Satoshi Yoshioka

There are many methods and types of equipment for measuring the nasal airway, but there is no consensus regarding the results of various clinical studies on nasal obstruction. In this review, we discuss the two major methods of objectively assessing the nasal airway: rhinomanometry and acoustic rhinometry. The Japanese standard of rhinomanometry in Japanese adults and children was established by the Japanese Standardization Committee on Rhinomanometry in 2001 and 2018, respectively. However, the International Standardization Committee has proposed different standards because of differences in race, equipment, and social health insurance systems. The standardization of acoustic rhinometry in Japanese adults is making progress in several Japanese institutes, but the international standardization of acoustic rhinometry has not yet begun. Rhinomanometry is the physiological expression of nasal airway breathing, whereas acoustic rhinometry is the anatomic expression. In this review, we introduce the history and methods of the objective assessment of nasal patency and the physiological and pathological issues regarding nasal obstruction.

<title>Abstract</title> Background The aims of this study were to perform a four-dimensional assessment of velopharyngeal closure function in pediatric patients with cleft palate using 320-row area detector computed tomography (CT), and to estimate the organ-absorbed doses using Monte Carlo simulation. Methods We evaluated CT image data obtained between July 2018 and August 2019 from five pediatric patients with cleft palate (four boys and one girl; age range, 4–7 years) at Fujita Health University Hospital. The presence of velopharyngeal insufficiency (VPI), patterns of velopharyngeal closure (VPC), and cross-sectional area of VPI were evaluated. In addition, organ-absorbed doses were assumed in the Monte Carlo simulation. However, we did not perform statistical analysis because of the insufficient number of patients enrolled in this study. Results The existence of VPI and hypernasality were completely concordant. The VPC patterns were circular (two patients), circular with Passavant’s ridge (one patient), and unevaluable (two patients). The organ-absorbed doses were relatively lower than those in past reports. Conclusions Our method could be an alternative for patients who refuse the conventional nasopharyngoscopic evaluation.

<p>Despite apparent ability of computed tomography (CT) in clinical practice, otology, which requires diagnosis and treatment of variaous diseases involve very small areas and sometimes entails a limitation on the performance of CT in depicting lesions located in such areas. Recently, ultra-high-resolution (UHR) CT, which can provide images at dramatically higher spatial resolution than ever before, has been developed and has become commercially available. UHRCT has a pixel size (0.25×0.25 mm) twice comparing dense in both vertical and horizontal directions as conventional high-resolution (CHR) CT and the maximum spatial resolution of 0.15mm or less in the axial direction. The maximum size image is 2048×2048 pixels. Here, we report our experience of the early stage development of UHRCT in the field of otology.</p><p>We performed UHRCT scan in otology patients and compared the images obtained from UHRCT with those obtained from CHRCT. Spatial resolution in UHRCT images was obviously improved. Tiny structures, such as the chorda tympani and ossicles, and small pathological changes caused by the progression of otitis media, etc. were clearly depicted. Due to an increase in the partial volume effect, improvements such as the performance of UHRCT in depicting soft-tissue lesions or lesions adjacent to the bone, were considered to be difficult to depict at CHRCT.</p><p>The tiny structures which had been indistinct before, became clearly visible due to UHRCT, indicating the possibility of providing important information for clinical practice. However, because the issues include the necessity of building infrastructure (including display) and a powerful computer system enough to save and handle huge volume of data, it is necessary to examine the further usage of UHRCT in the future.</p>

中耳から補聴器のイヤモールド印象材を手術的に除去した2症例を報告した。症例1は持続的な耳漏を主訴とする78歳男性。当初は慢性中耳炎と診断され保存的療法を受けていたが耳漏の改善は見られなかった。その後の検査で鼓室に異物を認め、その異物の素材分析により印象材であることが判明した。その後の問診で患者は約15年前に補聴器のイヤモールドを調製したことを思い出し、鼓室形成術を受けて異物除去に成功した。症例2はcanal wall down型鼓室形成術を受けた84歳女性で、左耳に印象材を注入されたが、その除去を受けていなかった。検査で乳突腔に埋入した印象材を認め、耳介後部の切開による異物を摘出した。いずれの症例でも、患者の病歴の問診、鼓膜の十分な検査、術後の補聴器フィッティング関連のリスクへの注意、ならびに不注意による補聴器フィッティング時の印象材押し込みの回避が重要になると考えられた。

