Increased tissue copper and manganese content in the lentiform nucleus in primary adult-onset dystonia

Enlarged Area of Mesencephalic Iron Deposits in Adults Who Stutter

PURPOSE

Childhood onset speech fluency disorder (stuttering) is possibly related to dopaminergic dysfunction. Mesencephalic hyperechogenicity (ME) detected by transcranial ultrasound (TCS) might be seen as an indirect marker of dopaminergic dysfunction. We here determined whether adults who stutter since childhood (AWS) show ME.

METHODS

We performed TCS in ten AWS and ten matched adults who never stuttered. We also assessed motor performance in finger tapping and in the 25 Foot Walking test.

RESULTS

Compared to controls, AWS showed enlarged ME on either side. Finger tapping was slower in AWS. Walking cadence, i.e., the ratio of number of steps by time, tended to be higher in AWS than in control participants.

DISCUSSION

The results demonstrate a motor deficit in AWS linked to dopaminergic dysfunction and extending beyond speech. Since iron deposits evolve in childhood and shrink thereafter, ME might serve as an easily quantifiable biomarker helping to predict the risk of persistency in children who stutter.

Transcranial Sonography versus CT for Postoperative Monitoring After Decompressive Craniectomy

BACKGROUND AND PURPOSE

Computed tomography (CT) is the actual gold standard diagnostic tool for monitoring patients after decompressive craniectomy. It is validated and provides a wide number of information. However, it takes time, expensive, and requires patient transportation. Transcranial sonography (TCS) could represent an alternative diagnostic tool in these patients. The aim of this study is to compare TCS versus CT scan after decompressive craniectomy in terms of diagnosing complications and costs evaluation.

METHODS

We prospectively enrolled 10 craniectomized patients who were monitored with sonography and CT. Ventricular measurements and possible complications were evaluated by two independent observers. The two methods were compared using Fisher's exact test and Spearman's Rho coefficient. A costs analysis was also conducted.

RESULTS

A good correlation coefficient (ρ) between CT and TCS was found for frontal horn dimensions (ρ .9929), median cella (ρ .9516), and third ventricle (ρ .8989). All results were statistically significant (P < .0001) and Bland-Altman plots showed no systemic biases. Fisher's exact test showed no statistically significant differences between TCS and CT for all the studied predefined complications. Cost analysis showed a 68% cost reduction in favor of TCS.

CONCLUSIONS

TCS could be a reliable alternative diagnostic tool for major complications in patients undergoing decompressive craniectomy. It could limit the number of CT scans per patient overcoming several limitations, such as costs, radiation exposure, and need to move the patient.

Transcranial sonography changes in heterozygotic carriers of the ATP7B gene

PURPOSE

Wilson's disease (WD) is an autosomal recessive disorder of ATP7B gene leading to impaired copper metabolism. Brain imaging, such as magnetic resonance (MR) and transcranial sonography (TCS) in WD patients, shows changes mostly in the basal ganglia. Heterozygotic carriers of one faulty ATP7B gene should not exhibit symptoms of WD, but one in three heterozygotes has copper metabolism abnormalities. This study examined heterozygote ATP7B mutation carriers using TCS to assess any basal ganglia changes compared with healthy controls.

METHODS

Heterozygote carriers and healthy volunteers underwent the same standard MR and TCS imaging protocols. Heterozygotes were followed for 5 years and monitored for the development of neurological symptoms.

RESULTS

The study assessed 34 heterozygotes (21 women), with mean age of 43 years (range of 18 to 74 years) and 18 healthy controls (13 women), with mean age of 47 years (range of 20 to 73 years). Bilateral lenticular nucleus (LN) hyperechogenicity was found in 25 heterozygotes, but none of the controls (p < 0.001). Bilateral substantia nigra (SN) hyperechogenicity was found in 8 heterozygotes and one control; another 3 heterozygotes had unilateral SN hyperechogenicity (p = 0.039 for the right; p = 0.176 for the left). Heterozygotes had larger SN area on both sides compared with controls (p = 0.005 right; p = 0.008 left).

CONCLUSIONS

SN and LN hyperechogenicity were more frequent in heterozygotes than in controls, probably due to copper accumulation, but it remains unknown if this predisposes to brain neurodegeneration.

