Mecanismos neurofisiológicos de la rehabilitación vestibular / Neurophysiological mechanisms of vestibular rehabilitation

RESUMEN La rehabilitación vestibular es un concepto terapéutico utilizado en pacientes que presentan síntomas como vértigos y/o mareos, asociados a una afectación vestibular, además de otras manifestaciones clínicas. Este artículo busca entregar un análisis amplio de los elementos que interactúan para definir una patología, como a su vez intervenir en su compensación. Serán presentados elementos neuroanatómicos, fisiológicos y conceptuales de la rehabilitación para este tipo de pacientes con un enfoque clínico basados en la evidencia.

ABSTRACT Vestibular rehabilitation is a therapeutic concept used in patients suffering from dizziness and/or dizziness, in addition to other clinical manifestations. This article gives a broad analysis of the elements that interact to define a pathology, as well as to intervene in their compensation. Neuro anatomical, physiological and conceptual elements of rehabilitation for this type of patients will be presented with a clinical approach based on evidence.

Abmessung und Analyse der Bezugsfl(a)che von Acetabulum-Prothese-Transplantation in unterschiedlichen K(o)rperlagen / 华中科技大学学报（医学）（英德文版）

Ziel ist die Analyse der Neigungslage des Beckens im Liegen und im Stehen bzw.die Beobachtung der Stabilit(a)t der Beckenfl(a)che als Beckenfl(a)che für die Acetabulum-Prothese Transplantation. 72 Testpersonen wurden je nach Status ihres Pfannengelenks in 3 Gruppen eingeteilt:Gruppe 1 "mit gesundem Pfannengelenk", Gruppe 2 "mit Arthritis" und Gruppe 3 "nach Implantation der Hüftendoprothese". Unter dem Einsatz von 3D- Digital-Instrument wurde die Fl(a)chen-Neigung vor dem Becken jeweils im Liegen und im Stehen gemessen und die Messwerte wurden verglichen. Die Fl(a)chen-Neigungen vor dem Becken bei allen 3 Gruppen (mit gesundem Pfannengelenk/mit Arthritis/nach Operation) im Liegen sind: 6.37°± 3.70°, 6. 47°± 3.52° und 4.56°±2.39°. Im Stehen sind es 7.33°±3.08°, 6.60°±3.45° und 6.74°±3.43°. Der Fl(a)chen-Neigungsunterschied vor dem Becken im Liegen und im Stehen hat keine grosse Bedeutung (P＞0.05).Die (A)nderung der Fl(a)chen-Neigung vor dem Becken vom Liegen bis zum Stehen ist kleiner als 2.5°.Die Fl(a)che vor dem Becken (pelvic anterior plane, PAP) als Bezugsfl(a)che für Hüftpfanne-Prothese Transplantation bei klinischer Operation ist stabil und verlaβlich.

Abmessung und Analyse der Bezugsfl(a)che von Acetabulum-Prothese-Transplantation in unterschiedlichen K(o)rperlagen / 华中科技大学学报（医学）（英德文版）

Ziel ist die Analyse der Neigungslage des Beckens im Liegen und im Stehen bzw.die Beobachtung der Stabilit(a)t der Beckenfl(a)che als Beckenfl(a)che für die Acetabulum-Prothese Transplantation. 72 Testpersonen wurden je nach Status ihres Pfannengelenks in 3 Gruppen eingeteilt:Gruppe 1 "mit gesundem Pfannengelenk", Gruppe 2 "mit Arthritis" und Gruppe 3 "nach Implantation der Hüftendoprothese". Unter dem Einsatz von 3D- Digital-Instrument wurde die Fl(a)chen-Neigung vor dem Becken jeweils im Liegen und im Stehen gemessen und die Messwerte wurden verglichen. Die Fl(a)chen-Neigungen vor dem Becken bei allen 3 Gruppen (mit gesundem Pfannengelenk/mit Arthritis/nach Operation) im Liegen sind: 6.37°± 3.70°, 6. 47°± 3.52° und 4.56°±2.39°. Im Stehen sind es 7.33°±3.08°, 6.60°±3.45° und 6.74°±3.43°. Der Fl(a)chen-Neigungsunterschied vor dem Becken im Liegen und im Stehen hat keine grosse Bedeutung (P＞0.05).Die (A)nderung der Fl(a)chen-Neigung vor dem Becken vom Liegen bis zum Stehen ist kleiner als 2.5°.Die Fl(a)che vor dem Becken (pelvic anterior plane, PAP) als Bezugsfl(a)che für Hüftpfanne-Prothese Transplantation bei klinischer Operation ist stabil und verlaβlich.

