A case of palmoplantar lichen planus in a patient with congenital sensorineural deafness

We report a case of palmoplantar lichen planus in a 7-year-old Japanese girl with congenital deafness, who presented with erythematous eruptions and hyperkeratosis, with peeling and fissures on her soles, palms and digits. On histological examination of a skin biopsy from the lesion on her wrist, lichen planus was identified. Using computed tomography of the inner ears, bilateral cochlear dysplasia was found. The patient's DNA was sequenced; no sequence variants were detected in the GJB2 gene encoding connexin-26, but she had a missense mutation in SLC26A4 (solute carrier family 26, member 4). Mutations in SLC26A4 are known causes of hearing loss, but this is a novel mutation, which has not been reported previously. In addition, there have been no reports of cutaneous symptoms in previously reported patients with mutations in SLC26A4. To our knowledge, therefore, this is the first report of palmoplantar lichen planus associated with sensorineural deafness accompanied by a mutation in the SLC26A4 gene.

A case of bilateral middle-ear squamous cell carcinoma

Only eight cases of bilateral middle-ear squamous cell carcinoma (SCC) have been reported to date. We present the case of a 75-year-old male with bilateral middle-ear SCC and review the previously reported cases. The patient was diagnosed as having moderately-differentiated SCC in the left middle ear in February 1995 and well-differentiated SCC in the right middle ear in September 1997. He initially received radiation therapy with (60)Co pendulum (64 Gy) in the left ear and was subsequently treated by Liniac irradiation (50 Gy) in the right ear. He has now been followed up at our ENT clinic for 29 months without vertigo or facial nerve palsy since the second radiation therapy. Although he has a residual tumour in the right middle ear invading the middle cranial fossa dura, no sign of recurrence has been detected in the left ear.

Expression pattern of aquaporin water channels in the inner ear of the rat. The molecular basis for a water regulation system in the endolymphatic sac

Mammalian aquaporins constitute a family of so far 10 related water channel proteins which mediate osmotically driven water fluxes across the plasma membrane. Because regulation of the ionic composition and osmolality of inner ear fluids is of great functional significance, we investigated the expression patterns of aquaporins in five defined areas of the rat inner ear by RT-PCR. The tissues used were stria vascularis, endolymphatic sac, Reissner's membrane, vestibulum and organ of Corti. Aquaporin 1 transcripts were detected in all tissues and are probably constitutive. Aquaporin 5 was only expressed in the organ of Corti and in Reissner's membrane. We show that aquaporin 2, so far considered to be specific to the principal cells of the renal collecting duct, is expressed in the endolymphatic sac. Aquaporin 2 expression was not detected in any other inner ear region. The postnatal appearance of aquaporin 2 transcripts in the endolymphatic sac resembled that in the kidney, i.e. it increased postnatally until day 4. The full-length DNA for aquaporin 2 was cloned from cDNA of the endolymphatic sac. It had an irrelevant Ile54Thr mutation because it could be functionally expressed in Xenopus oocytes. Also exclusively in the endolymphatic sac of the inner ear, we detected transcripts for aquaporin isoforms 3 and 4 which are known to be expressed in the renal principal cells. In the kidney, aquaporin 2 regulation involves vasopressin-stimulated, cAMP-dependent phosphorylation of Ser256 of aquaporin 2 which is stored in cytosolic vesicles. These storage vesicles also contain a serpentine calcium/polycation-sensing receptor. Vesicle shuffling to the plasma membrane involves proteins such as vesicle-associated membrane protein VAMP2, syntaxin-4 and the small GTPase Rab3a. Using RT-PCR we were able to demonstrate the expression of all of these components. By analogy the data suggest that in the endolymphatic sac of the inner ear a system for cellular water permeability is in place which may share many similarities with that characterized in the principal cells of the renal collecting duct. These findings may have a number of interesting pharmacological implications which need to be addressed in future studies.

Expression pattern of adenylyl cyclase isoforms in the inner ear of the rat by RT-PCR and immunochemical localization of calcineurin in the organ of Corti

Most studies concerning adenylyl cyclases in the inner ear were carried out before the advent of molecular biology. In a PCR approach using cDNAs of six inner ear tissues (stria vascularis, endolymphatic sac, organ of Corti, vestibulum, cochlear and vestibular nerve) we found tissue specific expression of adenylyl cyclase isoforms. Adenylyl cyclases types 2 and 4 are predominant in the fluid controlling tissues, i.e. in the stria vascularis and endolymphatic sac. In the organ of Corti and vestibulum the Ca2+-modulated isoforms types 1, 6 and 9 were expressed. The regulation of adenylyl cyclase 9, which is the major isoform expressed in the organ of Corti, proceeds via the Ca2+-activated protein phosphatase 2B (calcineurin, PPP3). PCR with specific primers for calcineurin demonstrated its abundant expression in the organ of Corti. Using a monoclonal antibody we localized calcineurin immunochemically to the cochlear nerve, the nerve fibers and the inner hair cells. In the cochlear and vestibular nerves a characteristic neuronal expression pattern of adenylyl cyclase isoforms was observed, i.e. adenylyl cyclases types 2, 3 and 8. The functional consequences of the adenylyl cyclase expression pattern in the inner ear are discussed in conjunction with its unique sensory performance.

