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Background: Hepatic cyst disease is often asymptomatic, but treatment is warranted if patients experience symptoms. We describe our management approach to these patients and review the technical nuances of the laparoscopic approach. Methods: Medical records were reviewed for operative management of hepatic cysts from 2012 to 2019 at a single, tertiary academic medical center. Results: Fifty-three patients (39 female) met the inclusion criteria with median age at presentation of 65 years. Fifty cases (94.3%) were performed laparoscopically. Fourteen patients carried diagnosis of polycystic liver disease. Dominant cyst diameter was median 129 mm and located within the right lobe (30), left lobe (17), caudate (2), or was bilobar (4). Pre-operative concern for biliary cystadenoma/cystadenocarcinoma existed for 7 patients. Operative techniques included fenestration (40), fenestration with decapitation (7), decapitation alone (3), and excision (2). Partial hepatectomy was performed in conjunction with fenestration/decapitation for 15 cases: right sided (7), left sided (7), and central (1). One formal left hepatectomy was performed in a polycystic liver disease patient. Final pathology yielded simple cyst (52) and one biliary cystadenoma. Post-operative complications included bile leak (2), perihepatic fluid collection (1), pleural effusion (1), and ascites (1). At median 7.1-month follow-up, complete resolution of symptoms occurred for 34/49 patients (69.4%) who had symptoms preoperatively. Reintervention for cyst recurrence occurred for 5 cases (9.4%). Conclusions: Outcomes for hepatic cyst disease are described with predominantly laparoscopic approach, approach with minimal morbidity, and excellent clinical results.

Islet transplantation offers a minimally invasive approach for β cell replacement in diabetic patients with hypoglycemic unawareness. Attempts at insulin independence may require multiple islet reinfusions from distinct donors, increasing the risk of allogeneic sensitization. Currently, solid organ pancreas transplant is the only remaining surgical option following failed islet transplantation in the United States; however, the immunologic impact of repeated exposure to donor antigens on subsequent pancreas transplantation is unclear. We describe a case series of seven patients undergoing solid organ pancreas transplant following islet graft failure with long-term follow-up of pancreatic graft survival and renal function. Despite highly variable panel reactive antibody levels prior to pancreas transplant (mean 27 ± 35%), all seven patients achieved stable and durable insulin independence with a mean follow-up of 6.7 years. Mean hemoglobin A1c values improved significantly from postislet, prepancreas levels (mean 8.1 ± 1.5%) to postpancreas levels (mean 5.3 ± 0.1%; p = 0.0022). Three patients experienced acute rejection episodes that were successfully managed with thymoglobulin and methylprednisolone, and none of these preuremic type 1 diabetic recipients developed stage 4 or 5 chronic kidney disease postoperatively. These results support pancreas-after-islet transplantation with aggressive immunosuppression and protocol biopsies as a viable strategy to restore insulin independence after islet graft failure.

A special type of 7 T 240 mm vertical bore cryogen-free superconducting magnet system is developed that can be used for gyrotron. This magnet system has contributed to the fast control of the gyrotron oscillation frequency.

A superconducting magnet of small size and easy operation was developed for generating high magnetic force field. Results suggest the successful operation of the magnet in persistent mode with field decay of less than 1 ppm/h.

A numerical quench simulation code was modified to take into account the impact of filament coupling loss when computing the temperature rise in multisection superconducting coils. The new program, which has been applied to a 17.6-T and a17-T magnet, shows good agreement with experimental results. This is important because the filament coupling loss increases the temperature which, in turn, decreases the critical current in the coil.

A simulation code for worst-case parameter estimation of the quench properties in multisection superconducting coils is introduced. It is a design tool in the joint project between the Massachusetts Institute of Technology and Japan's Kobe Steel Ltd for the development of a 12-coil 17.6-T 750-MHz nuclear magnetic resonance system. Its application for testing the magnet's five outer niobium titanium solenoids are also discussed.

A superconducting magnet generating a magnetic force field of 1500 T(super 2)/ m in a 40 mm diameter room temperature bore is developed. In order to avoid huge axial magnetic forces between the main coils and the reverse coils, the main coils are combined with three sections set asymmetrically.