Topical Anesthesia Versus Submucosal Injection for Radiofrequency Turbinoplasty: Same Benefit but without Patient's Pain. A Comparative Study.

This study aimed at comparing the anesthetic efficacy of lidocaine injection versus pledgets soaked in lidocaine and epinephrine during radiosurgery of inferior turbinates. The study prospectively enrolled 120 outbound patients, who were randomly assigned to group 1 -anaesthesia with tampon soaked in lidocaine and adrenaline- or group 2 -anesthesia with tampon followed by lidocaine and adrenaline injection. The following parameters were evaluated by a visual analogue scale 1 h after surgery: pain, anxiety, chocking sensation and difficulty swallowing. Nasal obstruction, rhinorrhea, sneezing, headache and inferior turbinate size were evaluated preoperatively (T0), after 1 (T1), 2 (T2) and 3 months (T3) to surgery. The data collected were analyzed by statistic tests. Group 1 showed lesser pain than group 2 during the procedure (p < 0.01); no statistically significant differences were observed for anxiety, chocking sensation and difficulty swallowing. All patients, independently from the belonging group, significantly improved the nasal symptoms comparing T0 and T1 (p < 0.01), T2 (p < 0.01) and T3 (p < 0.01), without statistically significant differences among the groups. Radiofrequency turbinoplasty allowed to all patients to reduce the turbinates hypertrophy. Local anaesthesia with tampon allowed to obtain the same results the injective anaesthesia in term of surgical outcomes; the use of tampon allowed patients did not experience pain.

Hyperventilation-Induced Nystagmus in Acute Unilateral Vestibulopathy: A Correlation with Vestibulo-ocular Reflex Gain and Clinical Implication.

Hyperventilation-induced nystagmus test (HINT) is capable of generating a response in 77.2% of cases of acute unilateral vestibulopathy (AUVP); both nystagmus toward the affected side (excitatory pattern) and toward the healthy side (inhibitory pattern) have been described. The aim of the study is to investigate the clinical and prognostic role of the test by evaluating its correlation with vestibulo-ocular reflex (VOR) gain. We evaluated 33 AUVP patients by performing the HINT and video head impulse test (V-HIT) during the acute phase and then at 15 and 90 days after the onset of the symptoms. The correlation between the VOR gain of the affected side and test responses was evaluated first, phase by phase, and then considering the pattern shown during the first assessments. Patients with a negative HINT had a higher mean VOR gain than patients with a positive test at both 15 and 90 days. Patients who showed an inhibitory pattern at the first assessment had a continuous improvement in V-HIT performance, while patients with an initial excitatory response had a transient decrease in gain at the subsequent evaluation (P=.001). No difference between these 2 groups emerged at 90 days (P=.09). The finding of a negative HINT during the follow-up correlates with good V-HIT performance and could be an indicator of good recovery. The inhibitory pattern is associated with a subsequent improvement; and it would be indicative of compensation. but, despite this, the prognostic value of the test is limited.

Outcome of Primary Stapedotomy in 21 Consecutive Cases of Juvenile Otosclerosis.

BACKGROUND/OBJECTIVES: Otosclerosis is a relatively uncommon condition that causes conductive hearing loss in children. The preferred treatment for adults is stapedotomy, while for individuals under 18 years old, there is an ongoing discussion about the best treatment approach. Thus, the surgical procedure for the stapes in pediatric patients continues to be a subject of debate. This study aimed to evaluate the results of stapes surgery in children, trying to understand, based on our results, whether this is actually the most suitable option. METHODS: The study included 18 patients who underwent surgery between January 2013 and December 2023. The patients' ages ranged from 11 to 18 years, with an average age of 14.7. Out of the total 21 surgeries, three patients opted for bilateral surgery. Pre- and post-operative data were compared, focusing on the mean air conduction (AC) and bone conduction (BC) thresholds at frequencies of 0.5, 1, 2, and 4 kHz. Additionally, pre-operative thresholds and the post-operative air-bone gap (ABG) were examined. RESULTS: After a year, the air-bone gap was effectively reduced to 10 dB or less in 94% of the 21 cases, and to 20 dB or less in 98% of all cases. CONCLUSIONS: Our results and research in the field have consistently shown that stapedotomy, when conducted by skilled otosurgeons, is a reliable and successful procedure for a considerable number of patients. The outcomes it generates are similar to those achieved through the procedure conducted during adulthood.

