Risk of pseudoaneurysm and bleeding complications after partial nephrectomy: comparison of tumor enucleation to standard margin technique

Partial nephrectomy (PN) is the gold standard for the resection of amenable small renal masses. Some surgeons have adopted tumor enucleation (TE) over the standard margin PN (SPN) technique based on preservation of healthy renal parenchyma by following the tumor pseudocapsule. However, TE may also confer additional advantages due to avoidance of sharp incision including reduction in perioperative and bleeding complications. Therefore, we evaluated the rate of pseudoaneurysms and other complications following TE vs. SPN. A retrospective cohort study of patients undergoing PN (TE and SPN) between 2008 and 2020 was conducted. Baseline characteristics were compared between the TE and SPN cohorts with univariable and multivariable logistic regression models. A total of 534 patients were included, 195 (36.5%) receiving TE and 339 (63.5%) SPN. There were no differences in baseline patient demographics. There was no difference in RENAL nephrometry scores between the two groups (p = 0.47). TE had lower rates of postoperative complications (11.3 vs. 21.5%, p = 0.002). TE had less bleeding complications (2.1 vs. 8.0%, p = 0.002) with no pseudoaneurysm events following TE compared to 12 following SPN (0.0 vs. 3.5%, p = 0.008). Need for interventional radiology largely reflected pseudoaneurysm differences (0 (0.0%) TE vs. 13 (3.8%) SPN, p = 0.006. Readmission occurred less often after TE vs. SPN (4.1 vs. 8.3%, p = 0.07). Patients receiving TE experienced no clinically significant pseudoaneurysm formation and were less likely to have any bleeding complication or major complication postoperatively. TE may be preferred when minimizing morbidity aligns with patient selection and preferences.

Meeting the new joint British Society of Gastrointestinal and Abdominal Radiology and Royal College of Radiologists CT colonography standards: a 6-year experience

AIM

To audit the performance of computed tomography colonography (CTC) at St Mark's Hospital against the joint British Society of Gastrointestinal and Abdominal Radiology (BSGAR) and Royal College of Radiologists (RCR) standards.

MATERIALS AND METHODS

A retrospective audit of all CTC studies between January 2012 to December 2017 was performed against the BSGAR/RCR standards along with additional data outwith the guidelines. Evidence was obtained from a central database, radiology information systems (RISs), picture archiving and communication systems (PACSs), and electronic patient records (EPRs).

RESULTS

Over the 6 years, 13,143 CTCs were performed and 12,996 (99%) were adequate or better. Of the cases 1,867 had a >6 mm polyp or cancer reported (polyp identification rate [PIR] 14%) and the positive predictive value (PPV) was 93% (1,148/1,240). Median radiation dose was 458 mGy·cm, mean additional acquisition rate was 19% (2,505/13,143), subsequent endoscopy rate was 9% (1,222/13,143) and mean interpretation time for a negative study was 34.6 minutes. Nine perforations occurred (perforation rate of 0.068%) and one was symptomatic (symptomatic perforation rate of 0.008%). For suspected cancers, the same-day endoscopy rate was 27% (96/360) and same-day staging rate was 76% (272/360). Post-imaging colorectal cancer rates (PICRC) was 3.06 per 100 cancers detected and 0.23 per 1,000 CTCs. The service was always rated "good" or higher by patients.

CONCLUSION

This audit shows the CTC service at St Mark's Hospital to be safe and of sufficiently high quality to meet the BSGAR/RCR standards with most outcomes equal to or above the aspirational target. Areas for service and individual reader improvement were also identified.

Diagnostic pathways in Crohn's disease

The management of Crohn's disease (CD) is shifting from a stepwise, incremental approach based on symptom control to more aggressive early combined immunosuppression in an attempt to induce remission more rapidly and avoid long-term bowel damage. Accurately defining disease activity is a major challenge, as there is often a disconnect between symptomatology and underlying disease status. The role of imaging in CD has evolved such that it now plays a central role establishing the initial diagnosis, characterising disease phenotype, activity assessment, disease surveillance, and assessing response to therapy. Furthermore, the "treat-to-target" approach is being investigated in CD, with resolution of transmural inflammation on cross-sectional imaging being the treatment goal. In this review, we summarise the principal imaging techniques available to the radiologist, the key findings, and provide some guidance on the preferred imaging option in the diagnostic pathway. We consider the relative merits and drawbacks of each imaging technique before offering a brief discussion of some current developments and research avenues in CD imaging. We discuss how imaging may be useful in a "treat-to-target" approach. Finally, we highlight some practical considerations around service configuration and delivery to optimise imaging in CD in an accurate, cost-effective manner.

Epithelioid angiomyolipoma metastasis to the rectus abdominis

A 37-year-old female presented with abdominal pain. An abdominal computed tomography scan demonstrated a 10 cm x 13 cm left renal mass. An open adrenal-sparing radical nephrectomy was performed. The pathological diagnosis was epithelioid angiomyolipoma. Five-year surveillance did not demonstrate recurrence of disease. However, a 1.8 cm x 2.5 cm mass on the rectus abdominis muscle was identified after 5 years. Biopsy of the mass demonstrated histologic findings consistent with the primary tumor. Herein, we report a case of metastatic renal epithelioid angiomyolipoma to the rectus abdominis muscle more than 5 years after resection of primary renal tumor.

The challenge of segmental small bowel motility quantitation using MR enterography

OBJECTIVE

Analysis of "cine" MRI using segmental regions of interest (ROIs) has become increasingly popular for investigating bowel motility; however, variation in motility in healthy subjects both within and between scans remains poorly described.

