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Auditory brainstem responses (ABR) evoked by clicks allow a threshold evaluation for the high-frequency range (2-4 kHz) but not for middle and low frequencies (0.5-1 kHz). In 19 normally hearing subjects aged between 24 and 40 years. ABRs have been recorded using clicks and 0.5- and 1-kHz tone pips, with durations of 6 and 3 ms, respectively, and rise-decay times of 3 and 1.5 ms. The input signal was filtered by a passband filter of 20-5 000 Hz. Parameters of tracings elicited by the different kinds of stimuli are compared. Tone-pip ABR morphology does not show the conventional seven peaks but a single large vertex-positive wave. On the ascending branch high-frequency potentials, probably corresponding to the I, II, III and IV-V click-evoked peaks, were visible in some cases, but they rapidly disappeared as the stimulus intensity was decreased. Their 2.3-3 ms greater mean latency values are presumably related to the rise times of the stimuli employed. In terms of bioelectric generators, this large vertex-positive peak probably corresponds to the Jewett V wave. It probably represents a generalized asynchronous dendritic activity. Thus it is possible to obtain ABRs to middle- and low-frequency stimuli. Mean amplitude values of the slow wave are considerably higher than those of the Jewett V wave, but standard deviations are also larger. The positive wave has been identified in response to 1-kHz tone pips in 100% of cases at 30 dB nHL and in 52% of cases at 20 dB, while for 0.5-kHz tone pips in 73.7% of cases at 30 dB and in 57% at 20 dB. On the whole the threshold is located between 15 and 30 dB nHL.

The authors have investigated the auditory function in 35 Down's subjects, aged between 1 month and 16 years. Clinical examination revealed the occurrence of impaired nasal breathing in 18 subjects (51.4%), while otoscopy results were bilaterally normal in 12 cases (34.3%). Behavioural pure-tone audiometry yielded reliable results in 10 children (28.6%), impedance tests in 28 (80.0%), and brainstem audiometry in 29 (82.9%). A clinical and audiological follow-up has been performed in 11 cases (31.4%). Pure-tone audiometry, which may be employed in all cases only beyond 8 years of age, revealed a conductive hearing loss in 7 cases (20.0%). Impedance tests, whose usefulness is limited by the high occurrence of external ear canal stenosis, showed bilateral type A tympanograms only in 8 cases (28.6%). Stapedial reflex data were often missing, even in presence of a type A tympanogram, due to the weakness of tubaric muscles and to the presence of ossicles abnormalities. ABR has been performed in 29 cases (82.9%) and resulted to be as effective as in the normal population. It revealed a normal configuration concerning threshold and morphology in 16 cases (55.1%). The authors conclude that middle ear pathology in the Down's population is more frequent than expected on clinical basis and that objective tests are mandatory in order to obtain a reliable evaluation. While impedance tests are very sensible in detecting mild middle ear pathologies, but are not effective in threshold definition, brainstem audiometry is the choice tool in the uncooperative child, even if it cannot allow a differential diagnosis between normality and mild low-frequency conductive hearing losses.

In the present work 30 normal adult subjects (20 males, 10 females; age range 25-40 years) having no signs or symptoms of vestibular involvement were studied in order to verify whether posturographic parameters could be influenced by the static stimulation of cervical and otolithic receptors. The posturographic evaluation was carried out using a stabilometric platform (Bertec) with the subject standing and the head in one of the following positions: median position, turned left (45 degrees), turned right (45 degrees), tilted left (40 degrees), tilted right (40 degrees), with eyes both opened and closed. The data obtained indicate that wide standard deviations exist in the observed parameters and no significant changes were observed with the head turned either to the right or left nor with the head tilted in either direction. Moreover, the posturographic data obtained with eyes open were slightly reduced in comparison to those obtained with the eyes closed. One can, thus, conclude that neither cervical nor otolithic inputs influence posturographic parameters under static conditions, while visual inputs modify significantly posturographic data, except the coordinates of the foot center of pressure.

The AA. have carried out in patients affected by proved myocardial infarct, by other cardiac diseases and by muscular dystrophy the following enzymes determinations: total CPK, total LDH, SGOT, SGPT, HBDH, CPK isoenzymes by column chromatography (Mercer's method) and LDH isoenzymes either by column chromatography (Mercer's method) and by electrophoretic separation. Some results concerning the appearance of the CK-MB isoenzymes during the acute period of the myocardial infarction are described.