Expression of membrane-bound and cytosolic guanylyl cyclases in the rat inner ear

Membrane-bound guanylyl cyclases (GCs) are peptide hormone receptors whereas the cytosolic isoforms are receptors for nitric oxide. In the inner ear, the membrane-bound GCs may be involved in the regulation of fluid homeostasis and the cytosolic forms possibly play a role in signal processing and regulation of local blood flow. In this comprehensive study, we examined, qualitatively and quantitatively, the transcription pattern of all known GC isoforms in the inner ear from rat by RT-PCR. The tissues used were endolymphatic sac, stria vascularis, organ of Corti, organ of Corti outer hair cells, cochlear nerve, Reissner's membrane, vestibular dark cells, and vestibular sensory cells. We show that multiple particulate (GC-A, GC-B, GC-D, GC-E, GC-F and GC-G) and several subunits of the heterodimeric cytosolic GCs (alpha1, alpha2, beta1 and beta2) are expressed, albeit at highly different levels. GC-C was not found. GC-A and the soluble subunits alpha1 and beta1 were transcribed ubiquitously. GC-B was present in all tissues except stria vascularis, which contained GC-A and traces of GC-E and GC-G. GC-B was by far the predominant membrane-bound isoform in the organ of Corti (86%), Reissner's membrane (75%) and the vestibulum (80%). Surprisingly, GC-E, a retinal isoform, was detected in significant amounts in the cochlear nerve (8%) and in the organ of Corti (4%). Although the cytosolic GC is a heterodimer composed of an alpha and a beta subunit, the mRNA transcription of these subunits was not stoichiometric. Particularly in the vestibulum, the transcription of the beta1 subunits was at least four-fold higher than of the alpha1 subunit. The data are compatible with earlier suggestions that membrane receptor GCs may be involved in the control of inner ear electrolyte and fluid composition whereas NO-stimulated GC isoforms mainly participate in the regulation of blood flow and supporting cell physiology.

The effect of anti-diuretic hormone on the endolymphatic sac of the inner ear

The anti-diuretic hormone vasopressin (AVP) regulates water excretion from the kidney by increasing the water permeability of the collecting duct. AVP binds to V2-receptors and induces the translocation of aquaporin-2 water channels (AQP-2) into the apical plasma membrane of principal cells. By this mechanism AVP controls water reabsorption in the kidney. The effects of AVP on the endolymphatic sac (ES) of the inner ear, which is thought to mediate reabsorption of endolymph, were investigated. Both the V2-receptor and the AQP-2 water channel were found to be expressed in the ES epithelium. In the ES AVP binds to receptors most probably of the V2-subtype. Application of AVP to organotypically cultured ES inhibits membrane turnover in ribosomal-rich cells of the ES epithelia, which is thought to mediate translocation of AQP-2 into the surface membrane. This suggests that AVP has contrasting effects in the inner ear and kidney, which may be physiologically useful for maintaining endolymphatic pressure during severe hypovolemia. Animal experiments show that AVP causes endolymphatic hydrops after systemic application to guinea-pigs, which suggests a causal role for the increased AVP levels found in humans suffering from Ménière's disease.

Detection of viral antigen in the endolymphatic sac

A study was devised to determine whether or not any immune defense mechanism is present when a virus invades the human endolymphatic sac (ES). The ES was removed from 14 fresh autopsy cases having no known pre-mortem diseases in the middle and inner ears. Specimens were then examined for viral antigens including herpes simplex (HSV) type 1 and 2, mumps and cytomegalovirus using immunohistochemical methods. DNA examination by in situ hybridization was also performed for HSV. HSV antigen and DNA were observed in 9 of the 14 cases studied. These findings suggest that the virus invades the ES but is impeded by an immune defense mechanism under normal conditions. Since disease may alter host defenses, further studies are warranted to study the relationship between HSV and patients with Meniere's disease.

