Comparison of T2 values of the displaced unilateral disc and retrodiscal tissue of temporomandibular joints and their implications.

Unilateral anterior disc displacement (uADD) has been shown to affect the contralateral joints qualitatively. This study aims to assess the quantitative T2 values of the articular disc and retrodiscal tissue of patients with uADD at 1.5 Tesla (T). The study included 65 uADD patients and 17 volunteers. The regions of interest on T2 maps were evaluated. The affected joints demonstrated significantly higher articular disc T2 values (31.5 ± 3.8 ms) than those of the unaffected joints (28.9 ± 4.5 ms) (P < 0.001). For retrodiscal tissue, T2 values of the unaffected (37.8 ± 5.8 ms) and affected joints (41.6 ± 7.1 ms) were significantly longer than those of normal volunteers (34.4 ± 3.2 ms) (P < 0.001). Furthermore, uADD without reduction (WOR) joints (43.3 ± 6.8 ms) showed statistically higher T2 values than the unaffected joints of both uADD with reduction (WR) (33.9 ± 3.8 ms) and uADDWOR (38.9 ± 5.8 ms), and the affected joints of uADDWR (35.8 ± 4.4 ms). The mean T2 value of the unaffected joints of uADDWOR was significantly longer than that of healthy volunteers (P < 0.001). These results provided quantitative evidence for the influence of the affected joints on the contralateral joints.

Inverse planning optimization with lead block effectively suppresses dose to the mandible in high-dose-rate brachytherapy for tongue cancer.

PURPOSE: In this study, we developed in-house software to evaluate the effect of the lead block (LB)-inserted spacer on the mandibular dose in interstitial brachytherapy (ISBT) for tongue cancer. In addition, an inverse planning algorithm for LB attenuation was developed, and its performance in mandibular dose reduction was evaluated. METHODS: Treatment plans of 30 patients with tongue cancer treated with ISBT were evaluated. The prescribed dose was 54 Gy/9 fractions. An in-house software was developed to calculate the dose distribution based on the American Association of Physicists in Medicine (AAPM) Task Group No.43 (TG-43) formalism. The mandibular dose was calculated with consideration of the LB attenuation. The attenuation coefficient of the lead was computed using the PHITS Monte Carlo simulation. The software further optimized the treatment plans using an attraction-repulsion model (ARM) to account for the LB attenuation. RESULTS: Compared to the calculation in water, the D2 cc of the mandible changed by - 2.4 ± 2.3 Gy (range, - 8.6 to - 0.1 Gy) when the LB attenuation was considered. The ARM optimization with consideration of the LB resulted in a - 2.4 ± 2.4 Gy (range, - 8.2 to 0.0 Gy) change in mandibular D2 cc. CONCLUSIONS: This study enabled the evaluation of the dose distribution with consideration of the LB attenuation. The ARM optimization with lead attenuation further reduced the mandibular dose.

Distant metastasis from oral cavity-correlation between histopathology results and primary site.

OBJECTIVES: Oral cancer is the eighth most common type of cancer worldwide and a significant contributor to the global burden caused by this disease. The principal parameters considered to influence prognosis, and thus treatment selection, are size and location of the primary tumor, as well as assessment of the presence and extent of lymph node and distant metastasis (DM). However, no known report regarding the relationship between the primary site and DM has been presented. For effective treatment selection and good prognosis, the correlation of DM with anatomic site and histopathology results of the primary malignancy is important. In the present study, we performed a systematic review of published reports in an effort to determine the relationship between the anatomic site of various types of oral cavity cancer and DM. METHODS: A systematic review of articles published until the end of 2018 was performed using PubMed/MEDLINE. RESULTS: A total of 150 studies were selected for this review. The percentage of all cases reported with DM was 6.3%, ranging from 0.6% to 33.1% in the individual studies. The rate of incidence of tongue occurrence was 9.3%. A frequent DM site was the lungs, with adenoid cystic carcinoma the most commonly involved histopathological factor. Malignant melanoma was most frequent (43.4%) in all histopathology findings, whereas there were no cases with an acinic cell carcinoma or cystadenocarcinoma. CONCLUSIONS: We found that the occurrence of DM from the primary site as well as rate of incidence was dependent on histopathological factors.