The rôle of syringeal feedback on the electrically elicited vocalization in chickens (Gallus gallus) was studied. The vocalization patterns elicited by stimulating the low-threshold "calling areas" in the midbrain, was examined before and after syringeal deafferentation obtained by cutting the X-XII anastomosis on either the left and right side. The results show that section of the X-XII anastomosis on the left side produces consistently a clear-cut lowering of the threshold for vocalization and an increase of the amplitude of the individual calls with no change in the repetition rate of the call sequences. All these effects are enhanced when the contralateral anastomosis is also severed. These results show that the bilateral syringeal deafferentation does not change the overall song pattern performance, that remains stereotyped both in duration and complexity, consistent with the hypothesis that, in adult birds, stable song patterns are not dependent on peripheral sources of feedback, but are ruled by a learned central control program. However the modification of vocalization threshold and amplitude suggests the hypothesis that the syringeal feedback plays an inhibitory rôle on vocalization by modulating the excitability of the central structures involved in the vocalization activity.

Thirty-two multiple sclerosis (MS) patients, 10 males and 22 females, aged between 21 and 55, underwent pure-tone audiometry and testing of auditory brainstem response (ABR). Thirteen were classified as 'definite', 12 as 'probable' and 7 as 'possible', according to the McAlpine criteria. Each ear of each patient was tested monoaurally. The most common alterations were seen in the parameters of the cross-correlation between the normal template and the template of the individual MS patient. The second most altered parameters were those concerning the V wave which was absent in most cases but, when present, rarely showed latency-amplitude values falling outside the 90% confidence limit ellipses. Test-retest replicability and stimulations with increasing numbers of stimuli per second were useful in detecting intra-individual variability of waveform characteristics. When considering all the tests performed, 88% of the 'definite', 71% of 'probable' and 64% of 'possible' MS patients' ears showed ABR abnormalities. We stress the importance of a separate evaluation of the two ears due to the frequent unilateral alterations, and of an accurate evaluation of the ABR characteristics. We conclude that brainstem audiometry is a more reliable test for detecting demyelinating processes than is usually described in the literature.

The authors have studied nasal mucociliary function and adenoid surface characteristics in a group of 86 children, aged between 4 and 10 years, divided in two groups according to the presence or absence of clinical, instrumental and röntgenographic signs of nasal obstruction due to hypertrophied adenoids. Each group was divided into 3 age-related subgroups (group I: 4-5 years; group II: 6-7 years; group III: 8-10 years). A population of normal adults was chosen both for functional and ultrastructural characteristics. Nasal mucociliary clearance velocity values were evaluated by means of the saccharine method and the surface characteristics of the adenoid tissue by means of scanning electron microscopy. The data obtained show that the nasal mucociliary function is generally reduced in children but, while in the group with poorly developed adenoids an early and progressive improvement can be observed, the children with severely hypertrophied adenoids show an impaired function up to 10 years, without age-related improvements. At almost 10 years, children with poorly developed adenoids reach normal adult clearance values. These functional data can be related to the surface characteristics of adenoid tissue. In fact, while poorly developed adenoids are characterized by a compact layer of ciliated cells, severely hypertrophied adenoids are characterized by a metaplasic epithelium, with almost complete loss of cilia. Such findings, which are probably due to the inflammatory events frequently complicating adenoid hypertrophy, could explain, together with the obstructive effects, the impairment of the nasal mucociliary clearance in childhood.

Patients with acute peripheral facial palsy (Bell's palsy) were examined by auditory brainstem response (ABR) and middle-latency response (MLR) for signs of brainstem involvement. ABR data on 30 patients indicated that wave V latencies were abnormal by greater than 3 SD in only 2 patients, 1 of whom showed abnormality contralateral to the affected side. When the criterion for abnormality was reduced to 2 SD, wave V abnormality was found in only 3 of the 30 patients. All 14 patients tested by MLR showed normal responses. These findings suggest that on the basis of evoked potential measures, brainstem involvement may not be pathognomonic of Bell's palsy.

