RESUMO
PURPOSE: To report on failures related to active middle ear implants (AMEI) surgery, within a series of subjects treated at a single Implanting Center. METHODS: A retrospective review of 79 cases of implanted AMEI has been performed to report the failure ratio, the causes for the failure and the selected rehabilitative solution. The AMEI included 25 Vibrant Soundbridge® (Medel, Innsbruck, Austria), 20 as round window vibroplasty (RW-VSB) for mixed hearing loss, 5 as incus-vibroplasty for sensorineural hearing loss; 7 MET/Carina® (Cochlear, Melbourne, Australia), 2 MET for mixed and sensorineural hearing loss, 5 Carina for sensorineural hearing loss; 43 Esteem® (EnvoyMedical, St Paul, USA) for sensorineural hearing loss; 3 Maxum® (Ototronics, Texas, USA) for sensorineural hearing loss; 1 Codacs® (Cochlear, Melbourne, Australia) for severe mixed hearing loss. RESULTS: The overall complication rate affected 20% of the implanted devices, individually ranging from 6.9 to 100%. Hardware system failures were recorded in all the AMEI, ranging from 10 to 50%. The alternative auditory rehabilitation included replacement of the same system in 2 cases, use of a conventional hearing aid in 3 cases, Cochlear implantation in 4 cases and implantation in the contralateral ear in 2 cases. CONCLUSION: The present clinical experience showed that, in spite of the successful functional rate displayed by the majority of the AMEI implantees, complications may occur to a certain percentage of cases and should prompt the professionals to select alternative solutions, starting from the (re)adoption of a conventional hearing aid and ending up to Cochlear implantation.
Assuntos
Auxiliares de Audição , Perda Auditiva Condutiva-Neurossensorial Mista , Perda Auditiva Neurossensorial , Prótese Ossicular , Orelha Média/cirurgia , Perda Auditiva Neurossensorial/etiologia , Perda Auditiva Neurossensorial/cirurgia , Humanos , Estudos Retrospectivos , Janela da Cóclea/cirurgia , Resultado do TratamentoRESUMO
PURPOSE: To propose a new objective, video recording method for the classification of unilateral peripheral facial palsy (UPFP) that relies on mathematical algorithms allowing the software to recognize numerical points on the two sides of the face surface that would be indicative of facial nerve impairment without positioning of markers on the face. METHODS: Patients with UPFP of different House-Brackmann (HB) degrees ranging from II to V were evaluated after video recording during two selected facial movements (forehead frowning and smiling) using a software trained to recognize the face points as numbers. Numerical parameters in millimeters were obtained as indicative values of the shifting of the face points, of the shift differences of the two face sides and the shifting ratio between the healthy (denominator) and the affected side (numerator), i.e., the asymmetry index for the two movements. RESULTS: For each HB grade, specific asymmetry index ranges were identified with a positive correlation for shift differences and negative correlation for asymmetry indexes. CONCLUSIONS: The use of the present objective system enabled the identification of numerical ranges of asymmetry between the healthy and the affected side that were consistent with the outcome from the subjective methods currently in use.
Assuntos
Paralisia de Bell , Paralisia Facial , Face , Nervo Facial , Paralisia Facial/diagnóstico , Humanos , Gravação em VídeoRESUMO
CONCLUSION: Distribution of the receptor for epidermal growth factor (EGF-R) and of the receptor for the keratinocyte growth factor (KGF-R) in cholesteatoma was found to differ in analogy with other epithelial tissues and accordingly to epidermal differentiation and intensity of paracrine stimulation. Moreover, both EGF-R and KGF-R expression was increased, suggesting a fair correlation with aggressiveness and recurrence rate of this pathology. OBJECTIVES: To obtain information on the biological behaviour of cholesteatoma by assessing the expression and localization of EGF-R and KGF-R and correlating their tissue distribution with that of cytokeratins as a marker of differentiation. MATERIALS AND METHODS: Cholesteatoma tissue was taken during tympanoplasty surgery and processed for indirect immunofluorescence. Murine monoclonal antibodies were tested for the different growth factor receptors and pancytokeratins analysed. Fluorescence intensity signal was measured on randomly captured digital images, using FISH 2000/HI software, with a pseudocolours generation module. RESULTS: EGF-R was mostly expressed at the level of keratinocytes of the basal layer, while KGF-R signal was mainly distributed on the spinous and granular suprabasal layers that were also highly positive for cytokeratins. Significant correlation between the immunofluorescence signals was found for KGF-R and cytokeratins only, demonstrating that KGF-R expression is increased in more differentiated areas of the cholesteatoma tissue, while EGF-R is associated with proliferative and migratory portions of the lesion.
