Preliminary Prospective Preoperative and Postoperative Evaluation of Median Nerve Stiffness by Using Sonoelastography.

ABSTRACT: Carpal tunnel syndrome is the most common peripheral nerve entrapment syndrome. No previous studies have compared preoperative and follow-up sonoelastography results or investigated the correlation of median nerve stiffness with the subjective/objective outcomes. Therefore, the aim of this study was to compare the preoperative and postoperative elastography after carpal tunnel release and find the correlation with associated subjective/objective outcomes.From May 2017 to March 2020, 32 patients (6 males, 26 females; 34 hands) with carpal tunnel syndrome were enrolled in this prospective study. Demographic data, QuickDASH score (Chinese version), Boston Carpal Tunnel Questionnaire (Chinese version), nerve conduction velocity/electromyography, and median nerve stiffness by sonoelastography were recorded.Comparisons of preoperative and average sonoelastography findings 1.5 years postoperatively showed a significant decrease in stiffness presented by velocity (Vs) (preoperative Vs, 4.63 ± 1.27 m/s, vs postoperative Vs, 3.39 ± 0.59 m/s; P < 0.001). Changes in subjective functional outcomes also showed the same significant trend. Based on the neurophysiologic study, the improvement of nerve conduction study and elastography have the significant correlation.The same trend of preoperative and postoperative changes in median nerve stiffness and subjective questionnaires/objective neurophysiologic studies may imply that sonoelastography can be used to assess the response to surgery in patients with carpal tunnel syndrome.

Tracheal reconstruction with pedicled tandem grafts engineered by a radial stretch bioreactor.

The engineering of tracheal substitutes is pivotal in improving tracheal reconstruction. In this study, we aimed to investigate the effects of biomechanical stimulation on tissue engineering tracheal cartilage by mimicking the trachea motion through a novel radial stretching bioreactor, which enables to dynamically change the diameter of the hollow cylindrical implants. Applying our bioreactor, we demonstrated that chondrocytes seeded on the surface of Poly (ε-caprolactone) scaffold respond to mechanical stimulation by improvement of infiltration into implants and upregulation of cartilage-specific genes. Further, the mechanical stimulation enhanced the accumulation of cartilage neo-tissues and cartilage-specific extracellular macromolecules in the muscle flap-remodeled implants and reconstructed trachea. Nevertheless, the invasion of fibrous tissues in the reconstructed trachea was suppressed upon mechanical loading.

Simultaneous Paramedian Pedicle Forehead and Free Medial Sural Artery Perforator Flap Reconstruction of a Composite Nasal Defect: A Case Report.

BACKGROUND: Extensive nasal defects after resection of a malignancy are a challenge for all plastic surgeons. Nasal composite tissue defects have to be reconstructed with multiple staging surgeries. A paramedian pedicled forehead flap and free tissue transfer can be used for lining and skin replacement at different stages. In general, free tissue transfer is used for nasal lining and nasal floor reconstruction at the preliminary stage. Several weeks or months later, a paramedian pedicled forehead flap is used to replace the skin. Intermediate stages will also be necessary, and therefore the total therapeutic course is very long. AIM AND OBJECTIVES: The aim of this study was to report the simultaneous use of a paramedian pedicle forehead flap and a free medial sural artery perforator (MSAP) flap to reconstruct a composite nasal defect after wide excision of squamous cell carcinoma. PATIENT: In 2015, a 57-year-old woman with squamous cell carcinoma of the nose underwent tumor wide excision, which caused a composite defect involving multiple nasal subunits (partial tip, dorsum, right sidewall, right ala subunits). She received both a pedicled paramedian forehead flap to replace the skin and an MSAP flap to reconstruct the lining during the same procedure. At the intermediate stage 4 weeks later, the pedicled forehead flap was elevated and tailored. Then, a further 4 weeks later, flap division was performed. RESULTS: The patient received a total of 3 surgical procedures to reconstruct the composite defects of multiple nasal subunits. Nasal reconstruction was done within 2 months. The patient was satisfied with the aesthetic appearance and functional outcome. CONCLUSIONS: Simultaneous paramedian pedicle forehead and free flap reconstruction can provide an effective solution for composite nasal defects. Satisfactory functional and aesthetic results can be achieved.