Publications by authors named "Navin Ramachandran"

18 Publications

  • Page 1 of 1

Impact of the first surge of the COVID-19 pandemic on a tertiary referral centre for kidney cancer.

BJU Int 2021 May 8. Epub 2021 May 8.

Specialist Centre for Kidney Cancer, Royal Free London NHS Foundation Trust, London, UK.

Objective: To analyse the impact of the COVID-19 pandemic on a centralized specialist kidney cancer care pathway.

Materials And Methods: We conducted a retrospective analysis of patient and pathway characteristics including prioritization strategies at the Specialist Centre for Kidney Cancer located at the Royal Free London NHS Foundation Trust (RFH) before and during the surge of COVID-19.

Results: On 18 March 2020 all elective surgery was halted at RFH to redeploy resources and staff for the COVID-19 surge. Prioritizing of patients according to European Association of Urology guidance was introduced. Clinics and the specialist multidisciplinary team (SMDT) meetings were maintained with physical distancing, kidney surgery was moved to a COVID-protected site, and infection prevention measurements were enforced. During the 7 weeks of lockdown (23 March to 10 May 2020), 234 cases were discussed at the SMDT meetings, 53% compared to the 446 cases discussed in the 7 weeks pre-lockdown. The reduction in referrals was more pronounced for small and asymptomatic renal masses. Of 62 low-priority cancer patients, 27 (43.5%) were deferred. Only one (4%) COVID-19 infection occurred postoperatively, and the patient made a full recovery. No increase in clinical or pathological upstaging could be detected in patients who underwent deferred surgery compared to pre-COVID practice.

Conclusion: The first surge of the COVID-19 pandemic severely impacted diagnosis, referral and treatment of kidney cancer at a tertiary referral centre. With a policy of prioritization and COVID-protected pathways, capacity for time-sensitive oncological interventions was maintained and no immediate clinical harm was observed.
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http://dx.doi.org/10.1111/bju.15441DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8239749PMC
May 2021

Mixed acinar and macrocystic ductal prostatic adenocarcinoma.

Lancet Oncol 2021 01;22(1):e37

Department of Urology, University College London Hospital NHS Foundation Trust, London, UK; Division of Surgery & Interventional Science, University College London, London, UK.

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http://dx.doi.org/10.1016/S1470-2045(20)30435-6DOI Listing
January 2021

Prostate Radiofrequency Focal Ablation (ProRAFT) Trial: A Prospective Development Study Evaluating a Bipolar Radiofrequency Device to Treat Prostate Cancer.

J Urol 2021 04 14;205(4):1090-1099. Epub 2020 Dec 14.

Division of Surgery and Interventional Sciences, University College London, London, United Kingdom.

Purpose: We determined the early efficacy of bipolar radiofrequency ablation with a coil design for focal ablation of clinically significant localized prostate cancer visible at multiparametric magnetic resonance imaging.

Materials And Methods: A prospective IDEAL phase 2 development study (Focal Prostate Radiofrequency Ablation, NCT02294903) recruited treatment-naïve patients with a single focus of significant localized prostate cancer (Gleason 7 or 4 mm or more of Gleason 6) concordant with a lesion visible on multiparametric magnetic resonance imaging. Intervention was a focal ablation with a bipolar radiofrequency system (Encage™) encompassing the lesion and a predefined margin using nonrigid magnetic resonance imaging-ultrasound fusion. Primary outcome was the proportion of men with absence of significant localized disease on biopsy at 6 months. Trial followup consisted of serum prostate specific antigen, multiparametric magnetic resonance imaging at 1 week, and 6 and 12 months post-ablation. Validated patient reported outcome measures for urinary, erectile and bowel functions, and adverse events monitoring system were used. Analyses were done on a per-protocol basis.