Vascular permeability changes associated with experimentally induced facial nerve lesions in the rabbit

Changes in vascular permeability to sodium fluorescein following experimentally induced nerve lesions were examined in the rabbit facial nerve. Sodium fluorescein was injected intravenously as a permeability tracer and then localized by fluorescence microscopy. In control nerves, endoneurium showed only slight fluorescence while intense fluorescence was observed in the epineurium and perineurium. In nerves demonstrating edema and Wallerian degeneration, endoneurium was found to have an increased accumulation of tracer. This increased endoneurial vascular permeability in facial nerve lesions may explain nerve enhancement seen in gadolinium-enhanced magnetic resonance imaging in patients with facial nerve paralysis.

Interferon-induced sudden hearing loss

With the increasing long-term use of interferon (IFN), several new adverse effects have been recognized. Very little attention, however, has been paid to auditory acuity. We encountered 3 cases of sudden hearing loss associated with IFN. We then conducted a prospective study to assess the auditory function of 73 patients receiving IFN. Auditory disability (tinnitus and/or hearing loss) occurred in 32 patients (43.8%) during IFN therapy, among which audiometry documented sensorineural hearing loss in 27 cases (36.9%); 17 (48.6%) of the 35 patients receiving IFN-beta had auditory disability, including hearing loss in 13 cases (37.1%), and 15 (39.5%) of 38 patients receiving IFN-alpha suffered from auditory disability. There was not much difference between the influences of IFN-alpha and -beta. Auditory disability frequently developed in the later stages of treatment, and most patients recovered 7-14 days after the discontinuation of IFN. The results demonstrate that sudden hearing loss can occur as a side effect of treatment with IFN. This may reveal the association between autoimmunity and sudden hearing loss.

Vascular permeability to sodium fluorescein in the rabbit cranial nerve root: possible correlation with normal cranial nerve enhancement on gadolinium-enhanced magnetic resonance imaging

Vascular permeability in cranial nerve roots was examined after intravenous injection of sodium fluorescein in the adult rabbit. Fluorescence was observed in the distal nerves through the following portions: intracavernous portion of the oculomotor nerve, distal internal auditory canal segment of the facial nerve, and ganglionic portions of the trigeminal, glossopharyngeal and vagus nerves. In the acoustic nerve, the vestibular ganglion showed fluorescence. No fluorescence was observed in the olfactory or optic nerves. During in vivo gadolinium-enhanced magnetic resonance imaging (Gd-MRI) of two separate animals, trigeminal nerve enhancement was observed in the region showing fluorescence. Histologically, intense fluorescence was observed in ganglia and external nerve sheaths of the cranial nerves showing macroscopic fluorescence. A slight fluorescence was also seen in endoneurial connective tissue but not observed within the nerve fibers. The results of this study suggest that the physiological enhancement of human cranial nerves seen on Gd-MRI may correlate with vascular permeability.

[Sex hormones in fibrous dysplasia of the facial bone--an immunohistological study]

Fibrous dysplasia of the facial bones frequently occurs in the maxilla around the time of puberty and becomes inactive when skeletal growth is completed. A case of fibrous dysplasia of the maxilla and sphenoidal-temporal bone in a 19 year-old male was studied, in terms of the presence of estradiol, testosterone and dihydrotestosterone, using the peroxidase-antiperoxidase method. This case underwent partial surgical resection, for cosmetic deformity, of the maxillary tumor which, however, relapsed to preoperative size within three weeks. Estradiol and testosterone were strongly positive and dihydrotestosterone was slightly positive in the tumor cells. Sex hormones were apparently present in the tumor cells and exerted a strong influence on the growth of the fibrous dysplasia.

[Immunohistological study of the nasal mucosa in latent allergic patients]

We studied the distribution of T lymphocyte subpopulations and EG2 positive cells in the inferior turbinates of subjects with latent nasal allergy by use of an immunohistochemical procedure. Five patients who had a positive skin test for house dust and one who had a positive skin test for Japanese cedar were studied. The specimens were frozen at -70 degrees C and sliced at 4 microns with a cryostat. The peroxidaseantiperoxidase method with monoclonal antibodies (CD4, CD8, EG2) was used to detect T lymphocyte subpopulations and activated eosinophils. Finally, the specimens were counterstained with Mayer's Hematoxylin. CD4 positive cells and CD8 positive cells were found mainly in the superficial layer of the lamina propria. In every subject, the number of CD4 positive cells dominated that of CD8 positive cells in the lamina propria. The ratio of CD4 positive cells to CD8 positive cells was 1.93, on average. This ratio was lower than the ratio typical of nasal allergy, but higher than the ratio of non-allergic normal controls. Though the number of EG2 positive cells was lower than the number typical of nasal allergy, EG2 positive cells were observed in every case. We speculate that latent nasal allergic reactions may develop in the inferior turbinates.

