Changes in oral health status in terminal cancer patients during the last weeks of life.

BACKGROUND: Many studies have shown deterioration of the oral health environment in palliative care patients; however, most of these studies are cross-sectional. In this longitudinal observational study, we aimed to determine the oral symptoms and how they change in palliative care patients. METHODS: The participants were 82 patients (37 men, 45 women) admitted to two palliative care units in Japan between January 2018 and December 2021. The oral condition was evaluated once a week from the time of admission using the Oral Health Assessment Tool (OHAT) and performance status (PS). Friedman tests were performed on the OHAT and PS scores at 1, 2, and 3 weeks before the week of death. In addition, the Bonferroni method was used to determine how many weeks before death the changes occurred. RESULTS: PS continuously deteriorated from three weeks before death. The total OHAT score 2 weeks before death (3.44±2.10) was significantly different compared to that in the week of death (4.37±2.45). In terms of oral conditions, the properties of the saliva changed, and dry mouth became obvious. CONCLUSIONS: The results of this study revealed that the oral environment of palliative care patients became significantly dry 2 weeks before death, suggesting that it may be useful for predicting the stage of death.

The Comparison of Postoperative Umbilical Port Site-Related Complications Between Transumbilical and Periumbilical Incision After Laparoscopic Surgery in Children.

Introduction: No studies have directly compared postoperative umbilical port site (UPS)-related complications between transumbilical and periumbilical incisions (TUI and PUI) after laparoscopic surgery in children. Patients and Methods: We conducted a retrospective review of 324 children of ≤15 years of age who underwent laparoscopic repair (LR) for inguinal hernia, via either a TUI or PUI, between 2010 and 2020. UPS-related complications, such as wound infection and umbilical deformity, were compared between TUI and PUI. We also investigated the risk factors for the development of UPS-related complications after LR. Results: TUIs and PUIs were used for 228 and 96 children, respectively. The incidence rates of postoperative wound infection and umbilical deformity in the PUI group were higher in comparison to the TUI group; although not to a statistically significant extent (7.3% versus 5.3%, P = .451, 6.3% versus 4.8%, P = .593). One case of incisional hernia at the UPS was seen in the TUI group. In the univariate analysis, sex, age, weight for age Z-score, nutrition status, insertion and closure time, total operative time, American Society of Anesthesiologists score, blood loss, and comorbidities were not significantly associated with the development of UPS-related complications after LR. Conclusion: The incidence of UPS-related complications in TUI and PUI was not significantly different. Due to the low incidence of UPS-related complications, it was difficult to draw conclusions regarding contributing factors; however, meticulous care should be taken to avoid UPS-related complications when closing the UPS (Ethical approval No. 2019-24).

Increase in pediatric complicated appendicitis during the COVID-19 pandemic: a multi-center retrospective study.

PURPOSE: An increase in the incidence of pediatric complicated appendicitis (CA) during the COVID-19 pandemic has been reported in many countries. We investigated how the pandemic has affected Japan. METHODS: We retrospectively reviewed children of ≤ 15 years old treated for acute appendicitis across 5 medical centers during the pandemic period (January to October in 2020), with the pre-pandemic period (January to October in 2017 to 2019) evaluated as a historical control. The incidence of CA and disease characteristics were then compared between the periods. RESULTS: The total number of patients was 55 in 2020 and 192 in 2017-2019. In all centers, the incidence of acute pediatric CA in the pandemic period significantly increased compared to the pre-pandemic period (18.2% vs. 32.7%, p = 0.02). On limiting our evaluation to the 3 institutions with reductions in patient numbers, the incidence of CA increased (16.3% vs. 37.9%, p = 0.01), and the duration of pre-operative symptoms was prolonged (1.3% vs. 1.7 days, p = 0.03). There were no significant differences in the age, sex, white blood cell count, C-reactive protein, or body temperature. No cases were diagnosed with SARS-CoV-2. CONCLUSIONS: The incidence of acute pediatric CA increased during the pandemic period. This may be related to an extended duration of symptoms due to individuals fearing contracting COVID-19 while visiting a hospital.

Risks and benefits of pediatric inguinal hernia repair: Conventional open repair vs laparoscopic percutaneous extraperitoneal closure.