Diffusion-weighted magnetic resonance imaging of the oral and maxillofacial region: optimal fat suppression method.

OBJECTIVE: To compare 3 fat suppression methods-water excitation (WE), chemical shift selective (CHESS), and short T1 inversion recovery (STIR)-for optimal image quality and apparent diffusion coefficient (ADC) values with magnetic resonance imaging (MRI) using diffusion-weighted imaging (DWI) of the oral and maxillofacial region. STUDY DESIGN: In total, 53 patients with 73 lesions were enrolled in this study. MRI using DWI protocols with the 3 fat suppression methods were performed in addition to a conventional MRI protocol. The diagnostic image quality of lesions, image uniformity, degree of image artifacts, and ADC values of the lesions were evaluated. Average visual scores and ADC values were compared, and post hoc pairwise comparisons were performed, with the level of significance set at P < .0167. RESULTS: Diagnostic image quality was not significantly different among the fat suppression methods (P ≥ .042). Image uniformity was significantly higher (P < .001), and the degree of image artifacts was significantly lower (P < .001), in images using the STIR method. Mean ADC values did not differ significantly among the 3 methods. CONCLUSIONS: The STIR method was the most useful fat suppression method for DWI of the oral and maxillofacial region because of its high level of image uniformity and few image artifacts.

Evaluation of the effectiveness of the sliding sheet in repositioning care in terms of working time and subjective fatigue: A comparative study with an experimental design.

BACKGROUND: Manual patient handling is a major cause of low back pain among healthcare staff. The sliding sheet is an assistive device designed to aid healthcare staff performing patient repositioning in bed. The use of sliding sheets in healthcare facilities is currently relatively rare because of the perceived additional time required compared with non-assisted handling. However, the details of the time difference between techniques and the barriers to the use of sliding sheets have not been examined in depth. OBJECTIVES: We sought to evaluate differences in working time and subjective fatigue between the use of sliding sheets and non-assisted handling techniques for patient repositioning, in order to understand the factors preventing the use of sliding sheets among nurses. DESIGN: We conducted a comparative study with an experimental design. SETTINGS: The study was conducted in the nursing practice room at a university in Japan. PARTICIPANTS: We recruited 30 pairs of nurses and care receivers. All nurses were under 60 years old, with experience in lateral turning and repositioning in the process of changing diapers in clinical settings. Those with a previous or current medical history of low back pain were excluded. Care receivers were older adults (65-80 years old). We excluded adults with bedsores, body mass index values >30, or restricted joint motion due to femoral trochanteric fracture or compression fracture. Thus, 27 pairs were included in the final analysis. METHODS: The care receivers were instructed to behave as if they were bedridden patients with no limb movement, and as if they had contracture and difficulty communicating. Nurses repositioned the patient using three techniques assigned as interventions in random order: repositioning by one person using a sliding sheet (Sheet), repositioning by two people without a sliding sheet (Double), and repositioning by one person without a sliding sheet (Single). Working time was the primary endpoint for comparative analysis among the three technique conditions. RESULTS: The results revealed that the Sheet technique required significantly more time than the non-assisted techniques. However, when total staff time was taken into consideration, the Sheet technique outperformed the Double technique. Moreover, the Sheet technique was associated with significantly lower levels of subjective fatigue, compared with the Double technique. CONCLUSIONS: The use of a sliding sheet can substantially reduce caregiver burden when performing patient repositioning, and requires less staff time than manual techniques involving more than one caregiver.

T2 relaxation times of the retrodiscal tissue in patients with temporomandibular joint disorders and in healthy volunteers: a comparative study.