Results: Of 21 patients recruited 20 received the intervention. Baseline characteristics were median age 66 years (IQR 63-69) and preoperative median prostate specific antigen 7.9 ng/ml (5.3-9.6). A total of 18 patients (90%) had Gleason 7 disease with median maximum cancer 7 mm (IQR 5-10), for a median of 2.8 cc multiparametric magnetic resonance imaging lesions (IQR 1.4-4.8). Targeted biopsy of the treated area (median number of cores 6, IQR 5-8) showed absence of significant localized prostate cancer in 16/20 men (80%), concordant with multiparametric magnetic resonance imaging. There was a low profile of side effects at patient reported outcome measures analysis and there were no serious adverse events.

Conclusions: Focal therapy of significant localized prostate cancer associated with a magnetic resonance imaging lesion using bipolar radiofrequency showed early efficacy to ablate cancer with low rates of genitourinary and rectal side effects.
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http://dx.doi.org/10.1097/JU.0000000000001567DOI Listing
April 2021

Designing a Distributed Ledger Technology System for Interoperable and General Data Protection Regulation-Compliant Health Data Exchange: A Use Case in Blood Glucose Data.

J Med Internet Res 2019 06 14;21(6):e13665. Epub 2019 Jun 14.

Centre for Health Informatics & Multiprofessional Education, University College London, London, United Kingdom.

Background: Distributed ledger technology (DLT) holds great potential to improve health information exchange. However, the immutable and transparent character of this technology may conflict with data privacy regulations and data processing best practices.

Objective: The aim of this paper is to develop a proof-of-concept system for immutable, interoperable, and General Data Protection Regulation (GDPR)-compliant exchange of blood glucose data.

Methods: Given that there is no ideal design for a DLT-based patient-provider data exchange solution, we proposed two different variations for our proof-of-concept system. One design was based purely on the public IOTA distributed ledger (a directed acyclic graph-based DLT) and the second used the same public IOTA ledger in combination with a private InterPlanetary File System (IPFS) cluster. Both designs were assessed according to (1) data reversal risk, (2) data linkability risks, (3) processing time, (4) file size compatibility, and (5) overall system complexity.

Results: The public IOTA design slightly increased the risk of personal data linkability, had an overall low processing time (requiring mean 6.1, SD 1.9 seconds to upload one blood glucose data sample into the DLT), and was relatively simple to implement. The combination of the public IOTA with a private IPFS cluster minimized both reversal and linkability risks, allowed for the exchange of large files (3 months of blood glucose data were uploaded into the DLT in mean 38.1, SD 13.4 seconds), but involved a relatively higher setup complexity.

Conclusions: For the specific use case of blood glucose explored in this study, both designs presented a suitable performance in enabling the interoperable exchange of data between patients and providers. Additionally, both systems were designed considering the latest guidelines on personal data processing, thereby maximizing the alignment with recent GDPR requirements. For future works, these results suggest that the conflict between DLT and data privacy regulations can be addressed if careful considerations are made regarding the use case and the design of the data exchange system.
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http://dx.doi.org/10.2196/13665DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6595943PMC
June 2019

Targeted biopsy of the prostate: does this result in improvement in detection of high-grade cancer or the occurrence of the Will Rogers phenomenon?

BJU Int 2019 May 13. Epub 2019 May 13.

Division of Surgery, Department of Surgery and Cancer, Faculty of Medicine, Imperial College London, London, UK.

Objective: To investigate whether patients with Gleason 3 + 4 cancer on transrectal biopsy are upgraded after undergoing transperineal magnetic resonance imaging (MRI)-targeted biopsy and whether this has implications for current clinical practice.

Patients And Methods: In this retrospective analysis we examined 107 consecutive patients presenting at a single tertiary referral centre (July 2012 to July 2016) with prostate cancer of Gleason score 3 + 4 on transrectal ultrasonography (TRUS)-guided systematic non-targeted biopsy who then underwent a multiparametric MRI followed by MRI-targeted transperineal prostate biopsy for accurate risk stratification and localization.