Sex hormones in the kidney and endolymphatic sac. An immunohistological study

Autopsy specimens of kidney and endolymphatic sac were studied in terms of progesterone (P), estradiol (E), testosterone (T), dihydrotestosterone (DHT) and aldosterone (A) using the peroxidase-antiperoxidase method. The results obtained were as follows: The epithelial cells of the renal tubules were positive to P, E, T, DHT and A. The epithelial cells of the endolymphatic sac were also positive to these sex hormones though varying in stainability among cases. In view of the immunohistological findings of sex hormones and aldosterone, the resorptive and regulative function of the epithelium in the kidney and endolymphatic sac is discussed.

[Immunohistological study of eosinophilic infiltration of nasal polyps in aspirin-induced asthma]

It is well known that nasal polyps frequently develop in patients with aspirin-induced asthma, which is thought to be a non-atopic disease. We immunohistochemically examined the eosinophils infiltrating the nasal polyps in patients with aspirin-induced asthma. It has also been established that the monoclonal antibody EG1 reacts with both stored and secretion type ECP (eosinophil cationic protein), and that EG2 reacts only with the secretion type of ECP. EG2 positive cells may thus be considered to be activated eosinophils. Seven cases with nasal polyps associated with aspirin-induced asthma participated in our study. Blood eosinophilia was observed in all 7 cases, but 6 showed normal blood values IgE. Two reacted to house dust antigen, on skin tests and RAST. In the nasal polyps, many EG2 positive cells were observed. On serial sections, the number and distribution of EG1 and EG2 positive cells were almost equal. In the superficial lamina propria, extra-cellular release of ECP was noted. However, epithelial damage did not relate to the number of EG2 positive cells or the degree of extra-cellular EG2 release. In the deep lamina propria, slight extra-cellular ECP release was found. From these results, the eosinophils in nasal polyps accompanying aspirin-induced asthma were thought to be activated. Eosinophils seem to play an important role in the development of nasal polyps. However, tissue injury induced by eosinophils, was not be demonstrated in this study.

[Immunohistologic study of the nasal mucosa with reference to Langerhans cells]

The distribution of Langerhans cells in human oral mucosa, nasal mucosa and nasal polyps was studied by means of immunohistochemistry. Our study involved 35 participants. The specimens were frozen to -70 degrees C and sliced at 4 microns with a cryostat. Monoclonal antibodies CD1 (OKT6) and the peroxidase-antiperoxidase staining method were used to detect Langerhans cells. In the oral mucosa and the nasal vestibule lined with stratified squamous epithelium, CD1 positive cells were observed and these cells were dendric in form. The cells were found mainly from the intermediate layer to the deep layer of the epithelium. In the inferior turbinate lined with ciliated epithelium, we could not find any CD1 positive cells at all. The nasal polyps in some cases had a normal ciliated columnar epithelium while others had metaplastic stratified squamous epithelium. Both types of epithelium in the same polyp were noted on some occasions. In nasal polyps, CD1 positive cells which showed dendric form were found in the metaplastic squamous epithelium only, and could not be observed in the ciliated columnar epithelium at all. Based on the above results, the presence of Langerhans cells is confirmed not by the anatomical location but by the type of epithelium. Langerhans cells could be detected only in the squamous epithelium. Keratinocytes, which constitute the squamous epithelium, are known to release cytokines. IL-1 (interleukin-1) and GM-CSF (granulocyte-macrophage colony stimulating factor) released from keratinocytes are thought to influence the viability and function of Langerhans cells. The migration of Langerhans cells into squamous epithelium may be regulated by cytokines released from keratinocytes.

Sex hormones in juvenile nasopharyngeal angiofibroma tissue

Five cases of juvenile nasopharyngeal angiofibroma were studied in terms of the presence of progesterone, estradiol, testosterone, and dihydrotestosterone in the juvenile nasopharyngeal angiofibroma tissue using the peroxidase-antiperoxidase method. Progesterone and estradiol were positive in all cases. Testosterone was positive in 2 of the 5 patients. Dihydrotestosterone was positive in 3 of the 5 patients. Hormone in the juvenile nasopharyngeal angiofibroma tissue seems to change by the activity of nasopharyngeal angiofibroma.

Estradiol and testosterone in minor salivary glands of Sjögren's syndrome

Nine patients with Sjögren's syndrome were studied in terms of estradiol, testosterone, and dihydrotestosterone in the labial minor salivary glands using the peroxidase-antiperoxidase method. In normal controls in women, estradiol was positive in the epithelial cells of duct, but testosterone and dihydrotestosterone were negative or doubtfully positive by case. Thus, it seems that there is a sex difference of receptors in the ductal epithelia. In the labial minor salivary glands of the patients, all estradiol, testosterone, and dihydrotestosterone were positive. As the background of Sjögren's syndrome, it seems that there is an influence of sex hormones.

