Evžen Růžička

Prof. Dr. Evžen Růžička

orcid

Research Focus & Metrics

Academic Career Length

40Years (1987-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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22 December 2012 in European Journal of Neurology
Verified
Journal Article
Closed access
PDF file
ABAlfredo Berardelli
Alfredo Berardelli
GWG. K. Wenning
G. K. Wenning
Angelo AntoniniAngelo Antonini
Angelo Antonini
DBD. Berg
D. Berg
BBB. R. Bloem
B. R. Bloem
MVM. Vidailhet
M. Vidailhet

1 January 2011 in The Journal of the Acoustical Society of America
Verified
Journal Article
Closed access
JRJ. Rusz
J. Rusz
RCR. Cmejla
R. Cmejla
HRH. Ruzickova
H. Ruzickova
EREvžen Růžička
Evžen Růžička
An assessment of vocal impairment is presented for separating healthy people from persons with early untreated Parkinson’s disease (PD). This study’s main purpose was to (a) determine whether voice and speech disorder are present from early stages of PD before starting dopaminergic pharmacotherapy, (b) ascertain the specific characteristics of the PD-related vocal impairment, (c) identify PD-related acoustic signatures for the major part of traditional clinically used measurement methods with respect to their automatic assessment, and (d) design new automatic measurement methods of articulation. The varied speech data were collected from 46 Czech native speakers, 23 with PD. Subsequently, 19 representative measurements were pre-selected, and Wald sequential analysis was then applied to assess the efficiency of each measure and the extent of vocal impairment of each subject. It was found that measurement of the fundamental frequency variations applied to two selected tasks was the best method for separating healthy from PD subjects. On the basis of objective acoustic measures, statistical decision-making theory, and validation from practicing speech therapists, it has been demonstrated that 78% of early untreated PD subjects indicate some form of vocal impairment. The speech defects thus uncovered differ individually in various characteristics including phonation, articulation, and prosody.

2 February 2017 in Scientific Reports
Verified
Journal Article
Open access
PDF file
JHJan Hlavnička
Jan Hlavnička
RČRoman Čmejla
Roman Čmejla
TTTereza Tykalová
Tereza Tykalová
KSKarel Sonka
Karel Sonka
EREvžen Růžička
Evžen Růžička
JRJan Rusz
Jan Rusz
For generations, the evaluation of speech abnormalities in neurodegenerative disorders such as Parkinson’s disease (PD) has been limited to perceptual tests or user-controlled laboratory analysis based upon rather small samples of human vocalizations. Our study introduces a fully automated method that yields significant features related to respiratory deficits, dysphonia, imprecise articulation and dysrhythmia from acoustic microphone data of natural connected speech for predicting early and distinctive patterns of neurodegeneration. We compared speech recordings of 50 subjects with rapid eye movement sleep behaviour disorder (RBD), 30 newly diagnosed, untreated PD patients and 50 healthy controls, and showed that subliminal parkinsonian speech deficits can be reliably captured even in RBD patients, which are at high risk of developing PD or other synucleinopathies. Thus, automated vocal analysis should soon be able to contribute to screening and diagnostic procedures for prodromal parkinsonian neurodegeneration in natural environments.

4 March 2016 in Movement Disorders
Verified
Journal Article
Closed access
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BBBas R. Bloem
Bas R. Bloem
JMJohan Marinus
Johan Marinus
QAQuincy Almeida
Quincy Almeida
LDLee Dibble
Lee Dibble
ANAlice Nieuwboer
Alice Nieuwboer
FCfor the Movement Disorders Society Rating Scales Committee
for the Movement Disorders Society Rating Scales Committee

1 September 2013 in The Journal of the Acoustical Society of America
Verified
Journal Article
Closed access
JRJan Rusz
Jan Rusz
RCRoman Cmejla
Roman Cmejla
TTTereza Tykalova
Tereza Tykalova
HRHana Ruzickova
Hana Ruzickova
JKJiri Klempir
Jiri Klempir
EREvžen Růžička
Evžen Růžička
The purpose of this study was to analyze vowel articulation across various speaking tasks in a group of 20 early Parkinson's disease (PD) individuals prior to pharmacotherapy. Vowels were extracted from sustained phonation, sentence repetition, reading passage, and monologue. Acoustic analysis was based upon measures of the first (F1) and second (F2) formant of the vowels /a/, /i/, and /u/, vowel space area (VSA), F2i/F2u and vowel articulation index (VAI). Parkinsonian speakers manifested abnormalities in vowel articulation across F2u, VSA, F2i/F2u, and VAI in all speaking tasks except sustained phonation, compared to 15 age-matched healthy control participants. Findings suggest that sustained phonation is an inappropriate task to investigate vowel articulation in early PD. In contrast, monologue was the most sensitive in differentiating between controls and PD patients, with classification accuracy up to 80%. Measurements of vowel articulation were able to capture even minor abnormalities in speech of PD patients with no perceptible dysarthria. In conclusion, impaired vowel articulation may be considered as a possible early marker of PD. A certain type of speaking task can exert significant influence on vowel articulation. Specifically, complex tasks such as monologue are more likely to elicit articulatory deficits in parkinsonian speech, compared to other speaking tasks.

14 June 2005 in Neurology
Verified
Journal Article
Closed access
PDF file
RBR. Benecke
R. Benecke
WJW. H. Jost
W. H. Jost
PKP. Kanovsky
P. Kanovsky
EREvžen Růžička
Evžen Růžička
GCG. Comes
G. Comes
SGS. Grafe
S. Grafe
A new botulinum toxin type A free of complexing proteins (NT 201) was compared with BOTOX in patients with cervical dystonia by means of a double-blind noninferiority trial. Four hundred sixty-three patients received IM injections of 70 to 300 U of NT 201 or BOTOX and were followed up over 16 weeks. The study clearly shows that NT 201 is at least as effective and safe as BOTOX.