Results: The patients' mean (sd) age was 67.0 (8.0) years, and they had a median (interquartile range) PSA concentration of 6.2 (4.7-9.6) ng/mL. Of the 107 patients, 84 (78.5%) had Gleason 3 + 4 on both transrectal systematic biopsy and transperineal MRI-targeted biopsy. Nineteen patients (17.8%) were upgraded to Gleason 4 + 3, three patients (3.0%) to Gleason 4 + 4 and one patient (1.0%) to Gleason 4 + 5. These differences were significant (P = 0.0006). Likewise, 23/107 patients (22%) had higher-risk disease based on their targeted biopsies.

Conclusion: The use of targeted biopsy in men with impalpable cancer, ultimately upgraded one in five patients from favourable-intermediate- to unfavourable-intermediate-risk disease or worse. This has significant clinical implications for men considering active surveillance or radical treatment. Our risk calculators must now be validated using these data from targeted biopsy as the technique becomes widely adopted.
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http://dx.doi.org/10.1111/bju.14806DOI Listing
May 2019

Multiparametric whole-body 3.0-T MRI in newly diagnosed intermediate- and high-risk prostate cancer: diagnostic accuracy and interobserver agreement for nodal and metastatic staging.

Eur Radiol 2019 Jun 5;29(6):3159-3169. Epub 2018 Dec 5.

UCL Centre for Medical Imaging, 2nd Floor Charles Bell House, 43 - 45 Foley Street, London, W1W 7TS, UK.

Objectives: To determine the diagnostic accuracy and interobserver concordance of whole-body (WB)-MRI, vs. Tc bone scintigraphy (BS) and fluoro-ethyl-choline (F-choline) PET/CT for the primary staging of intermediate/high-risk prostate cancer.

Methods: An institutional review board approved prospective cohort study carried out between July 2012 and November 2015, whereby 56 men prospectively underwent 3.0-T multiparametric (mp)-WB-MRI in addition to BS (all patients) ± F-choline PET/CT (33 patients). MRI comprised pre- and post-contrast modified Dixon (mDixon), T2-weighted (T2W) imaging, and diffusion-weighted imaging (DWI). Patients underwent follow-up mp-WB-MRI at 1 year to derive the reference standard. WB-MRIs were reviewed by two radiologists applying a 6-point scale and a locked sequential read (LSR) paradigm for the suspicion of nodal (N) and metastatic disease (M1a and M1b).

Results: The mean sensitivity/specificity of WB-MRI for N1 disease was 1.00/0.96 respectively, compared with 1.00/0.82 for F-choline PET/CT. The mean sensitivity and specificity of WB-MRI, F-choline PET/CT, and BS were 0.90/0.88, 0.80/0.92, and 0.60/1.00 for M1b disease. ROC-AUC did not show statistically significant improvement for each component of the LSR; mean ROC-AUC 0.92, 0.94, and 0.93 (p < 0.05) for mDixon + DWI, + T2WI, and + contrast respectively. WB-MRI had an interobserver concordance (κ) of 0.79, 0.68, and 0.58 for N1, M1a, and M1b diseases respectively.

Conclusions: WB-MRI provides high levels of diagnostic accuracy for both nodal and metastatic bone disease, with higher levels of sensitivity than BS for metastatic disease, and similar performance to F-choline PET/CT. T2 and post-contrast mDixon had no significant additive value above a protocol comprising mDixon and DWI alone.

Key Points: • A whole-body MRI protocol comprising unenhanced mDixon and diffusion-weighted imaging provides high levels of diagnostic accuracy for the primary staging of intermediate- and high-risk prostate cancer. • The diagnostic accuracy of whole-body MRI is much higher than that of bone scintigraphy, as currently recommended for clinical use. • Staging using WB-MRI, rather than bone scintigraphy, could result in better patient stratification and treatment delivery than is currently provided to patients worldwide.
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http://dx.doi.org/10.1007/s00330-018-5813-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6510859PMC
June 2019

Authenticating Health Activity Data Using Distributed Ledger Technologies.