INTRODUCTION: Considerable debate exists regarding the benefits of laparoscopic percutaneous extraperitoneal closure (LPEC) over conventional open repair (OR). We assessed the outcomes and feasibility of LPEC compared to OR for pediatric inguinal hernia (IH). METHODS: We retrospectively analyzed 570 children who underwent LPEC or OR. Parents decided the operative method after obtaining informed consent. Patient characteristics, operative time, complications and contralateral metachronous IH (CMIH) were compared between the groups. RESULTS: A total of 329 children underwent LPEC and 241 underwent OR. There was no significant difference in the incidence of recurrence or testicular ascent between the LPEC and OR groups (0.3% vs 0.4%, P = 0.825, 0.3% vs 0.8%, P = 0.391, respectively). No testicular atrophy was recognized in either group. One patient with postoperative chronic inguinal pain was recognized in each group. There was no surgical site infection (SSI) in the OR group; however, the LPEC group more frequently demonstrated umbilical port site (UPS)-related complications, such as incisional hernia, minor deformity, granuloma formation, cellulitis and superficial SSI. Ten (4.1%) developed CMIH in OR; in contrast, no case of CMIH was experienced after LPEC (P < 0.001). CONCLUSION: In conclusion, both LPEC and OR are feasible in the management of pediatric IH, because of their high success rates and low risk of complications. LPEC could be the superior procedure with respect to the prevention of CMIH. However, to maximize the merits of LPEC over OR, it is important to reduce UPS-related complications in LPEC. A longer follow-up is needed to assess male fertility in patients who receive LPEC.

Evaluation of Velopharyngeal Closure Function With 4-Dimensional Computed Tomography and Assessment of Radiation Exposure in Pediatric Patients: A Cross-Sectional Study.

OBJECTIVE: Some patients with cleft palate (CP) need secondary surgery to improve functionality. Although 4-dimensional assessment of velopharyngeal closure function (VPF) in patients with CP using computed tomography (CT) has been existed, the knowledge about quantitative evaluation and radiation exposure dose is limited. We performed a qualitative and quantitative assessment of VPF using CT and estimated the exposure doses. DESIGN: Cross-sectional. SETTING: Computed tomography images from 5 preoperative patients with submucous CP (SMCP) and 10 postoperative patients with a history of CP (8 boys and 7 girls, aged 4-7 years) were evaluated. PATIENTS: Five patients had undergone primary surgery for SMCP; 10 received secondary surgery for hypernasality. MAIN OUTCOME MEASURES: The presence of velopharyngeal insufficiency (VPI), patterns of velopharyngeal closure (VPC), and cross-sectional area (CSA) of VPI was evaluated via CT findings. Organ-absorbed radiation doses were estimated in 5 of 15 patients. The differences between cleft type and VPI, VPC patterns, and CSA of VPI were evaluated. RESULTS: All patients had VPI. The VPC patterns (SMCP/CP) were evaluated as coronal (1/4), sagittal (0/1), circular (1/2), and circular with Passavant's ridge (2/2); 2 patients (1/1) were unevaluable because of poor VPF. The CSA of VPI was statistically larger in the SMCP group (P = .0027). The organ-absorbed radiation doses were relatively lower than those previously reported. CONCLUSIONS: Four-dimensional CT can provide the detailed findings of VPF that are not possible with conventional CT, and the exposure dose was considered medically acceptable.

Effect of tongue-hold swallow on posterior pharyngeal wall using dynamic area detector computed tomography.