Nasal secretions, maxillary sinus aspirates and specimens of the maxillary sinus mucosa were collected in 44 patients aged between 25 and 60 affected by mono- or bilateral chronic maxillary sinusitis, in order to establish the best sampling technique for microbiological purposes, the most frequently involved bacteria and the physiopathological mechanism underlying chronic maxillary disease. The sinusal mucosa resulted to be the most reliable sample as it reduces contamination and microbial variability. Anaerobic bacteria were isolated in nasal swab (15.6%), in maxillary sinus aspirates (30.4%) and in maxillary sinus mucosa (36.4%) of maxillary sinusitis patients. In controls anaerobic bacteria were isolated only in one nasal swab (2.3%), while they could not be isolated in maxillary sinus aspirates and in maxillary sinus mucosa. The presence of anaerobic bacteria in chronic maxillary sinusitis patients and their absence in controls seem to confirm that anaerobic microorganisms represent the main pathogenetic agents of chronic maxillary sinusitis. The possible physiopathological mechanisms underlying chronic maxillary sinus disease are finally discussed.

40-Hz event-related potentials (AERP) in response to 0.5-, 1-, 2- and 4-kHz tone pips were studied in 45 subjects (18 males and 27 females) in order to assess their reliability and threshold in normal adults and to study the effects of stimulus frequency and intensity on their latency and amplitude. In all subjects well-formed and reproducible 40-Hz AERP were detected, thus showing a good reliability of 40-Hz AERP to tone pips. The response was always detectable within 15 dB nHL intensity level and showed a sequence of positive (P1, P2 and P3) and negative (N1, N2 and N3) waves. It has also been observed that the latency of the first component following the acoustic stimulus decreased at increasing stimulus frequency and intensity, while the amplitude of the whole response increased upon increasing stimulus intensity. It can be suggested that the 40-Hz AERP to tone pips may represent a useful tool in assessing auditory threshold in the low-frequency range.

The authors have studied calcium 45 uptake and cAMP intracellular levels in normal and otosclerotic bone cell cultures after stimulation with calcitonin in the presence or absence of propranolol. The results seem to demonstrate that poststimulatory 45Ca incorporation is slightly different in normal and otosclerotic cell cultures, being slower but longer lasting in the latter. Propranolol administration markedly inhibits 45Ca uptake in normal cells, while in otosclerotic cells a massive intracellular penetration becomes evident after an initial inhibitory phase. Also cAMP intracellular levels behave differently; a marked increase, followed by a rapid decrease, can be detected in normal cells after stimulation with calcitonin, while in otosclerotic cells, the increase is slower and followed by a long lasting reduction. Adding propranolol reduces cAMP levels in normal cells, while it increases levels in otosclerotic cells. The different behavior of calcium metabolism and cAMP levels after stimulation with calcitonin, depending upon the presence or absence of propranolol, seems to indicate an alteration of the transducing mechanism between stimulus, receptor, and cellular effector in otosclerotic cells.

Primary malignant melanomas of the nasal cavity are rare, as only 400 cases have been reported to date. The present paper describes two cases recently seen in Caucasian women. The authors point out the difficult clinical diagnosis, as the symptoms are rather aspecific. From the histopathological point of view, diagnosis is easy in the melanotic cases while can show interpretating problems in the amelanotic ones, when melanoma is almost indistinguishable from other malignant neoplasms. A correlation between histological grading and prognosis was not detected, as both cases showed local recurrences within one year after surgery although they were, respectively, of epithelioid and undifferentiated type. While surgery appears to be the choice treatment of the primary lesion, the treatment of cervical metastasis is still disputable. On the whole, most authors think that the role played by radio- and mainly chemo-therapy is still limited and that cervical adenopathies should be treated by a simple lympho-adenectomy rather than by a neck dissection.

The aim of this work was to reestablish the respiratory function of the paralyzed larynx through reinnervation of the posterior cricoarytenoid (PCA) muscle by phrenic motoneurons. In nine adult cats the adductor branch of the recurrent laryngeal nerve (RLN) of one side was cut and ligated, while the abductor branch was left intact. The whole RLN was then transected lower in the neck and its distal stump anastomosed to the upper branch of the phrenic nerve. Periodical laryngoscopies under ketamine anesthesia assessed that the inspiratory abduction of the paralyzed vocal cord recovered within 45 days to 60 days in all cats. Abduction was caused by reinnervation of the PCA muscle from phrenic motoneurons, as demonstrated by electrophysiological and anatomical (retrograde transport of horseradish peroxidase) testings.