Contiguous Gene Syndromes and Hearing Loss: A Clinical Report of Xq21 Deletion and Comprehensive Literature Review.

Given the crucial role of the personalized management and treatment of hearing loss (HL), etiological investigations are performed early on, and genetic analysis significantly contributes to the determination of most syndromic and nonsyndromic HL cases. Knowing hundreds of syndromic associations with HL, little comprehensive data about HL in genomic disorders due to microdeletion or microduplications of contiguous genes is available. Together with the description of a new patient with a novel 3.7 Mb deletion of the Xq21 critical locus, we propose an unreported literature review about clinical findings in patients and their family members with Xq21 deletion syndrome. We finally propose a comprehensive review of HL in contiguous gene syndromes in order to confirm the role of cytogenomic microarray analysis to investigate the etiology of unexplained HL.

Evolution of Hyperventilation-Induced Nystagmus in Acute Unilateral Vestibulopathy-Interpretative Model and Etiopathogenetic Hypotheses.

Hyperventilation induces metabolic changes that can elicit nystagmus (hyperventilation-induced nystagmus, HVIN) in various vestibular disorders, revealing vestibular imbalance and bringing out central or peripheral asymmetries. In acute unilateral vestibulopathy (AUVP, namely vestibular neuritis), hyperventilation can induce different patterns of nystagmus (excitatory, inhibitory, or negative), disclosing or modifying existing static vestibular asymmetries through its ability to invalidate compensation or increase peripheral excitability. In this context, we followed the evolutionary stages of HVIN in AUVP across 35 consecutive patients, with the goal of assessing alterations in the oculomotor pattern caused by hyperventilation over time. In the acute phase, the incidence of the excitatory pattern (and the strongly excitatory one, consisting of a reversal nystagmus evoked by hyperventilation) was significantly higher compared to the inhibitory pattern; then, a progressive reduction in the incidence of the excitatory pattern and a concomitant gradual increase in the incidence of the inhibitory one were observed in the follow-up period. Assuming the role of the ephaptic effect and the transient loss of vestibular compensation as opposing mechanisms, i.e., excitatory and inhibitory, respectively, the oculomotor pattern evoked by hyperventilation is the result of the interaction of these two factors. The data obtained allowed us to hypothesize an interpretative model regarding the pathogenetic aspects of responses evoked by hyperventilation and the etiologies of the disease: according to our hypotheses, the excitatory pattern implies a neuritic (viral) form of AUVP; instead, the inhibitory (and negative) one can be an expression of both the neuritic (viral) and vascular forms of the disease.

Italian Fast Speech Reception Threshold Test: A New Method to Investigate Adult Auditory Impairment in Noise.

INTRODUCTION: Purpose of our study was to compare two competing methods of performing bisyllabic word speech audiometry for the detection of the 50% speech reception threshold in noise (SRT50). METHODS: Classic method is performed submitting multiple word lists at a fixed signal-to-noise ratio. A newer Fast method - Italian Fast Speech Reception Threshold 50 (IFastSRT50) - is performed by means of program software with a single list of bisyllabic words and noise intensity shifting. RESULTS: Means comparison between SRT50 Classic and IFastSRT50 shows a slight significant correlation (r = 0.263; p = 0.044) and a wide significant difference: SRT50 Classic = -2.763 dB (SD = 4.1) and IFastSRT50 = -7.803 dB (SD = 2.1) (p < 0.0001). There is a high difference between the test execution time means (SRT50 Classic = 11 min, IFastSRT50 = 2 min; p < 0.0001). The correlation between test results and execution times was higher for SRT50 Classic than IFastSRT50. CONCLUSION: IFastSRT50 test is a reliable method to quickly investigate signal-to-noise ratio needed to obtain 50% of recognition scores with bisyllabic words; it allows less execution time than SRT50 Classic method and can avoid patient fatigue and other limitations of different speech discrimination tests in noise as sentences based ones.

