[Diffuse aspiration bronchiolitis in an elderly woman].

A 74-year-old woman was admitted to the hospital because of persistent nocturnal coughing and abnormal shadows on chest x-ray films. The films showed cavities in the right upper lobe and small nodular shadows in the right upper, lower, and left upper lung fields. Examination of a specimen obtained by transbronchial lung biopsy showed nonspecific inflammatory changes. An open-lung biopsy was done. Histopathological examination showed evidence of diffuse aspiration bronchiolitis and actinomyces. Actinomyces is a member of the endogenous flora of the oral mucous membranes. Our diagnosis was diffuse aspiration bronchiolitis caused by micro-aspiration of oro-pharyngeal secretions during sleep.

Intraoperative measurements of auditory-evoked potentials in three patients with acoustic neuroma.

Auditory brainstem responses (ABRs), electrocochleograms and the evoked potentials from the internal auditory canal were recorded simultaneously in 3 acoustic neuroma (AN) patients. The neural conduction in the internal auditory canal was examined by recording the compound action potentials of the cochlear nerve. In an AN patient with wave I only in the ABR, the neural conduction of the excitement in the cochlear nerve was blocked within the internal auditory canal. In 2 AN patients with elongated interpeak latency differences between waves I and V in ABRs, the neural conduction velocity of the cochlear nerve was lower than that of normal subjects. These results provide neurophysiological evidence that low neural conduction velocity in the cochlear nerve results in the abnormal ABR.

Usefulness of auditory brainstem responses at high stimulus rates in the diagnosis of acoustic neuroma.

The effects of the stimulus rate on the auditory brainstem responses (ABRs) of acoustic neuroma (AN) patients were studied. Ninety-decibel click stimuli at a normal hearing level were delivered at stimulus rates of 9.5, 20, 40 and 90 Hz, and ABRs were recorded of 40 AN patients (40 ears) at each stimulus rate. Subjects with normal hearing (42 ears) and patients with sensorineural hearing loss (30 ears) were also studied to obtain normative data. The following two parameters were examined: the interpeak latency difference between wave I and wave V (IPL I-V) at each stimulus rate, and the increase in IPL I-V (delta IPL I-V) when the stimulus rate was increased from 9.5 Hz. AN patients showed significantly larger values for both parameters at all stimulus rates compared to those of the control groups. Among 6 AN patients with normal ABRs at 9.5 Hz, 5 showed abnormal IPL I-V or abnormal delta IPL I-V at 90 Hz, when the upper normal limits of both parameters were defined as the mean plus 2 SD of the group with normal hearing. These results suggest that recording ABR at high stimulus rates provides valuable information for detecting AN patients with normal ABRs.

Schwannoma of the posterior pharyngeal wall: a case report.

Schwannoma arising in the posterior pharyngeal wall is rare. We report on a 60-year-old man who complained of discomfort in his pharynx, from whom a tumour was excised via an intraoral approach. No recurrence was seen after an 11-year follow-up. The nerve origin of the tumour is most likely to be the peripharyngeal plexus. This is the third such case reported.

Pleomorphic adenoma of the external auditory canal: a case report and review of the literature.

Pleomorphic adenoma arising in the external auditory canal is rare. We report the case of a 38-year-old man. To better grasp the clinical features and natural history of this uncommon tumour, we also reviewed the worldwide literature and found 24 similar cases, which we analysed together with our own.

[Three cases of postoperative laryngopharyngeal edema following nonsimultaneous bilateral radical neck dissection].

