Parkinson's disease (PD) patients often show marked improvement of hypokinetic gait when exposed to special stimuli. To investigate physiological mechanisms underlying this "paradoxical gait" induced by visual cues in PD patients, we examined regional cerebral blood flow changes during gait on a treadmill guided by two different visual cues, the lines oriented transversely to the direction of w...

BACKGROUND AND PURPOSE Meta-analysis of previous trials of oral nimodipine in acute stroke has suggested a benefit when commenced within 12 hours of onset. We sought to study the effect of oral nimodipine on reperfusion after acute stroke and the relation between reperfusion and outcome. METHODS Fifty patients with acute middle cerebral artery territory cortical infarction were blindly random...

BACKGROUND AND PURPOSE Concerning vasoreactivity of cerebellar blood flow (CeBF) in patients affected with crossed cerebellar diaschisis (CCD), several controversies have been reported. One is reduced asymmetry of CeBF after acetazolamide administration in 99mTc hexamethylpropyleneamine oxime single-photon emission-computed tomography, and the other is persistent asymmetry with alternation in P...

UNLABELLED Compromised regional cerebral blood flow (rCBF) in major depressive disorder may be partly reversed by successful antidepressant treatment. However, it is not known if the reversal of rCBF compromise is dependent on the mode of antidepressant treatment. The current study aimed to address this question. METHODS Thirty-three patients (19 women and 14 men; mean age +/- SD, 53 +/- 16 y...

1515 OBSTRUCTIVE SLEEP APNEA-HYPOPNEA SYNDROME (OSAHS) IS CHARACTERIZED BY REPEATED EPISODES OF UPPER AIRWAY OBSTRUCTION DURING SLEEP, with disturbances in arterial blood gases and increasing inspiratory effort until the upper airway obstruction discontinues due to arousal. OSAHS has a relatively high prevalence and occurs in 5% of the adult population.1 OSAHS may cause daytime sleepiness, redu...

OBJECTIVES To study the ability of technetium-99m hexamethyl propylene amineoxime (HMPAO) labelled lymphocyte scintigraphy to quantify synovial inflammation, and to analyse the kinetics of lymphocyte retention in the joints of patients with rheumatoid arthritis (RA). METHODS After isolation of the lymphocytes, the cells were radiolabelled in vitro with 250 MBq 99mTc-HMPAO. The scans were perf...

Here, we present the case of an extremely subtle peripheral graft infection caused by Staphylococcus aureus. The lack of local signs and the negativity of all imaging studies, including (99m)Tc-HMPAO-Labelled-Leukocyte Scan which is reported to have 100% sensitivity, delayed the diagnosis and therapy, which were both provided by surgery.

We have generalized the spectral factor analysis and the factor analysis of dynamic sequences (FADS) in SPECT imaging to a five-dimensional general factor analysis model (5D-GFA), where the five dimensions are the three spatial dimensions, photon energy, and time. The generalized model yields a significant advantage in terms of the ratio of the number of equations to that of unknowns in the fac...

BACKGROUND AND PURPOSE To increase the reliability of 99mTc-hexamethyl propyleneamine oxime (HMPAO) single photon emission computed tomography (SPECT) study in the evaluation of hemodynamic change with balloon test occlusion (BTO) of the internal carotid artery, we attempted to clarify the usefulness of additional monitoring of regional oxygen saturation of the brain (rSO2). METHODS During BT...

The effects of caloric vestibular stimulation on regional cerebral blood flow (rCBF) of the parietal and temporal cortex were examined in 10 healthy volunteers. The consecutive 99mTe-hexamethyl-propyleneamine oxime (99mTc-HMPAO) single-photon emission computed tomography (SPECT) method with region of interest analysis was used. Changes in rCBF induced by caloric stimulation with cold air (25 de...