Rheological characterization of composites using a vertical oscillation rheometer / 대한치과보존학회지

OBJECTIVE: The purpose of this study was to investigate the viscoelastic properties related to handling characteristics of composite resins. METHODS: A custom designed vertical oscillation rheometer (VOR) was used for rheological measurements of composites. The VOR consists of three parts: (1) a measuring unit, (2) a deformation induction unit and (3) a force detecting unit. Two medium viscous composites, Z100 and Z250 and two packable composites, P60 and SureFil were tested. The viscoelastic material function, including complex modulus E* and phase angle delta, were measured. A dynamic oscillatory test was used to evaluate the storage modulus (E'), loss modulus (E") and loss tangent (tandelta) of the composites as a function of frequency (omega) from 0.1 to 20 Hz at 23degrees C. RESULTS: The E' and E" increased with increasing frequency and showed differences in magnitude between brands. The E*s of composites at omega = 2 Hz, normalized to that of Z100, were 2.16 (Z250), 4.80 (P60) and 25.21 (SureFil). The magnitudes and patterns of the change of tandelta of composites with increasing frequency were significantly different between brands. The relationships between the complex modulus E*, the phase angle delta and the frequency omega were represented by frequency domain phasor form, E* (omega) = E*e(idelta) = E* 45 degree angle delta. CONCLUSIONS: The viscoelasticity of composites that influences handling characteristics is significant different between brands. The VOR is a relatively simple device for dynamic, mechanical analysis of high viscous dental composites. The locus of frequency domain phasor plots in a complex plane is a valuable method of representing the viscoelastic properties of composites.

The Changes of Vestibulo-Ocular Reflex after Acute Peripheral Unilateral Vestibular Loss / 대한이비인후과학회지

BACKGROUND AND OBJECTIVE: It is well known that compensation begins after acute unilateral peripheral vestibular function loss. The change of vestibulo-ocular reflex (VOR) is variable and affected by many factors. But there is no studies reported on the changes of individuals with the lapse of time. Using the rotation chair test and caloric test, we wanted to know the individual compensatory process of VOR as time progresses following an acute unilateral peripheral vestibular loss. MATERIALS AND METHODS: Subjects were patients of acute peripheral vestibular neuritis (n=19) whose nystagmus showed more than 24 hours. The follow up period was 10 weeks until the head shake nystagmus (HSN) disappeared. We measured the duration of each spontaneous nystagmus (SN) and HSN. Sinusoidal harmonic acceleration (SHA) was tested at 0.04 and at 0.08 Hz level, with the step velocity of 100 degrees per second. We also performed caloric test after HSN disappeared. RESULTS: SN and HSN each lasted 25 days and 50 days. VOR changes had an irregular pattern among individuals with gain increasing after decrement and phase lead decreasing after increment. Furthermore, the gain asymmetry was more irregular and lasted longer as well at the step velocity. Even though compensation has been reached, the caloric test revealed continuous abnormal values, which is quite different from the recovery of VOR in the rotatory test. CONCLUSION: During the early compensation period, we could recognize that the individual VOR changes recovered with a irregular pattern. On the other hand, the caloric test was not altered even after compensation.

The Effects of Dimenhydrinate on Eye Tracking Tests and VOR / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Dimenhydrinate is known to act on the vestibular system, causing vestiular suppression. But the effects related with therapeutic dosage on eye tracking tests and vestibulo-ocular reflex (VOR) are not clear yet. We performed this study to evaluate the effects of dimenhyrinate on eye tracking tests and VOR. MATERIALS AND METHODS: Twenty five healthy subjects, comprising of 12 men and 13 women between the ages of 15 and 69 (mean age=39) participated in this study. The assessment included saccade test, smooth pursuit test, optokinetic nystagmus test for eye tracking test and sinusoidal harmonic acceleration test for VOR test. Each test was performed before, and 2 hours and 4 hours after the oral intake of dimenhydrinate (therapeutic dosage: 50 mg). The subjects were kept alert by performing a calculation task and communicating with the investigator during tests. RESULTS: Analysis of results showed that latency was prolonged after 2 hours but was returned to initiae value after 4 hours. Gain was not changed in the saccade test as well as in the smooth pursuit test. Mean slow phase eye velocity (SPEV) decreased after 4 hours in optokinetic nystagmus test. Gain and phase lead decreased only at 0.01 Hz in sinusoidal harmonic acceleration test. CONCLUSION: Dimenhydrinate had minimal effects on eye tracking tests and VOR when the patient's alertness was kept during test.