The multimodality neuroimage findings in individuals with Tourette syndrome

Transcranial sonography of subcortical structures in tic/tourette disorder

Functional neuroimaging studies demonstrate disinhibition of the cortico-striatal-thalamo-cortical circuit. However, structural imaging studies revealed conflicting results, some suggesting smaller volumes of the caudate nucleus (CN) in children with Gilles de la Tourette syndrome (TS). Here we wanted to find out whether transcranial sonography (TCS) detects alterations of raphe nuclei, substantia nigra, lenticular nucleus (LN), or CN in children with Tic disorder or TS (TIC/TS).The study included 25 treatment-naive children (age: 12.2 ± 2.5 years) with a DSM-V based diagnosis of Tic disorder or TS (10 subjects), without other psychiatric or neurologic diagnosis, and 25 healthy controls (age: 12.17 ± 2.57 years), matched for age and sex. Parental rating of behavioral, emotional abnormalities, somatic complaints and social competencies of the participants were assessed using the Child Behavior Check List (CBCL/4-18R). TCS of deep brain structures was conducted through the preauricular acoustic bone windows using a 2.5-MHz phased-array ultrasound system. Fisher's exact test and Mann-Whitney-U test were used for comparisons between TIC/TS patients and healthy volunteers. The number of participants with hyperechogenic area of left CN in the TIC/TS sample was increased, compared to the healthy control group. TIC/TS patients with hyperechogenic CN showed an increased occurrence of thought- and obsessive-compulsive problems. This TCS study revealed pathologic structural changes in CN, its higher occurrence in TIC/TS compared to healthy controls and the relation to comorbidity of thought problems. Further research should focus on the molecular cause of these alterations, probably the disturbed iron metabolism.

White matter alterations predict outcomes of comprehensive behavioral intervention for tics in children with Tourette syndrome: A diffusion MRI study

AIM

Tourette syndrome (TS) is a neurodevelopmental disorder that cause sudden uncontrolled rapid and repeated vocal sounds or movements called tics. Herein, diffusion magnetic resonance imaging (dMRI) connectometry was implemented to evaluate the white matter connectivity differences among TS patients.

METHODS

A total of 63 TS and 77 typically developed (TD) individuals were enrolled in the present study. dMRI connectometry was utilized to identify differences in connectivity patterns of white matter tracts in TS patients based on quantitative anisotropy (QA). QA was compared between TS and TD patients and correlated with severity scores such as Yale Global Tic Severity Scale (YGTSS) and Premonitory Urge for Tics Scale (PUTS).

RESULTS

Higher white matter connectivity of corpus callosum and bilateral cingulum as well as lower connectivity of corticothalamic and corticostriatal pathways were evident in TS relative to TD. The baseline YGTSS motor, YGTSS total, and PUTS were negatively correlated with corticostriatal pathway, corticothalamic pathway, and bilateral cingulum integrity, respectively. The changes in tic severity scores were also positively correlated with alterations in the white matter integrity of these brain regions following behavioral therapy.

CONCLUSION

Patients with TS have several abnormalities in their white matter microstructure particularly in the cortico-striato-thalamo-cortical (CSTC) circuit, correlated with the severity of the disease. Besides, the post-behavioral therapy changes in the white matter integrity of these regions are demonstrated as response predictors.

Exploring the psychometric properties of the premonitory urge for tics scale (PUTS) and its association with psychiatric symptoms in Chinese children with tic disorders

BACKGROUND

The Premonitory Urge for Tics Scale (PUTS) is a common self-report measure of premonitory urges for patients with tic disorders. This study aims to evaluate the Chinese version of the PUTS (PUTS-C) and to explore its association with psychiatric symptoms in Chinese children diagnosed with tic disorders.

METHODS

The psychometric evaluation involved 204 outpatients with tic disorders, aged 7-16 years, who were divided into two age groups: (7-10 years, n = 103; 11-16 years, n = 95).

RESULTS

The PUTS-C demonstrated good internal consistency (McDonald'sω = 0.84) and two-week test-retest reliability (0.76). We observed a statistically significant correlation between the total PUTS-C score and various Yale Global Tic Severity Scale (YGTSS) subscales and total tic severity scores. The PUTS-C score also showed significant correlations with the Children Yale-Brown Obsessive Compulsive Scale (CY-BOCS), Screening Child Anxiety-Related Emotional Disorders (SCARED), and Children's Depression Inventory (CDI). Notably, premonitory urges independently predicted tic severity, beyond the influence of comorbid symptoms. A two-factor structure of the PUTS-C was identified in the total sample through factor analysis.

