Reliability of the promontory stimulation test for the preoperative evaluation of cochlear implants: a comparison with the round window stimulation test

The electrical stimulatory threshold of the preoperative promontory stimulation test (PST) was compared with the postoperative threshold of the electrode following cochlear implantation. Postoperative results from warble-tone audiometry, the vowel recognition test, the consonant recognition test, and the speech tracking test, which employed a speech processor, were similarly evaluated. In certain patients who responded insufficiently to the PST, an exploratory tympanotomy under local anesthesia was performed prior to cochlear implantation, and stimulatory threshold was measured with an electrode placed directly on the round window [round window stimulation test (RWST)]. No correlation was found between the PST results and the postoperative performance of the cochlear implant. The RWST was determined to be better than the PST in the evaluation of cochlear implant performance.

Cochlear implantation: preoperative counselling and postoperative problems

Some patients cannot understand the reasons for a cochlear implant, nor the implications of such a device, and thus a clear explanation is required during patient counselling. Approximately one tenth of the patients with hearing loss examined in our hospital have received cochlear implants. Adequate preoperative examinations can make the surgery less difficult. Following cochlear implantation, speech comprehension of the patients with prelingual hearing loss is poor, and even patients with good speech comprehension have complaints about the clarity of the voice by the cochlear implant.

[Recent advances in clinical application of event-related potentials]

Auditory and somatosensory ERPs were studied in patients with dementia of the Alzheimer type (DAT), those with vascular dementia and demented patients with idiopathic Parkinson disease. In both auditory and somatosensory modalities, the P3 latency in the demented patient group was significantly prolonged compared with the control data. However, comparisons of the P3 latency among the patients with DAT, vascular dementia and demented Parkinson did not reveal any significant differences. Patients with vascular dementia had significantly prolonged N140 and P200 latencies in somatosensory ERPs, whereas N1 and P2 latencies in auditory ERPs did not show any significant differences. Patients with acute onset hippocampal amnesia showed normal auditory P3 and somatosensory P3, whereas patients with diencephalic amnesia had prolonged auditory P3 and somatosensory P3 in addition to the abnormal short latency somatosensory evoked potentials. Analysis of passively evoked P3 component and comparison between target P3 and passively evoked P3 may be useful for evaluation of demented patients with a variety of etiologies. Single-trial analysis showed a greater variance of P3 latency in demented patients than in control subjects. A greater variance of P3 resulted in 'absent P3' in conventional averaging in some of the demented patients. As vigilance levels changed from trial to trial, evaluation of P3 latency variance has been proven to be useful.

Hirschsprung disease, unusual face, mental retardation, epilepsy, and congenital heart disease: Goldberg-Shprintzen syndrome

A 5-year-old girl with Hirschsprung disease, unusual facial appearance, psychomotor retardation, epilepsy, and congenital heart disease is reported. Patients with similar clinical features have been reported and they appear to exhibit the recently identified Goldberg-Shprintzen syndrome. It is believed that this girl also exhibits this new syndrome. Cranial computed tomography demonstrated abnormal findings that may suggest defective neuronal migration and/or dysgenesis of the brain. These findings were considered to cause psychomotor retardation and epilepsy in this patient.

Positron emission tomography of auditory sensation in deaf patients and patients with cochlear implants

The present study investigated the function of the auditory cortices in severely hearing-impaired or deaf patients and cochlear implant patients before and after auditory stimulation. Positron emission computed tomography (PET), which can detect brain activity by providing quantitative measurements of the metabolic rates of oxygen and glucose, was used. In patients with residual hearing, the activity of the auditory cortex measured by PET was almost normal. Among the totally deaf patients, the longer the duration of deafness, the lower the brain activity in the auditory cortex measured by PET. Patients who had been deaf for a long period showed remarkably reduced metabolic rates in the auditory cortices. However, following implantation of the cochlear device, the metabolic activity returned to near-normal levels. These findings suggest that activation of the speech comprehension mechanism of the higher brain system can be initiated by sound signals from the implant devices.

Efferent vestibular fibers to otolith organs in guinea pigs

The origins of efferent vestibular fibers to the otolith organs in guinea pigs, examined with the use of retrograde transport of HRP were: i) the bilateral lateral portions of the facial genu and ii) the ipsilateral reticular nucleus at the level of the facial nucleus. These origins are almost the same as those of the efferent fibers to the three semicircular canals which we have previously identified in cats; however, they differ in certain respects.

