient were obtained from the electronic medical records, when available. Results: All 11 patients had a CT prior to resection or biopsy of the adrenal nodule, with five having received an adrenal mass protocol study. An MRI was available in three patients. The median size of the nodules on imaging was 4.5 cm (range 2.8–8.7) and all but one had macroscopic fat. The largest focus of macroscopic fat had a median size of 0.7 cm (range 0.2–1.6) and on average was 14.4% the size of the tumor, using greatest dimensions. Four (36.4%) patients had a diagnosis of Cushing syndrome prior to nodule resection. Conclusions: Not all adrenal nodules with macroscopic fat on imaging are pure myelolipomas. An AMD should be considered, especially if the foci of fat are small and other features an adenoma are present. Some may also be associated with Cushing syndrome. Advances in knowledge: Myelolipomatous degeneration within an adrenal adenoma has only rarely been previously reported with very few reports emphasizing the imaging features. There may be an association with cortisol hypersecretion and improved recognition of this entity could lead to changes in clinical management.
The British Journal of Radiology; https://doi.org/10.1259/bjr.20210084
Objective: To assess accuracy of dual-energy computed tomography (DECT) to differentiate uric acid from calcium urinary stones in dual-energy split filter vs sequential-spiral vs dual-source acquisition. Methods: Thirty-four urinary stones (volume 89.0 ± 77.4 mm³; 17 calcium stones, 17 uric acid stones) were scanned in a water-filled phantom using a split-filter equipped CT scanner (SOMATOM Definition Edge, Siemens Healthineers, Forchheim, Germany) in split-filter mode at 120 kVp and sequential-spiral mode at 80 and 140 kVp. Additional DE scans were acquired at 80 and 140 kVp (tin filter) with a dual-source CT scanner (SOMATOM Definition FLASH, Siemens Healthineers). Scans were performed with a CTDIvol of 7.3 mGy in all protocols. Urinary stone categorization was based on dual energy ratio (DER) using an automated 3D segmentation. As reference standard, infrared spectroscopy was used to determine urinary stone composition. Results: All three DECT techniques significantly differentiated between uric acid and calcium stones by attenuation values and DERs (p < 0.001 for all). Split-filter DECT provided higher DERs for uric acid stones, when compared with dual-source and sequential-spiral DECT, and lower DERs for calcified stones when compared with dual-source DECT (p < 0.001 for both), leading to a decreased accuracy for material differentiation. Conclusion: Split-filter DECT, sequential-spiral DECT and dual-source DECT all allow for the acquisition of DER to classify urinary stones. Advances in knowledge: Split-filter DECT enables the differentiation between uric acid and calcium stones despite decreased spectral separation when compared with dual-source and dual-spiral DECT.
The British Journal of Radiology; https://doi.org/10.1259/bjr.20210311
Primary aldosteronism (PA) is the primary cause of secondary hypertension. The prevalence of PA has probably been underestimated in the past and recent studies suggest that PA could be present in up to 10% of patients suffering from hypertension. Aldosterone excess in PA can be caused by unilateral adrenal disease, usually adrenal adenoma, or bilateral adrenal hyperplasia. Differentiation between unilateral and bilateral disease is clinically important as the former can effectively be treated by removal of the affected adrenal. CT or MRI cannot reliably distinguish unilateral from bilateral disease. Therefore, adrenal vein sampling (AVS) is an important step of the diagnostic work-up in patients with PA. Current guidelines recommend PA in virtually all patients with biochemically diagnosed PA who would undergo adrenal surgery if unilateral PA was diagnosed. In this narrative review, we give an overview of the current technique used for AVS with a focus on the experience with this technique at the University Hospital Basel, Switzerland.
The British Journal of Radiology; https://doi.org/10.1259/bjr.20210825
T2-FLAIR mismatch sign has been advocated to be 100% specific for IDH-mutant 1p/19q non-codeleted gliomas (diffuse astrocytomas). However, false positives have been reported in recent works. Loose application of the criteria may lead to erroneous classification, especially by non-trained neuroradiologists. In this pictorial essay, we aim to bring attention to the need for strict criteria for the application of T2-FLAIR mismatch sign and to discuss the potential pitfalls in the application of these criteria. For that, a series of adult brain tumour cases are presented to demonstrate how to apply this radiological sign in the clinical practice.
The British Journal of Radiology; https://doi.org/10.1259/bjr.20210727
Objective: Implementing a streamlined interventional radiology (IR) service in the UK has been a challenge. This study aims to review a set of changes introduced in IR at a tertiary centre, including a new referral process and the designation of IR clinical nurse specialists. Methods: A new process of referring patients to IR using a single generic referral pathway was implemented, replacing an order dropdown-based system. A qualitative survey was designed and distributed as a single-use web link in order to assess the satisfaction and impact of this new process. Responses were based on Likert scale and pertained to perceived qualities of the new referral process. Data analysis was performed to identify specialty and grade-specific trends and possible differences amongst groups. Results: Findings from 98 respondents revealed a strong overall satisfaction with the new referral method and support for its continuation. Subgroup analysis by specialty, concluded medical specialties rated the new referral system more favourably than surgical specialties across all aspects: time efficiency, ease of use, periprocedural support and overall user experience. The new system also increased departmental productivity with an increase in the number of patients treated by 11.2%. Conclusion: Micropolicy changes within individual IR departments such as the replacement of a request-based referral system to one which puts IR in control of vetting and patient flow is one of many changes that reinforce the transformational phase of this specialty. Advances in knowledge: Micropolicy changes within IR departments are key in the progression and widespread recognition of the specialty.