CONCLUSIONS

The PUTS-C possesses acceptable validity and good reliability. It appears that premonitory urges in Chinese patients with tic disorders are associated with obsessive-compulsive symptoms, anxiety, and depression, but can independently predict tic severity. Specific PUTS-C factors possibly related to motor and vocal tics. Future research should continue to investigate age-related differences and the association with tics and other sensory symptoms.

Pharmacological treatment of Tourette's syndrome: from the past to the future

Tourette's syndrome (TS) is a neuropsychiatric disease featuring tics and vocal tics, with a prevalence of approximately 1%, including 75% of the total number of male patients. TS seriously disturbs the patients' career, education, and life and brings a serious and unbearable psychological burden to the patients themselves and their families. At present, there are no specific clinical medications recommended for treating TS. Therefore, it is necessary to select the appropriate medication for symptomatic treatment based on the doctor's personal experience and the patient's symptoms, with the main goal of relieving symptoms, thus improving the patient's social skills and psychological problems. Here we conducted a comprehensive search on PubMed to review and organize the history and current status of the development of drug therapy for TS through a timeline format. We also systematically evaluated the effects of each drug for TS treatment to summarize the current problems and new research directions and to provide some ideas for clinical treatment.

The microstructural change of the brain and its clinical severity association in pediatric Tourette syndrome patients

BACKGROUND

Gilles de la Tourette syndrome (GTS) is a prevalent pediatric neurological disorder. Most studies point to abnormalities in the cortico-striato-thalamocortical (CSTC) circuits. Neuroimaging studies have shown GTS's extensive impact on the entire brain. However, due to participant variability and potential drug and comorbidity impact, the results are inconsistent. To mitigate the potential impact of participant heterogeneity, we excluded individuals with comorbidities or those currently undergoing medication treatments. Based on the hypothesis of abnormality within the CSTC circuit, we investigated microstructural changes in white matter using diffusion spectrum imaging (DSI). This study offers the first examination of microstructural changes in treatment-naïve pediatric patients with pure GTS using diffusion spectrum imaging.

METHODS

This single-center prospective study involved 30 patients and 30 age- and gender-matched healthy volunteers who underwent sagittal T1-weighted MRI and DSI. We analyzed generalized fractional anisotropy, mean diffusivity, axial diffusivity, and radial diffusivity.

RESULTS

No significant differences were observed in mean diffusivity and axial diffusivity values between the two groups. However, the patient group exhibited significantly higher generalized fractional anisotropy values in the right frontostriatal tract of the dorsolateral prefrontal cortex, the right frontostriatal tract of the precentral gyrus, and bilateral thalamic radiation of the dorsolateral prefrontal cortex. Additionally, the generalized fractional anisotropy value of the right frontostriatal tract of the precentral gyrus is inversely correlated with the total tic severity scores at the most severe condition.

CONCLUSION

Treatment-naïve pediatric GTS patients demonstrated increased connectivity within the CSTC circuit as per diffusion spectrum imaging, indicating possible CSTC circuit dysregulation. This finding could also suggest a compensatory change. It thus underscores the necessity of further investigation into the fundamental pathological changes in GTS. Nevertheless, the observed altered connectivity in GTS patients might serve as a potential target for therapeutic intervention.

Efficacy and Safety of Acupuncture Combined with Herbal Medicine for Children and Adolescents with Tourette Syndrome: A Systematic Review and Meta-Analysis

BACKGROUND

With the increasing prevalence of Tourette syndrome (TS), the search for alternative therapy for TS is a growing public concern. In recent years, a growing number of randomized controlled trials (RCTs) have revealed the value of acupuncture combined with herbal medicine for the treatment of TS; however, its holistic efficacy and safety remains unclear. This study aimed to evaluate the efficacy and safety of acupuncture combined with herbal medicine and to provide preliminary evidence for clinical practice.

METHODS

Eight databases were searched from their establishment to November 27, 2022, to collect RCTs of acupuncture combined with herbal medicine for TS treatment. Two researchers independently completed the study screening, data extraction, and risk of bias assessment by using NoteExpress, Excel, and Cochrane Risk of Bias Tool 2.0 (RoB 2.0). Stata 15.0 software was applied to conduct meta-analysis.