Assuntos
Colesteatoma da Orelha Média/metabolismo , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/biossíntese , Anticorpos Monoclonais , Biomarcadores/metabolismo , Colesteatoma da Orelha Média/patologia , Receptores ErbB/biossíntese , Receptores ErbB/imunologia , Técnica Indireta de Fluorescência para Anticorpo , Humanos , Queratinócitos/metabolismo , Microscopia de Fluorescência , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/imunologiaRESUMO
Vestibular schwannoma may present as a sporadic or genetically-based multi-localized benign neoplasm of the internal auditory canal and/or cerebello-pontine angle region. Multiple localization is generally regarded as genetic in origin and often affects the stato-acoustic bundle on both sides. A case of double vestibular schwannoma localized on the same stato-acoustic bundle is presented. After removal, slight histological differences were found between the two separate masses. From these findings, the possibility of a unilateral multiple localization of a vestibular schwannoma is considered plausible within the range of clinical presentation, with negative genetic features. Whether these individual masses might have an autonomous origin or a different growth pattern remains to be fully elucidated.
Assuntos
Neuroma Acústico/patologia , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
The treatment of Bell's palsy (BP), based on steroids and/or antiviral drugs, may still leave a certain percentage of affected subjects with disfiguring sequelae due to incomplete recovery. The different procedures of physical rehabilitation have not been demonstrated to play a favourable role in this disorder. The aim of the present study was to compare functional outcomes in severe cases of Bell's palsy when treated by steroids alone or by steroids accompanied by Kabat physical rehabilitation. This prospective study included 94 subjects who showed sudden facial nerve (FN) palsy with House-Brackmann grade IV or V and who were divided into two groups on the basis of the therapeutic approach: one group (a) was treated by steroids, and the other (b) received steroids in combination with physical rehabilitation. Medical treatment consisted in administration of steroids at a dosage of 60 mg per day for 15 days; physical rehabilitative treatment consisted in proprioceptive neuromuscular facilitation according to Kabat, and was administered to one of the two groups of subjects. Recovery rate, degree of recovery and time for recovery were compared between the two groups using the Mann-Whitney and univariate logistic regression statistical tests (Ward test). Kabat patients (group b) had about 20 times the odds of improving by three HB grades or more (OR = 17.73, 95% CI = 5.72 to 54.98, p < 0.001) than patients who did not receive physical treatment (group a). The mean speed of recovery in group b was the half of that recorded for group a (non-Kabat subjects). No difference was observed in the incidence of synkineses between the two groups. Steroid treatment appears to provide better and faster recovery in severe cases (HB IV and V) of BP when complemented with Kabat physical rehabilitation.
Assuntos
Paralisia de Bell/tratamento farmacológico , Paralisia de Bell/reabilitação , Glucocorticoides/uso terapêutico , Modalidades de Fisioterapia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Índice de Gravidade de Doença , Adulto JovemRESUMO
Specific ultrastructural findings have widely been described in case of obstructive nasal diseases due to congenital defects. Ciliary impairment has in particular been observed as the main pathological feature in these conditions. In this study, nasal mucosal samples from different pathologies have been collected via the "brushing" technique and analysed by transmission electron microscopy. TEM analysis was focused on specific features, such as the numerical array of peripheral and central doublets of the cilium axoneme, including eventual microtubular disarrangement; partial or total loss of inner and/or outer dynein arms; defects of radial spokes and nexin links; disorientation of the ciliary axis in closely adjacent cilia, calculating the angle between the line crossing the central microtubular core and the horizontal ciliary axis and compound cilia (CC). Statistical comparison was carried out between study and control groups. A significant incidence of organic ciliary defects was found not only in patients with inflammatory processes, but mostly in those supposed to have a long-lasting nasal respiratory disease due to mechanical stenosis in relation to septum deviation and turbinate hypertrophy. Prevalence and percentage of compound cilia were instead more related to inflammatory conditions. The "brushing" technique can be considered an easy and reliable method for the assessment of the condition of the nasal mucosa. According to the findings derived from this study, mechanical nasal obstruction seems to cause major alterations on the nasal ciliary arrangement, thus determining a functional impairment on the whole nasal function.