Transcranial B-Mode Sonography in Movement Disorders

Applying a 2-4MHz probe at the temporal bone window transcranial B-mode sonography (TCS) enables the depiction of the brain parenchyma through the intact skull. Meanwhile it has been applied for the diagnosis and the differential diagnosis of movement disorders for decades. In the first part of this chapter, we summarize the technical requirements and describe the ultrasound method for optimal TCS examination. Imaging planes and the relevant structures are explained in detail. In the second part of the chapter, we focus on the role of substantia nigra hyperechogenicity for the diagnosis of Parkinson's disease (PD) and prodromal PD. In this part, we also mention the role of TCS in atypical and secondary Parkinsonian syndromes and other movement disorders. Summarizing all these information we explain how TCS can be helpful for the differential diagnosis of movement disorders. The current data show that TCS is an easily applicable and economic imaging method which can be used as an additional tool for the diagnosis of PD with a high sensitivity (>85%), specificity (>80%) and inter-rater reliability (>84%) as well as for the differential diagnosis of movement disorders. Lately, TCS has also been utilized in further areas such as the detection of individuals at risk for PD or the determination of electrode localization in patients with deep brain stimulation. An insufficient temporal bone window especially in the elderly and the necessity of an experienced investigator are limitations of this method.

Intraoperative Transcranial Sonography for Detection of Contralateral Hematoma Volume Change in Patients with Traumatic Brain Injury

The authors present two clinical cases, in which intraoperative transcranial sonography (TCS) was used to detect a change in contralateral hematoma volume. A 51-year-old female and a 5-year-old male underwent osteoplastic craniotomy for epidural hematoma removal. Scant contralateral hematoma was evident by preoperative computed tomography in both patients. Intraoperative TCS was used to detect changes in contralateral hematomas. After observing a volume change in one case, a second operation was performed immediately. Based in this experience, the authors recommend intraoperative TCS for the detection of contralateral hematoma volume changes.

Sonographic Alteration of Basal Ganglia in Different Forms of Primary Focal Dystonia: A Cross-sectional Study

Background:

Few studies have addressed whether abnormalities in the lenticular nucleus (LN) are characteristic transcranial sonography (TCS) echo features in patients with primary dystonia. This study aimed to explore alterations in the basal ganglia in different forms of primary focal dystonia.

Methods:

cross-sectional observational study was performed between December 2013 and December 2014 in 80 patients with different forms of primary focal dystonia and 55 neurologically normal control subjects. TCS was performed in patients and control subjects. Multiple comparisons of multiple rates were used to compare LN hyperechogenicity ratios between control and patient groups.

Results:

Thirteen individuals were excluded due to poor temporal bone windows, and two subjects were excluded due to disagreement in evaluation by sonologists. Totally, 70 patients (cervical dystonia, n = 30; blepharospasm, n = 30; oromandibular dystonia, n = 10) and 50 normal controls were included in the final analysis. LN hyperechogenicity was observed in 51% (36/70) of patients with primary focal dystonia, compared with 12% (6/50) of controls (P < 0.001). Substantia nigra hyperechogenicity did not differ between the two groups. LN hyperechogenicity was observed in 73% (22/30) of patients with cervical dystonia, a greater prevalence than in patients with blepharospasm (33%, 10/30, P = 0.002) and oromandibular dystonia (40%, 4/10, P = 0.126). LN hyperechogenicity was more frequently observed in patients with cervical dystonia compared with controls (73% vs. 12%, P < 0.001); however, no significant difference was detected in patients with blepharospasm (33% vs. 12%, P = 0.021) or oromandibular dystonia (40% vs. 12%, P = 0.088).

Conclusions:

LN hyperechogenicity is more frequently observed in patients with primary focal dystonia than in controls. It does not appear to be a characteristic TCS echo feature in patients with blepharospasm or oromandibular dystonia.