<p>Determining the correspondence between points on the area–distance curve derived from acoustic rhinometry and the anatomical landmarks in the nasal and nasopharyngeal airway is important for the clinical evaluation of obstructive sleep apnea in children. In this study, area–distance curves derived from acoustic rhinometry (SER-2000; Rhino Metrics Co., Ltd., Denmark) were measured in a life-size, artificial, soft-silicon, upper-airway model of a healthy 5-year-old child (Koken Co., Ltd., Japan). We created obstacles in both the nasal cavity and nasopharynx with clay, simulating various grades of adenoid hypertorophy. On the area–distance curve, the anterior portion of the inferior turbinate corresponded to the region between the second notch and third peak, the posterior end of the nasal septum corresponded to the third peak, and the adenoid corresponded to the region from immediately after the third peak to 8 mm posterior to the fourth notch. The measured adenoidal volume matched the actual volume of the simulated adenoid; however, the measured airway volume of the nasopharynx according to acoustic rhinometry was far greater than the actual volume of the model. We conclude that the landmarks identified on the area–distance curve and the changes in adenoid volume measured with acoustic rhinometry have potential clinical application. However, acoustic rhinometry measurements of nasopharynx airway volume could be improved.</p>

<p>We report a case of bronchial foreign body which remained lodged over a long term. The patient was an infant boy aged 1 year and four months. He was brought to our hospital for a cough that had persisted for four months. He had been treated for pneumonia, but did not heal. By CT we diagnosed a bronchial foreign body in the chest and removed it by bronchoscope. The foreign body was cellophane tape. We believe that diagnosis of a bronchial foreign body was delayed because of the X-ray permeability of this particular foreign body, combined with failure of the doctor undertaking the initial medical examination to suspect a bronchial foreign body.</p>

<p>We presented our experienced, 44 year-old female, rare and severe case with lingual tonsillitis and multiple cysts infection of epiglottis which was necessary for receiving the tracheostomy.</p><p>The urgent tracheostomy was very useful for the patient. Against the hypertrophy of lingual tonsils and multiple cysts of epiglottis, we adopted lingual tonsillectomy and total removal of epiglottic multiple cysts by using KTP laser equipment.</p><p>In conclusion, we, otolaryngologist, should be familiar with the surgical procedure of urgent tracheostomy and will recommend for using the KTP laser against lingual tonsillectomy, because of the effect of bleeding stoppage being high and the operability being good.</p>

Although modern multislice CT systems can quickly scan a wide range in fine detail, the high exposure dose and long examination time of CT studies are still important issues. CT is therefore generally considered to be unsuitable for screening. This is particularly true for pediatric patients, who are especially sensitive to radiation, and plain radiography is therefore frequently selected for examination of the temporal bone. We have developed an ultra-low-dose CT imaging method using a 320-row area detector CT (ADCT) scanner that may be suitable for screening for diseases of the ear even in pediatric patients.<BR>Temporal bone specimens were scanned with an ADCT scanner (Aquilion ONE^<TM>, Toshiba Medical Systems, Otawara, Japan) using various scan conditions. Image quality was evaluated, and the optimal scan conditions providing clinically acceptable images at the lowest possible exposure dose were identified. A human-body phantom was then scanned with ADCT using these scan conditions. Plain radiography using the Schu..ller method was also performed for the same phantom to acquire images of the temporal bones bilaterally. The CT and radiographic exposure doses were compared to assess the suitability of our ADCT method for screening.<BR>The gantry of the ADCT scanner includes an X-ray source unit and a detector (area detector) which is several times larger than that used in a conventional CT system. Three-dimensional data can be acquired over a wide range in a single high-speed rotation, making it possible to quickly obtain images in the same temporal phase.<BR>As the results, the optimal scan conditions were found to be tube voltage 100 kV, tube current 10 mA, and exposure time 1.5 s/rot. by 1 rotation. The CTDIVOL (standard dose) was 1.7 mGy, which is 0.7% of the usual value of 243.4 mGy. The maximum skin dose to the head in plain radiography of the temporal bones bilaterally was 2.12 mGy on average. The maximum skin dose to the external ear in CT scanning with the above conditions was 1.59 mGy on average, which was lower than that for the Sch&uuml;ller method. However, the dose in CT scanning was slightly higher at the front and rear.<BR>With our proposed CT imaging method, images are acquired in a very short time, three-dimensional image data is obtained, and the exposure dose is equal to or lower than that of plain radiography. This method is therefore expected to be a useful new tool for morphological screening examinations.