The organization of chicken mesencephalic areas from which stapedius muscle activity and vocalization can be differently elicited was studied. Our results show the existence of an area, around the mesencephalic 'calling area', from which stapedius muscle activity can be evoked independently of vocalization. Furthermore, low threshold 'vocalization loci' stimulation evokes field potentials in the stapedius-controlling area, due to the activation of stapedius-controlling neurons by vocalization neurons.

Forty heavy smokers, all males aged between 40 and 70 and affected by laryngeal cancer underwent mucociliary clearance evaluation the day before total laryngectomy, 60 days after and, in 6 of them, 5 years later. Specimens of nasal and tracheal mucosa were obtained during laryngectomy and other subsequent operations. Before total laryngectomy, no significant changes in nasal mucociliary clearance were observed in smokers and controls, and the nasal ciliary carpet was fairly well preserved. Bronchial mucociliary clearance was impaired in all patients, owing to the coexistent chronic obstructive bronchitis. 60 days after the operation, nasal mucociliary clearance was significantly improved when compared with the preoperative data and controls, owing to the increase in the endonasal temperature and humidity, and to the reduction of the nasal blood flow and disappearance of the nasal cycle, which follow tracheostomy. Surface morphologic studies show a change in the squamous epithelium of the anterior third of the nasal fossa into a columnar ciliated one. During the first 3 months after the operation, tracheobronchial mucociliary clearance increased of 50% vis-à-vis the preoperative data. During this period a clinically evident bronchial hypersecretion was observed. The reduction in nasal and tracheobronchial mucociliary clearance function which became evident 6 years after the operation, is probably due to secondary chronic infections.

The AA. have carried out researches into the results of the platelets aggregation test (PAT) on 375 people by use of the Born method; they have employed ADP and a commercial available cephalin (Thrombofax, Ortho). In the first case the parameters taken into consideration are: the minimum dose of ADP able to cause a "double wave aggregation", the slope and the maximum increase in light transmission; in the second case the parameters considered are: the latency period, the maximum speed and the maximum amplitude. The normal values, in 75 persons, are: --6 +/- 2 X 10(-7)M (min dose wor "double wave"); --15,5 +/- 4,9 UT/min (slope); -- 46,3 +/- 6,8 UT (max increase in light transmission); regarding ADP aggregation. --90 +/- 40 sec (latency period); -- 30 +/- 15 UT/min (max speed); -- 52 +/- 4,63 UT (max amplitude); relating to Thrombofax aggregation. Analyses of PAT, by parallel using both aggregating agents, have been made on 260 women undergoina an oestrogen-progestative therapy, on 25 daibetic subjects and on 15 subjects undergoing an anti-aggregation oral therapy (Ageroplas, Serono, Roma). The AA. stress on the validity of ADP as an aggregation agent in routine tests, while Trombofax has revealed itself to be not very sensitive in all the cases with hyperaggregation. However it is to be noted that use of cephalin results interesting in tests made on subjects undergoing an anti-aggregation therapy, as the PAT parameters seen proportional to the quantity of the drug given to the patient, which is just the opposite of what happens with ADP.

The effects of sex on I-III, III-V and I-V interwave intervals and I, III, V ABR waves latency values have been studied in 171 normal children born at term, 94 males and 77 females, aged between 2 and 720 days. The obtained data confirm that latency values decrease progressively with age, and show that there is a statistically significant difference in wave III and V latency values and in III-V and I-V intervals between males and females. Moreover, these differences seem to increase with age. The authors also discuss the possible underlying mechanisms and claim that even in infancy, sex-related variability should be taken into account.

The authors have studied auditory brainstem responses (ABR) in 49 preterm (Group A) and in 54 fullterm (Group B) newborns, classified according to the birthweight related to conceptional age, in order to verify the influences of this latter parameter upon ABR. In Group A newborns, 4 recording sessions were performed, while only 3 in Group B, to evaluate data obtained at the same extra-uterine age. The obtained data show that birthweight related to conceptional age seems to play a major role on the development of ABR, since no significant differences were detected between preterm and fullterm newborns, provided the birthweight was appropriate for conceptional age (ACA). On the contrary, small for conceptional age (SCA) newborns showed an abnormal ABR pattern at birth, which tended to normalize at the following recording sessions. The authors conclude that birthweight related to conceptional age represents an important factor in the development of auditory brainstem responses and that the audiological diagnosis has to be very cautious in SCA newborns, regardless if they are pre- or fullterm.