Lenticular nucleus hyperechogenicity in Wilson's disease reflects local copper, but not iron accumulation

In patients with Wilson's disease (WD) transcranial brain sonography typically reveals areas of increased echogenicity (hyperechogenicity) of the lenticular nucleus (LN). Correlation with T2-hypointensity on magnetic resonance images suggested that LN hyperechogenicity in WD is caused by trace metal accumulation. Accumulation of both, copper and iron, in the brain of WD patients has been reported. The present study was designed to elucidate whether LN hyperechogenicity in WD reflects accumulation of copper or iron. Post-mortem brains of 15 WD patients and one non-WD subject were studied with ultrasonography in an investigator-blinded fashion. LN hyperechogenicity was measured planimetrically by manual tracing as well as using digitized image analysis. The putaminal copper content was determined in samples of 11 WD brains and the non-WD brains using inductively coupled plasma mass spectrometry, and iron content was assessed using flame atomic absorption spectroscopy. LN was normal on ultrasonography only in the non-WD brain, but abnormal (hyperechogenic) in all WD brains. Digitized image analysis measures of LN hyperechogenicity and, by trend, manual measures correlated with putaminal copper content (Pearson test; digitized: r = 0.77, p = 0.04; manual: r = 0.57, p = 0.051) but not with iron content (each, p > 0.18). LN hyperechogenicity measures were unrelated to age at death of patients, age at onset of WD, WD duration, age of brain specimen, serum copper or serum ceruloplasmin (each, p > 0.1). We conclude that LN hyperechogenicity in WD reflects copper, but not iron accumulation. Further studies are warranted to elucidate the use of transcranial brain sonography for monitoring therapeutic effects of chelating agents in WD patients.

Transcranial sonography in obsessive-compulsive disorder

There is convergent evidence that basal ganglia structures are involved in the pathogenesis of obsessive-compulsive disorder (OCD). It has been also assumed that OCD is caused by a central serotonergic dysfunction. Transcranial sonography (TCS) has become a reliable, sensitive and non-invasive diagnostic tool concerning the evaluation of extrapyramidal movement disorders. This study used TCS to examine the alterations in different parenchymal regions, especially concerning serotonergic brainstem raphe nuclei as well as basal ganglia in OCD. Thirty-one OCD patients were compared with 31 matched healthy controls. Echogenecities were investigated according to the examination protocol for extrapyramidal disorders using a Siemens Sonoline(®) Elegra system. Obsessive-compulsive disorder patients showed reduced echogenity of the serotonergic brainstem raphe nuclei (32.3%) compared with healthy controls (16.1%). In nine OCD-patients (31%), but only in 2 control subjects (6.2%), a hyperechogenicity of the caudate nucleus was found. Patients with OCD significantly more often reveal a hypoechogenic brainstem raphe possibly reflecting altered serotonergic neurons there and a hyperechogenicity of caudate nucleus indicating structural or molecular cell changes. Further research is warranted to examine, whether TCS is useful in order to classify OCD and its subtypes.

Usefulness of transcranial echography in patients with decompressive craniectomy: a comparison with computed tomography scan

OBJECTIVE

To assess the agreement between computed tomography and transcranial sonography in patients after decompressive craniectomy.

DESIGN

Prospective study.

SETTING

The medical intensive care unit of a university-affiliated teaching hospital.

PATIENTS

Thirty head-injured patients consecutively admitted to the intensive care unit of "A. Gemelli" Hospital who underwent decompressive craniectomy were studied. Immediately before brain cranial tomography, transcranial ultrasonography was performed.

MEASUREMENTS AND MAIN RESULTS

The mean difference between computed tomography and echography in measuring the dislocation of midline structures was 0.3 ± 1.6 mm (95% confidence interval 0.2-0.9 mm; intraclass correlation coefficient, 0.979; p < .01). An excellent correlation was found between computed tomography and transcranial sonography in assessing volumes of hyperdense lesions (intraclass correlation coefficient, 0.993; p < .01). Lesions that appear hypodense on computed tomography scan were divided in ischemic and late hemorrhagic. No ischemic lesion was localized on echography; a poor correlation was found between computed tomography and echography in assessing the volume of late hemorrhagic lesions (intraclass correlation coefficient, 0.151; p = .53). A quite good correlation between transcranial ultrasonography and computed tomography was found in measuring lateral ventricles width (intraclass correlation coefficient, 0.967; p < .01). Sensitivity and specificity of transcranial ultrasonography in comparison with computed tomography to detect the position of intracranial pressure catheter was 100% and 78%.

CONCLUSIONS

Echography may be a valid option to computed tomography in patients with decompressive craniectomy to assess the size of acute hemorrhagic lesions, to measure midline structures and the width of lateral ventricles, and to visualize the tip of the ventricular catheter.

