Adolescent male with bilateral succinate dehydrogenase-deficient renal cell carcinoma in a horseshoe kidney managed successfully with staged bilateral robotic-assisted partial nephrectomies: A case report.

Succinate dehydrogenase (SDH) deficient renal cell carcinoma (RCC) is a rare subset of familial RCC with only 59 cases reported. SDH deficiency is associated with hereditary paraganglioma/pheochromocytoma syndrome. Most of the cases are solitary tumors with only two reported cases of bilateral tumor. The identification of SDH deficient RCC is often the sentinel event of patient's syndromic diagnosis. We present a case of an adolescent male with bilateral tumors in a horseshoe kidney who was treated with staged robotic-assisted partial nephrectomies without complication. Both tumors were SDH negative on immunohistochemical staining.

Robotic-assisted nephrectomy with level II IVC thrombectomy using Rummel Tourniquets

ABSTRACT Background: Inferior vena cava (IVC) invasion from renal cell carcinoma (RCC) occurs at a rate of 4-10% (1). IVC thrombectomy (IVC-TE) can be an open procedure because of the need for handling of the IVC (2). The first reported series of robotic management of IVC-TE started in 2011 for the management of Level I - II thrombi with subsequent case reports in recent years (2-5). Materials and Methods: The following is a patient in his 50's with no significant medical history. Magnetic resonance imaging and IR venogram were performed preoperatively. The tumor was clinical stage T3b with a 4.3cm inferior vena cava thrombus. The patient underwent robotic assisted nephrectomy and IVC-TE. Rummel tourniquets were used for the contralateral kidney and the IVC. The tourniquets were created using vessel loops, a 24 French foley catheter and hem-o-lock clips. Results: The patient tolerated the surgical procedure well with no intraoperative complications. Total surgical time was 274 min with 200 minutes of console time and 22 minutes of IVC occlusion. Total blood loss in the surgery was 850cc. The patient was discharged from the hospital on post-operative day 3 without any complications. The final pathology of the specimen was pT3b clear cell renal cell carcinoma Fuhrman grade 2. The patient followed up post-operatively at both four months and six months without disease recurrence. The patient continues annual follow-up with no recurrence. Conclusions: Surgeon experience is a key factor in radical nephrectomy with thrombectomy as patients have a reported 50-65% survival rate after IVC-TE (4).

How we do it: robotic-assisted distal ureterectomy with ureteral reimplantation

ABSTRACT Background: High risk upper tract urothelial carcinoma (UTUC) is typically managed with radical nephroureterectomy, however, renal preservation can be attempted when UTUC is localized to the distal ureter in the presence of chronic kidney disease (1-3). Distal ureterectomy is typically managed with a ureteral reimplantation and psoas hitch in order to maintain urothelial continuity, to avoid comprising the contralateral ureter, and reducing risk of chronic urinary tract infections and electrolyte abnormalities (4). We present our case of distal ureteral UTUC managed robotically with a distal ureterectomy with ureteral reimplantation. Technique and Follow-Up: Initially, an Orandi needle on a resectoscope circumscribed the left ureteral orifice. Next, robotically, the retroperitoneum was exposed and a left sided pelvic lymphadenectomy was completed. The left ureter was mobilized and the diseased ureteral segment was transected. The mobilized bladder was sutured to psoas fascia. After a cystotomy, the ureter was re-anastomosed to the bladder. The patient was discharged on postoperative day three and re-evaluated one week later with a cystogram. Final pathology was downgraded to non-invasive low-grade papillary urothelial carcinoma with negative lymph nodes and margins. Conclusion: High risk UTUC localized to the distal ureter in the setting of chronic kidney disease can be managed with a distal ureterectomy (3). Robotic distal ureterectomy with ureteral reimplantation can be assisted by an Orandi needle to achieve negative margins. Utilizing a robotic technique can offer challenges with the ureteral spatulation and reanastomosis (5-7). By fixating the ureter to the bladder prior to reanastomosis, our technique offers a solution for these difficulties.

T1 mapping performance and measurement repeatability: results from the multi-national T1 mapping standardization phantom program (T1MES).