Pediatric normative data for a novel and fast speech perception test in noise.

OBJECTIVES: Communicating in noisy settings can be difficult due to interference and environmental noise, which can impact intelligibility for those with hearing impairments and those with normal hearing threshold. Speech intelligibility is commonly assessed in audiology through speech audiometry in quiet environments. Nevertheless, this test may not effectively assess hearing challenges in noisy environments, as total silence is rare in daily activities. A recently patented method, known as the SRT50 FAST, has been developed for conducting speech audiometry in noise. This new method enables the acceleration and simplification of free field speech audiometry tests involving competition noise. This study aims to establish normative scores and standardize the SRT50 FAST method as a test for evaluating speech perception in noise in pediatric patients. METHODS: The study included 30 participants with normal hearing, consisting of 11 females and 19 males, ranging in age from 6 to 11 years. A series of speech audiometry tests were conducted to determine the speech reception threshold 50% (SRT50) in competing conditions. This included testing both the fast mode (SRT50 FAST) currently being studied and the traditional method (SRT50 CLASSIC). The SRT50, or Signal to Noise Ratio (SNR) at which 50% of speech recognition occurred, was investigated for both methods. RESULTS: The mean SRT50 FAST test score was -2.69 (SD = 3.15). The dataset exhibited a normal distribution with values ranging from 3.60 to -8.60. Since the scores are expressed in SRT, higher scores indicate poorer performance. We have established a threshold of 3.60 as the upper limit of the normal range, therefore, patients with scores above this threshold are considered to have abnormal results. CONCLUSIONS: This study aimed to establish normative data for the evaluation of free field speech in noise recognition using the SRT50 FAST method in the pediatric population. This method accurately investigates the necessary signal-to-noise ratio for achieving 50% recognition scores with bisyllabic words in a quick manner. The ultimate objective is to employ this test to identify the optimal configuration of hearing rehabilitation devices, particularly for pediatric patients with hearing aids and/or cochlear implants. Additionally, it can be used to assess pediatric patients with unilateral hearing loss.

Modified Valente Technique for Cauliflower Ear: Outcomes in Children at Two-Year Follow-Up : New Surgical Technique for Cauliflower Ear.

BACKGROUND: Cauliflower ear deformity, a common sequela of auricular trauma, presents an esthetic and reconstructive challenge. Existing surgical techniques have limitations, including complexity, donor site morbidity, and variable long-term outcomes. MATERIALS AND METHODS: In this case series, we present a novel and minimally invasive surgical approach for the correction of cauliflower ear deformity that adapts the Valente otoplasty technique; it combines cartilage debulking with helical rim release and Mustardé mattress stitches to restore ear contour and reduce the risk of recurrence. The procedural steps include bielliptic post-auricular skin and soft tissue incision, release of the cartilaginous spring, removal of excess fibrocartilaginous tissue, cartilage reshaping with suture to restore contour, and tissue redistribution to promote adherence of skin to the cartilage framework. RESULTS: Outcomes were evaluated in 7 patients (9 ears) with cauliflower ear deformity, assessing surgical duration, complications, patient satisfaction, and esthetic outcomes at two years after surgery. The mean surgical duration per patient was 52 ± 17 minutes, including 2 bilateral procedures. Follow-up at 24 months showed favorable esthetic outcome in all patients with sustained improvements in auricular contour and symmetry with neither loss of the shape nor recurrence of deformity. Patients reported high satisfaction and improved quality of life, with mean Glasgow Children Benefit Questionnaire scores of 99.3 ± 6.3. CONCLUSIONS: This technique thus demonstrated lasting correction of cauliflower ear with favorable cosmetic outcomes, low risk of complications, and high patient satisfaction. Further investigations and longer-term follow-up are warranted to validate the technique's durability and expand its application to older and more diverse patient populations. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these evidence-based medicine ratings, please refer to the Table of contents or the online Instructions to Authors www.springer.com/00266 .

