For patients with dysphagia resulting from upper esophageal sphincter dysfunction, strengthening the suprahyoid muscles through therapeutic exercise has proved effective in restoring oral feeding. The aim of this study was to compare the maximum and mean surface electromyography (sEMG) activity of the suprahyoid muscles during the Chin Tuck Against Resistance (CTAR) exercise and the Shaker exercise for both isokinetic and isometric tasks. During the CTAR exercises, the participant is seated while tucking the chin to compress an inflatable rubber ball, whereas during the Shaker exercise, the participant is lay supine while lifting the head to look at the feet. Forty healthy participants (20 males, 20 females) aged 21-39 years completed all four tasks in counterbalanced order, with measures of resting activation taken prior to each exercise. Although subjective feedback suggested that the sitting position for CTAR is less strenuous than the supine position for Shaker, the results of separate analyses showed significantly greater maximum sEMG values during the CTAR isokinetic and isometric exercises than during the equivalent Shaker exercises, and significantly greater mean sEMG values were observed for the CTAR isometric exercise than for the Shaker isometric exercise. Clinical trials are now needed, but the CTAR exercises appear effective in exercising the suprahyoid muscles, and they could achieve therapeutic effects comparable to those of Shaker exercises, with the potential for greater compliance by patients.

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It is believed that NPC most commonly spreads intracranially via the FL or by direct erosion. Perineural spread through the FO is an important route, which explains why with CT evidence of cavernous sinus involvement there may be no skull base erosion. These findings are best seen on MRI.

FDG-PET/CT is the most sensitive, specific, and accurate modality for distant metastasis staging of endemic NPC.

Neuroendocrine hepatic metastases exhibit various contrast uptake enhancement patterns in dynamic contrast-enhanced MRI. Using a dual-input two-compartment distributed parameter model, we analyzed the dynamic contrast-enhanced MRI datasets of seven patient study cases with the aim to relate the tumor contrast uptake patterns to parameters of tumor microvasculature. Simulation studies were also performed to provide further insights into the effects of individual microcirculatory parameter on the tumor concentration-time curves. Although the tumor contrast uptake patterns can be influenced by many parameters, initial results indicate that hepatic blood flow and the ratio of fractional vascular volume to fractional interstitial volume may potentially distinguish between the patterns of neuroendocrine hepatic metastases. Key words: neuroendocrine hepatic metastases; DCE MRI; tracer kinetics modeling Neuroendocrine tumors are a rare and heterogeneous group of hormone-secreting neoplasms that arise from neoplastic proliferation of enterochromaffin or Kulchitsky cells of the neuroendocrine system (1,2). Primary tumors can occur in various organs, predominantly in the gastrointestinal tract, pancreas, and lung. Despite their relatively low incidence, neuroendocrine tumors pose a significant clinical challenge due to their varied presentations and the primary tumor is often revealed through detection of metastases (2).Although neuroendocrine hepatic metastases have been described as predominantly hypervascular (1), in practice various contrast uptake enhancement patterns have been observed in dynamic contrast-enhanced (DCE) MRI, possibly due to their heterogeneous histology from diverse locations of origin. Apart from the usual contrast uptake pattern of rapid increase followed by rapid washout commonly associated with hypervascular hepatic lesions, neuroendocrine hepatic metastases can exhibit a spectrum of other contrast uptake behavior ranging from a progressively increasing pattern (within a few minutes following bolus administration of contrast medium) to patterns with an initial moderate increase followed by either a plateau, gradual increase or decrease.Although there are considerable interests in studying the various shapes of tumor contrast uptake patterns, the physiological basis of these patterns has remained unclear. Tracer kinetics analysis of these tumor contrast uptake patterns may provide insights into the differences in tumor microvasculature that result in these patterns. We aim to study the various contrast uptake patterns of neuroendocrine hepatic metastases and relate these patterns to tumor microcirculatory parameters derived from tracer kinetics modeling. MATERIALS AND METHODS Tracer Kinetics ModelingTracer kinetics modeling of the liver is uniquely challenging in two ways: (i) The liver has a dual blood supply derived from the hepatic artery and portal vein. (ii) Normal liver sinusoids are fenestrated, which allow free access of low-molecular weight compounds (including conventional gadolinium-bas...