BACKGROUND: The T1 Mapping and Extracellular volume (ECV) Standardization (T1MES) program explored T1 mapping quality assurance using a purpose-developed phantom with Food and Drug Administration (FDA) and Conformité Européenne (CE) regulatory clearance. We report T1 measurement repeatability across centers describing sequence, magnet, and vendor performance. METHODS: Phantoms batch-manufactured in August 2015 underwent 2 years of structural imaging, B0 and B1, and "reference" slow T1 testing. Temperature dependency was evaluated by the United States National Institute of Standards and Technology and by the German Physikalisch-Technische Bundesanstalt. Center-specific T1 mapping repeatability (maximum one scan per week to minimum one per quarter year) was assessed over mean 358 (maximum 1161) days on 34 1.5 T and 22 3 T magnets using multiple T1 mapping sequences. Image and temperature data were analyzed semi-automatically. Repeatability of serial T1 was evaluated in terms of coefficient of variation (CoV), and linear mixed models were constructed to study the interplay of some of the known sources of T1 variation. RESULTS: Over 2 years, phantom gel integrity remained intact (no rips/tears), B0 and B1 homogenous, and "reference" T1 stable compared to baseline (% change at 1.5 T, 1.95 ± 1.39%; 3 T, 2.22 ± 1.44%). Per degrees Celsius, 1.5 T, T1 (MOLLI 5s(3s)3s) increased by 11.4 ms in long native blood tubes and decreased by 1.2 ms in short post-contrast myocardium tubes. Agreement of estimated T1 times with "reference" T1 was similar across Siemens and Philips CMR systems at both field strengths (adjusted R2 ranges for both field strengths, 0.99-1.00). Over 1 year, many 1.5 T and 3 T sequences/magnets were repeatable with mean CoVs < 1 and 2% respectively. Repeatability was narrower for 1.5 T over 3 T. Within T1MES repeatability for native T1 was narrow for several sequences, for example, at 1.5 T, Siemens MOLLI 5s(3s)3s prototype number 448B (mean CoV = 0.27%) and Philips modified Look-Locker inversion recovery (MOLLI) 3s(3s)5s (CoV 0.54%), and at 3 T, Philips MOLLI 3b(3s)5b (CoV 0.33%) and Siemens shortened MOLLI (ShMOLLI) prototype 780C (CoV 0.69%). After adjusting for temperature and field strength, it was found that the T1 mapping sequence and scanner software version (both P < 0.001 at 1.5 T and 3 T), and to a lesser extent the scanner model (P = 0.011, 1.5 T only), had the greatest influence on T1 across multiple centers. CONCLUSION: The T1MES CE/FDA approved phantom is a robust quality assurance device. In a multi-center setting, T1 mapping had performance differences between field strengths, sequences, scanner software versions, and manufacturers. However, several specific combinations of field strength, sequence, and scanner are highly repeatable, and thus, have potential to provide standardized assessment of T1 times for clinical use, although temperature correction is required for native T1 tubes at least.

A medical device-grade T1 and ECV phantom for global T1 mapping quality assurance-the T1 Mapping and ECV Standardization in cardiovascular magnetic resonance (T1MES) program.

BACKGROUND: T1 mapping and extracellular volume (ECV) have the potential to guide patient care and serve as surrogate end-points in clinical trials, but measurements differ between cardiovascular magnetic resonance (CMR) scanners and pulse sequences. To help deliver T1 mapping to global clinical care, we developed a phantom-based quality assurance (QA) system for verification of measurement stability over time at individual sites, with further aims of generalization of results across sites, vendor systems, software versions and imaging sequences. We thus created T1MES: The T1 Mapping and ECV Standardization Program. METHODS: A design collaboration consisting of a specialist MRI small-medium enterprise, clinicians, physicists and national metrology institutes was formed. A phantom was designed covering clinically relevant ranges of T1 and T2 in blood and myocardium, pre and post-contrast, for 1.5 T and 3 T. Reproducible mass manufacture was established. The device received regulatory clearance by the Food and Drug Administration (FDA) and Conformité Européene (CE) marking. RESULTS: The T1MES phantom is an agarose gel-based phantom using nickel chloride as the paramagnetic relaxation modifier. It was reproducibly specified and mass-produced with a rigorously repeatable process. Each phantom contains nine differently-doped agarose gel tubes embedded in a gel/beads matrix. Phantoms were free of air bubbles and susceptibility artifacts at both field strengths and T1 maps were free from off-resonance artifacts. The incorporation of high-density polyethylene beads in the main gel fill was effective at flattening the B 1 field. T1 and T2 values measured in T1MES showed coefficients of variation of 1 % or less between repeat scans indicating good short-term reproducibility. Temperature dependency experiments confirmed that over the range 15-30 °C the short-T1 tubes were more stable with temperature than the long-T1 tubes. A batch of 69 phantoms was mass-produced with random sampling of ten of these showing coefficients of variations for T1 of 0.64 ± 0.45 % and 0.49 ± 0.34 % at 1.5 T and 3 T respectively. CONCLUSION: The T1MES program has developed a T1 mapping phantom to CE/FDA manufacturing standards. An initial 69 phantoms with a multi-vendor user manual are now being scanned fortnightly in centers worldwide. Future results will explore T1 mapping sequences, platform performance, stability and the potential for standardization.