OBJECTIVE: The aims of this study were to compare the temporomandibular joint (TMJ) retrodiscal tissue T2 relaxation times between patients with temporomandibular disorders (TMDs) and asymptomatic volunteers and to assess the diagnostic potential of this approach. STUDY DESIGN: Patients with TMD (n = 173) and asymptomatic volunteers (n = 17) were examined by using a 1.5-T magnetic resonance scanner. The imaging protocol consisted of oblique sagittal, T2-weighted, 8-echo fast spin echo sequences in the closed mouth position. Retrodiscal tissue T2 relaxation times were obtained. Additionally, disc location and reduction, disc configuration, joint effusion, osteoarthritis, and bone edema or osteonecrosis were classified using MRI scans. The T2 relaxation times of each group were statistically compared. RESULTS: Retrodiscal tissue T2 relaxation times were significantly longer in patient groups than in asymptomatic volunteers (P < .01). T2 relaxation times were significantly longer in all of the morphologic categories. The most important variables affecting retrodiscal tissue T2 relaxation times were disc configuration, joint effusion, and osteoarthritis. CONCLUSIONS: Retrodiscal tissue T2 relaxation times of patients with TMD were significantly longer than those of healthy volunteers. This finding may lead to the development of a diagnostic marker to aid in the early detection of TMDs.

Evaluation of mouthpiece fixation devices for head and neck radiotherapy patients fabricated in PolyJet photopolymer by a 3D printer.

PURPOSE: The purpose of our study was to evaluate the usefulness of a biocompatible class VI resin PolyJet photopolymer Objet MED610 (MED610)-made mouthpiece fabricated using a 3D printer as a fixation device for head and neck radiotherapy patients. METHODS: Five mouthpieces made of GC Exafine putty type (GCEP) were fabricated from five dry skull bones. After computed tomography reconstruction of the GCEP-made mouthpiece and its surface extraction, the MED610-made mouthpieces were replicated. The sizes of the GCEP and MED610 mouthpieces were measured with a vernier caliper in width, length, and height, respectively. The volumes of these mouthpieces were measured by Archimedes' principle using pure water. For dose evaluation, the GCEP and MED610 mouthpieces were placed in the same part of a water phantom, and a 4-MV X-ray beam was located at the left maxillary gingiva, buccal mucosa, and oral floor. The dose for the planning target volume (PTV) was evaluated. RESULTS: The differences in the mean size and volume between the GCEP and MED610 mouthpieces were 0.03 mm and 0.21 cm3, respectively. Compared with the conventional GCEP mouthpiece, the dose absorption in the MED610 mouthpiece was closer to that in only water. When the mouthpiece was within the PTV margin, the minimum coverage dose at 95% of the PTV increased by 2.4% in the maxillary gingiva and by 3.6% in the buccal mucosa. CONCLUSION: A 3D printer can construct a mouthpiece accurately. The MED610 mouthpiece is suitable for use in dosimetry in head and neck radiotherapy.

Effectiveness of the periodically rotated overlapping parallel lines with enhanced reconstruction (PROPELLER) technique for reducing motion artifacts caused by mandibular movements on fat-suppressed T2-weighted magnetic resonance (MR) images.

PURPOSE: To compare a fat-suppressed T2-weighted periodically rotated overlapping parallel lines with enhanced reconstruction (T2W-PROPELLER) sequence with a fat-suppressed T2-weighted fast spin-echo (T2W-FSE) sequence in the oral and maxillofacial regions for the evaluation of the presence of motion artifacts caused by mandibular movements. METHODS: Fifty-six healthy adult volunteers were examined in a closed mouth position and then with three different rhythmical mandibular movements throughout MR scanning: open-close movement (movement 1), lateral movement (movement 2) and open-close and lateral movement (movement 3). All subjects were scanned first with fat-suppressed T2W-FSE and then with fat-suppressed T2W-PROPELLER while performing the same movements. Motion artifacts, including ghosting or pulsation artifacts, streak artifacts, susceptibility artifacts and the overall image quality were independently evaluated by two oral and maxillofacial radiologists using a five-point scale. The score graded by the two observers was averaged. RESULTS: The inter-observer agreement was almost perfect for all evaluated items (κ ≥ 0.81). The T2W-PROPELLER images showed significantly fewer ghosting artifacts than T2W-FSE images in subjects performing the mandibular movements throughout MR scanning (P < .001). T2W-PROPELLER images also showed significantly fewer pulsation artifacts than T2W-FSE images, regardless of the performance of a movement, throughout MR scanning (P < .001). Finally, the T2W-PROPELLER images showed a significantly better overall image quality than T2W-FSE images in subjects performing movements 2 or 3 throughout MR scanning (P < .001). CONCLUSION: The PROPELLER technique was found to be effective in reducing the motion artifacts caused by mandibular movements on fat-suppressed T2W MR images in the oral and maxillofacial regions.