The authors report a case of left otorrhagia in a 1-year-old male infant in the presence of a mass involving the parotideal and upper cervical regions, which had appeared after an infection of the upper airways. Non-invasive techniques, such as echography and CT scan, provided useful but contradicting information. Surgery allowed us to define the diagnosis of mycotic aneurysm of the external carotid artery. The authors, after pointing out the extreme rarity of such a pathology, discuss the ethiopathogenetic theories, the clinical features, the diagnosis and the surgical and medical treatment of the disease. Concerning surgery ligation of the external carotid artery is the treatment of choice, since distally the blood flow is provided by a conspicuous collateral circle and because a possible postoperative septic dissemination is avoided.

The aim of this study was to provide the bilateral reinnervation of the posterior cricoarytenoid (PCA) muscles by the superior root of the right phrenic nerve. In six adult cats, the right phrenic root was anastomosed to the distal stump of the transected recurrent laryngeal nerve (RLN) on the same side. The RLN adductor branch was then cut and anastomosed to a nerve graft whose end was carried contralaterally and sutured to the left RLN or to the left PCA muscle. The phrenic fibers regrowing along the RLN abductor branch reinnervated the right PCA muscle and restored the inspiratory abduction of the right vocal cord in all the animals. In five of the six cats, the fibers regenerated through the RLN adductor branch and the graft reached the left PCA muscle and also restored the inspiratory opening of the larynx on the left side. Histological nerve examination revealed a fairly symmetrical distribution of the regenerated phrenic axons to the right and left PCA muscles.

25 subjects aged between 5 and 17 years, 15 females and 10 males, underwent anterior rhinomanometry. 10 of them were normal and 15 affected by velar insufficiency following adenotonsillectomy in 11 case and palatosynthesis in 4. The rhinomanometric tracing was obtained while the patient repeatedly pronounced oral vowels such as a, e, i, c, u and CVs such as ka, ga. In normal subjects intranasal pressure modifications were represented by a series of dyphasic waves with a positive-negative polarity. In the subjects with velar insufficiency the waves were almost monophasic with positive polarity. During and after the phoniatric rehabilitation, waves returned to be dyphasic together with a progressive reduction of hypernasality. While morphology of the rhinomanometric tracing can be considered a reliable index of velar function, wave's amplitude is influenced by the anatomical conditions of the nasal cavity and by the intensity with which the subject pronounces the vowels and the CVs. Rhinomanometry represents therefore an atraumatic, rapid and reliable technique, easy to perform, in order to evaluate velopharyngeal function and to monitor the increase of velar function during and after treatment.

Thirty-four children with clinically and radiologically confirmed adenoid hypertrophy underwent otoscopy, impedance tests, active anterior rhinomanometry and nasal mucociliary clearance evaluation before and 6 months after adenoidectomy. Mucociliary clearance velocity increased significantly while binasal resistances decreased after surgery. The authors conclude that mucociliary evaluation and objective measurements of nasal resistances should be added to impedance tests as indicators to adenoidectomy.

The authors have studied auditory brainstem responses (ABR) in 33 full-term newborns at 0-9, 10-30, 31-58 h, in order to evaluate changes in the first hours after birth, particularly in relation to different repetition rates and recording procedures. The data obtained show that the characteristic newborn 3-peak tracing is observed in almost all the cases at the third recording session while, at the first, wave I is absent in two-thirds of the cases. The most reliable waves at birth are waves III, V and N II, which is often present even when other vertex-positive peaks are absent. Latency values of the considered peaks tend to decrease in a statistically significant way and this decrease is almost complete at the second recording session (30 h), while V-I interval values decrease, especially when the 9 stimuli/s repetition is employed. Stimulus repetition rate affects ABR replicability and synchronization, but it hardly influences latency values. Contralaterally recorded potentials are often absent at birth and become evident 58 h later. The authors conclude that the maturational processes probably affect both peripheral and central auditory structures in the first hours after birth. In this period, increasing repetition rates seem to have a greater effect on wave replicability than on latency values.

A commercially available kit (Amino-acid TLC kit-Sibar, Perugia, Italy) for screening of plasma aminoacids inborn errors has been used as routine method for plasma newborn examinations in a mid-size clinical Laboratory. Good results were obtained by this inexpensive and simple kit.