Depression in patients with Huntington disease correlates with alterations of the brain stem raphe depicted by transcranial sonography

BACKGROUND

Transcranial sonography (TCS) has become a new diagnostic tool in the evaluation of extrapyramidal disorders. Studies of TCS report alterations of the mesencephalic raphe in patients with depression. The aim of this study was to evaluate TCS findings in patients with Huntington disease in correlation with their neurologic and psychiatric status.

METHODS

We recruited patients with genetically confirmed Huntington disease. The neurological and psychiatric status of participants was assessed by independent physicians. Echogenicities were investigated according to examination protocol for extrapyramidal disorders using a Siemens Sonoline Elegra system. The sonography examiner was blinded for clinical data.

RESULTS

We included 39 patients in our study; 21 patients (53.8%) showed symptoms of depression at the time of evaluation and, of those, 15 (71.4%) had hypoechogenic raphe structures. Thirty patients (76.9%) had a history of depressive episodes, 19 (63.3%) of them with hypoechogenic raphe structures. All 9 patients without a history of depressive episodes showed normal echogenicity of raphe structures (sensitivity 63.3%, specificity 100%). Twelve (70.6%) of the 17 patients with Huntington disease who showed psychiatric disturbances prior to the occurrence of motor symptoms exhibited pathological raphe echogenicity (sensitivity 70.6%, specificity 68.2%).

LIMITATIONS

Most of the patients were taking antichoreatic medication, which particularly influences neurologic status. Thus, a meaningful interpretation of the correlation between TCS findings and neurologic features was limited.

CONCLUSION

As a novel finding, a relation between mesencephalic raphe echogenicity and depressive state could be identified in patients with Huntington disease. An alteration of the serotonergic brain stem raphe might be involved in the pathogenesis of depression in these patients.

Distinct basal ganglia hyperechogenicity in idiopathic basal ganglia calcification

We report a 67-year-old patient with idiopathic basal ganglia calcification (IBGC). He presented with progressive cognitive impairment, frontal lobe dysfunction, mild leg spasticity, and levodopa (L-dopa)-responsive parkinsonism. Transcranial sonography (TCS) revealed marked hyperechogenicity of the basal ganglia and periventricular spaces bilaterally. The detected signal alterations showed a fairly symmetric distribution and corresponded to the hyperintense calcifications depicted on the computer tomography brain scan. The combination of symmetric hyperechogenic areas adjacent to the lateral ventricles and of the basal ganglia may serve as an imaging marker characteristic of IBGC. Hyperechogenicity due to extended basal ganglia calcification as presented here is distinct from the pattern of hyperechogenicity caused by heavy metal accumulation, which is described to be less striking. In addition to atypical parkinsonian syndromes such as progressive supranuclear palsy and multiple system atrophy, IBGC is thus another differential diagnosis of parkinsonism with basal ganglia hyperechogenicity.

Clinical neuroimaging and electrophysiological assessment of three DYT6 dystonia families

The purpose of the study was to delineate clinical and electrophysiological characteristics as well as laryngoscopical and transcranial ultrasound (TCS) findings in THAP1 mutation carriers (MutC). According to recent genetic studies, DYT6 (THAP1) gene mutations are an important cause of primary early-onset dystonia. In contrast to DYT1 mutations, THAP1 mutations are associated with primary early-onset segmental or generalised dystonia frequently involving the craniocervical region and the larynx. Blood samples from twelve individuals of three German families with DYT6 positive index cases were obtained to test for THAP1 mutations. Eight THAP1 MutC were identified. Of these, six (three symptomatic and three asymptomatic) THAP1 MutC could be clinically evaluated. Laryngoscopy was performed to evaluate laryngeal dysfunction in patients. Brainstem echogenicity was investigated in all MutC using TCS. Two of the patients had undergone bilateral pallidal DBS. In all three symptomatic MutC, early-onset laryngeal dystonia was a prominent feature. Laryngeal assessment demonstrated adductor-type dystonia in all of them. On clinical examination, the three asymptomatic MutC also showed subtle signs of focal or segmental dystonia. TCS revealed increased substantia nigra (SN) hyperechogenicity in all MutC. Intraoperative microelectrode recordings under general anesthesia in two of the patients showed no difference between THAP1 and previously operated DYT1 MutC. The presence of spasmodic dysphonia in patients with young-onset segmental or generalised dystonia is a hallmark of DYT6 dystonia. SN hyperechogenicity on TCS may represent an endophenotype in these patients. Pallidal DBS in two patients was unsatisfactory.