Implantable hearing devices in clinical practice. Systematic review and consensus statements.

Objective: Implantable hearing devices represent a modern and innovative solution for hearing restoration. Over the years, these high-tech devices have increasingly evolved but their use in clinical practice is not universally agreed in the scientific literature. Congresses, meetings, conferences, and consensus statements to achieve international agreement have been made. This work follows this line and aims to answer unsolved questions regarding examinations, selection criteria and surgery for implantable hearing devices. Materials and methods: A Consensus Working Group was established by the Italian Society of Otorhinolaryngology. A method group performed a systematic review for each single question to identify the current best evidence on the topic and to guide a multidisciplinary panel in developing the statements. Results: Twenty-nine consensus statements were approved by the Italian Society of Otorhinolaryngology. These were associated with 4 key area subtopics regarding pre-operative tests, otological, audiological and surgical indications. Conclusions: This consensus can be considered a further step forward to establish realistic guidelines on the debated topic of implantable hearing devices.

Evaluation of Cochlear Symptoms in Migraine Patients without Vestibular Migraine and/or Ménière's Disease.

Migraine pathogenic pathways may selectively target the cochlea. A qualitative and quantitative analysis of cochlear symptoms in migraine patients without vestibular migraine and/or Méniere's disease was conducted. We examined 60 consecutive patients with history of cochlear symptoms, including fullness, tinnitus, and hearing loss. Patients were divided into two groups based on migraine history: M (migraine) and nM (no migraine). The incidence of migraine was compared to a homogeneous control group with dysfunctional and inflammatory dysphonia without cochlear symptoms. The type, time of onset, recurrence, bilaterality of symptoms, and hearing threshold were analyzed. The incidence of migraine was significantly higher (p = 0.04) in patients with cochlear symptoms than in the control group. The onset of symptoms is significantly earlier (p < 0.05) in the presence of migraine. The fullness, recurrence, and bilaterality of symptoms are associated with migraine in a statistically significant way (p < 0.05). Pure tone audiometry shows a statistically significant increase in the hearing threshold (500-1000 Hz) in group M. Based on developing findings, cochlear migraine may be considered as a novel clinical entity, like vestibular migraine. It would be the expression, in the absence of vertiginous symptoms, of a selective suffering of the anterior labyrinth by known operating mechanisms of migraine.

Practice of Monitoring Cisplatin-Induced Ototoxicity by Audiology, ENT, and Oncology Specialists: A Survey-Based Study in a Single Italian Medical Center.

Ototoxic drugs can result in hearing loss and tinnitus. Early detection of the ototoxic process can help minimize or prevent these consequences. The American Speech-Language-Hearing Association has provided guidelines for monitoring ototoxicity, whereas Italy has not yet implemented a national monitoring protocol. This study aims to assess the current state of ototoxicity monitoring in patients receiving cisplatin therapy. A self-administered survey has been used to gather information from oncologists, audiologists, and ENT specialists. The research was conducted at Santa Maria della Misericordia hospital in Perugia. Two questionnaires were administered, one to ENT/audiology specialists and another to oncology specialists. Both questionnaires were used to collect information on awareness of chemotherapy-induced ototoxicity. A comprehensive understanding of cisplatin-induced ototoxicity has been widely established (100%). The most commonly reported audiological symptoms by patients were hearing loss (100%) and tinnitus (87.5%). The majority of ENT and audiologists (93.8%) and oncologists (92.9%) expressed the need for a specific ototoxic monitoring program. However, they noted the absence of a well-defined ototoxicity monitoring protocol. A well-established and efficient ototoxic monitoring system facilitates early detection of ototoxic hearing loss and subsequent rehabilitation of inevitable hearing impairment.