How long should local warming for venodilation be used for peripheral intravenous cannulation? A prospective observational study.

BACKGROUND: Local warming is one of the most common venodilation techniques for achieving peripheral intravenous cannulation, but the time of application is unclear. OBJECTIVE: To compare the effectiveness of local warming applied for 5, 10, and 15min. DESIGN: A prospective, observational study. SETTING: A university in Japan. PARTICIPANTS: In total, 40 healthy female volunteers aged 20-45 years were recruited via e-mail. METHODS: Participants received 15min of local warming with a warmed heat pack (40±2°C). The primary outcome was the cross-sectional area of the target vein at 5, 10, and 15min of warming, which was measured after the intervention by blinded review using ultrasound. Secondary outcomes included forearm target site temperature at 5, 10, and 15min of local warming, which was measured with a temperature sensor and handheld thermometer. RESULTS: Compared to outcomes before local warming, vein cross-sectional area at 5, 10, and 15min of warming significantly (p <0.001) increased by 2.8, 2.9, and 2.3mm2. The target site temperature increased by 6.9°C, 6.4°C, and 6.0°C, respectively. However, no significant differences were found in cross-sectional area among the time points of 5, 10, and 15min of local warming. The target site temperature at 15min of local warming was significantly (p < 0.001) different than that at 5 and 10min. No adverse events occurred with local warming. CONCLUSION: Compared with outcomes before local warming, vein size after warming for 5, 10, and 15min was significantly larger. No significant differences were found in vein size among the time points of 5, 10, and 15min of local warming. Our result demonstrated the effectiveness of shorter-duration (5min) local warming for inducing venodilation for peripheral intravenous cannulation.

Does CBCT alter the diagnostic thinking efficacy, management and prognosis of patients with suspected Stage 0 medication-related osteonecrosis of the jaws?

OBJECTIVES: To evaluate the impact of cone beam CT (CBCT) in the diagnostic thinking efficacy, management and prognosis of patients with suspected Stage 0 medication-related osteonecrosis of the jaw (MRONJ). METHODS: For 15 patients with suspected Stage 0 MRONJ, clinical photographs, a panoramic radiograph and selected CBCT sections were identified. 13 oral surgeons reviewed the material and answered 10 questions in two different sessions. First session included clinical photographs and panoramic radiographs, while second session also included CBCT images. Questions (Qs) referred to dental disease and bone abnormalities (Qs 1, 2 and 3), differential diagnosis (Qs 4 and 5), patient management (Qs 6 and 7) and prognosis (Qs 8 and 9). Q 10 queried indication (first session) and usefulness (second session) of CBCT images. RESULTS: Qs 2, 3, 5, 7 and 9 scores increased between sessions, with statistical differences for Qs 2, 3, 5 and 7 (<0.05). Patients 2, 8 and 11 showed a significant increase in the average score of all Qs between sessions, while scores for patient 10 nearly reached statistical significance (p = 0.055). For Q 10, 57.4% of answers reported that CBCT was needed (first session) and was beneficial (second session). CONCLUSIONS: CBCT had a significant impact in differential diagnosis and management of patients with suspected Stage 0 MRONJ.

Changes in the Submandibular Gland in Patients with Head and Neck Cancer After Radiation Therapy: A Preliminary Study.