Altered distribution of motor neurons in experimental facial nerve paralysis

The alteration of motor neurons in the brainstem after recovery from experimental facial nerve paralysis was examined by the retrograde horseradish peroxidase (HRP) technique in the rabbit. Six months after nerve crush injury at the center of the vertical portion, HRP was injected into the zygomatic muscle on the recovered side. The distribution of labelled neurons in the brainstem was compared with that in the normal rabbit. In control animals, motor neurons in the facial nucleus were somatotopically organized, and there were no labelled neurons in other nuclei in the brainstem. In recovered animals, on the contrary, the somatotopic organization of the facial nucleus was obscure and multipolar neurons of varying size were labelled bilaterally in the reticular formation from the pons to the medulla.

A case of delayed endolymphatic hydrops

A 30-year-old male with delayed endolymphatic hydrops was given a sac operation. An intradural portion of the endolymphatic sac was resected and the epithelial surface was examined under a scanning electron microscope. The epithelium showed fibrous degeneration and disappearance of the epithelial cells. Pathogenesis of degeneration of the endolymphatic sac is discussed.

Endolymphatic hydrops induced by noise exposure

In animal with cochlear deafness induced by firecracker explosion, fibrous degeneration of the endolymphatic sac was observed 4 months after the disappearance of Preyer's reflex. Endolymphatic hydrops induced by noise exposure may develop as the results of degeneration of the endolymphatic sac due to cochlear deafness by acoustic trauma after the lapse of a long period of time.

[Clinical and immunohistological findings of juvenile nasopharyngeal angiofibroma experienced in the last six years]

Five patients with juvenile nasopharyngeal angiofibroma were found between 1984 and 1990 in our department. Clinical findings, treatment, and postoperative follow-up were reported. Two patients belonged to stage III and remnant 3 patients belonged to stage I. In cases of stage I, a surgical approach through the suprahyoid pharyngotomy was a worthy procedure to try, because angiofibroma was observed under direct vision and hemostasis was easy. In therapeutic planning, the authors emphasized the need of a preoperative staging classification based on CT scanning and selective angiography. In immunohistochemical studies, Langerhans cells with S-100 protein positive were found. Fibroblasts revealed estradiol positive but testosterone showed negative in all cases. Thus, juvenile nasopharyngeal angiofibroma was considered to be neoplasm related estradiol.

Testosterone and estradiol in juvenile nasopharyngeal angiofibroma tissue

Five cases of juvenile nasopharyngeal angiofibroma (JNA) were studied in terms of the presence of testosterone and estradiol in the JNA tissues using the peroxidase-antiperoxidase method. Testosterone was found to be negative and estradiol positive in all cases. JNA is considered to be a tumor associated with estradiol.

Positional nystagmus due to alteration of the specific gravity in the labyrinth

Horizontal positional nystagmus having characteristics similar to ice water caloric nystagmus was induced by injecting heavy water into the rabbit middle ear cavity or facial nerve through the stylomastoid foramen. Furthermore, with general administration of glycerol to normal subjects, horizontal positional nystagmus as with general administration of heavy water to experimental animals was observed. It is possible that alteration of the specific gravity arising from infiltration of heavy water or glycerol into the labyrinth accounts for the manifestation of positional nystagmus. These studies on positional nystagmus may be one of the means to elucidate the mechanism of caloric nystagmus and to examine the function of the human blood-labyrinth-barrier.

Scanning electron microscopy and immunoglobulins of the endolymphatic sac in Menière's disease

SEM and immunoglobulin staining of the intradural portion of the endolymphatic sac (ES) were investigated. All 15 normal subjects, from fetuses to an 80-year-old adult, showed well arranged epithelial cells. In Menière's disease (all 15 patients) the ES showed various types degeneration of the epithelial cells. Inner ear deafness experimentally produced by kanamycin injection showed a similar degeneration of the ES. IgG of the ES in Menière's disease showed moderately evident deposits compared with normal subjects. However, these findings were also found to the same degree as IgG deposits in animal deafness produced by KM injection. From the above results it can reasonably be concluded that the degenerated findings of the ES and deposits of the IgG in Menière's disease may possibly be the result of cochlear deafness.

[Detection of immunoglobulin in the inner ear tissue by PAP method]

The distribution of immunoglobulins IgG, IgA and IgM in the inner ear tissue from a patient who died of lung bleeding followed after sepsis was studied, and also the normal guinea pig inner ears and the inner ear disorders induced by Kanamycin injection were studied for the distribution of IgG. The temporal bones were fixed in formaldehyde, decalcified in EDTA and embedded in paraffin. The PAP method was used for the demonstration of the immunoglobulins. In both the human inner ear tissue and the normal control inner ear tissue of the guinea pigs deposits of IgG were found in the sensory organs and the endolymphatic sac, however, in the stria vascularis was slight. The severe damaged inner ears induced by Kanamycin the remarkable decreased deposits of IgG were found in the cochlea, but in the endolymphatic sac the remarkable increased deposits of IgG were found. No IgA and IgM were found in the human inner ear tissue.