Comput Struct Biotechnol J 2018 17;16:257-266. Epub 2018 Jul 17.

University College London, Centre for Health Informatics & Multiprofessional Education, London, United Kingdom.

The on-demand digital healthcare ecosystem is on the near horizon. It has the potential to extract a wealth of information from "big data" collected at the population level, to enhance preventive and precision medicine at the patient level. This may improve efficiency and quality while decreasing cost of healthcare delivered by professionals. However, there are still security and privacy issues that need to be addressed before algorithms, data, and models can be mobilized safely at scale. In this paper we discuss how distributed ledger technologies can play a key role in advancing electronic health, by ensuring authenticity and integrity of data generated by wearable and embedded devices. We demonstrate how the Masked Authenticated Messaging extension module of the IOTA protocol can be used to securely share, store, and retrieve encrypted activity data using a tamper-proof distributed ledger.
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http://dx.doi.org/10.1016/j.csbj.2018.06.004DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6071583PMC
July 2018

The CADMUS trial - Multi-parametric ultrasound targeted biopsies compared to multi-parametric MRI targeted biopsies in the diagnosis of clinically significant prostate cancer.

Contemp Clin Trials 2018 03 3;66:86-92. Epub 2017 Nov 3.

Division of Surgery, Department of Surgery and Cancer, Imperial College London, United Kingdom; Division of Surgery and Interventional Sciences, University College London, United Kingdom.

Objective: To compare the proportion of clinically significant prostate cancers (PCa) found in lesions detected by multiparametric MRI (mpMRI) with that found in lesions detected by multiparametric ultrasound (mpUSS), in men at risk.

Patients And Methods: CADMUS (Cancer Detection by Multiparametric Ultrasound of the prostate) is a prospective, multi-centre paired cohort diagnostic utility study with built-in randomisation of order of biopsies. The trial is registered ISRCTN38541912. All patients will undergo the index test under evaluation (mpUSS±biopsies), as well as the standard test (mpMRI±biopsies). Eligible men will be those at risk of harbouring prostate cancer usually recommended for prostate biopsy, either for the first time or as a repeat, who have not had any prior treatment for prostate cancer. Men in need of repeat biopsy will include those with prior negative results but ongoing suspicion, and those with an existing prostate cancer diagnosis but a need for accurate risk stratification. Both scans will be reported blind to the results of the other and the order in which the targeted biopsies derived from the two different imaging modalities are taken will be randomised. Comparison will be drawn between biopsy results of lesions detected by mpUSS with those lesions detected by mpMRI. Agreement over position between the two imaging modalities will be studied.

Discussion: CADMUS will provide level one evidence on the performance of mpUSS derived targeted biopsies in the identification of clinically significant prostate cancer in comparison to mpMRI targeted biopsies. Recruitment is underway and expected to complete in 2018.
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http://dx.doi.org/10.1016/j.cct.2017.10.011DOI Listing
March 2018

Project PEACH at UCLH: Student Projects in Healthcare Computing.

Stud Health Technol Inform 2017 ;235:288-292

University College London, London.

A collaboration between clinicians at UCLH and the Dept of Computer Science at UCL is giving students of computer science the opportunity to undertake real healthcare computing projects as part of their education. This is enabling the creation of a significant research computing platform within the Trust, based on open source components and hosted in the cloud, while providing a large group of students with experience of the specific challenges of health IT.
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October 2017

The PICTURE study: diagnostic accuracy of multiparametric MRI in men requiring a repeat prostate biopsy.

Br J Cancer 2017 Apr 28;116(9):1159-1165. Epub 2017 Mar 28.

Division of Surgery and Interventional Science, University College London, Faculty of Medical Sciences, 21 University Street, London WC1E 7PN, UK.