Mechanisms of alpha-Sialosyl cholesterol action to suppress both cyclic AMP production and DNA synthesis of rat glial cells

alpha-Sialosyl cholesterol (alpha-SC) that elicited morphological differentiation of rat astrocytes not only lowered intracellular cyclic AMP (cAMP) levels but also inhibited cAMP production induced by either alpha-isoproterenol, cholera toxin, or forskolin. The targets of alpha-SC in the cAMP production system of rat astrocytes were investigated to understand the mechanism of the alpha-SC action on cAMP production. cAMP production evoked by alpha-isoproterenol (1 microM) was entirely canceled by beta blockers such as propranolol and timolol (1 microM), but not by alpha-SC. Concentrations of alpha-SC greater than 15 microM were required for 50% inhibition of the activation by a beta agonist. Although alpha-SC inhibited in a dose-dependent manner the activities of membrane-associated adenylate cyclase that had been stimulated by either GTP gamma S of forskolin, alpha-SC inhibited neither GTP-binding activities nor GTPase activities of the membrane-associated G proteins. These findings suggest that alpha-SC suppresses adenylate cyclase directly, but not beta receptors or G proteins, and that it promotes the morphological differentiation of rat astrocytes through a mechanism regulating directly the cytoskeletal organization, regardless of intracellular cAMP level. alpha-SC (30 microM) suppressed 40% of DNA synthesis in the cell-free system, which contained the cytosolic extracts and the nucleus fraction prepared from rat astrocytoma C6 cells. Approximately 25% of alpha-SC incorporated in the astrocyte cytoplasm was transferred to the nuclei by 10 min after the addition.(ABSTRACT TRUNCATED AT 250 WORDS)

[Multichannel cochlear implantation in a deaf child]

A multichannel cochlear implantation was performed in an 8-year-old child and the following results were obtained. The surgical procedures were not particularly difficult as compared to cochlear implantation for adults. Postoperative rehabilitation requires a longer time than in adult patients. Cochlear implants are useful not only for the recognition of environmental sound but also for the recognition of speech. Cooperation with the medical facility, as well teachers and family members, is essential.

[A case of spontaneous spinal epidural hematoma]

A 14-month-old girl with spontaneous spinal epidural hematoma and complete postoperative recovery was described. MRI proved to be a sensitive tool in identifying the nature and extent of this lesion. A review of literature was made with particular emphasis on the pediatric age group.

Considerations of cochlear implant surgery

Although cochlear implants have been reported to be easy to perform, some difficulties have been experienced in 4 of 21 operations. In order to make this surgery easier, the following points should be considered. Pre-operative CT and MRI must be performed in order to determine the condition of the cochlea. To determine the condition of the round window, exploratory tympanotomy is recommended in some cases. After insertion of the electrode in the cochlea, a radiograph should be taken during the operation to confirm that the electrode is correctly positioned.

[MRI findings of olivopontocerebellar atrophy and Machado-Joseph disease--diagnostic value of transverse pontine fibers]

Olivopontocerebellar atrophy (OPCA) and Machado-Hoseph disease (MJD) occasionally show similar clinical signs and symptoms, which makes differential diagnosis of OPCA and MJD difficult. In 1990, Savoiardo et al. reported that the transverse pontine fibers of OPCA patients had high signal intensity on T2 weighted MR images. To determine if the high signal intensity of the transverse pontine fibers is useful for the differential diagnosis of OPCA and MJD, we examined this abnormal intensity in patients diagnosed as OPCA or MJD. We observed the high intensity of transverse pontine fibers in all of the 18 OPCA patients. This finding, however, was not observed in any of the patients with the MJD. The high signal intensity of the transverse pontine fibers in T2 weighted images is characteristic of OPCA patients. Furthermore the atrophy of pontine tegmentum is characteristic of patients with MJD. These findings correlate well with pathological findings of OPCA and MJD, indicating the usefulness of these MRI findings for the differential diagnosis of OPCA and MJD.

Effect of somatostatin and its analogue on proliferation of human epidermoid carcinoma cells in vitro

Somatostatin (SS) and its analogue inhibit the growth of some human tumors in vivo. Surprisingly, we found that SS-14 and its analogue (SMS 201-995) exhibited unexpected proliferative effects on two lines of cells, A431 and KB human epidermoid carcinoma cells, in vitro. The level of intracellular cyclic AMP, an important second messenger that controls the growth of A431 cells, was unaffected in A431 cells by either SS-14 or SMS 201-995. In contrast, SS-14 (20 nM) and SMS 201-995 (10 nM) reduced the level of intracellular inositol 1,4,5-trisphosphate rapidly but transiently.