Three cases of postoperative laryngopharyngeal edema following nonsimultaneous radical neck dissection are presented. Case 1 was a 65-year-old male with tongue cancer and left cervical lymph node metastases. Hemiglossectomy, reconstruction of the floor of the mouth with a free rectus abdominis flap, and left radical neck dissection had been performed. Postoperatively, the tongue and left upper neck were irradiated. Seven months later, right cervical lymph node metastases were observed. Right radical neck dissection was performed, and immediately after extubation, upper airway stenosis due to severe laryngopharyngeal edema occurred. Emergent tracheostomy saved his life. Case 2 was a 55-year-old female with tongue cancer and right cervical lymph node metastases. Radium needles had been implanted in the tongue, and right radical neck dissection was performed. Three months later, left cervical lymph node metastases were found. Left radical neck dissection was performed and, as in Case 1, upper airway stenosis revealed immediately after extubation. Since the situation was anticipated, an immediate tracheostomy was done. Case 3 was a 43-year-old male with laryngeal cancer and left cervical lymph node metastasis. Irradiation of the larynx and the bilateral upper neck followed by left radical neck dissection and partial laryngohypopharyngectomy had been performed. Five years later, right cervical lymph node metastasis was observed. Right radical neck dissection was performed, and laryngoscopic examination before extubation revealed severe laryngopharyngeal edema. In this case, tracheostomy was performed before extubation. To our knowledge, there have been only five cases of postoperative laryngopharyngeal edema, following nonsimultaneous radical neck dissection, reported in the literature.

[The volume ratio between squamosal and petrosal air cells divided by Körner's septum].

Pneumatized air cells of the temporal bone are embryologically divided into two portions; the squamosal portion and the petrosal portion. These two portions are anatomically separated by the petrosquamous fissure and petrosquamous lamina, the so-called Körner's septum. In this study, the volumes of the two portions were measured with Target Imaging CT in 5 normal ears (3 subjects) with a clearly recognizable Körner's septum. The combined volume of the two portions, in all CT slices, was also measured. The squamosal portion occupied 32.7% of the total air cell volume, on average, and the petrosal portion was 67.3%. A positive correlation was observed between the total air cell volume of the temporal bone and the volume ratio of the petrosal portion. When the volume of each part was examined according to the CT slice level, from high to low, the maximum volume of the squamosal portion was at the slice level of the epitympanic cavity. The volume of the petrosal portion was prominent at the slice level of the epitympanic cavity and the upper antrum. These results that the petrosal portion plays a more important role than the squamosal portion in pneumatization of the temporal bone. This analysis with Target Imaging CT provides useful information for understanding the middle ear pathology resulting from poor pneumatization of the temporal bone.

[Area and volume relationship of temporal bone air cells].

The area and volume of the air cell system of fifty normal temporal bones were investigated. The area on a plain X-ray, Sonnenkalb projection, was measured by a planimetric method and a rectangular dimensional method by Imai in 1978. The volumes of the temporal bone air cells on high-resolution CT were calculated separately as partial volumes divided in all CT planes. The sum of the partial volumes was calculated as the total volume of the air cells. The relationship between the area and the total volume of the air cell system was analyzed statistically. The ratio of the partial spatial volume, e.g. the tympanic cavity and the apical air space, to the total volume of the temporal bone air cells was also calculated. The results were as follows: 1) The relationship between the two measurements were as follows: planimetric method, Y = 0.901X - 2.26 (r = 0.885), and rectangular dimensional method, Y = 0.542X - 2.57 (r = 0.876). 2) The ratio of the volume of the tympanic cavity to the total volume of the air cell system was 6.74 +/- 4.07%. The larger the total volume, the smaller the ratio. 3) The ratio of the apical space was 7.09 +/- 4.98%, and the larger the total volume, the larger the ratio.

[Bone mineral density of the internal auditory meatus with acoustic neuroma].