Background: Transrectal prostate biopsy has limited diagnostic accuracy. Prostate Imaging Compared to Transperineal Ultrasound-guided biopsy for significant prostate cancer Risk Evaluation (PICTURE) was a paired-cohort confirmatory study designed to assess diagnostic accuracy of multiparametric magnetic resonance imaging (mpMRI) in men requiring a repeat biopsy.

Methods: All underwent 3 T mpMRI and transperineal template prostate mapping biopsies (TTPM biopsies). Multiparametric MRI was reported using Likert scores and radiologists were blinded to initial biopsies. Men were blinded to mpMRI results. Clinically significant prostate cancer was defined as Gleason ⩾4+3 and/or cancer core length ⩾6 mm.

Results: Two hundred and forty-nine had both tests with mean (s.d.) age was 62 (7) years, median (IQR) PSA 6.8 ng ml (4.98-9.50), median (IQR) number of previous biopsies 1 (1-2) and mean (s.d.) gland size 37 ml (15.5). On TTPM biopsies, 103 (41%) had clinically significant prostate cancer. Two hundred and fourteen (86%) had a positive prostate mpMRI using Likert score ⩾3; sensitivity was 97.1% (95% confidence interval (CI): 92-99), specificity 21.9% (15.5-29.5), negative predictive value (NPV) 91.4% (76.9-98.1) and positive predictive value (PPV) 46.7% (35.2-47.8). One hundred and twenty-nine (51.8%) had a positive mpMRI using Likert score ⩾4; sensitivity was 80.6% (71.6-87.7), specificity 68.5% (60.3-75.9), NPV 83.3% (75.4-89.5) and PPV 64.3% (55.4-72.6).

Conclusions: In men advised to have a repeat prostate biopsy, prostate mpMRI could be used to safely avoid a repeat biopsy with high sensitivity for clinically significant cancers. However, such a strategy can miss some significant cancers and overdiagnose insignificant cancers depending on the mpMRI score threshold used to define which men should be biopsied.
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http://dx.doi.org/10.1038/bjc.2017.57DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5418442PMC
April 2017

Port-Site Metastases After Robotic Radical Cystectomy: A Systematic Review and Management Options.

Clin Genitourin Cancer 2017 08 29;15(4):440-444. Epub 2016 Jun 29.

Division of Surgery and Interventional Science, University College London, London, UK; Department of Urology, University College London Hospital, London, UK.

Background: Port-site metastases (PSMs) are a rare occurrence after robotic surgery. For robot-assisted radical cystectomy (RARC), isolated cases have been reported but management has not been previously described. We present a case of PSM that occurred after RARC and report the results of our systematic review of previously reported PSMs and describe the treatment options. Search Criteria and Methods: We describe a case of a PSM in a 55-year-old man who had undergone intracorporeal RARC. We performed a systematic review of MEDLINE and Embase databases for previously reported PSMs, detailing the stage and grade of the primary tumor, time to presentation of PSM, treatment offered, and outcomes for the identified cases.

Results: We identified 4 cases of PSMs after RARC in published studies and also included our case for analysis. All 5 patients had muscle-invasive bladder cancer at cystectomy (stage ≥ T2) and 3 had local lymph node-positive disease. Our aggressive treatment of chemotherapy, wide surgical excision of PSM, and radiotherapy provided our patient with a 2-year disease-free status.

Conclusion: PSMs are a rare event in RARC, with only 4 other cases reported in published studies. The outcomes have not been well reported for these cases. We propose that multimodality treatment consisting of salvage chemotherapy, surgery, and radiotherapy should be considered, although concessions could be needed after consideration of patient factors.
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http://dx.doi.org/10.1016/j.clgc.2016.06.012DOI Listing
August 2017

Partial segmental thrombosis of the corpus cavernosum presenting with perineal pain.

BMJ Case Rep 2016 Nov 22;2016. Epub 2016 Nov 22.

Department of Andrology, University College London Hospitals NHS Foundation Trust, London, UK.

