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21.

Background

Routine preoperative laryngeal examination remains controversial. We aimed to assess the utility of preoperative routine flexible laryngoscopy (FL) by looking at the incidence, clinical significance and predictors for preoperative vocal cord paresis (VCP) and incidental laryngopharyngeal conditions (LPC) in our consecutive cohort.

Methods

A total of 302 patients underwent laryngeal examination by an independent otorhinolaryngologist and were specifically asked about voice/swallowing symptoms suggestive of VCP 1 day before surgery. As well as vocal cord (VC) mobility, the naso-pharynx and larynx were examined using FL. Any VCP and/or LPC was recorded. VCP was defined as reduced or absent movement in one or more VC. An LPC was considered clinically significant if the ensuing thyroidectomy was changed or deferred.

Results

Seven (2.3 %) patients had preoperative VCP, while an additional seven patients had an incidental LPC. Of the seven VCPs, five were caused by previous thyroidectomy, while two were caused by a benign goitre. The incidence of asymptomatic VCP in a previously non-operated cohort was 1/245 (0.41 %). Voice/swallowing symptoms (p = 0.033) and previous thyroidectomy (p < 0.001) were the two significant predictors for VCP. The seven incidental LPCs were vallecular cyst (n = 1), VC scar and polyp (n = 2), nasopharyngeal cyst and polyp (n = 3) and redundant arytenoid mucosa (n = 1); however, as they were benign, all seven patients proceeded to thyroidectomy as planned.

Conclusions

Given the low incidence (0.41 %) of asymptomatic VCP in a previously non-operated cohort and that none of the seven LPCs were considered clinically significant, routine preoperative laryngoscopic examination should be reserved for those with previous thyroidectomy and/or voice/swallowing symptoms.  相似文献   
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Objective

The aim of this study is to determine whether post-transarterial chemoembolization imaging (computed tomography or magnetic resonance imaging) could accurately predict the tumors' necrosis on pathologic specimens.

Background

Transarterial chemoembolization with drug-eluting beads has been proven to be an effective way to bridge patients with hepatocellular carcinomas to liver transplantation.

Materials and methods

From September 2012 to June 2017, 59 patients with a total of 78 hepatocellular carcinomas, who received transarterial chemoembolization with drug-eluting beads before liver transplantation in Kaohsiung Chang Gung Memorial Hospital, were included in the study. All patients and hepatocellular carcinomas have pre-transarterial chemoembolization and post-transarterial chemoembolization images (computed tomography or magnetic resonance imaging) and pathological findings for correlation. Tumor response was evaluated according to modified Response Evaluation Criteria in Solid Tumors. The ranges of necrotic percentage are 100%, 91-99%, 51-90%, and <50%.

Results

The accuracy rate between the imaging and pathology correlation was 40% for computed tomography and 42% for magnetic resonance imaging. The recurrent rate of the complete respond group is 11.5%, the partial respond group is 16.0%, and the stationary group is 28.6%.

Conclusion

Computed tomography and magnetic resonance imaging sensitivity is not satisfactory for microscopic evaluation of residual tumors after transarterial chemoembolization with drug-eluting beads. However, survival is good after liver transplantation no matter what the microscopic findings were.  相似文献   
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Overview: The use of pro-osteogenic growth factors, such as BMP2, in human adipose-derived stem cell (ASC) osteogenesis is well described. Because these growth factors work via signal transduction pathways, such as the mitogen-activated protein kinase (MAPK) cascade, a study of the relationship between MAPK signaling and ASC osteogenesis was conducted. Materials and Methods: ERK, JNK, and p38MAPK activation were measured in ASCs osteo-induced using either dexamethasone or vitamin D3 and correlated with mineralization. Activation and mineralization were also measured without dexamethasone or using the glucocorticoid, cortisone. The expression of the MAPK phosphatase, MKP1, and its relationship to mineralization was also assessed. The effect of decreasing MAPK activation on mineralization through the use of exogenous inhibitors was examined along with siRNA-knockdown and adenoviral overexpression of ERK1/2. Finally, the effect of ERK1/2 overexpression on ASCs induced on PLGA scaffolds was assessed. Results: ASC mineralization in dexamethasone or vitamin D3-induced ASCs correlated with both increased ERK1/2 and JNK1/2 activation. ASCs induced without dexamethasone also mineralized, with JNK1/2 signaling possibly mediating this event. No link between cortisone induction and MAPK signaling could be ascertained. ASCs treated with ERK, JNK, or p38MAPK inhibitors showed decreased osteogenic gene expression and diminished mineralization. Mineralization levels were also affected by viruses designed to inhibit or augment ERK1/2 expression and activity. Finally, ASC mineralization appeared to be a balance between the MAPK kinase activity and MKP1. Conclusions: It is likely that MAPK signaling plays a significant role in ASC osteogenesis, affecting differentiation in kinase- and stage-specific manners.  相似文献   
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AimsTo investigate the time-to-event and the evolution of sacral insufficiency fractures in gynaecological patients receiving pelvic external beam radiotherapy (EBRT) in relation to dosimetric and imaging parameters across a spectrum of radiotherapy delivery techniques, and to develop a predictive model with a clinical nomogram to identify those at risk of sacral insufficiency fracture.Materials and methodsPatients who received radical or adjuvant pelvic EBRT for gynaecological malignancy between 2014 and 2019 were identified. The data collected were: demographics and clinical details; radiotherapy planning data: dose, fractionation, technique (fixed-field intensity-modulated radiotherapy, adaptive arc, and non-adaptive arc), 60 Gy simultaneous integrated boost. Each plan was examined to determine the sacral dose in 5%/Gy3 increments. Follow-up magnetic resonance scans were reviewed for insufficiency fractures, defined as linear low T1-weighted signal intensity with a high short-T1 inversion recovery (STIR) signal. The site of insufficiency fracture was recreated on the planning computed tomography, the dose to insufficiency fracture contours was recorded and insufficiency fractures were determined as healed with resolution of high STIR signal. Univariable analysis was conducted of the clinical variables. The area under the receiver operator characteristic curve and odds ratio of the risk prediction model with 95% confidence interval are reported with a nomogram for use in clinical practice.Results115 patients were identified; the median imaging follow-up was 12 months (2–47). 37.4% developed sacral insufficiency fractures; 93.0% were detected within 12 months of EBRT. At the final radiological follow-up, 83.7% of insufficiency fractures remained active. The radiotherapy delivery technique was not associated with insufficiency fracture after adjusting for patient age (P = 0.115). The location of the 60 Gy simultaneous integrated boost planning target volume did not impact upon the site of insufficiency fracture or the dose received by the insufficiency fracture sites. Age and V40Gy3 are predictors for insufficiency fracture and form the clinical risk model (receiver operator characteristic 0.72).ConclusionsAge and V40Gy3 predict sacral insufficiency fractures; future work should focus on optimising radiotherapy planning with adoption of a bone-sparing planning approach for those patients at high risk of insufficiency fracture.  相似文献   
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