PURPOSE: The purpose of this study was to elucidate the effects of the tongue-hold swallow (THS) on the pharyngeal wall by quantifying posterior pharyngeal wall (PPW) anterior bulge during the THS. In addition, the effect of tongue protrusion length on the extent of pharyngeal wall anterior bulge was analysed. METHODS: Thirteen healthy subjects (6 males and 7 females, 23-43 years) underwent 320-row area detector CT during saliva swallow (SS) and THS at two tongue protrusion lengths (THS1 protrude the tongue as much as 1/3 of premeasured maximum tongue protrusion length (MTP-L) and THS2 protrude the tongue as much as 2/3 of MTP-L). To acquire images of the pharynx at rest, single-phase volume scanning was performed three times during usual breathing with no tongue protrusion (rest), protrusion of the tongue at 1/3 of MTP-L (rTHS1) and protrusion of the tongue at 2/3 of MTP-L (rTHS2). Length from cervical spine to PPW (PPW-AP) and the volume of pharyngeal cavity was measured and was compared between rest, rTHS1 and rTHS2 and between SS, THS1 and THS2. Correlation between MTP-L and PPW-AP was calculated in three conditions, SS, THS1 and THS2. RESULTS: PPW-AP at rest, rTHS1 and rTHS2 was 2.9 ± 0.6 mm, 3.0 ± 0.5 mm and 3.0 ± 0.5 mm, respectively, showing no significant differences across swallows. PPW-AP at the maximum pharyngeal constriction was 8.1 ± 2.0 mm, 9.1 ± 2.4 mm and 8.7 ± 2.0 mm in SS, THS1 and THS2, respectively. Compared to SS, PPW-AP in THS1 was significantly larger (p = 0.04) and PPW-AP in THS2 was not significantly different (p = 0.09). Pharyngeal volume at rest, rTHS1 and rTHS2 was 16.4 ± 5.2 mm3 , 18.4 ± 4.5 mm3 and 21.3 ± 6.2 mm3 , respectively. It was significantly larger during rTHS2 compared with rest or rTHS1 (rTHS2-rest p = 0.007, rTHS2-rTHS1 p = 0.007). Pharyngeal volume was completely obliterated (zero volume) at maximum pharyngeal contraction in all except one subject. There was no correlation between MTP-L and PPW-AP in any of the three conditions (SS, THS1 and THS2). DISCUSSION: This study demonstrated that the expanded pharyngeal cavity due to the tongue protrusion was completely obliterated by the increase in anterior motion of pharyngeal wall during THS. It also became clear that the degree of tongue protrusion did not linearly correlate with the movement of PPW during THS. There was no relationship between PPW motion and the MTP-L, suggesting that the effect of tongue protrusion is better determined in each subject by analysing the motion of PPW using imaging tools.

Effect of morphological findings in computed tomography on the quantitative values in single-photon emission computed tomography for patients with antiresorptive agent-related osteonecrosis of the jaw: a cross-sectional study.

OBJECTIVE: Quantitative analyses of gamma-ray accumulation in single-photon emission computed tomography (SPECT), and the evaluation of antiresorptive agent-related osteonecrosis of the jaw (ARONJ) have been reported recently. However, the relationship between the quantitative parameters calculated from SPECT and the detailed morphological changes observed in computed tomography (CT) remains unclear. This study aimed to investigate patients' characteristics and morphological changes observed on CT, and their effects on the quantitative values in SPECT. METHODS: From April 2017 to March 2019, patients diagnosed with ARONJ at our hospital were enrolled. The data obtained before September 2017 were reviewed retrospectively, and other data were collected prospectively. CT scans were evaluated for internal texture, sequestrum formation, periosteal reaction, cortical perforation, bone expansion, and pathological fracture. For quantitative assessment, the ratio of the maximum standardized uptake value (SUV) to the mean SUV in the temporal bone (rSUVmax) was calculated from SPECT images. The factors affecting rSUVmax were investigated by multiple regression analysis. The statistical significance level was set at α = 0.05. RESULTS: Overall, 55 lesions of 42 patients (median age and interquartile range, 75 [67-80 years], 27 female) were evaluated. Male sex (p = 0.007) and bilateral location (p < 0.0001) were selected as variables in the multivariate analysis. Adjusted coefficient of determination R2 was 0.59 (p < 0.0001). CONCLUSION: Sex and horizontal progression of the disease may affect individually calibrated SUVs in SPECT for patients with ARONJ.

Velopharyngeal closure analysis using four-dimensional computed tomography: a pilot study of healthy volunteers and adult patients with cleft palate.