We describe the case of a man aged 43 years who presented with a 2-week history of a palpable lump in the right proximal penile shaft. This was preceded by a 6-month history of perineal pain, accompanied by erectile dysfunction. An urgent MRI scan of his penis identified a thrombus within the right crus and corpus of the penis. His thrombophilia screen was normal. The patient was started on oral anticoagulation and a phosphodiesterase inhibitor (PDE-5i) to prevent thrombus progression and maintain erectile function. At 5 months, the patients' symptoms had resolved and an MRI showed a reduction in the thrombus size. MRI is a useful imaging modality to diagnose a thrombus within the corpus cavernosum in patients presenting with a history of penile and perineal pain together with a palpable lump. The non-enhancement of the lesion helps to differentiate this from alternative rare lesions within the penis and perineum.
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http://dx.doi.org/10.1136/bcr-2016-217748DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5129098PMC
November 2016

Achieving Quality Assurance of Prostate Cancer Surgery During Reorganisation of Cancer Services.

Eur Urol 2015 Jul 11;68(1):22-9. Epub 2015 Mar 11.

Department of Urology, University College Hospital London, London, UK; Division of Surgery and Interventional Science, University College London, London, UK.

Background: National Health Service England recently oversaw a whole-scale reconfiguration of cancer services in London, UK, for a number of different cancer pathways. Centralisation of cancer surgery has occurred with prostate cancer (PCa) surgery only being commissioned at a single designated pelvic cancer surgical centre. This process has required surgeons to work in teams providing a hub-and-spoke model of care.

Objective: To report the extent to which the initiation of a quality assurance programme (QAP) can improve the quality of PCa surgical care during reorganisation of cancer services in London.

Design, Setting, And Participants: A pre- and postintervention study was initiated with 732 men undergoing robot-assisted radical PCa surgery over a 3-yr period, 396 men before the introduction of the QAP and 336 afterwards.

Intervention: Image-based surgical planning of cancer surgery and monthly peer review of individual surgeon outcomes incorporating rating and assessment of edited surgical video clips.

Outcome Measurements And Statistical Analysis: We observed margin status (positive/negative), complication rate of surgery, 3-mo urinary continence, use of nerve-sparing surgery, and potency at 12 mo after surgery. Multivariable logistic regression modelling was used to compare outcomes before and after initiation of the QAP. Cox regression analysis was used to evaluate the return of potency over time.

Results And Limitations: Demographics of patients undergoing surgery did not change following the reorganisation of cancer services. Patient-reported 3-mo urinary continence improved following the initiation of the QAP, both in terms of requirement for incontinence pads (57% continent vs 67% continent; odds ratio [OR]: 2.19; 95% confidence interval [CI], 1.08-4.46; p=0.02) and International Consultation on Incontinence Questionnaire score (5.6 vs 4.2; OR: 0.82; 95% CI, 0.70-0.95; p=0.009). Concurrently, use of nerve-sparing surgery increased significantly (OR: 2.99; 95% CI, 2.14-4.20; p<0.001) while margin status remained static. Potency at 12 mo increased significantly from 21% to 61% in those patients undergoing bilateral nerve-sparing surgery (hazard ratio: 3.58; 95% CI, 1.29-9.87; p=0.04). Interaction was noted between surgeon and 3-mo urinary continence. On regression analysis, incontinence scores improved significantly for all but one surgeon who had low incontinence rates at study initiation.

Conclusions: The implementation of a QAP improved quality of care in terms of consistency of patient selection and outcomes of surgery during a period of major reorganisation of cancer services in London. The QAP framework presented could be adopted by other organisations providing complex surgical care across a large network of referring hospitals.

Patient Summary: The introduction of a quality assurance programme improved the quality of prostate cancer care in terms of consistency of patient selection and outcomes of surgery during a period of major reorganisation of cancer services.
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http://dx.doi.org/10.1016/j.eururo.2015.02.028DOI Listing
July 2015

High-resolution diffusion tensor imaging of the human kidneys using a free-breathing, multi-slice, targeted field of view approach.

