ABSTRACT
Cancer-associated vein obstruction (CAVO) is a common complication in oncological patients, but the effective therapeutic options are scant. We report a patient with reiterative recurrent CAVO who was successfully treated with intraluminal brachytherapy using a self-expandable stent loaded with linear radioactive iodine-125 seeds (RIS) strand. During follow-up, her clinical symptoms were well improved. Three-month imaging follow-up revealed satisfactory patency of the iliofemoral vein, and the stents combined with RIS strands performed well. No serious complications associated with the implantation of stent and RIS strands were documented in any of the sessions. Intraluminal brachytherapy using a self-expandable stent loaded with linear RIS may be a safe and effective option for CAVO as long as it includes not only blood flow restoration but also brachytherapy administration for cancer.
Subject(s)
Brachytherapy/instrumentation , Endovascular Procedures/instrumentation , Femoral Vein/radiation effects , Iliac Vein/radiation effects , Iodine Radioisotopes/administration & dosage , Neoplastic Cells, Circulating/radiation effects , Rectal Neoplasms/radiotherapy , Stents , Vascular Diseases/radiotherapy , Aged , Computed Tomography Angiography , Constriction, Pathologic , Female , Femoral Vein/diagnostic imaging , Femoral Vein/pathology , Humans , Iliac Vein/diagnostic imaging , Iliac Vein/pathology , Neoplastic Cells, Circulating/pathology , Phlebography/methods , Radiography, Interventional , Rectal Neoplasms/complications , Rectal Neoplasms/pathology , Recurrence , Treatment Outcome , Vascular Diseases/diagnostic imaging , Vascular Diseases/etiology , Vascular Diseases/pathology , Vascular PatencyABSTRACT
BACKGROUND: Based on growing evidence that some adult multipotent cells necessary for tissue regeneration reside in the walls of blood vessels and the clinical success of vein wrapping for functional repair of nerve damage, we hypothesized that the repair of nerves via vein wrapping is mediated by cells migrating from the implanted venous grafts into the nerve bundle. METHODOLOGY/PRINCIPAL FINDINGS: To test the hypothesis, severed femoral nerves of rats were grafted with venous grafts from animals of the opposite sex. Nerve regeneration was impaired when decellularized or irradiated venous grafts were used in comparison to untreated grafts, supporting the involvement of venous graft-derived cells in peripheral nerve repair. Donor cells bearing Y chromosomes integrated into the area of the host injured nerve and participated in remyelination and nerve regeneration. The regenerated nerve exhibited proper axonal myelination, and expressed neuronal and glial cell markers. CONCLUSIONS/SIGNIFICANCE: These novel findings identify the mechanism by which vein wrapping promotes nerve regeneration.
Subject(s)
Femoral Nerve/physiopathology , Femoral Nerve/surgery , Femoral Vein/transplantation , Nerve Regeneration , Animals , Axons/metabolism , Axons/ultrastructure , Cell Movement , Cell Proliferation , Cells, Cultured , Female , Femoral Nerve/injuries , Femoral Vein/cytology , Femoral Vein/radiation effects , Immunohistochemistry , In Situ Hybridization, Fluorescence , Male , Microscopy, Electron, Transmission , Nerve Fibers, Myelinated/metabolism , Nerve Fibers, Myelinated/ultrastructure , Neurofilament Proteins/metabolism , Rats , Rats, Inbred F344 , Schwann Cells/metabolism , Schwann Cells/ultrastructure , Sex Factors , Transplantation, HomologousABSTRACT
OBJECTIVE: The graft patency rate after coronary artery bypass grafting (CABG) correlates with anastomotic stenosis. Intracoronary radiation therapy is effective for preventing restenosis after percutaneous coronary intervention (PCI). We postulated that intracoronary radiation therapy could prevent anastomotic stenosis and tested this hypothesis in an animal model. METHODS: Femoral arteries and veins of beagle dogs were harvested, and composite arterioarterial and arteriovenous grafts were prepared. After external irradiation of the anastomotic sites, these composite grafts were transplanted into femoral arteries. Histomorphometric and immunohistological analyses of the anastomotic sites were performed. The study groups consisted of controls and animals exposed to 10 Gy, 20 Gy, and 30 Gy (n = 5, in each group). RESULTS: In the artery graft model, the ratio of negative remodeling was significantly increased in all groups exposed to >or=10 Gy. The ratio of neointimal hyperplasia was significantly decreased in all groups exposed to >or=10 Gy. Cell density of anti-alpha-actin antibody-positive cells and anti-proliferating cell nuclear antigen (PCNA) antibody-positive cells was highest in the adventitial layer, and the density decreased as the dosage increased. Experimental results were almost the same in the vein graft models as in the artery graft models. With double immunohistostaining, the anti-PCNA antibody-positive cells expressed alpha-actin. CONCLUSION: Irradiation can inhibit anastomotic stenosis in a canine model. Adventitia is a factor in the creation of stenosis, and irradiation appears to target the adventitia. We speculate that there might be a possible role for intracoronary irradiation in the future to prevent anastomotic stenosis.