The bone mineral density of the internal auditory meatus was investigated by means of quantitative computed tomography (QCT) in 12 patients with acoustic tumor. Investigated portions of the internal auditory meatus were the anterior and posterior porus and the anterior and posterior fundus. The bony vestibule and cortical bone of the mastoid cavity were also investigated. The bone density values (calcium carbonate equivalent value) for each portion were analyzed statistically. Another investigation by CT program "Profile" revealed changes in CT values along the posterior wall of the internal auditory meatus, and the results were compared with that of the QCT. The following results were obtained: 1) The highest calcium carbonate equivalent value was found in the posterior fundus, the lowest in the anterior porus. There were significant differences between the bilateral fundus and porus values. 2) There was a marked difference only in the anterior fundus of the abnormal side in comparison with the normal side, while differences in the other 5 portions were not statistically significant. 3) There were no significant differences in any of the portions between cases of superior vestibular nerve origin and those of inferior vestibular nerve origin. 4) In Profile, the CT values increased gradually from the porus to the fundus on both sides. A dip formation, indicating a lower CT value, was found between the porus and fundus in many cases. It was suggested that this dip formation was influenced by pneumatization of the posterior wall of the internal auditory meatus.

[Pneumatization of the petrous apex].

Pneumatization of the petrous apex was investigated in 226 subjects without middle ear disease by means of target imaging CT. The degree of pneumatization of all subjects was 32.7% (148/452 ears), but no difference in degree was revealed with distinction of bilateral ears or between sexes. In 148 ears with pneumatization of the petrous apex, a higher degree of pneumatization was found in larger mastoid cavities, suggesting that pneumatization of the petrous apex correlates with pneumatized air cells in other parts of the temporal bone. Pneumatization of all parts of the petrous apex was found in about 40% (58/148 ears), and of some parts in about 60% (90/148 ears). In the latter cases, pneumatized air cells were more often found in the lower portions of the CT slices than in the higher ones. These results indicate that pneumatization of the petrous apex must be taken into consideration in studies measuring the gas composition and volume of the middle ear.

[Relationship between external auditory canal temperature and caloric nystagmus--the problem with the ordinary cold-warm caloric test].

The cold-warm caloric test is performed with water irrigation, using a hot temperature of 44 degrees C and a cold temperature of 30 degrees C, which are thermally equidistant from the body temperature 37 degrees C. However, the 30 degrees C irrigation nearly always produces a stronger nystagmic response than that of the 44 degrees C stimulation. The purpose of this study is to investigate the difference in nystagmic response between cold and hot stimulation. The achieved hot (44 degrees C) and cold (30 degrees C) water samples were prepared, and irrigation was with a disposable plastic syringe. Temperature changes in the external auditory canal were monitored by tympanic thermometry during the cold-warm caloric test. Maximal slow phase velocity and the duration of induced nystagmus were recorded on an electro-nystagmograph. The following conclusions were drawn; 1) The average normal external auditory canal temperature was 36.8 degrees C, and there was no side difference between the right and left ears. External canal temperature was higher than that of the axilla. 2) When 20 ml of 30 degrees C water was instilled the temperature change in the external canal was larger than that in response to the 44 degrees C water and the maximal slow phase velocity of nystagmus for cold stimulation was stronger than that for hot. However, the duration of nystagmus for the cold was not significantly longer than that of the hot stimulation.

[Bone mineral density of the internal auditory meatus by quantitative computed tomography].

The bone mineral density of the internal auditory meatus was investigated by means of quantitative computed tomography in 20 normal subjects (40 ears). Investigated portions of the internal auditory meatus were the porus anterior and posterior and the fundus anterior and posterior. Two other portions of the ear, the bony vestibule and lateral wall of the mastoid, were also investigated. The bone density values (calcium carbonate equivalent value) for each portion were analyzed statistically. The following results were obtained: 1) There was no significant difference between the right and left values in any portion. 2) The highest mean value was found in the fundus posterior, the lowest in the porus anterior. There was a significant difference between the values of the fundus and porus. Bone hardness generally correlates with bone density. Thus, the bone hardness of the porus of the internal auditory meatus was appraised to be lower than that of the fundus. These results suggest that this is one of the factors promoting enlargement of the internal auditory meatus in acoustic neuroma.

[Distribution of motor nuclei in feline ventral neck muscles].