Nonprimary dystonias

Dystonias can be classified as primary or secondary, as dystonia-plus syndromes, and as heredodegenerative dystonias. Their prevalence is difficult to determine. In our experience 80-90% of all dystonias are primary. About 20-30% of those have a genetic background; 10-20% are secondary, with tardive dystonia and dystonia in cerebral palsy being the most common forms. If dystonia in spastic conditions is accepted as secondary dystonia, this is the most common form of all dystonia. In primary dystonias, the dystonic movements are the only symptoms. In secondary dystonias, dystonic movements result from exogenous processes directly or indirectly affecting brain parenchyma. They may be caused by focal and diffuse brain damage, drugs, chemical agents, physical interactions with the central nervous system, and indirect central nervous system effects. Dystonia-plus syndromes describe brain parenchyma processes producing predominantly dystonia together with other movement disorders. They include dopa-responsive dystonia and myoclonus-dystonia. Heredodegenerative dystonias are dystonic movements occurring in the context of other heredodegenerative disorders. They may be caused by impaired energy metabolism, impaired systemic metabolism, storage of noxious substances, oligonucleotid repeats and other processes. Pseudodystonias mimic dystonia and include psychogenic dystonia and various orthopedic, ophthalmologic, vestibular, and traumatic conditions. Unusual manifestations, unusual age of onset, suspect family history, suspect medical history, and additional signs may indicate nonprimary dystonia. If they are suspected, etiological clarification becomes necessary. Unfortunately, potential etiologies are legion. Diagnostic algorithms can be helpful. Treatment of nonprimary dystonias, with few exceptions, does not differ from treatment of primary dystonias. The most effective treatment for focal and segmental dystonias is local botulinum toxin injections. Deep brain stimulation of the globus pallidus internus is effective for generalized dystonia. Antidystonic drugs, including anticholinergics, tetrabenazine, clozapine, and gamma-aminobutyric acid receptor agonists, are less effective and often produce adverse effects. Dopamine is extremely effective in dopa-responsive dystonia. The Bertrand procedure can be effective in cervical dystonia. Other peripheral surgery, including myotomy, myectomy, neurotomy, rhizotomy, ramizectomy, and accessory nerve neurolysis, has largely been abandoned. Central surgery other than deep brain stimulation is obsolete. Adjuvant therapies, including orthoses, physiotherapy, ergotherapy, behavioral therapy, social support, and support groups, may be helpful. Analgesics should also be considered where appropriate.

Transcranial sonography in dystonia

The cause of idiopathic dystonia is not entirely elucidated. In the pathophysiological model of dystonia, the basal ganglia play a major role, mainly putamen, globus pallidus internus, thalamus, and cortex. However, using conventional structural neuroimaging methods, no specific alterations could be detected in this area. Using transcranial sonography (TCS) as a noninvasive, easy to perform, and side-effect-free method, it could be shown that in up to 75% of patients with cervical dystonia (CD), in a high percentage of other focal dystonias, but seldom in facial and genetically determined dystonia, hyperechogenicity of the medial part of the lentiform nuclei (LN) can be visualized in the third ventricular scanning plane. Based on these TCS findings an increased copper content of the LN could be verified in dystonia, opening new perspectives on possible pathophysiological aspects and future research. In clinical routine, this method may be used for early and differential diagnosis of primary dystonia.

Deep brain stimulation in dystonia: sonographic monitoring of electrode placement into the globus pallidus internus

Deep brain stimulation (DBS) of the globus pallidus internus (GPi) is an effective treatment in primary dystonia. Its success depends on the implantation accuracy of the DBS electrode into the targeted GPi. Discrepancies of up to 4 mm between the initial target, selected on preoperative MRI, and the final DBS lead location are caused mainly by caudal brain shift that occurs once the cranium is open. Nowadays, transcranial sonography (TCS) can display echogenic deep brain structures with higher image resolution compared to MRI under clinical conditions. Here, we demonstrate for the first time the use of a contemporary clinical high-end TCS system for intraoperative monitoring of DBS electrode position. Herewith, a high-resolution real-time imaging of closely located microelectrodes and of the DBS lead through the intact skull is feasible. Simultaneous color-coded sonographic imaging of arteries near the anatomical target allows further intraoperative refinement of DBS lead positioning, simultaneously preventing hemorrhages.

