Papers by Dario Geisinger
The international tinnitus journal, 2010
A new strategy for idiopathic subjective tinnitus treatment - sound stimulation during sleep - ha... more A new strategy for idiopathic subjective tinnitus treatment - sound stimulation during sleep - has been applied. It was based on the acknowledgement that the auditory system also works during sleep, processing the incoming information. Eleven patients were stimulated every night during 6 months. The stimulus was a sound that mimetized the tinnitus and was fixed at the same tinnitus intensity, applied through an iPod. All patients decreased their tinnitus intensity in the first month of treatment (statistically significant), most of them in the first week. Tinnitus intensity continued decreasing in the following weeks; three patients presented periods of total silence.
Parkinsonism & Related Disorders, 2010
Acta Oto-laryngologica, 2012
Rise time in the estimation of the gravitational vertical in the head tilt response (HTR) test is... more Rise time in the estimation of the gravitational vertical in the head tilt response (HTR) test is increased in patients with peripheral vestibular lesions and residual chronic dizziness. Assessment of the perception of the gravitational vertical in patients with peripheral vestibular lesions through the HTR. HTR was studied in 12 patients with peripheral vestibular lesion, 8 clinically with chronic dizziness and 4 without it; 23 normal subjects were studied as control group. Two parameters of the HTR were assessed, rise time and steady-state error to characterize a dynamical system step response. The Kolmogorov-Smirnov test (alpha = 5%) was used to verify normal distribution (steady-state error, p = 0.53; rise time, p = 0.88). The three sigma ellipse was calculated for the control group. ROC curves were used to measure the sensitivity and specificity of these parameters. Rise time showed increased values in peripheral vestibular lesion patients with chronic dizziness. Two-dimensional analysis (rise time vs steady-state error) allows a better discrimination between patients with peripheral vestibular hypofunction with chronic dizziness and the rest of the studied population.
Journal of the Neurological Sciences
Acta Oto Laryngologica, May 1, 2008
The results suggest that after a sudden change in the visual input, postural adaptation is impair... more The results suggest that after a sudden change in the visual input, postural adaptation is impaired in patients with instability and central nervous system disorders (CNSD). The aim of this study was the assessment of postural adaptation, as a transient phenomenon, when sudden changes in visual perception occur in normal subjects and in patients with instability due to different CNSD. Horizontal optokinetic stimulation (40 s and suddenly stopped) was performed in 16 patients with CNSD, and also in 22 normal subjects. Measurements were made of the body center of pressure area (COP) and the body sway velocity (SV) during 10 s before and after the stop and labeling the COP trajectory. Values of COP and SV (Wilcoxon signed rank test, p=0.979 and 0.496, respectively) in normal subjects did not show any significant change before and after the stop. In 15 of the 16 assessed patients with instability associated with CNSD an increase of the COP and SV values (Wilcoxon signed test, p=0.001 and 0.004, respectively) was observed in the 10 s after the visual stop. COP labeling showed 'roaming' of the COP spatial evolution approaching the limits of stability.
International journal of audiology, Jan 2, 2015
Assess the impact of a reduction of tinnitus intensity achieved through sound stimulation during ... more Assess the impact of a reduction of tinnitus intensity achieved through sound stimulation during sleep on the improvement in the patients' quality of life. Acoustic stimuli consisted of a highly customized sound that reproduced the spectral and intensity characteristics of the tinnitus in each patient. This stimulus was uploaded into a portable electronic device and delivered through customized ear buds during sleep, every night for three months. Twelve patients with subjective idiopathic chronic tinnitus were studied. Results were assessed through: (1) the measurement in dB SPL of tinnitus intensity reduction over time; (2) the results of three psychometric tests: Tinnitus handicap inventory (THI), Tinnitus reaction questionnaire (TRQ), Tinnitus functional index (TFI); and (3) a Visual analog scale (VAS) for tinnitus annoyance. After three months of treatment, we observed an average decrease in tinnitus intensity of 14.1 dB SPL (p < 0.001), implying a 62% reduction of the pe...
