Dysphagia rates in single- and multiple-level anterior cervical discectomy and fusion surgery: a meta-analysis.

BACKGROUND: To conduct a meta-analysis to assess dysphagia complicating single-level and multiple-level (≥2) anterior cervical discectomy and fusion (ACDF) surgery. METHODS: Electronic searches were performed using four electronic databases from their inception to December 2017. Relevant studies reporting the rate of dysphagia as an endpoint for patients undergoing ACDF for degenerative disease, myelopathy, cervical canal stenosis or ossification of the posterior longitudinal ligament were identified according to prior inclusion and exclusion criteria. Statistical analysis was performed using a fixed effect model. P-scores were used to rank the levels of ACDF based on the rate of dysphagia. I2 was used to explore heterogeneity. RESULTS: Ten studies were identified and included in the systematic review and meta-analysis, with a total of 4,018 patients identified; 2,362 patients underwent single-level ACDF, while 1,656 underwent multiple level (≥2 ACDF). The mean age ranged from 49.45 to 57.77 years. Mean follow-up time ranged from 2 days to 27.3 months. Overall, meta-analysis demonstrated a statistically significant higher dysphagia rate for multiple-level ACDF (6.6%) than for single-level ACDF (4%) (P heterogeneity =0.151, OR =1.42, 95% CI: 1.05-1.91, I2=32%). CONCLUSIONS: Dysphagia is a relatively common complication in the early postoperative period following ACDF and may cause patients significant discomfort and distress. This meta-analysis demonstrates a higher rate of dysphagia with multiple-level ACDF than with single-level ACDF at a period of 12-24 months.

Vascular functioning and the water balance of ripening kiwifruit (Actinidia chinensis) berries.

Indirect evidence suggests that water supply to fleshy fruits during the final stages of development occurs through the phloem, with the xylem providing little water, or acting as a pathway for water loss back to the plant. This inference was tested by examining the water balance and vascular functioning of ripening kiwifruit berries (Actinidia chinensis var. chinensis 'Hort16A') exhibiting a pre-harvest 'shrivel' disorder in California, and normal development in New Zealand. Dye labelling and mass balance experiments indicated that the xylem and phloem were both functional and contributed approximately equally to the fruit water supply during this stage of development. The modelled fruit water balance was dominated by transpiration, with net water loss under high vapour pressure deficit (D(a)) conditions in California, but a net gain under cooler New Zealand conditions. Direct measurement of pedicel sap flow under controlled conditions confirmed inward flows in both the phloem and xylem under conditions of both low and high D(a). Phloem flows were required for growth, with gradual recovery after a step increase in D(a). Xylem flows alone were unable to support growth, but did supply transpiration and were responsive to D(a)-induced pressure fluctuations. The results suggest that the shrivel disorder was a consequence of a high fruit transpiration rate, and that the perception of complete loss or reversal of inward xylem flows in ripening fruits should be re-examined.

Selective tomographic imaging of patients with new-onset seizure disorders.

OBJECTIVE: Significant benefit could be realized by developing a clinical decision rule for new-onset seizure victims that would be capable of discriminating between patients having relevant structural lesions visible on computed tomographic (CT) imaging and those who do not. This study sought to determine whether a reliable decision rule could be developed using a limited number of clinical and demographic characteristics. METHODS: Chi-squared recursive partitioning was applied in a secondary analysis of the EMERGEncy ID NET database of new-onset seizure victims. Variables in this database (age, sex, race, ethnicity, seizure type, history of HIV or cysticercosis, and presence or absence of lateralizing neurologic findings or altered mentation) provided the partitioning variables, while CT imaging results provided outcome measures. The study sought to develop a decision rule with 100% sensitivity for detecting any intracranial lesions, and a separate rule with 100% sensitivity for detecting lesions of emergent concern. RESULTS: A decision rule using age > or = 65 years, lateralizing neurologic findings, altered mentation, high risk or known HIV infection, history of cysticercosis, and Hispanic ethnicity showed a sensitivity of 91.9% [95% confidence interval (95% CI) = 88.8% to 94.9%] in detecting individuals who had any tomographic finding. This rule had a sensitivity of 90.1% (95% CI = 83.4% to 96.7%) in detecting individuals with emergent tomographic findings. CONCLUSIONS: Recursive partitioning failed to produce a decision rule capable of reliably identifying new-onset seizure patients who have important lesions identified on CT. Future attempts to formulate such an instrument may need to include additional variables. In the interim, physicians should use liberal tomographic imaging in evaluating patients who present with new-onset seizures.