Efficacy of radical neck dissection for the control of cervical metastasis after radiotherapy for nasopharyngeal carcinoma

Fifty-one patients who had persistent or recurrent neck disease from nasopharyngeal carcinoma after radiotherapy underwent radical neck dissection. The follow-up period ranged from 0.5 to 9 years (median: 2 years). Multiple cervical lymph node involvement was present in 51% of the patients (26 of 51). Malignant cells were detected in 88% of the resected specimens (45 of 51). The clinical sign of fixation of lymph node is the only factor that affects the successful control of neck disease (p = 0.04). Extracapsular extension of the nodal disease was present, and 35% of the lymph nodes were adherent to surrounding structures at operation (18 of 51). There was one hospital mortality and the overall morbidity was minimal. The actuarial survival at 5 years was 38%, and the probability of control of neck disease was 66%. Radical neck dissection is effective in controlling post-irradiation cervical metastasis from nasopharyngeal carcinoma.     

Effect of Yag-laser anterior capsulotomy on the biochemical content of aqueous humor

Elevation of prostaglandins and protein in the aqueous humor is an immediate response to Yag-laser anterior capsulotomy. There was a significant correlation between prostaglandins and thromboxane to the elevation of intraocular pressure. The elevation of protein concentration was proportional to the elevation of prostaglandin F1, but not to thromboxane. The biochemical changes in the aqueous humor were more severe as laser power was increased above 3 mj. While the role of prostaglandins in the elevation of intraocular pressure is uncertain, the present data recommend the selection of laser power below 3 mj to avoid pressure rise instead of inhibition of all prostaglandin synthesis by medication.     

Comparison of near heterophoria tests under varying conditions on an adult sample

PURPOSE: This study compared the near phoria measurement using the Bernell muscle balance card with and without prism neutralization, using both trial frame and phoropter correction, and compared with the conventional Maddox rod method. METHODS: Forty young normal Chinese adults had their near phoria measured with trial frame correction using the conventional muscle balance card method (method 1). Any deviation was compensated with a prism bar as an alternative approach (method 2). The conventional Maddox rod method (method 3) was also carried out for comparison. These three methods were repeated with phoropter correction and considered as methods 4, 5 and 6. RESULTS: The phorias obtained from these six methods were not significantly different from each other (repeated measures anova, p > 0.05). More than half of the subjects were exophoric. Although the difference in phoria was not significant, phoria measurement using phoropter correction yielded a greater coefficient of variation. CONCLUSIONS: Near phoria measurement using the muscle balance card conducted with trial frame correction was less variable, and was also more natural and similar to a real reading situation. The use of prism for compensation did not affect the phoria results. Exophoria seems to be more common than esophoria in young Chinese adults.     

Evaluation of four elastomeric interocclusal recording materials

Background: The fabrication of dental prosthesis requires the transfer of interocclusal records from patient's mouth to semiadjustable articulators using different kinds of recording media. Any inaccuracy in these interocclusal records leads to occlusal errors in the final prosthesis. This study was conducted to evaluate the dimensional changes occurring in the interocclusal recording material over a given period of time and the material's resistance to compression during the cast mounting on the articulator.     

Subarachnoid lumbar drains: A case series of fractured catheters and a near miss

PURPOSE: Lumbar subarachnoid catheters for cerebrospinal fluid (CSF) drainage (lumbar drains) are indicated for several medical and surgical conditions. A number of complications can occur from the placement of this type of catheter, including catheter breakage from excessive traction or shearing over the Tuohy needle. CLINICAL FEATURES: Five cases of lumbar subarachnoid catheter breakage/shearing and catheter fragment retention, as well as one near miss, were identified over a one-year period at a single institution. All (n = 6) patients were undergoing neurosurgical procedures. Four patients required surgical retrieval of the catheter fragments. No patient experienced log-term neurological sequelae. DISCUSSION: From these experiences, the following risks factors for catheter rupture are identified: 1) intentional or accidental retraction of the catheter through the needle during placement; 2) faulty use of the guidewire; or 3) use of excessive force during removal of the catheter. Methods to prevent such complications are suggested, including minimal use, or complete avoidance of a guidewire.