BACKGROUND: Nasopharyngoscopy is a common method to evaluate velopharyngeal closure in patients with cleft palate. However, insertion of a fiberoptic nasopharyngoscope causes discomfort in patients. The aim of this study was to estimate the reliability of short-time exposure images obtained using 320-row area detector computed tomography (320-ADCT) as a novel evaluation method for the assessment of velopharyngeal function. METHODS: We evaluated five healthy adult volunteers and five postoperative adult patients with cleft palate. During a 3.3-s imaging exposure, the participants were asked to perform two tasks: nasal inspiration and subsequent oral expiration through a catheter into a water-filled cup. The movement of the velopharyngeal structures was recorded during each examination, and the presence of velopharyngeal insufficiency (VPI) and velopharyngeal closure (VPC) patterns were estimated. If VPI was detected, the cross-sectional area was also calculated. Cohen's kappa and weighted kappa coefficients were used to evaluate the concordance of nasopharyngoscopy and 320-ADCT evaluation. RESULTS: Speech pathology evaluation did not reveal hypernasality in any study participant. Micro-VPI was detected by nasopharyngoscopy in one healthy volunteer and two patients. 320-ADCT detected micro-VPI in two more patients. The cross-sectional area of the VPI in these subjects ranged from 2.53 to 16.28 mm2. Nasopharyngoscopy and 320-ADCT were concordant in detecting VPI in eight participants (κ = 0.6) and in assessing VPC patterns in nine (κ = 0.82). Moreover, images obtained using 320-ADCT allowed for reduced dead angle and, thus, easy detection of micro-VPI and Passavant's ridges. CONCLUSION: Although the radiation exposure cannot be ignored, our novel evaluation method using 320-ADCT enables more detailed evaluation of VPC than nasopharyngoscopy. Future studies should investigate the relationship between 320-ADCT findings and speech pathology evaluations.

Thalidomide potentiates etoposide-induced apoptosis in murine neuroblastoma through suppression of NF-κB activation.

PURPOSE: Treatment for high-risk neuroblastoma is still challenging. The purpose of the present study was to determine whether thalidomide suppresses etoposide-induced NF-κB activation and thus potentiates apoptosis in murine neuroblastoma. METHODS: A murine neuroblastoma cell line, C1300, and A/J mice were used in this study. We evaluated NF-κB activation after using etoposide with or without thalidomide by quantitative analysis of NF-κB by ELISA and by Western blot analysis of IκB phosphorylation in vitro and in vivo. Induction of apoptosis was evaluated by Western blot analysis of the apoptotic signals caspase-3, 8, and 9 in vitro and by TUNEL assays in vivo. We also evaluated the efficacy of the combination of etoposide and thalidomide by assessing tumor growth and mouse survival in vivo. RESULTS: Etoposide activated NF-κB in C1300 cells. This activation was suppressed by thalidomide and IκB was re-upregulated. The apoptotic signals were enhanced by the combination of thalidomide and etoposide compared with etoposide alone in vitro, which was consistent with TUNEL assays. The combination of etoposide and thalidomide also slowed tumor growth and mouse survival. CONCLUSION: Thalidomide potentiates etoposide-induced apoptosis in murine neuroblastoma by suppressing NF-κB.

Measurement of Pharyngo-laryngeal Volume During Swallowing Using 320-Row Area Detector Computed Tomography.

This study aimed to (1) evaluate changes in bolus and air volumes in the pharyngo-laryngeal cavity during swallowing and (2) determine how differences in these volumes during swallowing are influenced by bolus amount using 320-row area detector computed tomography (320-ADCT). Three-, 10-, and 20-ml honey-thick liquids (5% w/v) were presented to ten healthy subjects placed in a 45° reclining position. 3D images were created in 29 phases at an interval of 0.1 s for 3.15 s. Changes in bolus and air volumes in the pharyngo-laryngeal cavity were calculated. The two one-sided tests were used to determine equivalency of the pharyngo-laryngeal volume of each event (i.e., onset of hyoid elevation, soft palate closure, true vocal cord closure, closure of laryngeal vestibule, epiglottis inversion, pharyngo-esophageal sphincter opening) for each bolus volume. The pharyngo-laryngeal volume during swallowing was about 20 ml before swallowing. The volume temporarily increased with tongue loading, but decreased to about 0 ml with pharyngeal contraction. Subsequently, the volume returned to the original volume after airway opening. Most of the air was released from the pharyngo-laryngeal space before the bolus flowed into the esophagus during swallowing. As the bolus volume to be swallowed increased, the maximal pharyngo-laryngeal volume increased, but changes in air volume remained constant. 320-ADCT allowed for analysis of dynamic volume changes in the pharyngo-laryngeal cavity, which will increase our knowledge of kinematic and volumetric mechanisms during swallowing.

Initiation of Pharyngeal Response during Discrete Swallowing and Chew-swallowing in Healthy Subjects.