Assuntos
Cílios/ultraestrutura , Transtornos da Motilidade Ciliar/patologia , Obstrução Nasal/patologia , Adulto , Análise de Variância , Distribuição de Qui-Quadrado , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
Trans-cutaneous bone conduction (BC) stimulators, when coupled to the HB (BC-HB), are generally used to predict the results that could be achieved after bone conductive implant (BCI) surgery, and their performance is generally considered inferior to that provided by the definitive percutaneous system. The aim of the present study was to compare the performances between BC-HB and BCI of the same typology, when the former's sound processor is fitted in accordance to the individual auditory situation. Twenty-two patients selected for surgical application of a BCI were evaluated and the same audiological protocol was used to select the candidate and assess the final outcome. The BC-HB was properly fitted based on individual hearing loss and personal auditory targets, and tested as primary step of the protocol to obtain the most reliable predictive value. The BAHA Divino and BP100 sound processors were applied in 12 patients with conductive/mixed hearing loss (CMHL) and in 10 subjects with single sided deafness (SSD). Audiometric evaluation included the pure tone average (PTA3) threshold between 250-1000 Hz; the PTA thresholds at 2000 and 4000 Hz; intelligibility scores as percentage of word recognition (WRS) in quiet and in noise; and subjective evaluation of perceived sound quality by a visual analogue scale (VAS). Statistical evaluation with a student's t test was used for assessment of efficacy of BC-HB and BCI compared with the unaided condition. Spearman's Rho coefficient was used to confirm the reliability of the BC-HB simulation test as a predictor of definitive outcome. The results showed that the mean PTA difference between BCI and BC-HB ranged from 2.54 to 8.27 decibels in the CMHL group and from 1.27 to 3.9 decibels in the SSD group. Compared with the BC-HB, BCI showed a better WRS both in CMHL (16% in quiet and 12% in noise) and in SSD (5% in quiet and a 1% in noise) groups. Spearman's Rho coefficient, calculated for PTA, WRS in quiet and in noise and VAS in the two aided conditions, showed a significant correlation between BC-HB and BCI, between PTA and VAS and between WRS in quiet and VAS. It is possible to conclude that the headband test, when the sound processor of the selected bone conductive implant is fitted and personalised for individual hearing loss and auditory targets of the candidate, may provide highly predictive data of the definitive outcome after BCI implant surgery.
Assuntos
Condução Óssea , Auxiliares de Audição , Perda Auditiva Condutiva/cirurgia , Limiar Auditivo , Humanos , Reprodutibilidade dos Testes , Percepção da Fala , Resultado do TratamentoRESUMO
Treatment of Ménière's disease (MD) is still controversial and pressure changes transmitted to the inner ear have been reported to have effects similar to those of other non-surgical therapies. This paper reports on a clinical trial of MD patients which has been carried out using a portable piece of equipment, called Meniett, which delivers a pulsed, controlled, positive pressure to the middle ear, provided that a ventilation tube (VT) has previously been inserted. A comparison was made of the number of vertigo spells during the 2 months before treatment and during the 40-day treatment period. In addition, within this latter period a comparison was made between use of VT and use of VT + Meniett. Use of VT only had a positive effect in 90% of patients, with either absence (n = 10: 50%) or marked reduction (n = 8; 40%) in episodes of vertigo. When Meniett was also applied, stabilization of the positive effect on vertigo was registered, with a concomitant improvement in hearing threshold in 2 patients (10%). Although a longer and more reliable long-term follow-up of this treatment is needed, it is possible to propose the use of this therapeutic approach as it has been proven to induce a dramatic improvement in the symptoms affecting patients with Ménière's disease during reactivation of the disease.
Assuntos
Doença de Meniere/terapia , Ventilação da Orelha Média/instrumentação , Pressão , Adulto , Algoritmos , Audiometria de Resposta Evocada/métodos , Limiar Auditivo/fisiologia , Protocolos Clínicos , Desenho de Equipamento , Feminino , Humanos , Masculino , Doença de Meniere/diagnóstico , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Fatores de Tempo , Vertigem/diagnóstico , Vertigem/terapiaRESUMO
The surgical aspects of 34 Clarion cochlear implants, positioned during a five-year period on 31 profoundly-deaf subjects as primary (11 children, 20 adults) and revision surgery (one child, three adults) were taken into consideration. Intra- and post-operative complications related to the specific structure of this device were considered along with the benefits obtained by update of the hardware and surgical approach. A smaller thickness of the internal receiver as well as the shifting from a retro-auricular/sub-temporal (RA-ST) to an endaural-retromastoid (EA-RM) approach have contributed to a dramatic drop in post-operative complications, such as skin defect or device extrusion. Special care should, however, be taken when cochlear implantation is planned in ears with chronic otitis or its surgical sequelae. From the two revised cases (hardware failure, electrode displacement) in whom re-implantation in the same side was performed, it has been demonstrated that the helicoidal shape of the electrode carrier is not inducing any additional trauma to the cochlear structure.