[Experimental positional nystagmus induced by argon laser irradiation to the oval window]

Experimental positional nystagmus (EPN) similar to benign paroxysmal positional nystagmus (BPPN) was induced in 8 of 20 rabbits by argon laser irradiation to the footplate. The power of the argon beam used was 2.0 watts and irradiation time was 1 or 2 sec. EPN and BPPN showed the following similarities maintained (1) When the head was maintained in the affected ear down position and the head positioned from the sitting to the supine position nystagmus directed to the affected ear or vertical nystagmus corresponding to rotatory nystagmus in man were provoked. (2) Delayed onset for provocation of nystagmus. (3) Limited duration. (4) Fatigability. (5) The direction of nystagmus was reversed when the head returned to the initial position (in two rabbits). Histological examination of the temporal bones showed separation of otoconia from the otolithic membrane of the saccule and bleeding in the saccule in both conditions. No lesions in the utricle and semicircular canals were evident. It was assumed that ablation of otoconia of the saccule causes this experimental positional nystagmus.

Scanning electron microscopy and immunoglobulins of the endolymphatic sac in normal human subjects and sensorineural deafness. With special reference to Menière's disease

The pathophysiology of the endolymphatic sac (ES) in Meniere's disease was studied by scanning electron microscopy and staining of immunoglobulins in the intradural portion of the ES. The peroxidase-antiperoxidase method by means of paraffin sections was used for staining of immunoglobulins. First, subjects without hearing impairment and malformation of the temporal bone, ranging from a 7-month-old fetus to an 80-year-old adult, were investigated. All subjects, including fetuses, showed well-arranged epithelial cells by scanning electron microscopy. The epithelial cells in the proximal portion of the intradural ES were oval, showing a tendency of transitional change to be flat as they drew near the distal portion of the ES. The epithelial cells consisted mostly of light cells, but sporadic dark cells were seen. Regarding the immunoglobulins. IgG was slightly positive in the epithelial and subepithelial layers. All 15 patients with Meniere's disease showed various types of degeneration of the epithelial cells though to varying degrees. However, these findings were also seen in cases of cochlear deafness. On the other hand, the ES of acoustic tumors, with retrocochlear or neural deafness revealed a normal finding, as found in healthy subjects. Inner ear deafness experimentally produced in animals by Kanamycin sulfate (KM) injection showed degeneration of the epithelial cells of the ES similar to that found in human cochlear deafness. IgG of the ES in Meniere's disease showed moderately evident deposits compared to normal subjects. However, this was also found not only in inner ear deafness other than Meniere's disease, but also in animal deafness experimentally produced by KM injection. It is very interesting to note that moderate endolymphatic hydrops was found in animals one year after Preyer's reflex had disappeared. It is postulated that endolymphatic hydrops develop because of impairment of endolymphatic fluid resorption at the rugose portion and stenosis of the lumen in the same portion, due to degeneration of the epithelial cells. From the above results, it is argued that degenerated epithelial cells and immunoglobulins of the ES in Meniere's disease may arise from the sequelae of cochlear deafness. It is also hypothesized that endolymphatic hydrops--at least in the terminal stage of Meniere's disease--may be consistent with the same pathophysiological conditions as in animal experiments.

[A case of nasopharyngeal amyloidosis]

A case of amyloidosis localized in the nasopharynx was reported. The patient was a 62-year-old female who complained of persistent nasal obstruction. The gross appearance of this tumor showed a thumb-sized red-yellowish mass, in part covered with white coating. The systemic amyloidosis was excluded by several clinical examinations including rectal biopsy. Histopathological examination revealed diffuse deposits of homogeneous eosinophilic substances. A polarized microscopic examination by congo-red stain showed that deposit's substances were amyloid. A typical amyloid fibril was observed under electron microscope. The mass was removed with Beckmann adenotome. Bleeding was minimal.

Prognostic estimation of sudden deafness by cochlear microphonics of electrocochleography

Estimation of the prognosis of sudden sensorineural deafness is available by reviewing CM responses in electrocochleography (ECochG) even at an early stage of disease after the onset. The detection threshold of CM irrespective of the period of ECochG seems to be the most reliable tool to estimate the final hearing level in pure tone audiogram.