OBJECTIVE: The aim of this study was to measure the initiation of pharyngeal swallowing during discrete swallowing and during chew-swallowing in younger and older healthy subjects and to determine the normal range of the stage transition duration (STD) for different food boluses. The correlations between STDs were investigated. METHODS: Twenty-eight younger subjects (< 60 years old) and 25 older subjects (≥ 60 years old) were enrolled. While in the sitting position, the subjects swallowed 10 ml of thin liquid barium (LQ), 8 g of corned beef hash with barium (CB), 8 g of cookie with barium (CK), and a two-phase mixture of 4 g of corned beef hash with barium and 5 ml of thin liquid barium (MX). A videofluoroscopic examination of swallowing was performed at 30 frames/s in the lateral projection. The delay in pharyngeal swallowing (i.e., STD) was measured. The normal range (mean ± 2SD) of STDs for each bolus type was determined, and correlations were calculated to examine the relationship among STDs. RESULTS: The median STDs for LQ, CB, CK, and MX in all subjects were 0.0, 1.2, 2.4, and 1.9 s, respectively. The STDs were prolonged for CB, CK, and MX compared with LQ. Additionally, the median STD was longer for LQ, CB, and CK in older than in younger subjects. No significant correlations were found between STDs except for those between CB and CK. CONCLUSIONS: A delayed pharyngeal response is commonly observed during chew-swallowing. Liquids, solids, and two-phase mixtures exhibit independent timings of pharyngeal swallow initiation.

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.

Effect of Scopolamine Butylbromide on Clozapine-induced Hypersalivation in Schizophrenic Patients: A Case Series.

Clozapine has been demonstrated to be useful for treating refractory schizophrenia. However, hypersalivation occurs in 31.0- 97.4% of the patients treated with clozapine. Accordingly, some patients who are disturbed by their hypersalivation refuse to continue with clozapine treatment. This study investigated the efficacy of the anticholinergic agent scopolamine butylbromide against clozapine-induced hypersalivation. Five schizophrenia patients were coadministered scopolamine butylbromide (30-60 mg/ day) for 4 weeks. At the baseline and after 4 weeks' treatment, we subjectively evaluated hypersalivation using a visual analog scale and objectively assessed it using the Drooling Severity Scale and Drooling Frequency Scale. As a result, improvements in the patients' Drooling Severity Scale and Drooling Frequency Scale scores, but no improvements in their visual analog scale scores, were observed after scopolamine butylbromide treatment. These results indicate that at least some schizophrenic patients with clozapine-induced hypersalivation would benefit from scopolamine butylbromide treatment. We conclude that clozapine-induced hypersalivation is one factor of stress to patients. Subjective hypersalivation was not improved, but objective hypersalivation was, by scopolamine butylbromide treatment. However, scopolamine butylbromide and clozapine possess anticholinergic effects so clinicians should closely monitor patients who take scopolamine butylbromide.

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

OBJECTIVE: This study aimed to classify sequential swallowing types using videoendoscopy (VE) avoiding radiation exposure and compare the results using videofluoroscopy (VF). DESIGN: Twenty-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. RESULTS: Of 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 (κ = 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. CONCLUSION: VE 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.

KEY CLINICAL MESSAGE: 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.

Effective elimination of contaminants after oral care in elderly institutionalized individuals.

After mechanical cleaning in oral care, eliminating residual oral contaminants has an important role in preventing their aspiration, especially in individuals with weak airway protection. We examined the effectiveness of wiping the oral cavity after oral care on eliminating contaminants in 31 patients who were hospitalized in our neurology inpatient unit. The amount of bacteria on the tongue, palate, and buccal vestibule was counted before and just after oral care, after eliminating contaminants either by rinsing with water and suction or by wiping with mouth wipes, and 1 h after oral care. Oral bacteria amounts were decreased significantly by both elimination procedures after oral care. These findings suggest that wiping with mouth wipes is as effective as mouth rinsing to decrease bacteria following oral care. With a lower risk of contaminant aspiration, wiping may be a suitable alternative to rinsing, especially in dysphagic individuals.

Laparoscopic percutaneous extraperitoneal closure for inguinal hernia: learning curve for attending surgeons and residents.