Current trends on subtotal petrosectomy with cochlear implantation in recalcitrant chronic middle ear disorders.

Objective: To establish the safety and effectiveness of subtotal petrosectomy with cochlear implantation in patients affected by chronic middle ear disorders to refractory to previous surgical treatments. Methods: A multicentre, retrospective study was conducted on patients affected by recalcitrant chronic middle ear disorders who underwent cochlear implantation in combination with subtotal petrosectomy. Patients' details were collected from databases of 11 Italian tertiary referral centres. Additionally, a review of the most updated literature was carried out. Results: 55 patients were included with a mean follow-up time of 44 months. Cholesteatoma was the most common middle ear recurrent pathology and 50.9% of patients had an open cavity. 80% of patients underwent a single stage surgery. One case of explantation for device failure was reported among the 7 patients with post-operative complications. Conclusions: Subtotal petrosectomy with cochlear implantation is a benchmark for management of patients with recalcitrant chronic middle ear disorders. A single stage procedure is the most recommended strategy. Optimal follow-up is still debated. Further studies are required to investigate the role of this surgery in paediatric patients.

Skull-vibration-induced nystagmus test in patients who are candidates for intratympanic gentamicin injection.

Objective: This study aims to evaluate the utility of the skull-vibration-induced nystagmus test (SVINT) in the selection of patients with Ménière's disease (MD) for intratympanic injection of gentamicin. To date the indications for this treatment have been based only on subjective elements. Methods: A retrospective study was performed in 20 patients diagnosed with unilateral MD. SVINT were performed monthly and the evoked responses were evaluated. After 6 months, the results from patients who were candidates for gentamicin treatment (G group) were compared with those who did not need it (nG group). Correlation with Dizziness Handicap Inventory (DHI) score was evaluated. Results: 120 tests were performed. Positive SVINTs were identified in 52 cases (43.3%) and included excitatory nystagmus in 18 (34.7%), inhibitory nystagmus in 28 (53.8%), and atypical pattern in 6 cases (11.5%). A significant increase excitatory nystagmus was recorded in group G (p = 0.00001). Moreover, there was a significant increase in the DHI score in group G compared with the nG group (p < 0.0001) and in patients with evoked excitatory nystagmus. Conclusions: The finding of excitatory nystagmus during SVINTs performed on several occasions in the follow-up prior to intratympanic injection of gentamicin strengthens this therapeutic choice.

Plastic changes induced by muscle focal vibration: A possible mechanism for long-term motor improvements.

Repetitive focal vibrations can induce positive and persistent after-effects. There is still no satisfactory interpretation of the underlying mechanisms. A rationale, which can provide consistency among different results, is highly desirable to guide both the use of the application and future research. To date, interpretive models are formulated to justify the results, depending on the specific protocol adopted. Indeed, protocol parameters, such as stimulus intensity and frequency, intervention time and administration period, are variable among different studies. However, in this article, we have identified features of the protocols that may allow us to suggest a possible common mechanism underlying the effectiveness of focal vibration under different physiologic and pathologic conditions. Since repetitive focal muscle vibration induces powerful and prolonged activation of muscle proprioceptors, we hypothesize that this intense activation generates adaptive synaptic changes along sensory and motor circuits. This may lead to long-term synaptic potentiation in the central network, inducing an enhancement of the learning capability. The plastic event could increase proprioceptive discriminative ability and accuracy of the spatial reference frame and, consequently, improve motor planning and execution for different motor functions and in the presence of different motor dysfunctions. The proposed mechanism may explain the surprising and sometimes particularly rapid improvements in motor execution in healthy and diseased individuals, regardless of specific physical training. This hypothetic mechanism may require experimental evidence and could lead to extend and adapt the application of the "learning without training" paradigms to other functional and recovery needs.

