Unusual Radiotracer Deposition to the Forearm After Intrahepatic Injection of 99mTc-Macroaggregated Albumin Using a Transradial Approach.

ABSTRACT: Arterial mapping and 99mTc-macroaggregated albumin (99mTc-MAA) hepatic perfusion imaging are routinely performed before 90Y radioembolization of hepatic tumors. These procedures serve multiple purposes, including an anatomical survey of hepatic arterial anatomy, interrogating expected microsphere distribution to avoid nontargeted embolization during therapy, and evaluating for possible hepatopulmonary shunting. We present a case where 99mTc-MAA planar images revealed unexpected soft tissue uptake within the left forearm, an unexpected complication that may result from residual 99mTc-MAA in the catheter being expelled as the catheter is removed, which is particularly important to avoid during the 90Y radioembolization procedure given the risk for associated radionecrosis.

Extracellular Matrix Scaffold Technology for Bioartificial Pancreas Engineering: State of the Art and Future Challenges.

Emergent technologies in regenerative medicine may soon overcome the limitations of conventional diabetes therapies. Collaborative efforts across the subfields of stem cell technology, islet encapsulation, and biomaterial carriers seek to produce a bioengineered pancreas capable of restoring endocrine function in patients with insulin-dependent diabetes. These technologies rely on a robust understanding of the extracellular matrix (ECM), the supportive 3-dimensional network of proteins necessary for cellular attachment, proliferation, and differentiation. Although these functions can be partially approximated by biosynthetic carriers, novel decellularization protocols have allowed researchers to discover the advantages afforded by the native pancreatic ECM. The native ECM has proven to be an optimal platform for recellularization and whole-organ pancreas bioengineering, an exciting new field with the potential to resolve the dire shortage of transplantable organs. This review seeks to contextualize recent findings, discuss current research goals, and identify future challenges of regenerative medicine as it applies to diabetes management.

Impact of immunosuppression minimization and withdrawal in long-term hepatitis C virus liver transplant recipients.

AIM: To investigate the effects of different immunosuppressive regimens and avoidance on fibrosis progression in hepatitis C virus (HCV) liver transplant (LT) recipients. METHODS: We retrospectively compared the liver biopsies of well-matched HCV LT recipients under calcineurin inhibitors (CNI group, n = 21) and mycophenolate (MMF group, n = 15) monotherapy, with those patients who successfully withdrawn immunosuppression (IS) therapy from at least 3 years (TOL group, n = 10). To perform the well-matched analysis, all HCV transplanted patients from December 1993 were screened. Only those HCV patients who reached the following criteria were considered for the analysis: (1) at least 3 years of post-operative follow-up; (2) patients with normal liver graft function under low dose CNI monotherapy (CNI group); (3) patients with normal liver graft function under antimetabolite (Micophenolate Mofetil or coated mycophenolate sodium) monotherapy (MMF group); and (4) recipients with normal liver function without any IS. We excluded from the analysis recipients who were IS free or under monotherapy for < 36 mo, recipients with cirrhosis or with unstable liver function tests. RESULTS: Thirty six recipients were enrolled in the study. Demographics, clinical data, time after LT and baseline liver biopsies were comparable in the three groups. After six years of follow-up, there was no worsening of hepatic fibrosis in the MMF group (2.5 ± 1.5 Ishak Units vs 2.9 ± 1.7 Ishak Units, P = 0.5) and TOL group (2.7 ± 10.7 vs 2.5 ± 1.2, P = 0.2). In contrast, a significant increase in the fibrosis score was observed in the CNI group (2.2 ± 1.7 vs 3.9 ± 1.6, P = 0.008). The yearly fibrosis progression rate was significantly worse in the CNI group (0.32 ± 0.35) vs MMF group (0.03 ± 0.31, P = 0.03), and TOL group (-0.02 ± 0.27, P = 0.02). No differences have been reported in grading scores for CNI group (2.79 ± 1.9, P = 0.7), MMF group (3.2 ± 1.5, P = 0.9) and TOL group (3.1 ± 1.4, P = 0.2). Twenty four patients were treated with low dose ribavirin (8 TOL, 7 MMF, 9 CNI). The hepatitis C titers were comparable in the three groups. No episodes of rejection have been reported despite differences of liver function test in the three groups during the observational period. CONCLUSION: IS withdrawal and MMF monotherapy is safe and seems to be associated with the slowest fibrosis progression in HCV LT recipients.