Daisuke Kanamori

Changes in Pyriform Sinus Morphology in the Head Rotated Position as Assessed by 320-Row Area Detector CT

In patients with unilateral pharyngeal paresis and dysphagia, the head is rotated to the paretic side to prevent food flow to the rotated side during swallowing. Only a few studies to date have reported on pyriform sinus morphology upon head rotation. The purpose of this study was to measure the volume, depth, and cross-sectional area of the pyriform sinus during head rotation using 320-row area detector computed tomography. We imaged the neck during head rotation at 0° and at 30°, 45°, and 60° to the left or right in nine healthy young adults and determined the volume, depth, and cross-sectional area of the pyriform sinus in each position. On the rotated side, volume and cross-sectional area were significantly decreased at 60°. In contrast, volume, cross-sectional area, and depth were all significantly increased on the opposite side at 60°. These results suggest that head rotation at 60° significantly increases the volume, cross-sectional area, and depth of the opposite side, and significantly decreases the volume and depth of the rotated side of the pyriform sinus.

Isolated Pharyngeal Swallow Exists during Normal Human Feeding

Swallowing is one of the basic activities in humans. The pharynx functions as an airway and a food channel, and a pharyngeal swallow usually occurs after bolus transport from the oral cavity. However, direct fluid infusion through a catheter into the hypopharynx produces a pharyngeal swallow without the oral stage in experimental situations. The purpose of this study was to examine whether a pharyngeal swallow, which is not accompanied by bolus transport, can occur during normal human feeding. Fifty-three healthy volunteers (25-89 years) were recorded, via videofluoroscopic examination of swallowing, during 3 different swallowing trials: command swallow of 10 ml liquid barium, chew-swallow of corned beef, and chew-swallow of a mixture of corned beef and liquid barium. Subsequently each swallow was classified as being either a consecutive pharyngeal swallow (CPS), following transport, or an isolated pharyngeal swallow (IPS), without immediately prior transport. The location of the bolus at swallow initiation was also noted. Of 307 trials, 681 swallows were identified, which included 43 IPS and 638 CPS. IPS only occurred as the first swallow of a trial, but the frequency of IPS did not differ between 28 younger (< 60 years) and 25 older (≥ 60 years) people. Of the three food types, IPS occurred more frequently with the mixed food than with liquid. These results suggest that IPS may represent an airway protective mechanism. In conclusion, IPS occurs in normal swallowing during a daily eating situation. Swallowing is more complex than a simple reflex.

Classification of sequential swallowing types using videoendoscopy with high reproducibility and reliability

ObjectiveThis study aimed to classify sequential swallowing types using videoendoscopy (VE) avoiding radiation exposure and compare the results using videofluoroscopy (VF). DesignTwenty-one healthy adults simultaneously underwent VF and VE during sequential straw drinking. Each discrete swallow was classified into an L-segmental type (laryngeal vestibule opens after swallow) or L-continuous type (laryngeal vestibule closure continues after swallow) using VF and a V-segmental type (velopharynx opens after swallow) or V-continuous type (velopharynx closure continues after swallow) using VE. Test-retest reproducibility and interrater and intrarater reliability were evaluated in ten healthy adults. ResultsOf 128 swallows, 94 were L-segmental and 34 were L-continuous types as per VF, whereas 95 were V-segmental and 33 were V-continuous types as per VE. The leading edge of the bolus at swallow onset was significantly deeper in L-continuous types (P = 0.001). Laryngeal vestibule closure on VF images corresponded to velopharyngeal closure on VE images for 127 of 128 swallows (&kgr; = 0.98, P < 0.001). All subjects showed the same types of swallows in the first and the second studies. Both interrater and intrarater reliability were high. ConclusionVE showed high reproducibility and reliability in the classification of sequential swallowing types.

Does oral care contribute to brain activation?: One case of functional near-infrared spectroscopy study in patients with a persistent disturbance of consciousness

We used functional near‐infrared spectroscopy (fNIRS) to measure cerebral blood flow during oral care in a patient with persistent disturbance of consciousness. We experienced that cerebral blood flow to frontal area increased during oral care, suggesting that oral care may have a potential role in rehabilitation for the brain.