RESULTS

A total of 1,400 participants in 18 RCTs were included. Compared with the Western medicine, acupuncture combined with herbal medicine had better curative effect in the field of effective rate (risk ratio [RR] = 1.18, 95% CI: [1.12, 1.23], p < 0.05, I2 = 0%), Yale Global Tic Severity Scale (YGTSS) total score (mean difference [MD] = -3.91, 95% CI: [-5.49, -2.33], p < 0.05, I2 = 96.4%), TCM syndrome total score (MD = -2.42, 95% CI: [-3.71, -1.13], p < 0.05, I2 = 87.1%), and serum IgE negative rate (RR = 3.41, 95% CI: [1.69, 6.87], p < 0.05, I2 = 0%). Furthermore, acupuncture combined with herbal medicine reduced the adverse reaction rate (RR = 0.20, 95% CI: [0.14, 0.30], p < 0.05, I2 = 0%) and the recurrence rate (RR = 0.27, 95% CI: [0.13, 0.52], p < 0.05, I2 = 0%).

CONCLUSION

This study demonstrated the efficacy and safety of acupuncture combined with herbal medicine, which is probably a better alternative therapy for TS. However, the small number, low quality, and potential bias of the included studies caused the limitations of our results. More high-quality RCTs are required to provide supplementary evidence in the future.

Hintergrund

Mit der steigenden Prävalenz des Tourette-Syndroms (TS) ist die Suche nach alternativen Therapien für TS zunehmend zu einer Angelegenheit von öffentlichem Interesse geworden. In den vergangenen Jahren zeigte eine immer größer werdende Zahl randomisierter, kontrollierter Studien den Nutzen der Akupunktur in Kombination mit Heilkräutern; ihre ganzheitliche Wirksamkeit und Sicherheit ist jedoch weiterhin nicht klar. Mit dieser Studie sollten die Wirksamkeit und Sicherheit von Akupunktur in Kombination mit Heilkräutern beurteilt und erste Belege für die klinische Praxis gewonnen werden.

Methoden

Acht (8) Datenbanken wurden ab ihrer Einrichtung bis zum 27. November 2022 nach randomisierten kontrollierten Studien (RCTs) über Akupunktur in Kombination mit Heilkräutern zur Behandlung von TS durchsucht. Das Screening der Studien, die Datenextraktion und die Bewertung des Verzerrungsrisikos wurden von zwei unabhängigen Forschern mit Hilfe von NoteExpress, Excel und dem Cochrane Risk of Bias Tool 2.0 (RoB 2.0) durchgeführt. Die Metaanalyse erfolgte mit der Software Stata 15.0.

Ergebnisse

Insgesamt wurden 1400 Teilnehmer in 18 RCTs eingeschlossen. Im Vergleich zur westlichen Medizin (WM) hatte Akupunktur in Kombination mit Heilkräutern eine bessere kurative Wirkung in Bezug auf die Wirksamkeitsrate (RR = 1,18, 95%-KI [1,12, 1,23], p < 0,05, I2 = 0%), den Gesamtscore der Yale Global Tic Severity Scale (YGTSS) (MD = -3,91, 95%-KI [-5,49, -2,33], p < 0,05, I2 = 96,4%), den TCM-Syndrom-Gesamtscore (MD = -2,42, 95%-KI [-3,71, -1,13], p < 0,05, I2 = 87,1%) und die Serum-IgE-Negativrate (RR = 3,41, 95%-KI [1,69, 6,87], p <0,05, I2 = 0 %). Darüber hinaus verringerte Akupunktur in Kombination mit Heilkräutern die Nebenwirkungsrate (RR = 0,20, 95%-KI [0,14, 0,30], p < 0,05, I2 = 0%) sowie die Rezidivrate (RR = 0,27, 95%-KI [0,13, 0,52], p < 0,05, I2 = 0%).

Schlussfolgerung

Diese Studie belegt die Wirksamkeit und Sicherheit der Akupunktur in Kombination mit Heilkräutern, die wahrscheinlich eine bessere alternative Therapie für TS darstellt. Unsere Ergebnisse werden allerdings durch die geringe Zahl, die niedrige Qualität und die potenzielle Verzerrung der eingeschlossenen Studien eingeschränkt. Zukünftig sind weitere hochwertige RCTs erforderlich, die zusätzliche Belege liefern.

Tics and Tourette Syndrome: A Literature Review of Etiological, Clinical, and Pathophysiological Aspects

Tourette syndrome (TS) is a condition characterized by tics produced because of neuropsychiatric malfunctioning occurring in childhood, which becomes less severe in adulthood, followed by a difference in the severity of tics between two persons. TS is a diverse variable in which symptoms vary in different patients. It is associated with comorbidities like obsessive-compulsive disorder (OCD), attention deficit hyperactivity disorder (ADHD), and depression, and hampers the quality of life. Comorbid disorders must be investigated and treated as part of the clinical approach for all TS patients. Clinicians should be aware of the infrequent but serious neurological problems that can occur in these patients and recommend aggressively treating tics. Currently, there is more emphasis on symptom-based treatments by medicines, but as etiological knowledge improves, we will divert to disease-modifying medications in the future. Behavioral, pharmacological, and surgical methods can treat TS. Neuroleptics, other drugs, and behavioral therapies are the first-line options. Deep brain stimulation is evolving but has its pros and cons. The main focus of this review is on tics characteristics, how to manage and assess them, and limitations in the clinical spectrum.