Assuntos
Implante Coclear , Implantes Cocleares , Surdez/cirurgia , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Falha de Equipamento , Humanos , Complicações Intraoperatórias , Masculino , Pessoa de Meia-Idade , Otite Média/complicações , Complicações Pós-Operatórias , Reoperação , Estudos Retrospectivos , Resultado do TratamentoRESUMO
Hearing threshold has been measured in a group of patients following cochlear implantation with a Clarion device for the last eight years. The patients had received either a pre-curved carrier or the Hi-Focus I plus Electrode Positioner System (EPS). The assessment was carried out within the first post-operative week as well as at a later stage, between six and 87 months, post-operatively. Residual hearing thresholds were still measurable early after surgery in 24.5 per cent of the patients, without differences between the two different Clarion models. However, the number of subjects with measurable hearing dropped to 16.3 per cent as observed when hearing was measured at a later stage, with an equal distribution between the two groups of patients. From this study it has been possible to observe that only a limited number of patients maintain residual hearing after Clarion cochlear implantation, and that this tends to decrease further over time. Nevertheless, the performance of these patients for speech tests did not appear to be affected by deterioration of the pure-tone auditory threshold.
Assuntos
Implantes Cocleares , Perda Auditiva/prevenção & controle , Audiometria de Tons Puros , Limiar Auditivo , Estudos de Coortes , Perda Auditiva/fisiopatologia , Humanos , Período Pós-Operatório , Fatores de TempoRESUMO
Vestibular and auditory functions after glycerol intake were assessed correlated in twenty-eight patients diagnosed as menieric according to AAOO criteria. All patients had unilateral Ménière's disease confirmed by monolateral hypoacusia and labyrinthine hypofunction. Hearing thresholds were tested by tone-audiometry, according to the standard glycerol test. Variation in vestibular response were assessed comparing the VOR during the rotatory sinusoidal test as well as the caloric test, before glycerol intake and 2 hours after drug administration. Slow phase angolar velocity, directional preponderance percentile and percentile variation between basic and control observation were calculated. The audiometric glycerol test was positive in 58% of the cases. The vestibular glycerol test was positive in 30% of the cases and no correlation between and individual results hearing threshold result was found. The findings reported by other Authors regarding auditory and vestibular responses to glycerol intake were verified. Possible reasons which may account for variation with regard to reaction patterns in the acoustic and non acoustic labyrinth after glycerin administration are discussed. In the Authors' view, incoherence between vestibular and cochlear response might be linked to differences in the physiology of the fluid in the two labyrinths. In the vestibular district, glycerol might induce an early depletive effect and a later paradoxal effects due to mechanical modification of the ampulla function.
Assuntos
Glicerol , Perda Auditiva/complicações , Doença de Meniere/complicações , Audiometria de Tons Puros , Limiar Auditivo , Orelha Interna/fisiopatologia , Perda Auditiva/diagnóstico , Humanos , Doença de Meniere/fisiopatologiaRESUMO
The usefulness of cytologic diagnosis in laryngeal pathology is still controversial, also in the cytopathologist's opinion. A sampling procedure such as routine cytodiagnosis can be considered useful for both diagnosis and treatment of non-surgically related laryngeal diseases. This study was designed in order to demonstrate how cytodiagnosis can be useful in etiologic and pathogenetic diagnosis of chronic non-specific inflammatory diseases of the vocal folds. Cytologic sampling was carried out on brushing material of simple and hyperplastic laryngeal inflammations and on normal vocarfolds which were used as control. Through cytologic examination it was possible to evidence specific morphological findings which allowed differentiation of not only healthy from diseased vocal cords, but also hyperplastic from simple inflammatory processes. Moreover, the high incidence of goblet cells and cylindric squamous metaplasia in hyperplastic corditis, as well as the frequent presence of fungal involvement in the simple forms, prompted the Authors to hypothesize pathogenetic mechanisms as well as progression inducing factors of the pathologies in question.