AIM: The purpose of this study was to assess the impairment of the submandibular gland, in terms of changes in volume by computed tomography (CT) and CT value, which was the mean pixel value at a region of interest, in a group of patients with head and neck cancer treated with radiation therapy (RT). PATIENTS AND METHODS: Eleven patients treated with RT, where the effective radiation dose to the submandibular gland was known, were included in the study. CT scanning was performed both before and after RT. The average follow-up period after RT was 555 days (range=107-1231 days). RESULTS: The mean volume of the submandibular gland decreased by around 38% (p<0.001) compared to the pre-treatment average until 600 days after RT. The mean CT value of the submandibular gland decreased until 200 days after RT (p<0.05). CONCLUSION: Both volume and CT value of the submandibular gland showed signs of impairment of the gland during the first several months after RT for head and neck cancer.

Tourniquet application after local forearm warming to improve venodilation for peripheral intravenous cannulation in young and middle-aged adults: A single-blind prospective randomized controlled trial.

BACKGROUND: Local forearm warming before tourniquet application is often used to promote venodilation for peripheral intravenous cannulation; however, few studies have compared the effect of tourniquet application with and without local warming on vein size. OBJECTIVE: To evaluate the effectiveness of tourniquet application after local forearm warming with that of tourniquet application alone in young and middle-aged adults. DESIGN: A single-blind, prospective, parallel group, randomized controlled trial. SETTING: A national university in Japan. PARTICIPANTS: Seventy-two volunteers aged 20-64 years. METHODS: Participants were randomly allocated to one of two groups: tourniquet application for 30s after forearm application of a heat pack warmed to 40°C±2°C for 15min (active warming group; n=36) or tourniquet application for 30s after applying a non-warmed heat pack for 15min (passive warming group; n=36). The primary outcomes were vein cross-sectional area on the forearm, measured after the intervention by blinded research assistants using ultrasound. Secondary outcomes were shortest diameter, and longest diameter of vein on the forearm, forearm skin temperature, body temperature, pulse, systolic blood pressure, and diastolic blood pressure. All outcomes were assessed at the same site before and immediately after the intervention, once per participant. RESULTS: Vein cross-sectional area, shortest vein diameter, and longest vein diameter were significantly increased in the active warming group compared with the passive warming group (p <0.01). Tourniquet application after local warming was superior to tourniquet application alone in increasing vein cross-sectional, shortest diameter, and longest diameter (between-group differences of 2.2mm2, 0.5mm, and 0.5mm, respectively), and in raising skin temperature (between-group difference: 5.2°C). However, there were no significant differences in body temperature, pulse, or systolic or diastolic blood pressure between the groups. There were no adverse events associated with either intervention. CONCLUSION: Tourniquet application after local warming was associated with increased forearm vein size when compared with tourniquet application alone, and was demonstrated as being safe. Thus, with demonstrable effects on vein size, we recommend local warming before tourniquet application as a safe and effective technique for improving venodilation.

Duration of Venodilation for Peripheral Intravenous Cannulation, as Induced by a Thermal Stimulus on the Forearm.

BACKGROUND: Application of a thermal stimulus is a common procedure used to promote venodilation for peripheral intravenous cannulation (PIVC); however, the effects of thermal stimulation on the duration of venodilation and skin temperature of the forearm are unclear. AIM: To investigate the duration of venodilation induced by a thermal stimulus on the forearm. METHOD: Healthy female adults ( N = 40) from Japan participated in this study from November to December 2013. A heat pack was warmed to 40°C ± 2°C and placed over the forearm for 15 min. Vein diameter was measured via ultrasound and skin temperature via temperature sensor at six time points: before application of the thermal stimulus and at 1-min intervals for 5 min upon removal of the thermal stimulus. The main outcomes were vein diameter, proportional change in vein diameter, and skin temperature. We calculated proportional change in vein diameter after application of the thermal stimulus using vein diameter before the thermal stimulus to represent 100%. RESULTS: Compared with vein diameter before thermal stimulus, the diameter at each time point after thermal stimulus was significantly increased ( p < .05) as were proportional change in vein diameter ( p < .05) and skin temperature. CONCLUSION: A thermal stimulus of 40°C ± 2°C on the forearm dilated veins significantly for PIVC, and the effect persisted for at least 5 min.