Lack of Association of Group A Streptococcal Infections and Onset of Tics: European Multicenter Tics in Children Study

ObjectiveTo investigate the association between Group-A streptococcal (GAS) infections and tic incidence among unaffected children with a family history of chronic tic disorders (CTD).MethodsIn a prospective cohort study, children with no history for tics aged 3 to 10 years with a first-degree relative with CTD were recruited from the European Multicentre Tics in Children Study (EMTICS) across 16 European centres. Presence of GAS infection was assessed using throat swabs, serum Anti-streptolysin O titres (ASOT) and Anti-DNAse B (ADB) titres blinded to clinical status. GAS exposure was defined using four different definitions based on these parameters. Cox regression analyses with time-varying GAS exposure were conducted to examine the association of onset of tics and GAS exposure during follow-up. Sensitivity analyses were conducted using Cox regression and logistic regression analyses.ResultsA total of 260 children were recruited whilst one subject was found to have tic onsets before study entry and therefore was excluded. 61 children (23.6%) developed tics over an average follow-up period of 1 (SD 0.7) year. There was a strong association of sex and onset of tics, with girls having an approximately 60% lower risk of developing tics compared to boys (HR: 0.4, 95% CI 0.2-0.7). However, there was no statistical evidence to suggest an association of any of the four GAS exposure definitions with tic onset (GAS exposure definition 1: HR=0.310, 95% CI: 0.037-2.590; definition 2: HR=0.561, 95% CI: 0.219-1.436; definition 3: HR=0.853, 95% CI: 0.466-1.561; definition 4: HR=0.725, 95% CI: 0.384-1.370).ConclusionThese results do not suggest an association of GAS exposure and development of tics.Classification of EvidenceThis study provides Class I evidence that Group-A streptococcal exposure does not associate with the development of tics in children with first-degree relatives with chronic tic disorder.

A Review on P300 in Obsessive-Compulsive Disorder

Neuropsychological studies indicate the presence of cognitive changes in patients with obsessive-compulsive disorder (OCD). Indeed, OCD may be included among the dysfunctions of the frontal lobes and their connections with the limbic system, associative cortex, and basal ganglia. P300 is a positive component of the human event-related potential (ERP); it is associated with processes of encoding, identification, and categorization constituting, as a whole, the superior cortical function of information processing. Thus, P300 explores several areas that are implicated in OCD pathophysiology. Our aim is to review all relevant studies on the P300 component of the human ERP in order to recognize any significant central nervous system (CNS) correlate of cognitive dysfunction in OCD. A PubMed-based literature search resulted in 35 articles assessing P300 in OCD and reporting neurophysiological correlates of response inhibition, cortical hyperarousal, and over-focused attention. A decreased P300 amplitude was reported in both adult and pediatric patients, with a trend toward normalization after pharmacological treatment. Source localization studies disclosed an association between P300 abnormalities and the functioning of brain regions involved in the pathophysiology of OCD. Moreover, studies converge on the evidence of neurophysiological dysfunction in the frontal areas with impairment of the normal inhibitory processes in OCD. At least some of these electrophysiological correlates might reflect the obsessive thoughts and compulsions that characterize this disorder. These findings may also support cognitive-behavioral therapy (CBT) approaches on over-focused attention and inflexibility of compulsive behaviors, which should be associated to pharmacological treatment in these patients.

Immunological Dysfunction in Tourette Syndrome and Related Disorders

Chronic tic disorder and Tourette syndrome are common childhood-onset neurological diseases. However, the pathophysiology underlying these disorders is unclear, and most studies have focused on the disinhibition of the corticostriatal–thalamocortical circuit. An autoimmune dysfunction has been proposed in the pathogenetic mechanism of Tourette syndrome and related neuropsychiatric disorders such as obsessive–compulsive disorder, autism, and attention-deficit/hyperactivity disorder. This is based on evidence from animal model studies and clinical findings. Herein, we review and give an update on the clinical characteristics, clinical evidence, and genetic studies in vitro as well as animal studies regarding immune dysfunction in Tourette syndrome.