NMR Biomed 2014 Nov 15;27(11):1300-12. Epub 2014 Sep 15.

Centre for Medical Imaging, University College London, London, UK.

Fractional anisotropy (FA) obtained by diffusion tensor imaging (DTI) can be used to image the kidneys without any contrast media. FA of the medulla has been shown to correlate with kidney function. It is expected that higher spatial resolution would improve the depiction of small structures within the kidney. However, the achievement of high spatial resolution in renal DTI remains challenging as a result of respiratory motion and susceptibility to diffusion imaging artefacts. In this study, a targeted field of view (TFOV) method was used to obtain high-resolution FA maps and colour-coded diffusion tensor orientations, together with measures of the medullary and cortical FA, in 12 healthy subjects. Subjects were scanned with two implementations (dual and single kidney) of a TFOV DTI method. DTI scans were performed during free breathing with a navigator-triggered sequence. Results showed high consistency in the greyscale FA, colour-coded FA and diffusion tensors across subjects and between dual- and single-kidney scans, which have in-plane voxel sizes of 2 × 2 mm(2) and 1.2 × 1.2 mm(2) , respectively. The ability to acquire multiple contiguous slices allowed the medulla and cortical FA to be quantified over the entire kidney volume. The mean medulla and cortical FA values were 0.38 ± 0.017 and 0.21 ± 0.019, respectively, for the dual-kidney scan, and 0.35 ± 0.032 and 0.20 ± 0.014, respectively, for the single-kidney scan. The mean FA between the medulla and cortex was significantly different (p < 0.001) for both dual- and single-kidney implementations. High-spatial-resolution DTI shows promise for improving the characterization and non-invasive assessment of kidney function.
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http://dx.doi.org/10.1002/nbm.3190DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4265306PMC
November 2014

A prospective development study investigating focal irreversible electroporation in men with localised prostate cancer: Nanoknife Electroporation Ablation Trial (NEAT).

Contemp Clin Trials 2014 Sep 26;39(1):57-65. Epub 2014 Jul 26.

Division of Surgery and Interventional Science, University College London, London, UK; Department of Urology, University College London Hospitals NHS Foundation Trust, London, UK.

Introduction: Focal therapy may reduce the toxicity of current radical treatments while maintaining the oncological benefit. Irreversible electroporation (IRE) has been proposed to be tissue selective and so might have favourable characteristics compared to the currently used prostate ablative technologies. The aim of this trial is to determine the adverse events, genito-urinary side effects and early histological outcomes of focal IRE in men with localised prostate cancer.

Methods: This is a single centre prospective development (stage 2a) study following the IDEAL recommendations for evaluating new surgical procedures. Twenty men who have MRI-visible disease localised in the anterior part of the prostate will be recruited. The sample size permits a precision estimate around key functional outcomes. Inclusion criteria include PSA ≤ 15 ng/ml, Gleason score ≤ 4 + 3, stage T2N0M0 and absence of clinically significant disease outside the treatment area. Treatment delivery will be changed in an adaptive iterative manner so as to allow optimisation of the IRE protocol. After focal IRE, men will be followed during 12 months using validated patient reported outcome measures (IPSS, IIEF-15, UCLA-EPIC, EQ-5D, FACT-P, MAX-PC). Early disease control will be evaluated by mpMRI and targeted transperineal biopsy of the treated area at 6 months.

Discussion: The NEAT trial will assess the early functional and disease control outcome of focal IRE using an adaptive design. Our protocol can provide guidance for designing an adaptive trial to assess new surgical technologies in the challenging landscape of health technology assessment in prostate cancer treatment.
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http://dx.doi.org/10.1016/j.cct.2014.07.006DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4189798PMC
September 2014

Synchronous renal masses in patients with a nonrenal malignancy: incidence of metastasis to the kidney versus primary renal neoplasia and differentiating features on CT.