Effect of ascorbic acid on pituitary prolactin secretion in the non-ascorbate synthesizing Osteogenic Disorder Shionogi (ODS) rat

We examined the secretion of prolactin (PRL) in the hereditary scurvy-prone Osteogenic Disorder Shionogi (ODS) rat to investigate the role of ascorbic acid (AsA) in pituitary lactotroph and hypothalamic function. Plasma PRL concentrations of conscious AsA-deficient or control ODS rats were measured before and after the administration of metoclopramide (MCP), 5-hydroxy-L-tryptophan (5-HTP) or saline. The basal plasma PRL levels did not differ between the two groups. However, the AsA-deficient rats exhibited significantly larger changes in plasma prolactin concentration in response to MCP or 5-HTP than the control ODS rats. Thus, AsA deficiency enhanced the stimulated, but not the basal, secretion of PRL in ODS rats. Our findings suggest that AsA may have an inhibitory effect on PRL secretion.

CT of the pacchionian body

The CT appearances of the pacchionian body, confirmed at autopsy, are reported. The pacchionian body appears as a low density mass in the dural venous sinus, of almost the same density as the subarachnoid space.

Excretion of urinary epidermal growth factor in non-insulin dependent diabetes mellitus

Morning urine samples were assayed for human EGF (hEGF) in 137 non-insulin dependent diabetic patients with normal serum creatinine and beta 2-microglobulin levels. Serving as controls, 80 age- and sex-matched healthy subjects were also examined. A significant positive correlation between hEGF excretion and the level of hemoglobin A1C (HbA1c) was present in those patients with a HbA1c value exceeding 8% (r = 0.37; p = 0.003) but not in the overall patients. The urinary hEGF level did not correlate with the concentration of glucose in urine or plasma. The mean urinary hEGF level of diabetic patients was significantly lower than that of healthy subjects. The mean urinary hEGF level was significantly lower in the patients with a diabetic history that exceeded five years as compared with those with a history below five years. The mean urinary hEGF level was significantly lower in the patients with retinopathy vs. those without retinopathy. In the patients with HbA1c value below 8%, the mean urinary hEGF level was lower in the patients whose urinary albumin level exceeded 1.7 mg/mmol.creatinine as compared with those whose urinary albumin excretion was below 1.7 mg/mmol.creatinine. These findings suggest that urinary hEGF excretion may decrease with the progression of diabetic complications in the patients with well-controlled glycemia, and that inadequate glycemic control may lead to an increased excretion of urinary hEGF in the early disease stage.

Autonomic innervations in the middle ear and pharynx

Autonomic innervations of the mucosa in the middle ear and pharynx were investigated by retrograde labelling of the autonomic ganglia with horseradish peroxidase (HRP). Of the sympathetic ganglia, the superior cervical ganglion (SCG), middle cervical ganglion (MCG) and stellate ganglion (StG) were examined, and of the parasympathetic ganglia, the pterygopalatine ganglion (PpG) and the otic ganglion (OtG) were examined. Sympathetic innervation of the middle ear mucosa was accomplished by fibers originating in the ipsilateral SCG, but not by those originating in the MSG or StG. Parasympathetic innervation was by fibers originating in the ipsilateral PpG, but not by those originating in the OtG. The epipharynx received sympathetic innervation from the ipsilateral SCG, but not from the MCG or StG. Its parasympathetic innervation was from the PpG bilaterally, but not from the OtG. Sympathetic innervation of the mesopharynx was supplied by the SCG, MCG and StG, but no parasympathetic supply came from the PpG or the OtG. Sympathetic innervation was bilateral, but predominantly from the ipsilateral side. The hypopharynx resembled the mesopharynx, but had more innervation from the MCG and StG.

Auditory event-related potentials in patients with systemic lupus erythematosus

We studied auditory event-related potentials (ERPs) in 17 patients with systemic lupus erythematosus (SLE). Latencies of N100 and P200 components were normal in all patients, whereas the latencies of target P300 and nontarget P300 components were significantly prolonged in SLE patients with and without cognitive dysfunction. The P300 component of ERPs can be applied to evaluate the cognitive aspects of central nervous system manifestations in SLE patients.