METHODS

20 healthy individuals (mean age, 28 years; 14, males) underwent MR enterography to acquire dynamic motility scans in both breath hold (BH) and free breathing (FB) on 2 occasions. Motility data were quantitatively assessed by placing four ROIs per subject in different small bowel segments and applying two measures: (1) contractions per minute (CPM) and (2) Jacobian standard deviation (SD) motility score. Within-scan (between segment) variation was assessed using intraclass correlation (ICC), and repeatability was assessed using Bland-Altman limits of agreement (BA LoA).

RESULTS

Within-scan segmental variation: BH CPM and Jacobian SD metrics between the four segments demonstrated ICC R = 0.06, p = 0.100 and R = 0.20, p = 0.027 and in FB, the CPM and Jacobian SD metrics demonstrated ICC R = -0.26, p = 0.050 and R = 0.19, p = 0.030. Repeatability: BH CPM for matched segments ranged between 0 and 14 contractions with BA LoA of ±8.36 and Jacobian SD ranged between 0.09 and 0.51 with LoA of ±0.33. In FB data, CPM ranged between 0 and 10 contractions with BA LoA of ±7.25 and Jacobian SD ranged between 0.16 and 0.63 with LoA = ±0.28.

CONCLUSION

The MRI-quantified small bowel motility in normal subjects demonstrates wide intersegmental variation and relatively poor repeatability over time.

ADVANCES IN KNOWLEDGE

This article presents baseline values for healthy individuals of within- and between-scan motility that are essential for understanding how this process changes in disease.

200 MeV proton radiography studies with a hand phantom using a prototype proton CT scanner

Proton radiography has applications in patient alignment and verification procedures for proton beam radiation therapy. In this paper, we report an experiment which used 200 MeV protons to generate proton energy-loss and scattering radiographs of a hand phantom. The experiment used the first-generation proton computed tomography (CT) scanner prototype, which was installed on the research beam line of the clinical proton synchrotron at Loma Linda University Medical Center. It was found that while both radiographs displayed anatomical details of the hand phantom, the energy-loss radiograph had a noticeably higher resolution. Nonetheless, scattering radiography may yield more contrast between soft and bone tissue than energy-loss radiography, however, this requires further study. This study contributes to the optimization of the performance of the next-generation of clinical proton CT scanners. Furthermore, it demonstrates the potential of proton imaging (proton radiography and CT), which is now within reach of becoming available as a new, potentially low-dose medical imaging modality.

Development of a Head Scanner for Proton CT

We describe a new head scanner developed for Proton Computed Tomography (pCT) in support of proton therapy treatment planning, aiming at reconstructing an accurate map of the stopping power (S.P.) in a phantom and, in the future, in patients. The system consists of two silicon telescopes which track the proton before and after the phantom/patient, and an energy detector which measures the residual energy or range of the proton to reconstruct the Water Equivalent Path Length (WEPL) in the phantom. Based on the experience of the existing prototype and extensive Geant4 simulations and CT reconstructions, the new pCT scanner will support clinically useful proton fluxes.

An interview study analysing patients' experiences and perceptions of non-laxative or full-laxative preparation with faecal tagging prior to CT colonography

AIM

To compare patients' experiences of either non- or full-laxative bowel preparation with additional faecal tagging and subsequent computed tomographic (CT) colonography using in-depth interviews to elicit detailed responses.

MATERIALS AND METHODS

Patients who received CT colonography after non- (n = 9) or full-laxative (n = 9) preparation participated in a semi-structured telephone interview at least 2 days after the investigation. Full-laxative preparation consisted of magnesium citrate and sodium picosulphate administered at home (or polyethylene glycol, if contraindicated), followed by hospital-based faecal tagging with iohexol. Non-laxative preparation was home-based barium sulphate for faecal tagging. Interviews were transcribed and thematically analysed to identify recurrent themes on patients' perceptions and experiences.

RESULTS

Experiences of full-laxative preparation were usually negative and characterized by pre-test diarrhoea that caused significant interference with daily routine. Post-test flatus was common. Non-laxative preparation was well-tolerated; patients reported no or minimal changes to bowel habit and rapid return to daily routine. Patients reported worry and uncertainty about the purpose of faecal tagging. For iohexol, this also added burden from waiting before testing.

CONCLUSION

Patients' responses supported previous findings that non-laxative preparation is more acceptable than full-laxative preparation but both can be improved. Faecal tagging used in combination with laxative preparation is poorly understood, adding burden and worry. Home-based non-laxative preparation is also poorly understood and patients require better information on the purpose and mechanism in order to give fully informed consent. This may also optimize adherence to instructions. Allowing home-based self-administration of all types of preparation would prevent waiting before testing.

Assessing biological indicators for remediated anthropogenic urban soils

Anthropogenic urban soils, including brownfield soils, are currently characterised and evaluated using mainly physico-chemical properties. Our objective was to determine if biological indicators could provide a more comprehensive soil quality assessment relative to sustainability, identifying contamination issues, and effectiveness of remediation strategies. Plant, invertebrate and microbial assays and functional processes were evaluated at 10 brownfield/anthropogenic urban locations at different stages of remediation in northwest England. Extreme sites were discriminated on the basis of earthworm counts and a small number of indicators likely to be related to their activity. It was concluded that identifying a universally-applicable benchmark suite of biological indicators is very unlikely without considerable advancement of knowledge and technology.