A Ten-Year Kuala Lumpur Review on Laser Posterior Cordectomy for Bilateral Vocal Fold Immobility

Bilateral vocal fold immobility (BVFI) is commonly caused by injury to the recurrent laryngeal nerve (RLN) and leads to stridor and dyspnea of varying onsets. A retrospective study was done at the Department of Otorhinolaryngology of Universiti Kebangsaan Malaysia Medical Centre on laser microsurgical posterior cordectomy for BVFI. The objectives were to identify the average duration of onset of stridor from the time of insult and to evaluate the outcome of laser posterior cordectomy as a surgical option. From 1997 to 2007, a total of 31 patients with BVFI were referred for surgery. Twelve patients had tracheostomy done prior to the procedure, whereas 19 patients were without tracheostomy. Ten patients were successfully decannulated, and only 4 patients had complications related to the procedure. The minimum onset of stridor was 7 months, maximum onset of stridor was 28 years, and the mean onset of stridor was 8.7 years. The commonest complication observed was posterior glottic adhesion following bilateral posterior cordectomy. Laser endolaryngeal posterior cordectomy is an excellent surgical option as it enables successful decannulation or avoidance of tracheostomy in patients with BVFI. The onset of stridor took years after the insult to the recurrent laryngeal nerves.

Irreversible electroporation technology for ablation treatment of tumors：recent progress in research / 介入放射学杂志

Irreversible electroporation, known as nano-knife, is a newly-developed technology, which can effectively ablate tumor tissues. This technology uses electric pulse to permanently destroy the double phospholipid layer of the cell membrane in the target area, resulting in tumor cell death. Its tumor ablation effect has already been confirmed in animal experiment as well as in clinical study. As this technology has no thermal effect, the adjacent connective tissue matrix such as blood vessels, nerves and biliary ducts will not be damaged. This article aims to make a brief review about its technical principle and apparatus, and its advantages, disadvantages as well as the recent progress in clinical research will also be discussed.

Atrophy of brown adipocytes in the adult mouse causes transformation into white adipocyte-like cells

Adipose tissue is an important endocrine regulator of glucose metabolism and energy homeostasis. Researches have focused on this tissue not only as a target for pharmacotherapy of obesity and insulin resistance but also as an endocrine tissue with leptin secretion and high insulin sensitivity. Brown adipose tissue (BAT) additionally plays a unique role in thermoregulation through the mitochondrial uncoupling protein 1 (UCP1), which uncouples oxidative phosphorylation. As a genetic tissue ablation model of BAT, we made transgenic mice expressing herpes simplex virus thymidine kinase (HSV-TK) driven by the brown adipocyte- specific UCP1 minimal regulatory element. The HSV-TK transgene was expressed specifically in BAT and more than 35% increase of apoptosis was induced by ganciclovir (GCV) treatment. Nevertheless, the expression level was not high enough to induce BAT ablation in GCV-treated adult mice. Importantly, however, we found that brown adipocytes in the periphery of interscapular BAT were transformed into white adipocyte-like unilocular cells. These cells express white adipocyte-specific leptin protein but are different in the ultrastructure of mitochondria from classical white adipocytes. Our data indicates that atrophy of BAT causes transformation into white adipocyte-like cells in the adult mouse and also suggests that further molecular understanding of adipocyte plasticity using our transgenic mouse model might be beneficial for the development of anti-obesity/anti-diabetic therapies.

Saline-Enhanced Radiofrequency Thermal Ablation of the Lung: A Feasibility Study in Rabbits

OBJECTIVE: To assess the feasibility and safety of CT-guided percutaneous transthoracic radiofrequency ablation (RFA) with saline infusion of pulmonary tissue in rabbits. MATERIALS AND METHODS: Twenty-eight New Zealand White rabbits were divided into two groups: an RFA group (n=10) and a saline-enhanced RFA (SRFA) group (n=18). In the RFA group, percutaneous RFA of the lung was performed under CT guidance and using a 17-gauge internally cooled electrode. In the SRFA group, 1.5 ml of 0.9% saline was infused slowly through a 21-gauge, polyteflon-coated Chiba needle prior to and during RFA. Lesion size and the healing process were studied in rabbits sacrificed at times from the day following treatment to three weeks after, and any complications were noted. RESULTS: In the SRFA group, the mean diameter (12.5+/-1.6 mm) of acute RF lesions was greater than that of RFA lesions (8.5+/-1.4 mm) (p < .05). The complications arising in 12 cases were pneumothorax (n=8), thermal injury to the chest wall (n=2), hemothorax (n=1), and lung abscess (n=1). Although procedure-related complications tended to occur more frequently in the SRFA group (55.6%) than in the RFA group (20%), the difference was not statistically significant (p = .11). CONCLUSION: Saline-enhanced RFA of pulmonary tissue in rabbits produces more extensive coagulation necrosis than conventional RFA procedures, without adding substantial risk of serious complications.