Treatment of Far-Advanced Otosclerosis: Stapedotomy Plus Hearing Aids to Maximize the Recovery of Auditory Function-A Retrospective Case Series.

Far-advanced otosclerosis (FAO) refers to severe otosclerosis with scarce auditory functions. The identification of the best method to correctly listen to sound and speech has a large impact on patients' quality of life. We retrospectively analyzed the auditory function of 15 patients affected by FAO who were treated with stapedectomy plus hearing aids independent of the severity of their auditory deficit before surgery. The combination of surgery and hearing aids allowed excellent recovery of the perception of pure tone sounds and speech. Four patients, because of poor auditory thresholds, needed a cochlear implant after stapedectomy. Despite being based on a small sample of patients, our results suggest that stapedotomy plus hearing aids could improve the auditory capacities of patients with FAO independent of their auditory thresholds at T0. The careful selection of patients is fundamental to obtain the best outcomes.

Induction and Cancellation of Self-Motion Misperception by Asymmetric Rotation in the Light.

Asymmetrical sinusoidal whole-body rotation sequences with half-cycles at different velocities induce self-motion misperception. This is due to an adaptive process of the vestibular system that progressively reduces the perception of slow motion and increases that of fast motion. It was found that perceptual responses were conditioned by four previous cycles of asymmetric rotation in the dark, as the perception of self-motion during slow and fast rotations remained altered for several minutes. Surprisingly, this conditioned misperception remained even when asymmetric stimulation was performed in the light, a state in which vision completely cancels out the perceptual error. This suggests that vision is unable to cancel the misadaptation in the vestibular system but corrects it downstream in the central perceptual processing. Interestingly, the internal vestibular perceptual misperception can be cancelled by a sequence of asymmetric rotations with fast/slow half-cycles in a direction opposite to that of the conditioning asymmetric rotations.

Early cochlear implantation in prelingual profound hearing loss in Italy, analyzed by means of a social media survey.

Objective: To assess newborn hearing screening (NHS) impact on timing of cochlear implant (CI) surgery of patients with prelingual bilateral profound hearing impairment (BPHI), in order to evaluate whether the NHS ultimately serves the needs of the target population in Italy. Methods: An online questionnaire was created to survey subjects affected by prelingual BPHL born between 1990 and 2018. Questions focused on age at BPHI diagnosis, first and second CI surgery (if performed), and the region in which the surgery was performed. The survey was distributed to potential participants via social media communities used by hearing impaired people or their family members for sharing advice and offering support. Responses were analyzed using descriptive statistics. Results: Among the 318 respondents who completed the questionnaire, 276 (87%) reported having chosen CI surgery, 2/3 of them bilaterally. In the vast majority (97%) of cases the CI is used on a daily basis. Most of the people residing in the center (65%) and southern Italy (71%) had to move from their region of residence to perform the surgery. Late CI surgery was associated with failure to perform NHS (p = 0.007), birth before 2011 (p = 0.009), definitive diagnosis of BPHI after 6 months of life (p = 0.002), and progressive hearing impairment (p < 0.001). Conclusion: The worldwide scientific approval of the NHS as the current best opportunity for early diagnosis and CI treatment for prelingual BPHI is confirmed by what patients and families reported via the online questionnaire used for this study. In recent years, early bilateral cochlear implantation has become increasingly available in Italy, but late diagnosis, progressive hearing loss, failure to perform the NHS and lack of follow-up are still open questions. A large proportion of families had to move from the region of residence to have their child undergo CI surgery, revealing inequalities in terms of geographical disparities. Social media has proved to be a valuable, fast and inexpensive tool for gathering information on the effectiveness of health prevention programs, involving a large sample of individuals in a short amount of time.