AJR Am J Roentgenol 2011 Oct;197(4):W680-6

Department of Radiology, St. George's Hospital and Medical School, Blackshaw Rd, London SW17 0QT, United Kingdom.

Objective: The purpose of this study was to establish the contemporaneous frequency of metastases within the kidney as opposed to primary renal tumors in patients with an active primary nonrenal malignancy and to identify the differentiating features.

Materials And Methods: We retrospectively identified all patients with an active primary nonrenal malignancy (group 1) who had also undergone at least 2 contrast-enhanced abdominal CT examinations spaced 1 year apart. The radiologic and pathologic data of these cases were reviewed and the incidence of metastasis to the kidney versus primary renal tumors established. These data were compared with a separate group who presented with primary renal malignancy from the outset (group 2).

Results: In the study were 2340 patients with primary nonrenal malignancy (group 1) and 231 patients with a primary renal malignancy (group 2). For group 1, the mean age was 63 years and 51% were men; for group 2, the mean age was 59 years, and 58% were men. The differences were not statistically significant. Thirty-six patients in group 1 had a malignant renal mass; 21 were a result of kidney metastasis and the remaining 15 were a synchronous primary renal tumor (0.9% vs 0.6%). The kidney was the eighth most common site of metastatic spread. Metastases to the kidney were statistically more likely with higher tumor stage of the primary nonrenal malignancy (68% vs 46%, p = 0.0006) and in those with other sites of metastasis (p = 0.012, positive likelihood ratio [LR+] = 6.75). Compared with primary renal tumors, metastases to the kidney were more often solid (86% vs 53%, p = 0.019, LR+ = 3.7) and endophytic (76% vs 33%, p = 0.017, LR+ = 2.29). There were too few cases with calcification and bilateral tumors to reach a statistically significant conclusion. Tumor size, polar predominance, and enhancement pattern were similar in the two groups. The primary renal tumors seen in group 1 versus group 2 were similar regarding age and sex distribution, cell type, median size, and tumor stage.

Conclusion: Metastases to the kidney are uncommon in modern radiologic practice (0.9%, 21/2340 in this study), and a renal mass seen in a patient with nonrenal malignancy is nearly as likely to be an incidental primary renal tumor. Metastasis is more likely in those with higher tumor stage or if other viscera are also affected and is usually an asymptomatic, small, endophytic, and solid mass. If a renal mass seen in a patient with primary nonrenal malignancy proves to be a synchronous primary renal tumor, its cell type and stage will be similar to sporadic primary renal tumors.
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http://dx.doi.org/10.2214/AJR.11.6518DOI Listing
October 2011

Imaging of the airways with multidetector row computed tomography.

Paediatr Respir Rev 2008 Jun 9;9(2):69-76. Epub 2008 May 9.

Department of Imaging, Great Ormond Street Hospital for Children NHS Trust, London WC1N 3JH, UK.

The wide availability of multidetector row computed tomography (MDCT) continues to change the way we manage patients. Once the domain of the specialist paediatric centre, imaging of the paediatric thorax now routinely occurs in many general hospitals. The paediatric respiratory and radiology teams should therefore be familiar with this technique. This review examines the indications for MDCT, the different types of scan, the use of low-dose protocols for paediatric imaging and appropriate reconstruction techniques. Patient preparation, with particular respect to sedation and optimal contrast bolus delivery, is also addressed.
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http://dx.doi.org/10.1016/j.prrv.2008.01.005DOI Listing
June 2008

A cause for concern? Osteopoikilosis found incidentally in the emergency department: a case report.

Emerg Med J 2007 May;24(5):e29

Frimley Park Hospital, Frimley, Surrey, UK.

Osteopoikilosis is a rare, inherited bone disorder, which is usually found incidentally on x ray. It may be mistaken for other, more serious disorders such as bony metastases, causing undue distress to the doctor and patient.
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http://dx.doi.org/10.1136/emj.2006.045765DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2658513PMC
May 2007
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