T-cell receptors and collagen induced arthritis in H-2r mice

Mouse strains B10, B10.RIII, RIIIS/J and the F1 and backcross progeny arising from them were tested for susceptibility to porcine type II collagen-induced arthritis (PII-CIA). The clinically severe arthritis of rapid onset that is characteristic of PII-immunized B10.RIII mice developed predominantly in hybrid offspring that had inherited at least one copy of wild type T cell receptor (TCR) genes (V beta b genotype) from the B10 or B10.RIII parent. The results indicate that, in the development of PII-CIA, mice expressing the H-2r/r haplotype preferentially utilize TCR V beta genes that are normally encoded within the TCR V beta genomic deletion region of RIIIS mice (V beta c). After aggressive immunization with PII, the use of alternative TCR V beta genes, encoded outside of the RIIIS deletion region, produced a high IgG antibody response that was cross-reactive with mouse type II collagen (MII) and equivalent to that of B10.RIII mice, but only a very mild, late onset arthritis of 56% (27/48) incidence in RIIIS male mice and 28% (10/35) incidence in RIIIS female mice. In comparison, B10.RIII mice routinely developed early onset of PII-CIA of significantly higher incidence (100%; p < 0.005) and four-fold greater severity, even after milder immunization protocols. The data are compatible with the proposal that the clinically weak CIA response of RIIIs mice may be primarily antibody driven while the severe CIA of B10.RIII mice reflects the added inflammatory effects of collagen-reactive effector-T cells in the joint.(ABSTRACT TRUNCATED AT 250 WORDS)

Increased content of epidermal growth factor in platelet lysates in non-insulin-dependent diabetes mellitus

We evaluated the content of EGF in platelet lysates obtained from 49 patients with non-insulin-dependent diabetes mellitus (NIDDM)(18 males, 31 females, age 58 +/- 13 years) and from 23 clinically healthy control subjects (11 males, 12 females, age 53 +/- 18 years). Platelets were collected from platelet-rich plasma and lysed. EGF was determined by radioimmunoassay. The immunoreactive EGF content in the platelet lysates in diabetic patients significantly exceeded that of control subjects (44.9 +/- 18.5 pg/mm3platelet vs. 34.2 +/- 7.8 pg/mm3platelet, mean +/- SD p < 0.008). In performing multiple regression analysis with ten clinical parameters, urinary albumin excretion (F = 16.1, r = 0.551, p < 0.001), duration of diabetes (F = 13.0, r = 0.511, p < 0.001) and the presence of diabetic proliferative retinopathy (F = 8.8, p < 0.01) were significantly associated with irEGF content in platelet lysates. These observations suggest that the amount of EGF in platelets may increase with the progression of diabetic complications. The mechanism for the increase of EGF in platelets remains to be clarified.

Primary non-Hodgkin malignant lymphoma of the breast. An immunohistochemical study of seven patients and literature review of 152 patients with breast lymphoma in Japan

BACKGROUND

The breast is rarely a primary site for extranodal malignant lymphoma. Most reported primary non-Hodgkin malignant lymphomas of the breast (PBL) are of B-cell phenotype.

METHODS

Histologic and immunohistochemical analyses of seven patients with PBL and a statistical analysis of 152 patients with PBL reported in the Japanese literature were performed.

RESULTS

Malignant lymphoma could not be predicted preoperatively with clinical and radiologic findings; breast carcinoma, fibroadenoma, and phyllodes tumor were the preoperative diagnoses. All patients were women; they ranged in age from 31 to 80 years (mean, 57.6 years). The right breast was involved initially in five patients. In four, only the breast was involved (Stage I), whereas in three, the ipsilateral axillary lymph nodes (Stage II) were involved at diagnosis. According to the Working Formulation, all patients belonged to the intermediate grade and were classified as having diffuse large cell (five patients) or mixed (two patients) lymphoma. Immunophenotypic analysis revealed that all patients had B-cell lymphoma. No patients had lymphoepithelial lesions, which is the characteristic feature in categorizing a lymphoma as a mucosa-associated lymphoid tissue (MALT) lymphoma. A statistical analysis of the patient reported in the Japanese literature has divided PBL into two types: a bilateral type that affects younger women and a unilateral type that has a broad age distribution, but preponderantly occurs in older women. The age and stage at diagnosis were significant prognostic factors in predicting the survival time, but the location and size of the tumor at initial presentation, histopathologic type, terminal leukemic manifestation, and treatment modality were not.

CONCLUSIONS

This study indicates that most PBL are diffuse large cell lymphoma of B-cell phenotype and that the age and stage at diagnosis are significant prognostic factors.