Transcranial brain sonography findings related to neuropsychological impairment in multiple sclerosis

Cognitive dysfunction, fatigue and mood disorder contribute to the neuropsychological impairment that is common in multiple sclerosis (MS). The present paper reviews application of transcranial brain sonography (TCS) in MS patients and TCS findings related to neuropsychological dysfunction. TCS is a new neuroimaging method displaying tissue echogenicity of the brain through the intact skull. Whereas the cortex can not be discriminated from the subcortical white matter with TCS, subcortical brain structures such as ventricles and basal ganglia can be adequately displayed. Even though TCS proved sensitive and reliable in measuring widths of third and lateral ventricles in a number of neurodegenerative diseases, relatively few TCS studies on MS patients have been reported. Data of these studies suggest a good correlation of cognitive dysfunction and width of third ventricle which can be measured reliably with TCS. Moreover, abnormal TCS findings of basal ganglia were associated with cognitive impairment. However, TCS findings of midbrain structures, basal ganglia and ventricles did not correlate with fatigue or depression in MS patients. TCS has the advantages of low costs, short investigation times and unlimited repeatability. The use of third-ventricle and basalganglia TCS for predicting and monitoring neuropsychological impairment in MS patients, however, needs to be elucidated in further studies.

Transcranial brain parenchyma sonography in movement disorders: state of the art

The present paper summarizes recommendations on transcranial sonography (TCS) application in neurodegenerative diseases, resulting from a consensus meeting of the European Society of Neurosonology and Cerebral Hemodynamics. TCS of distinct infra- and supratentorial brain structures detects characteristic changes in several movement disorders, such as abnormal hyperechogenicity of substantia nigra (SN) in Parkinson's disease and of lenticular nucleus in dystonia, Wilson's disease and atypical Parkinsonian disorders. In healthy adults, the TCS finding of marked SN hyperechogenicity indicates a subclinical functional impairment of the nigrostriatal dopaminergic system. The finding of marked SN hyperechogenicity in combination with normal lenticular-nucleus echogenicity discriminates idiopathic Parkinson's disease from multiple-system atrophy and progressive supranuclear palsy with a positive predictive value of more than 90%. As TCS is a quick and noninvasive method, using the same duplex-ultrasound machines as for investigation of intracranial vessels, applicable even in agitated patients, this method has a great potential to be more widely used.

Disturbance of iron metabolism in Parkinson’s disease — ultrasonography as a biomarker

A central role of iron in the pathogenesis of Parkinson's disease (PD) has been discussed for many years. So far, however, a biomarker indicating increased iron levels in the substantia nigra (SN) in PD patients has been missing. Performing transcranial ultrasound we detected an increased area of SN echogenicity as a typical echofeature in PD, visible already in the early stages of the disease and in subjects with subclinical impairment of the nigrostriatal system. Animal studies and post mortem analyses of human brain tissue revealed that this echofeature is associated with increased iron levels of the substantia nigra as well as a reduced neuromelanin content. The apparently autosomal dominant inheritance of this echofeature in relatives of patients with idiopathic PD indicates a primary role of disturbances of iron metabolism in PD. Consequently performed mutation analyses in genes involved in brain iron metabolism lead to the discovery of specific mutations in the ferritin-H, IRP2 and HFE gene in single PD patients. Moreover, variations in the ceruloplasmin gene were found to be associated with PD or SN hyperechogenicity. Functional relevance of some of these mutations for iron metabolism could be proven. Therefore, SN hyperechogenicity can be regarded as biomarker for both: impairment of the nigrostriatal system and increased iron levels of the SN. Future studies aim at substantiating the hypothesis that healthy subjects with SN hyperechogenicity indeed represent a population at risk for nigrostriatal degeneration, which would have a significant impact on therapeutical options.

