New developments in diagnosis and treatment of Parkinson's disease--from basic science to clinical applications

Adverse events in total knee arthroplasty: Results of a physician independent survey in 260 patients

Purpose

Identification of all common and potentially avoidable adverse events is crucial to further improve the quality of medical care. The intention of the current study was to evaluate a standardized physician independent survey format on adverse events in total knee arthroplasty. The protocol for reporting adverse drug events following the International Conference of Harmonisation of technical requirements for registration of pharmaceuticals for human use (ICH) was adopted for adverse events occurring during surgical interventions.

Material and methods

Data of a prospective sequential cohort trial introducing a clinical pathway for total knee arthroplasty was analysed. Reporting of adverse events was done by a physician independent study nurse using the modified ICH-Good Clinical Practice (GCP) format (Structure and Content of Clinical study reports - E3) in 260 patients. The adverse events were graded to their severity and their potential relation to surgical treatment.

Results

A total of 55 patients (21%) suffered from an adverse event and 16 (6%) from a serious adverse event. In 38 patients' one adverse event occurred, 12 patients showed 2 adverse events and 5 patients suffered from a combination of an adverse and a serious adverse event. A serious adverse event alone occurred in 11 patients. The incidence of adverse events (Fisher p = 0.448) and serious adverse (p = 0.126) events showed no significant difference between the two cohorts. The most common adverse events were deep vein thrombosis (8% and 5%) followed by wound healing problems (1% and 0%) and haematoma (1% and 3%). A wide range of non surgical adverse events were recorded with low incidence levels.

Conclusion

The use of the modified ICH-GCP format supports standardization of adverse event reporting. Routine assessment of adverse events by a study nurse revealed higher incidence rates of adverse events in total knee arthroplasty. We recommend the implementation of trained paramedical staff for the documentation of adverse events in routine clinical care.

Transcranial duplex in the differential diagnosis of parkinsonian syndromes: a systematic review

BACKGROUND

Transcranial duplex scanning (TCD) of the substantia nigra (SN) is increasingly used to diagnose Idiopathic Parkinson's Disease (IPD). Up until now 70 diagnostic studies have been published, not only on investigation of the SN, but also of the lenticular nucleus (LN) and the Raphe nuclei (RN).

METHOD

We systematically reviewed all diagnostic TCD studies in parkinsonian patients up to June 2008.

RESULTS

We found 35 eligible studies. Of the 1534 IPD patients investigated in the 35 studies 200 (13%) had an inconclusive SN-TCD. An increased echo-intensity of the SN was seen in 1167 (87%) of the 1334 IPD patients, 276 (12%) of the 2340 healthy controls and in 41 (30%) of the 138 patients with an atypical parkinsonian syndrome (APS). On the contrary, a pathological LNTCD was found more often in APS patients (79%) than in IPD patients (23%) and healthy controls (6%). A decreased echo-intensity of the RN was found more often in depressed (46%) than in non-depressed IPD patients (16%).

CONCLUSIONS

SN-TCD accurately differentiates between patients with IPD and healthy controls, but not between patients with IPD and APS. LN-TCD is only moderate accurate to delineate IPD from APS, but combinations of SN- and LN-TCD may be more promising. RN-TCD has only marginal diagnostic accuracy in diagnosing depression in IPD and non-IPD patients. Before TCD can be implicated, more research is needed to standardize the TCD technique, to investigate the TCD in non-research settings and to determine the additional value of TCD compared with currently used clinical techniques like SPECT imaging.

Tetrahydroisoquinoline derivatives: a new perspective on monoaminergic dysfunction in children with ADHD?

BACKGROUND

The dopamine-derived tetrahydroisoquinolines (TIQ) synthesized endogeneously from aldehydes and catecholamines have shown to modulate neurotransmission, central metabolism and motor activity. Converging evidence has implicated abnormalities of the dopamine metabolism to the pathophysiology of Attention-Deficit/Hyperactivity Disorder (ADHD). Therefore, four TIQ derivatives involved in central dopamine metabolism (salsolinol, N-methyl-salsolinol, norsalsolinol, N-methyl-norsalsolinol) have been analyzed for the first time in children and adolescents with ADHD and healthy controls.

METHODS

42 children and adolescents with ADHD and 24 controls from three sites participated in this pilot study. Free and bound amounts of salsolinol, N-methyl-salsolinol, norsalsolinol, N-methyl-norsalsolinol have been analyzed in urine.