[A case of facial nerve schwannoma extending into the middle cranial fossa with characteristic CT findings]

Facial nerve schwannoma is rare. Since the first description by Schmid, about 150 cases have been reported mainly in the otological field. The authors recently had a case of facial nerve schwannoma with a marked capsular calcification, extending into the middle cranial fossa. A 63-year-old man was admitted to our hospital on June 20, 1986. About 44 years prior to the admission, he noted facial weakness of the right side which gradually progressed. Neurological examination on admission revealed complete right facial paralysis of the peripheral type with loss of taste, right hearing loss, diminution of lacrimal secretion and no reaction to caloric stimulation. Stenvers' view and tomogram of the right temporal bone showed destruction of petrous ridge. CT scan demonstrated bony destruction of the right petrous pyramid and high dense mass lesion, extending into the middle cranial fossa. Peritumoral and intratumoral calcifications, characteristics of facial nerve schwannoma were also noted. Right external carotid angiography demonstrated the tumor was fed by petrous branch of the right middle meningeal artery. On July 11, 1986 right temporal craniotomy and extradural approach to the floor of the petrous portion of the middle cranial fossa were performed. There was an extradural mass which extended to the middle cranial fossa through the destroyed pyramis. The tumor appeared to originate from the geniculate ganglion of the facial nerve and invaded the inner and middle ear which were almost completely removed. Operative specimen demonstrated that the tumor was a schwannoma. Postoperative hearing test and facial nerve function showed no changes as compared with preoperative findings. Similar case reports with CT findings were reviewed.

Reliability of cochlear microphonics in clinical electrocochleography

A study was made on the reliability of cochlear microphonics (CM) recorded in clinical electrocochleography (ECochG) by the transtympanic electrode technique. In normal-hearing subjects, the CM shift increased as the frequency was lowered at the same sound pressure, and as the sound pressure was lowered at the same frequency. The CM shift for the frequencies from 8 to 0.5 kHz was greater as the sound pressure was lowered. The above results suggest that clinical ECochG CM responses may well reflect the potential of the cochlea.

Fluorescence findings of the facial nerve at decompression operation

Decompression operation was performed on patients with Bell's palsy and facial nerve palsy due to temporal bone fracture or otitis media, and a study was made on the relation between the fluorescence findings of the nerve and prognosis. The fluorescence of nerve was visible in 4 cases of Bell's palsy but none of the patients was completely cured, though the degree of cure tended to be proportional to the intensity of fluorescence. On the other hand, cure was seen even in cases of facial nerve palsy due to temporal bone fracture or otitis media that showed no fluorescence or any response in the maximal stimulation test (MST). It is suggested that Bell's palsy and facial nerve palsy due to trauma or otitis media do not share the same pathophysiology.

Electrocochleographic study of low-tone hearing loss without vertigo

Auditory nerve action potential (AP), cochlear microphonics (CM) and summating potential (SP) were recorded from 6 patients with low-tone hearing loss without vertigo. All these cases showed high AP and -SP amplitude and satisfactory CM response. These findings resembled the electrocochleographic findings of type 1, which is an early stage of Ménière's disease. Hearing returned to normal range in half of the cases but remained hardly changed in the other half. The difference between these two groups could not be clarified electrocochleographically. On the other hand, low-tone hearing loss due to retrolabyrinthine lesion and due to familial sensorineural deafness was shown to have a low AP amplitude.

Chronological changes of electrocochleogram in experimental endolymphatic hydrops. Special reference with AP output potential and hair cell cilia

Chronological changes of the whole nerve action potential (AP), cochlear microphonics (CM) and summating potential (SP) in experimental endolymphatic hydrops in guinea pigs were studied during a period from 1 week to 13 months after the endolymphatic sac obliteration. Endolymphatic hydrops became extensive in month 3 and persisted thereafter. The threshold of AP increased with the lapse of time but good AP output potential was obtained, being maximum in month 3. The threshold of CM increased with the lapse of time. The CM output potential was the highest around week 3 when endolymphatic hydrops was slightly formed, and it decreased thereafter. SP responses at the frequencies of 8, 4, 1 and 0.5 kHz showed the reversed polarity of -SP in month 3 and changed towards potential 0 thereafter. In animals showing super-normal AP output potential, the cilia in the third row of outer hair cells were disarranged. This seems to be involved in recruitment.

Electrocochleographic study of Ménière's disease

Auditory nerve action potential (AP), cochlear microphonics (CM), and summating potential (SP) were recorded from 32 patients with Ménière's disease. Patients were classified into three groups according to the degree of their hearing impairment. The group of patients that had a mild to moderate hearing loss and whose hearing was reversible showed notably satisfactory responses for AP, CM, and negative SP (-SP), and also showed a high incidence of positive SP (+SP). Low responses for AP and CM with an increase of detection thresholds and a high -SP/AP ratio were obtained from patients with moderate hearing impairment, whose hearing fluctuated slightly. These electrocochleographic findings were suggestive of the pathophysiologic differences at the various stages of Ménière's disease.