New perspectives on dystonia

Dystonia is a syndrome of sustained muscular contractions with numerous underlying etiologies. This review examines the varied phenomenology of dystonias, its evolving classification including recent genetic data as well as its clinical investigation and treatment. Although age of onset, anatomical distribution and family history are key elements of the investigation of dystonia, classification increasingly relies on etiologic and genetic criteria. Physiological abnormalities in striato-cortical circuits are common in dystonia but the pathophysiology is still unclear. In recent years, a great deal has been learned on the more common primary dystonias such as primary torsion dystonia and on dystonia-plus syndromes such as dopamine responsive dystonia. Treatment of dystonia has also evolved and there are now a number of therapeutic agents with clear beneficial effects including anticholinergics, benzodiazepines, and botulinum toxin and there is growing interest in neurofunctional surgery including deep brain stimulation.

Sonographic imaging of the brain parenchyma

Using B-mode transcranial sonography (TCS), it is possible to image the brain parenchyma through the intact skull with conventional low-frequency probes. Several brain disorders can be depicted by TCS such as bleedings, brain tumors, or enlargement of the ventricular system. More recently there is evidence that TCS findings can complement information from other neuroimaging techniques in neurodegenerative disorders leading to new insights and pathophysiological concepts.

Evidence for shoulder girdle dystonia in selected patients with cervical disc prolapse

Some patients with cervical disc herniation suffer from persistent nuchal pain and muscle spasms after decompressive surgery despite the lack of clinical and radiological signs for actual spinal root compression. Sonographic examination of the brain in some of these patients showed increased echogenicity of the lentiform nuclei as described in patients with idiopathic dystonia. This has been linked to an altered Menkes protein level and copper metabolism. We suggest a relationship between persistent nuchal pain after adequate cervical disc surgery and dystonic movement disorders. Thirteen patients with persistent nonradicular nuchal pain after at least one cervical disc surgery and without evidence of continuing spinal root compression and 13 age-matched controls were included. All patients had a complete neurological examination, ultrasound, and MRI scan of the brain. In addition, Menkes protein mRNA levels of leucocytes were analyzed in patients and controls. All patients with persistent nuchal pain exhibited a constant tonic unilateral shoulder elevation associated with an ipsilateral hypertrophy of the trapezius muscle. Ultrasound examination showed an increased echogenicity of the lentiform nucleus in one patient unilaterally and in 10 patients bilaterally but in none of the controls. On MRI the T2-values of the lentiform nuclei were found to be higher in patients exhibiting a hyperechogenicity of the lentiform nuclei compared to controls (P = 0.01). In addition, Menkes protein mRNA levels were decreased in patients with cervical disc herniation (P = 0.03). Clinical, neuroimaging, and biochemical findings of this selected patient sample with chronic nuchal pain and muscle spasms after cervical disc surgery resemble alterations in patients with idiopathic cervical dystonia. This suggests a link between both disorders. A peripheral trauma to the nerve roots may precipitate dystonic movements in susceptible patients and chronic dystonic muscle contraction would account for the persistent nuchal pain.

Cervical dystonia pathophysiology and treatment options

Dystonia is a syndrome of sustained involuntary muscle contractions, frequently causing twisting and repetitive movements or abnormal posturing. Cervical dystonia (CD) is a form of dystonia that involves neck muscles. However, CD is not the only cause of neck rotation. Torticollis may be caused by orthopaedic, musculofibrotic, infectious and other neurological conditions that affect the anatomy of the neck, and structural causes. It is estimated that there are between 60,000 and 90,000 patients with CD in the US. The majority of the patients present with a combination of neck rotation (rotatory torticollis or rotatocollis), flexion (anterocollis), extension (retrocollis), head tilt (laterocollis) or a lateral or sagittal shift. Neck posturing may be either tonic, clonic or tremulous, and may result in permanent and fixed contractures. Sensory tricks ('geste antagonistique') often temporarily ameliorate dystonic movements and postures. Commonly used sensory tricks by patients with CD include touching the chin, back of the head or top of the head. Patients with CD are classified according to aetiology into two groups: primary CD (idiopathic--may be genetic or sporadic) or secondary CD (symptomatic). Patients with primary CD have no evidence by history, physical examination or laboratory studies (except primary dystonia gene) of any secondary cause for the dystonic symptoms. CD is a part of either generalised or focal dystonic syndrome which may have a genetic basis, with an identifiable genetic association. Secondary or symptomatic CD may be caused by central or peripheral trauma, exposure to dopamine receptor antagonists (tardive), neurodegenerative disease, and other conditions associated with abnormal functioning of the basal ganglia. In the majority of patients with CD, the aetiology is not identifiable and the disorder is often classified as primary. Unless the aetiological investigation reveals a specific therapeutic intervention, therapy for CD is symptomatic. It includes supportive therapy and counselling, physical therapy, pharmacotherapy, chemodenervation [botulinum toxin (BTX), phenol, alcohol], and central and peripheral surgical therapy. The most widely used and accepted therapy for CD is local intramuscular injections of BTX-type A. Currently, both BTX type A and type B are commercially available, and type F has undergone testing. Pharmacotherapy, including anticholinergics, dopaminergic depleting and blocking agents, and other muscle relaxants can be used alone or in combination with other therapeutic interventions. Surgery is usually reserved for patients with CD in whom other forms of treatment have failed.