The distribution of motor nuclei in feline neck muscles at the level of the third and fourth cervical vertebrae of spinal cord was investigated, using retrograde labelling with horseradish peroxidase (HRP). HRP powder was directly injected into the cut ends of the peripheral nerves innervating each muscle. Investigated muscles in this thesis included 5 ventral muscles: Levator scapulae m.(LS), Levator scapulae ventralis m.(LSV), Longus colli m.(LC), Longus capitis m. (LCP), Intertransversarius ventralis m.(ITV). Two dorsal muscles were also examined; Splenius m.(SP) and Biventer m.(BV). The findings in retrogradely labelled motoneurons of each muscle were as follows: 1) LS and LSV (V1 ventral muscles) Labelled motoneurons were observed at the lateral border of the ventral horn, and the distribution of LSV was more dorsal than that of LS. Their cellular distributions varied from the rostral end of the third cervical segment dorsolaterally to the caudal end of the fourth cervical segment ventromedially. 2) LC, LCP and ITV (V2 ventral muscles) Labelled motoneurons were observed at the medial border of the ventral horn. The distribution of LCP was more dorsal than that of LC and ITV, but their cellular distributions were largely intermingled. The variation in cellular distribution, which was observed in V1 ventral muscles, was not recognized in this muscle group. 3) SP and BV (D1 and D2 dorsal muscles) Labelled motoneurons were observed at the apex of the ventral horn, referred to as the ventromedial nucleus by Rexed. The distribution of SP was more dorsolateral than that of BV, and the changes in cellular distribution seen in V1 ventral muscles were also observed in these muscles. Some unorganized labelled cells were found at the medial border of the ipsilateral ventral horn, anterior funiculus, anterior commissure and contralateral ventral horn. These irregularly positioned cells were not found in the staining of the ventral muscles. Organized distributions of motoneurons in the ventral horn corresponded respectively to the classification of trunk muscles, as described by Nishi (1938) in accordance with the peripheral innervation of each trunk muscle. These results indicate that the pattern of peripheral innervation reflects the spinal level, and provides important information for electrophysiological analysis of the neural network between the central and peripheral nervous systems.

[Difference between horizontal enlargement and vertical enlargement of the internal auditory meatus in acoustic neuroma].

Twenty-one patients with acoustic neuroma were investigated. The vertical diameter of the internal auditory meatus was measured by polytomography, the horizontal by target imaging CT. The ratio of the abnormal side to the normal side was calculated in each dimension. Two dimensional ratios were compared with each other in order to investigate the difference between horizontal and vertical enlargement of the internal auditory meatus. The results were as follows: 1) Horizontal enlargement of the internal auditory meatus was greater than that of the vertical one in 15 cases (75%). Vertical enlargement was greater in 6 cases but the difference between the two dimensions was not significant. 2) With horizontal enlargement, the posterior wall of the internal auditory meatus was more extended or destroyed than that of anterior wall. 3) With enlargement of the posterior wall, the bony eminence forming the inner side of the porus was predominantly extended or destroyed in every case.

[Reconstruction of hypopharynx and cervical esophagus using a free jejunal graft].

Forty-four patients with cancer in the hypopharynx and cervical esophagus underwent pharyngoesophageal reconstruction with a free jejunal graft after total removal of a tumor combined with resection of the circumferential tissues. The graft survival rate was 93.2% (41 of 44). Postoperative complications occurred in 16 patients (36.4%), which included postoperative death in one (2.3%), graft necrosis in 3 (6.8%), fistula formation in 4 (9.1%) and graft stricture in 3 (6.8%). All 3 cases of graft necrosis underwent successfully reimplantation. The mean interval time was 20.9 days until oral intake was possible. Thirty-two of 42 patients (76.2%) were able to take usual food. Esophageal speech was limited in the selected cases by this procedure. A cumulative survival rate of 5 years was 40.6% in this series. This method of reconstruction should be advocated as one of relatively safe and reliable procedures for patients with hypopharyngeal and cervical esophageal cancer.