Assuntos
Inflamação/etiologia , Doenças da Laringe/fisiopatologia , Prega Vocal/citologia , Prega Vocal/fisiopatologia , Tumor Carcinoide/diagnóstico , Tumor Carcinoide/ultraestrutura , Doença Crônica , Diagnóstico Diferencial , Humanos , Hiperplasia/diagnóstico , Doenças da Laringe/diagnóstico , Doenças da Laringe/etiologia , Metaplasia/diagnóstico , Pólipos/diagnóstico , Pólipos/ultraestruturaRESUMO
The incidence of Bell's palsy has been estimated in a health district of a major Italian city, taking also into consideration the potential risk factors that might influence the occurrence of Bell's palsy. A matched case-control was therefore designed, by collecting data from the Emergency Departments of four Hospitals belonging to the same Health District in Rome (Italy), coordinated by a tertiary referral centre University Hospital. All patients affected by Bell's palsy within the health district and four controls for each case were included. Controls were selected from other ENT patients, and were matched for hospital admission, week of disease onset, and climate conditions. Information regarding possible risk factors was collected using standardized telephone interviews. The resulting dataset was analyzed using multiple conditional logistic regression. The study group comprised 381 patients with acute, unilateral, peripheral facial palsy, clinically diagnosed as Bell's palsy observed between 1st January 2006 and 31st December 2008. The cumulative incidence of Bell's palsy was found to be 53.3/100.000/year. Among the risk factors, age was found to influence onset of Bell's palsy, with an odds ratio of 2% for each one-year increase in age, with a linear trend (95% CI = 1-3%; p = 0.005). Bell's palsy was found to occur with an annual incidence close to previous reports. Among the possible known risk factors (diabetes, pregnancy, etc.), only aging was found to play a significant role.
Assuntos
Paralisia de Bell/epidemiologia , Estudos de Casos e Controles , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Cidade de Roma/epidemiologia , Inquéritos e QuestionáriosRESUMO
Stapedectomy is known to give good results for otosclerosis. In this study, an audiometric evaluation of patients who underwent small-opening stapedotomy has been carried out at an early stage (3 and 5 days after surgery), and 1 month after surgery. At day 5 almost 60% of the patients showed a good functional result (mean residual post-op air conduction/pre-op bone conduction gap within 5 dB). While the timing of 4 kHz recovery overlapped that of the lower frequencies, recovery for 8 kHz was evident only at day 30, and was less likely to occur than for 4 kHz.
Assuntos
Audição/fisiologia , Cirurgia do Estribo/instrumentação , Audiometria de Tons Puros , Limiar Auditivo/fisiologia , Condução Óssea/fisiologia , Humanos , Microcirurgia/instrumentação , Prótese Ossicular , Otosclerose/fisiopatologia , Otosclerose/cirurgia , Cirurgia do Estribo/métodos , Fatores de TempoRESUMO
The expression of steroid receptors has been investigated in an attempt to clarify the role of steroid hormones in the proliferation and progression of acoustic neuromas. Specimens of tumours taken during translabyrinthine surgery were tested for cytosolic (c) and nuclear (n) steroid receptors. Oestrogen and progesterone receptor levels were evaluated by enzymatic immuno-assay, while androgen receptor binding levels were detected by dextran-coated charcoal method in a single-step determination. In some cases, the six point Scatchard analysis of cytosolic and nuclear androgen receptor was also performed. Threshold values were: 3 fmol/mg of proteins for cytosolic steroid receptors and 20 fmol/mg DNA for nuclear steroids, which corresponded to approximate median values of cytosolic and nuclear oestrogen and progesterone, respectively. Oestrogen and progesterone appeared to be localized more frequently in the nuclei rather than in the cytosol (70% oestrogen and progesterone positivity in the nuclei; 30% oestrogen, 40% progesterone positivity in the cytosol), while androgen receptors were preferentially localized in the cytosol (80% positivity in the cytosol; 40% positivity in the nuclei). A negative non-linear correlation between cytosolic oestrogen and cytosolic androgen receptors was found. There was a direct linear correlation between cytosolic oestrogen and nuclear oestrogen levels. A strict correlation between nuclear oestrogen and nuclear progesterone incidence was shown. Preliminary analysis of clinical data and biochemical parameters showed that cytosolic progesterone levels inversely correlated with tumour size.