Cancer of the head and neck in atomic bomb survivors: Hiroshima and Nagasaki, 1957-1976

A search was conducted in Hiroshima and Nagasaki for all cases of cancer of the lip, nose and nasal cavity, accessory sinuses, larynx, and the oral cavity and pharynx with their subdivisions occurring during the period 1957-1976 among a large, fixed cohort of atomic bomb survivors. A total of 232 cases were identified, of which 154 (66.4%) were histologically confirmed (definite cases). Among definite cases, cancer of the epiglottis and larynx predominated (31.2%), followed by accessory sinus (24.7%) and tongue (18.8%). Of the 154 definite cases, 141 (91.6%) were squamous-cell carcinomas. Only two sarcomas were identified, neither of which was attributable to radiation exposure. Analysis of both total and definite cases, by both total group and major anatomic site, failed to reveal definite evidence of a radiation relationship. Although a suggestive relationship to radiation dose was found for accessory sinus cancers (P = 0.06) among the definite cases, inconsistencies in the data do not permit the conclusion that the incidence of tumors in this group increased as a result of atomic bomb radiation exposure. The medical literature concerning post-irradiation head and neck tumors is briefly reviewed.

Electrocochleographic study of patients with cerebral vascular lesions

Electrocochleographies were performed on three patients with deafness resulting from cerebral vascular lesions. Recording was made by the transtympanic needle electrode technique. In a patient who had anterior-inferior cerebellar artery aneurysm that showed fluctuating hearing loss, auditory nerve action potential (AP), cochlear microphonics (CM), and summating potential fluctuate in amplitude in concert with episodes of ischemic hearing loss. This indicates the pathophysiology of reversible impairment of the cochlear nerve and of sensory epithelium of the inner ear caused by disturbance of blood flow into the inner ear. It was also conjectured that the cochlea is hardly impaired in the case with normal AP and CM responses despite the increased threshold in pure-tone audiometry and that the cochlea undergoes irreversible organic changes in the patient who has no AP or CM response in tests after a long period.

Changes of the action potential, the summating potential and cochlear microphonics in experimental endolymphatic hydrops

The changes of the action potential (AP), the summating potential (SP) and cochlear microphonics (CM) were investigated in reference to the grade of endolymphatic hydrops produced by endolymphatic sac obliteration in guinea pigs. In a few cases with minimum endolymphatic hydrops, super-normal AP was obtained. With an increase of endolymphatic hydrops, CM responses were reduced although AP responses at intensive stimulation were maintained relatively well. It is thought that the polarity of positive SP, as observed in control, was influenced to deflect towards negative SP by an interaction between the increased degree of endolymphatic hydrops and the changes of the biochemical components of the inner ear fluids.

Conditions of clinical recovery from partial facial palsy caused by injury to a branch of the facial nerve

This study was conducted to elucidate the pattern of clinical recovery from partial facial palsy caused by injury to a branch of the facial nerve in rabbits. In the experiment, the state of recovery from palsy was investigated by observing the movement of the m. orbicularis oris of the rabbit at the time of food intake, as well as by observing the evoked wave and muscle contraction caused by nerve stimulation, and the muscle contraction caused by muscle stimulation. Recovery from peripheral facial nerve palsy is complete within 1 month after nerve impairment if over half of the nerve fibers of the impaired nerve are maintained intact without degeneration.

Experimental labyrinthine disorders and direction of nystagmus

The purpose of this paper is to demonstrate the variation of the direction of nystagmus which is elicited from the peripheral labyrinth. The direction of nystagmus depends, among other things, on the nature of the stimulus. Depending on the degree of pathophysiological conditions in the labyrinth, atypical nystagmus which does not comply with the rule is occasionally elicited even though the same stimulus is given. Hyperfunctional stimulation to the labyrinth, such as allergy, causes nystagmus which beats to the affected side and also shows hyperactivity of the whole nerve action potential and cochlear microphonics.

Anisocoria in inner ear lesions

In experiments using rabbits, the pupil on the side of irritative inner ear lesion showed dilatation, and that on the side of paretic lesion showed constriction. In the clinical observation of patients with unilateral inner ear diseases (134 cases), anisocoria was recognized in 54.5%. In 68.5% of these, anisocoria was induced after applying a drop of neosynephrine. The size of the pupil on the healthy side was smaller in 65.8% than the pupil on the healthy side. Anisocoria in inner ear lesions is believed to be due to vestibulo-sympathetic imbalance through the superior cervical sympathetic ganglion.