Subject(s)
Arteriovenous Shunt, Surgical/adverse effects , Femoral Artery/radiation effects , Femoral Vein/radiation effects , Graft Occlusion, Vascular/prevention & control , Tunica Intima/radiation effects , Actins/metabolism , Animals , Cell Proliferation/radiation effects , Constriction, Pathologic , Dogs , Femoral Artery/metabolism , Femoral Artery/pathology , Femoral Artery/surgery , Femoral Vein/metabolism , Femoral Vein/pathology , Femoral Vein/surgery , Graft Occlusion, Vascular/etiology , Graft Occlusion, Vascular/metabolism , Graft Occlusion, Vascular/pathology , Hyperplasia , Models, Animal , Proliferating Cell Nuclear Antigen/metabolism , Radiation Dosage , Tunica Intima/metabolism , Tunica Intima/pathology , Tunica Intima/surgeryABSTRACT
Arterial occlusive disease is a well-known complication of radiation therapy, but venous thrombosis and occlusion after radiotherapy may also occur. We report the use of an endovascular stent to treat a patient who developed peripheral venous stenosis 4 years after radiation therapy for malignant melanoma.
Subject(s)
Arterial Occlusive Diseases/therapy , Peripheral Vascular Diseases/therapy , Radiotherapy/adverse effects , Stents , Arterial Occlusive Diseases/diagnostic imaging , Arterial Occlusive Diseases/etiology , Femoral Vein/radiation effects , Humans , Male , Melanoma/radiotherapy , Middle Aged , Peripheral Vascular Diseases/diagnostic imaging , Peripheral Vascular Diseases/etiology , Radiography, Interventional , Skin Neoplasms/radiotherapyABSTRACT
The influence of radiation on microvascular anastomoses were investigated on the femoral artery and vein of the rat. In an increasing number of operations free transplantations after tumor resections of the head and neck are performed. In advanced tumors postoperative radiation would be desired as early as possible. The histological changes and the patency of the vessels were investigated. The results indicate that an immediate postoperative radiation is possible even after an free microvascular transplantation.
Subject(s)
Femoral Artery/surgery , Femoral Vein/surgery , Microcirculation/surgery , Animals , Femoral Artery/pathology , Femoral Artery/radiation effects , Femoral Vein/pathology , Femoral Vein/radiation effects , Microcirculation/pathology , Microcirculation/radiation effects , Rats , Rats, Inbred StrainsABSTRACT
Autogenous veins are the ideal substitute for bridging venous defects. Experimentally, fresh homografts have patency rates comparable to autografts. However, a method of preservation must be employed if homografts become practical for clinical use. In this study, homografts were frozen, irradiated, and stored for a total of 6 weeks. Following femoral venous reconstruction, patency rates between frozen, irradiated homografts and fresh autografts were compared and found to be similar over a 6 month period. Recanalization of the frozen, irradiated homografts occurred at the same rate as did that of the autografts. This study concludes that cryopreservation and irradiation are suitable methods of preservation that do not adversely affect patency. In addition irradiation will sterilize tissue and may decrease the potential of the graft to stimulate the recipient's immunologic system.