Assuntos
Neuroma Acústico/química , Receptores de Esteroides/análise , Idoso , Divisão Celular , Núcleo Celular/química , Citosol/química , DNA de Neoplasias/análise , DNA de Neoplasias/genética , Progressão da Doença , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Neuroma Acústico/genética , Neuroma Acústico/patologia , Neuroma Acústico/ultraestrutura , Receptores Androgênicos/análise , Receptores Androgênicos/genética , Receptores de Estradiol/análise , Receptores de Estradiol/genética , Receptores de Estrogênio/análise , Receptores de Estrogênio/genética , Receptores de Progesterona/análise , Receptores de Progesterona/genética , Receptores de Esteroides/genéticaRESUMO
OBJECTIVE: This study aimed to evaluate the moment-to-moment auditory control of voice at an early stage after implantation with Clarion cochlear implants. STUDY DESIGN: A perceptive and electroacoustic evaluation of the voice was carried out through a digital analysis immediately after the activation of the implant, before the fitting procedure has begun. SETTING: The study was performed at the Department of Otolaryngology, University "La Sapienza" of Rome. PATIENTS: Nine profoundly deaf subjects (five post-linguistic deaf adults, two pre-linguistic deaf children and two peri-linguistic deaf subjects, one adult and one child). INTERVENTION: Surgical insertion of a Clarion cochlear device. MAIN OUTCOME MEASURES: Qualitative (short-term pitch and energy perturbation, intonation, vocal attack, quality, and intensity) and quantitative (F0, F1, F2 and F3 frequency values), under non activated (NAI) and activated (AI) condition, have been obtained. RESULTS: In the majority of patients, the perceptive evaluation under AI showed a lowering of voice intonation, a better control of voice intensity, and a reduction of nasal quality. These findings were confirmed by a significant lowering of F0 (Wicoxon non parametric test) in all cases and lowering of F1 and F2 in five cases. Additionally, a better definition of all formats in the majority of cases as well as by a parallelism of pitch and energy profile was observed. CONCLUSIONS: The Clarion cochlear implant device provided a recognizable moment-to-moment auditory control on voice and articulatory patterns. By monitoring the articulated voice during adjustment of the electrical stimulation at the first fitting session, one may be able to include these data and assist in the selection of the best rehabilitative strategy.
Assuntos
Implante Coclear , Surdez/reabilitação , Qualidade da Voz , Adolescente , Adulto , Criança , Correção de Deficiência Auditiva/instrumentação , Desenho de Equipamento , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Percepção da Altura Sonora , Percepção da FalaRESUMO
HYPOTHESIS: The differing clinical behavior of acoustic neuroma (AN) may be explained by the presence of specific biological features involved in tumorigenesis and growth. BACKGROUND: Transforming growth factor (TGF) beta1 is known to participate in the regulation of peripheral nerve tumors, modulating cell proliferation and differentiation with mechanisms different from those of glial growth factors (GGF) and fibroblastic growth factors (FGF), which are responsible for Schwann cells' mitogen activity. METHODS: Surgically removed human AN specimens were fixed in formalin and embedded in paraffin for immunohistochemistry studies. Expression and localization of TGF-beta1 in different tumor regions were assessed after incubation of paraffin sections with a mouse monoclonal anti-TGF beta1 antibody (DBA, Milan, Italy). Clinically, the time elapsed between the beginning of symptomatology and AN size as shown by preoperative computed tomography, magnetic resonance imaging, or both was calculated as rough value of growth rate, which enabled slow-growing and fast-growing ANs to be distinguished. RESULTS: Eighty-four percent of AN specimens expressed TGF-beta1 positivity at the level of the cytoplasm of the Schwann cells. TGF-beta1 reactivity was also shown in the blood vessel walls (96.15%) and the tumor capsule (80.86%). TGF-beta1 reaction appeared higher in Antoni A regions than in Antoni B regions. No significant relationship was found between TGF-beta1 positivity and AN growth rate in the two groups. CONCLUSIONS: TGF-beta1 could participate in the biological behavior of AN, particularly as an important factor of tumor growth prediction by allowing rapidly progressive or potentially recurrent tumors to be differentiated from slow-growing tumors that are unlikely to recur. The clinical course of patients with AN is currently still of little help in predicting the rate of AN growth.