Perspectives of B-mode transcranial ultrasound

Transcranial color coded sonography has proved valuable in the diagnostic work-up of cerebrovascular disorders in adults. More recently, evidences have converged that transcranial sonography is also useful in the diagnosis of brain parenchymal disorders. Here, a new field of application is the visualization of signal intensity shift in specific brain areas in some neurodegenerative disorders (Parkinson's disease, idiopathic dystonia, and depression). Findings obtained by transcranial ultrasound complement information from other neuroimaging data in these disorders and have led to the generation of new pathophysiological concepts. In this review we summarize the application fields of transcranial sonography with special emphasis on recent findings in neurodegenerative disorders and their implications for future research. As new application and processing techniques are being developed transcranial color coded sonography will gain increasing impact on both diagnosis and research of neurological disorders.

Neuroimaging in basal ganglia disorders: perspectives for transcranial ultrasound

Transcranial sonography is a new diagnostic tool, allowing not only the evaluation of cerebral arteries but also the two-dimensional display of the brain parenchyma. In this review we will summarize basics of the application, the ultrasound anatomy of the brain and sonographic findings in some movement disorders. While in normal adults basal ganglia nuclei are hypoechogenic, they are hyperechogenic in certain basal ganglia disorders. In Parkinson's disease, for example, the substantia nigra can be depicted as a distinctly echogenic area. An elevated echogenicity of the lentiform nuclei was noticed in patients with primary adult-onset dystonia. In both disorders the altered echogenicity may arise from higher heavy metal tissue content (i.e. iron in Parkinson's disease and copper in primary dystonia). Our findings converge to the hypothesis that transcranial ultrasound sensitively detects pathological metal accumulation not identified by other neuroimaging techniques (CT and MRI) and therefore provides new insights in the diagnosis of basal ganglia disorders. The implications of these findings for the understanding of the pathogenesis and its usefulness for the early diagnosis of movement disorders are outlined.

Transcranial sonography of the brain parenchyma: comparison of B-mode imaging and tissue harmonic imaging

Transcranial color-coded Duplex sonography (TCCS) has been used for the identification of cerebrovascular disorders. Recently, its value in the diagnosis of disorders of the brain parenchyma has been proposed. The object of this study was to determine systematically the echo pattern of the brain parenchyma and to compare conventional B-mode imaging with tissue harmonic imaging (THI). Transcranial sonography (TCS) was performed in 54 healthy individuals through the temporal bone window using conventional B-mode imaging and THI by two experienced investigators. Identification rates for several brain structures were assessed, and the quality of depiction of each method was graded semiquantitatively. In addition, several parts of the ventricular system and the basal cerebral cisterns were measured. Four subjects did not have an adequate bone window for transcranial examination. In the remaining people, the bone window was assessed to be adequate (59%) or excellent (33%). In the majority (> 80%), TCS allowed an unequivocal identification of various brain structures. Inter-rater variability of the assessments of tissue echogenicity and measurements of the ventricular width were found to be low for several structures (e.g., brainstem, thalamus, or 3rd ventricle). The echo pattern of brain tissue in THI is identical to that described for B-mode imaging. Using THI, contours of brain structures were typically visualized more clearly and the reproducibility of measurements was more consistent. In our experience, insonation of the contralateral lobes was limited when depths were higher than 12 cm using THI. In conclusion, TCS allowed the sonographic examination of the brain parenchyma in the majority of our subjects. THI substantially improves the identification of parenchymal structures when the depth is below 12 cm.