Perceptions of nurses in Japan toward their patients' expectations of care: A qualitative study.

OBJECTIVES: This study aimed to investigate ideal nurse involvement based on the expectations of patients. Data on conflicts between nurses and patients were obtained. The patient situation involved standard nursing treatment, rather than acute phase or palliative care. METHODS: Questionnaires were distributed among senior nurses attending a series of trainings in 2012 and 2013. The nurses were requested to return their completed questionnaires within two weeks. We ensured the effectiveness of the interview process to obtain accurate answers.The sample comprised 240 head nurses and assistant head nurses who were asked to respond anonymously to 57 questions about non-acute (stable) psychiatric or physical nurse-patient scenarios. Qualitative data analysis was conducted using these responses. RESULTS: We received 41 completed responses (response rate = 17.1%). The expectations of patients and their families were reflected in five categories, namely, inference, empathic understanding, listening attitude, individual treatment, and reliable skills and explanations. Inference was independently categorized as a particularly strong characteristic of Japanese patients' expectations. CONCLUSIONS: Nursing care in situations where conflicts or misunderstandings may arise can be improved by encouraging nurses to be attentive to the moods, feelings, and expectations of patients and their families. The findings from this study can improve the quality of Japanese nursing care with regard to sensing (inferring) and reacting to the expectations of patients.

Evaluation of the scatter doses in the direction of the buccal mucosa from dental metals.

The presence of dental metals creates radiation dose perturbation due to scattered radiation during radiation therapy for the head and neck region. The purpose of our study was to compare the scatter doses resulting from various dental metals in the direction of the buccal mucosa among a single-field technique, three-dimensional conformal radiation therapy (3D CRT), and intensity-modulated radiation therapy (IMRT) during radiation therapy for the head and neck region. We used nine metal cubes with 10 mm sides, which were placed inside a water phantom. The scatter doses from the cubes in the direction of the buccal mucosa were measured using radiochromic films. The films were placed perpendicularly to the surface of the cubes. The phantom was irradiated with a 4 MV photon energy by a linear accelerator for all techniques. In the single-field technique, the scatter doses from dental metals showed 3.7%-19.3% dose increases, and gold showed the largest dose increase. In 3D CRT, the scatter doses from dental metals showed 1.4%-6.9% dose increases, which were within the measurement uncertainty (except for gold). In IMRT, the scatter doses from dental metals showed only 1.4%-4.3% dose increases, which were all within the measurement uncertainty. During radiation therapy for the head and neck region, the scatter doses from the tested dental metals in the direction of the buccal mucosa in 3D CRT or IMRT were lower than those using the single-field technique. However, there were no differences between the scatter doses resulting from particular dental metals in the direction of the buccal mucosa in 3D CRT and those in IMRT, except for gold.

Influence of an object's z-axis location and location on the axial plane on the voxel value representation and uniformity in cone beam computed tomography.

OBJECTIVE: This study aimed to determine the influence of an object's z-axis location and location on the axial plane on the voxel values in cone beam computed tomography. STUDY DESIGN: The CTP401 and CTP486 of the Catphan 500 phantom were scanned with an Alphard-3030 at 6 locations in the z-axis. RESULTS: In CTP401, the voxel values of 3 inserts showed the lowest values when the center of the radiation field corresponded to under 2 or 4 cm of the z-axis center of CTP401. In CTP486, the voxel values showed the lowest values when the center of the radiation field corresponded to under 2 or 4 cm of the z-axis center of CTP486. On the same axial plane, the voxel values at the center showed significantly lower values than the off-center locations (P = .002). CONCLUSIONS: The voxel values in the Alphard-3030 changed based on the z-axis location of the radiation field and were nonuniform on the same axial plane.