PSP and CBD folks –
SPECT functional imaging is not widely available in the US. I think it is available in only a handful of medical research facilities. This was addressed in a Q&A* in May ’08 during a Parkinson Disease Foundation conference.
Some recently-published French research looks at the results of SPECT scans in 62 people with clinical diagnoses of CBD, PSP, and PD. The researchers were using a special kind of SPECT, called an HmPaO-SPECT, to differentiate between these three disorders. The researchers concluded that this type of SPECT scan can distinguish between these three disorders, quite accurately. “The frontal medial, temporoparietal and parietal regions were the most discriminant.”
The abstract follows. I won’t be getting this full article because it’s in French!
Robin
Revue Neurologique (Paris). 2009 Jan 14. [Epub ahead of print]
[Classification of parkinsonian syndromes via factorial discriminant analysis of brain SPECT data.]
[Article in French]
Kreisler A, Defebvre L, Duhamel A, Lecouffe P, Dujardin K, Steinling M, Pasquier F, Destée A.
Service de neurologie et pathologie du mouvement, hôpital Roger Salengro, Lille, France.
INTRODUCTION: The objective was to assess the value of single photon emission computerized tomography (SPECT) and factorial discriminant analysis (FDA) in the differential diagnosis of Parkinson’s disease (PD), progressive supranuclear palsy (PSP), and corticobasal degeneration (CBD).
PATIENTS AND METHODS: Sixty-two patients with clinical diagnoses of either CBD, PSP or PD were studied using brain HmPaO-SPECT. Thirteen pairs of regions of interest (ROIs) were drawn on the slices located 50mm and 90mm above the canthomeatal plane. Twenty-six uptake indices and 13 asymmetry indices were determined. FDA was performed in order to determine whether or not the patients could be classified into the correct clinical group on the basis of SPECT data alone. The most discriminant parameters were used to generate two predictive scores, which were tested in a second group of 15 patients.
RESULTS: FDA of all 39 variables correctly classified all the patients. A subset of 10 variables was used to build predictive scores, which correctly classified 90% of PD patients, 100% of PSP patients and 86% of CBD patients. When tested in the validation group of 15 patients, these predictive scores correctly classified 87% of the individuals. The frontal medial, temporoparietal and parietal regions were the most discriminant.
CONCLUSION: Using SPECT data alone, this study enabled us to distinguish between PD, PSP and CBD in patients with clear clinical presentations of the diseases in question. This novel, statistical approach provides reliable information. However, a prospective study dealing with de novo parkinsonian syndromes will be necessary.
PubMed ID#: 19150099 (see pubmed.gov)
* Question: Why are SPECT scans not available in the US?
Answer: Because of corporate changes. GE bought Amersham. Amersham wanted to bring another type of SPECT agent to market. It’s been found that the drug that GE started to bring to market in Europe is easier to use. So it got slowed down bringing this agent to the US. GE is talking to the FDA about using European trial data.