BACKGROUND/PURPOSE: Laparoscopic percutaneous extraperitoneal closure (LPEC) for pediatric inguinal hernia is a simple technique in which a purse-string suture made of nonabsorbable material is placed extraperitoneally around the hernia orifice by a special suture needle (Lapaherclosure™). Concerns have been raised about the extensive learning curve for both attending surgeons and residents to master this technique. This study assesses the difference in learning curves for the safe performance of LPEC by attending surgeons and residents. METHODS: A retrospective analysis was performed on the surgical charts of 409 consecutive patients (175 girls, 234 boys) who had undergone LPEC for inguinal hernia repair from December 2005 to December 2011 at Jikei University Hospital. The number of operation needed by attending surgeons and residents to reach the appropriate operation time was analyzed by the Mann-Whitney U test. RESULTS: LPEC was performed by three attending surgeons and four residents who had not previously performed LPEC. The standard operation time for LPEC by attending surgeons who have performed more than 100 LPEC cases safely is 30 min. In our study, the attending surgeons needed a mean of 12 operations (range, 10-16) to reach 30 min for LPEC. Three residents needed a mean of 31 operations (range, 27-33) to reach 30 min for LPEC. The fourth resident could not perform LPEC in 30 min or less. The difference between the number of operations needed by the attending surgeons and the residents to perform LPEC safely was statistically significant (P < 0.05). The overall incidence of contralateral patent processus vaginalis was 47.9 %. CONCLUSIONS: Our learning curve analysis showed that whereas attending surgeons needed a mean of 12 operations to perform LPEC repairs safely in 30 min or less, residents needed more than 30 operations to safely perform LPEC repairs without supervision.

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.

Evaluation of swallowing using 320-detector-row multislice CT. Part II: kinematic analysis of laryngeal closure during normal swallowing.

The purpose of this study was to (1) depict normal dynamic swallowing and (2) measure (a) the temporal characteristics of three components of laryngeal closure, i.e., true vocal cord (TVC) closure, closure of the laryngeal vestibule at the arytenoid to epiglottic base, and epiglottic inversion, and (b) the temporal relationship between these levels of laryngeal closure and other swallowing events, hyoid elevation, and the pharyngoesophageal segment (PES) using 320-detector-row multislice computed tomography (320-MSCT). The swallowing of a 10-ml portion of honey-thick liquid (5% w/v) was examined in six healthy volunteers placed in a 45° reclining position. Three-dimensional CT images were created in 29 phases at an interval of 0.10 s over a 2.90-s duration. Dynamic swallowing and TVC movement were depicted clearly. The sequence for laryngeal closure was the following: (1) the hyoid started to elevate, (2) the PES opened, (3) TVC closure and closure at the arytenoid to epiglottic base occurred almost simultaneously during the hyoid elevation, and (4) the epiglottic maximum inversion occurred after the hyoid maximum displacement. Those results indicated that the onset of hyoid elevation and the early opening of the PES occurring before three levels of laryngeal closure are critical components for airway protection. 320-MSCT allowed the 3D depiction and kinematic analysis of target structures, which will increase our knowledge of airway protection mechanisms during swallowing.

Contribution of the intramolecular hydrogen bond to the shift of the pKa value and the oxidation potential of phenols and phenolate anions.

Intramolecularly OHO[double bond, length as m-dash]C hydrogen bonded phenols, 2-HO-C6H2-3,5-(t-Bu)2-CONH-t-Bu (1-OH), 2-HO-C6H2-5-t-Bu-1,3-(CONH-t-Bu)2 (2-OH) and 2-HO-C6H2-3,5-(t-Bu)2-NHCO-t-Bu (4-OH), were synthesized and their phenolate anions were prepared as tetraethylammonium salts (-1O-(NEt4+), 2-O-(NEt4+) and 4-O-(NEt4+)) with intramolecular NHO(oxyanion) hydrogen bonds. 4-HO-C(6)H(2)-3,5-t-Bu(2)-CONH-t-Bu (3-OH) and its phenolate anion, 3-O-(NEt4+), were synthesized as non-hydrogen bonded references. The presence of intramolecular hydrogen bonds was established through the crystallographic analysis and/or (1)H NMR spectroscopic results. Intramolecular NHO(phenol) hydrogen bonds shift the pK(a) of the phenol to a more acidic value. The results of cyclic voltammetry show that the intramolecular OH...O=C hydrogen bond negatively shifts the oxidation potential of the phenol. In contrast, the intramolecular NHO(oxyanion) hydrogen bond positively shifts the oxidation potential of the phenolate anion, preventing oxidation. These contributions of the hydrogen bond to the pKa value and the oxidation potentials probably play an important role in the formation of a tyrosyl radical in photosystem II.