... In this case, sensory functional fusion means that the vestibulo-ocular reflexes triggered ... more ... In this case, sensory functional fusion means that the vestibulo-ocular reflexes triggered by head turns and the ... at the level of the central nervous system produces retinal image instability and reweighting of the ... 3. Postural Adaptation after a Balance Rehabilitation Program (BRP ...
Acta Oto Laryngologica, May 1, 2008
The results suggest that after a sudden change in the visual input, postural adaptation is impair... more The results suggest that after a sudden change in the visual input, postural adaptation is impaired in patients with instability and central nervous system disorders (CNSD). The aim of this study was the assessment of postural adaptation, as a transient phenomenon, when sudden changes in visual perception occur in normal subjects and in patients with instability due to different CNSD. Horizontal optokinetic stimulation (40 s and suddenly stopped) was performed in 16 patients with CNSD, and also in 22 normal subjects. Measurements were made of the body center of pressure area (COP) and the body sway velocity (SV) during 10 s before and after the stop and labeling the COP trajectory. Values of COP and SV (Wilcoxon signed rank test, p=0.979 and 0.496, respectively) in normal subjects did not show any significant change before and after the stop. In 15 of the 16 assessed patients with instability associated with CNSD an increase of the COP and SV values (Wilcoxon signed test, p=0.001 and 0.004, respectively) was observed in the 10 s after the visual stop. COP labeling showed &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;roaming&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39; of the COP spatial evolution approaching the limits of stability.
Objective: Assess the impact of a reduction of tinnitus intensity achieved through sound stimulat... more Objective: Assess the impact of a reduction of tinnitus intensity achieved through sound stimulation during sleep on the improvement in the patients’ quality of life. Design: Acoustic stimuli consisted of a highly customized sound that reproduced the spectral and intensity characteristics of the tinnitus in each patient. This stimulus was uploaded into a portable electronic device and delivered through customized ear buds during sleep, every night for three months. Study sample: Twelve patients with subjective idiopathic chronic tinnitus were studied. Results: Results were assessed through: (1) the measurement in dB SPL of tinnitus intensity reduction over time; (2) the results of three psychometric tests: Tinnitus handicap inventory (THI), Tinnitus reaction questionnaire (TRQ), Tinnitus functional index (TFI); and (3) a Visual analog scale (VAS) for tinnitus annoyance. After three months of treatment, we observed an average decrease in tinnitus intensity of 14.1 dB SPL (p50.001), implying a 62% reduction of the perceived sound. This improvement was followed by a statistically significant decrease of TRQ (78%), THI (65%), and TFI (77%). Conclusions: These results suggested that the intensity reduction achieved through the protocol used in this study had a direct impact on the improvement in the patients’ quality of life.
Clinical Interventions in Aging, 2013
Poor balance is considered a challenging risk factor for falls in older adults. Therefore, innova... more Poor balance is considered a challenging risk factor for falls in older adults. Therefore, innovative interventions for balance improvement in this population are greatly needed. The aim of this study was to evaluate the effect of a new virtual-reality system (the Balance Rehabilitation Unit [BRU]) on balance, falls, and fear of falling in a population of community-dwelling older subjects with a known history of falls. In this study, 60 community-dwelling older subjects were recruited after being diagnosed with poor balance at the Falls and Fractures Clinic, Nepean Hospital (Penrith, NSW, Australia). Subjects were randomly assigned to either the BRU-training or control groups. Both groups received the usual falls prevention care. The BRU-training group attended balance training (two sessions/week for 6 weeks) using an established protocol. Change in balance parameters was assessed in the BRU-training group at the end of their 6-week training program. Both groups were assessed 9 months after their initial assessment (month 0). Adherence to the BRU-training program was 97%. Balance parameters were significantly improved in the BRU-training group (P , 0.01). This effect was also associated with a significant reduction in falls and lower levels of fear of falling (P , 0.01). Some components of balance that were improved by BRU training showed a decline after 9 months post-training. In conclusion, BRU training is an effective and well-accepted intervention to improve balance, increase confidence, and prevent falls in the elderly.