RESULTS

In the ADHD group, free and total amounts of the four TIQ derivatives in urine were significantly higher compared to urine levels of healthy controls. For N-methyl-salsolinolfree, most of the ADHD patients were identified correctly with a sensitivity of 92.5% (specificity 94.4%).

CONCLUSION

Urine levels of salsolinol, N-methyl-salsolinol, norsalsolinol and N-methyl-norsalsolinol are elevated in children and adolescents with ADHD and point to a new perspective on catecholaminergic dysfunction in ADHD. However, replication and extension of this pilot study would progress this innovative and promising field.

Protocol of a prospective study on the diagnostic value of transcranial duplex scanning of the substantia nigra in patients with parkinsonian symptoms

BACKGROUND

Parkinson's disease (PD) is the second most common neurodegenerative disorder. As there is no definitive diagnostic test, its diagnosis is based on clinical criteria. Recently transcranial duplex scanning (TCD) of the substantia nigra in the brainstem has been proposed as an instrument to diagnose PD. We and others have found that TCD scanning of substantia nigra duplex is a relatively accurate diagnostic instrument in patients with parkinsonian symptoms. However, all studies on TCD so far have involved well-defined, later-stage PD patients, which will obviously lead to an overestimate of the diagnostic accuracy of TCD. We have therefore set out to conduct a prospective study testing the diagnostic accuracy of TCD in patients with a parkinsonism of unclear origin.

METHODS/DESIGN

We will enroll 250 consecutive patients, who are referred to neurology outpatient clinics of two teaching hospitals, for analysis of clinically unclear parkinsonism. Patients, whose parkinsonism is clearly diagnosable at the first visit, will be excluded from the study. All patients will undergo a TCD of the substantia nigra. As a surrogate gold standard we will use the consensus clinical diagnosis reached by two independent, blinded, movement disorder specialist neurologists after 2 years follow-up. At the time of TCD, patients will also undergo a SPECT scan of the brain.

DISCUSSION

As this prospective trial enroll only patients with an early-stage parkinsonism, it will yield data on the diagnostic accuracy of TCD that is relevant to daily clinical practice: The neurologist needs a diagnostic tool that provides additional information in patients with a clinically indefinable parkinsonian syndrome. The above described observational longitudinal study was designed to explicitly study this aspect in the diagnostic process.

Meta-analysis of the literature on diagnostic accuracy of SPECT in parkinsonian syndromes

BACKGROUND

Parkinson's disease (PD) is the second most common neurodegenerative disorder. One of the most widely used techniques to diagnose PD is a Single Photon Emission Computer Tomography (SPECT) scan to visualise the integrity of the dopaminergic pathways in the brain. Despite this there remains some discussion on the value of SPECT in the differential diagnosis of PD. We did a meta-analysis of all the existing literature on the diagnostic accuracy of both pre- and post-synaptic SPECT imaging in the differential diagnosis of PD.

METHODS

Relevant studies were searched in Medline, EMBASE and Cochrane databases with back-searching of their reference lists. We limited our analysis to studies with a clinically relevant methodology: i.e. when they assessed the ability of the SPECT to provide 1. diagnosis of PD in an early phase vs. normalcy; 2 diagnostic differentiation between PD and essential tremor (ET); 3. distinguishing between PD and vascular parkinsonism (VP); 4. delineation of PD from atypical parkinsonian syndromes (APS). Gold standard was, dependent on the study type, clinical examination at initial visit or follow-up, and/or response to dopaminergic agents.

RESULTS

The search gave 185 hits, of which we deemed 32 suitable for our analysis. From these we recalculated the diagnostic odds ratio of SPECT for the clinical questions above. The pooled odds ratio (with 95%CI) for presynaptic SPECT scan's ability to distinguish between early PD and normalcy was 60 (13 - 277). For the ability to differentiate between PD and ET this ratio was 210 (79-562). The ratio for presynaptic SPECT's ability to delineate PD from VP was 105 (32 - 348). The mean odds ratio for the presynaptic SPECT scans to differentiate between PD and the two APS was 2 (1 - 4), and for the postsynaptic SPECT imaging this was 19 (9-36).

CONCLUSION

SPECT with presynaptic radiotracers is relatively accurate to differentiate patients with PD in an early phase from normalcy, patients with PD from those with ET, and PD from VP. The accuracy of SPECT with both presynaptic and postsynaptic tracers to differentiate between PD and APS is relatively low.