Critical Issues in the Management of Newborn Hearing Screening in the Time of COVID-19 in Umbria, Italy.

Hearing impairment is the most frequent of the sensorial defects in humans, and if not treated promptly, can severely impair cognitive and spoken language skills. For this reason, a universal newborn hearing screening (UNHS) has been established. The purpose of our study is to examine, by means of a retrospective analysis, the results of the UNHS program in the Umbria region during the spread of COVID-19 (2020-2021), comparing the same data from the years 2011-2012, to understand if the program has improved. Our study has shown how the coverage rate of well born babies' (WB) screening has significantly increased to currently meet the JCIH benchmark. The percentage of WB referrals significantly decreased in 2020-2021, another indicator of the screening program's greater efficiency in Umbria. However, a critical issue has emerged: the percentage of those lost to follow-up is greater than 30%, well above the benchmark. As far as the COVID-19 pandemic has certainly had a significant impact, it is necessary to carefully monitor those who do not access the diagnostic level. To emphasize the importance of a proper screening program, it will be helpful to strengthen the computerized data collection system and create an information network between audiologists, pediatricians and families.

Persistent Postural Perceptual Dizziness in Episodic Vestibular Disorders.

Benign Paroxysmal Positional Vertigo (BPPV), Vestibular Migraine (VM), and Meniere Disease (MD) are among the most common episodic vestibulopathies. Persistent Postural Perceptual Dizziness (PPPD) is a chronic functional vestibular disorder that can arise in patients suffering from one or more of these conditions. We analyzed the role of these vestibular disorders as single or multiple associated comorbidities and as a precipitating condition for PPPD. A total of 376 patients suffering from dizziness with a known history of single or multiple vestibular disorders were preliminarily evaluated. We conducted a careful anamnesis to determine whether the reported dizziness could meet the diagnostic criteria for PPPD. PPPD was diagnosed in 24 cases; its incidence in patients with history of a single comorbidity or multiple vestibular comorbidities was 3.9% and 22.4%, respectively. BPPV, VM, and MD were identified as a precipitating condition in 2.34%, 16.45%, and 3.92%, respectively. BPPV constituted a precipitating condition mainly at the first episode. We observed that the presence of multiple vestibular comorbidities (BPPV, VM, and MD) in patients' clinical history increased the risk of PPPD. VM plays a significant role in representing a precipitating condition for PPPD, both when present individually or in association with the other vestibular disorders.

Adaptive perceptual responses to asymmetric rotation for testing otolithic function.

This study aimed to test the role of the otolithic system in self-motion perception by examining adaptive responses to asymmetric off-axis vertical rotation. Self-movement perception was examined after a conditioning procedure consisting of prolonged asymmetric sinusoidal yaw rotation of the head on a stationary body with hemicycle faster than the other hemicycle. This asymmetric velocity rotation results in a cumulative error in spatial self-motion perception in the upright position that persists over time. Head yaw rotation conditioning was performed in different head positions: in the upright position to activate semicircular canals and in the supine and prone positions to activate both semicircular canals and otoliths with the phase of otolithic stimulation reversed with respect to activation of the semicircular canals. The asymmetric conditioning influenced the cumulative error induced by four asymmetric cycles of whole-body vertical axis yaw rotation. The magnitude of this error depended on the orientation of the head during the conditioning. The error increased by 50% after upright position conditioning, by 100% in the supine position, and decreased by 30% in the prone position. The enhancement and reduction of the perceptual error are attributed to otolithic modulation because of gravity influence of the otoliths during the conditioning procedure in supine and prone positions. These findings indicate that asymmetric velocity otolithic activation induces adaptive perceptual errors such as those induced by semicircular canals alone, and this adaptation may be useful in testing dynamic otolithic perceptual responses under different conditions of vestibular dysfunction.