Conference proceedings : ... Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Annual Conference, 2010
In this study a simple model of the postural control system is implemented and its parameters are... more In this study a simple model of the postural control system is implemented and its parameters are adjusted to explain the differences between Parkinson's disease patient's measures and healthy young adult's measures by performing simulations of spontaneous sway with center-of-pressure traces. An optimization procedure was performed varying four parameters of the model. The best adjustment obtained was when the proportional and derivative factors where the same as for healthy young adults and noise level gain and force feedback gain varied independently. Differences in the latter parameter can be explained because of insufficient and slowed force production necessary to counteract perturbations in Parkinson's disease patients while the former may be due to noise in the sensory system that estimates the vertical deviation angle and/or perturbations in the execution of the movement.
Conference proceedings : ... Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Annual Conference, 2010
The estimation of the vertical in humans is important in everyday life although the mechanisms in... more The estimation of the vertical in humans is important in everyday life although the mechanisms involved are not completely understood yet. This paper presents two sets of experiments with normal subjects, using the same virtual reality setup, aiming to help in this understanding. First, a steady state experiment is presented, which is used to determine the gravitational vertical precision while the second, a dynamical transient response experiment, is used to find dynamic models of each subject response. Results show that the dynamic models are able to reproduce the results of the steady state experiment while having the benefits that a dynamic model brings to evaluate subjects performance.
Brazilian Journal of Otorhinolaryngology (Impresso), 2011
The description of the postural responses in Parkinson's disease patients when visual information... more The description of the postural responses in Parkinson's disease patients when visual information changes from a stable to a moving visual field analyzing the impact on balance in these patients.
Acta Oto-laryngologica, 2015
The head tilt response (HTR) test performed in a group of patients with chronic dizziness after a... more The head tilt response (HTR) test performed in a group of patients with chronic dizziness after acoustic neuroma surgery showed alterations in the gravitational vertical perception (GV). The assessment of the accuracy in the GV through the HTR test in patients with long-term balance disorders after acoustic neuroma surgery. The HTR was performed in two groups of patients that had undergone acoustic neuroma surgery: six uncompensated patients (UPs) who maintained vestibular symptoms 1 year after surgery and two compensated patients (CPs) without vestibular symptoms. Twelve healthy control adults were also tested (control group, CG). Three parameters were measured in the HTR test: steady-state error (SSE), rise time (TRS), and mean energy of the error signal per step (MEE). The UP group showed higher values for the TRS and MEE parameters compared with the CG (p &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.05) when performing the HTR test to the side of the lesion and to the contralateral side, while the SSE only showed significant higher values when the patient estimated the GV towards the side of the lesion. The two patients in the CP group did not have differences in the three parameters assessed when compared with the CG.
Acta Oto-laryngologica, 2011
This study showed that a population with benign paroxysmal positional vertigo related to mild hea... more This study showed that a population with benign paroxysmal positional vertigo related to mild head trauma (BPPVAT) was younger and more frequently presented with bilateral canalithiasis than another population with idiopathic etiology (IBPPV). In both groups, females presented a higher risk of BPPV. To compare the clinical features of a population with BPPVAT and another with IBBPV. We carried out statistical analysis of a population of 51 subjects with BPPVAT and another of 325 subjects with IBPPV, comparing age, gender, recurrence of symptoms, associated chronic dizziness (CD), and clinical presentation. Kolmogorov Smirnov test, Student&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s t test, Mann-Whitney test, 95% binomial confidence interval for proportions, chi-squared, and Fisher&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s test were used as statistical tools. A significance level of p &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.05 was considered in all cases. The population affected with BPPVAT was younger and bilateral canalithiasis was also more frequent. No differences were found in gender distribution, semicircular canals involved in the symptoms, recurrence after repositioning maneuvers, or associated CD.
Parkinsonism & Related Disorders, 2010
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Papers by Dario Geisinger