Hyperbaric oxygen therapy vs. pharmacological intervention in adults with fibromyalgia related to childhood sexual abuse: prospective, randomized clinical trial.

Fibromyalgia syndrome (FMS) is a chronic pain syndrome characterized by disruptions in pain processing within the central nervous system. It exhibits a high prevalence among patients with a history of traumatic experiences, notably childhood sexual abuse (CSA). This study compared the efficacy of hyperbaric oxygen therapy (HBOT) to the current pharmacological standard of care for individuals suffering from CSA-related FMS. Forty-eight participants diagnosed with FMS and a history of CSA were randomly assigned to either the HBOT group (60 sessions of 100% oxygen at 2 ATA for 90 min, with air breaks every 5 min) or the medication (MED) group (FDA-approved medications, Pregabalin and Duloxetine). The primary endpoint was the Fibromyalgia impact questionnaire (FIQ) score, while secondary endpoints encompassed emotional status and daily functioning questionnaires, as well as pain thresholds and conditioned pain modulation tests. Brain activity was evaluated through single photon emission computed tomography (SPECT). Results revealed a significant group-by-time interaction for the FIQ score favoring HBOT over MED (p < 0.001), with a large effect size (Cohen's d = - 1.27). Similar findings were observed in emotional symptoms and functional measures. SPECT imaging demonstrated an increase in activity in pre-frontal and temporal brain areas, which correlated with symptoms improvement. In conclusion, HBOT exhibited superior benefits over medications in terms of physical, functional, and emotional improvements among FMS patients with a history of CSA. This associated with increased activity in pre-frontal and temporal brain areas, highlighting the neuroplasticity effect of HBOT.

SEEG-RF for revealing and treating Geschwind syndrome's epileptic network: A case study.

Stereotypic neural networks are repeatedly activated in drug-refractory epilepsies (DRE), reinforcing the expression of certain psycho-affective traits. Geschwind syndrome (GS) can serve as a model for such phenomena among patients with temporal lobe DRE. We describe stereo-electroencephalogram (SEEG) exploration in a 34-year-old male with DRE and GS, and his treatment by SEEG-radiofrequency (SEEG-RF) ablation. We hypothesized that this approach could reveal the underlying epileptic network and map eloquent faculties adjacent to SEEG-RF targets, which can be further used to disintegrate the epileptic network. The patient underwent a multi-modal pre-surgical evaluation consisting of video EEG (VEEG), EEG source localization, 18-fluorodexyglucose-PET/MRI, neuropsychological and psychiatric assessments. Pre-surgical multi-modal analyses suggested a T4-centered seizure onset zone. SEEG further localized the SOZ within the right amygdalo-hippocampal region and temporal neocortex, with the right parieto-temporal region as the propagation zone. SEEG-RF ablation under awake conditions and continuous EEG monitoring confirmed the abolishment of epileptic activity. Follow-up at 20 months showed seizure suppression (Engel 1A/ILEA 1) and a significantly improved and stable psycho-affective state. To the best of our knowledge this is the first description of the intracranial biomarkers of GS and its further treatment through SEEG-RF ablation within the scope of DRE.

Anatomic Asymmetry in Sentinel Lymph Node Detection in Endometrial Cancer.

STUDY OBJECTIVE: To determine whether the concomitant use of indocyanine green (ICG) with technetium-99m-filtered sulfur colloid (Tc99m-FSC) improves bilateral sentinel lymph node (SLN) detection rate in endometrial cancer and whether anatomic concordance of pelvic lymph nodes exists and can be used to predict SLN location in cases of unilateral mapping failure. DESIGN: Retrospective cohort study. SETTING: Tertiary academic medical center in Holon, Israel. PATIENTS: Patients diagnosed with endometrial cancer, who underwent SLN mapping with Tc99m-FSC, ICG, or both, at our center between 2014 and 2019. INTERVENTIONS: A total of 111 patients were included in the study. SLN mapping using Tc99m-FSC was performed in 101 (91.9%) patients, and ICG injection was given to 64 (57.6%) patients of whom 55 (49.5%) received both. We compared SLN detection rates (unilateral and bilateral) and anatomic symmetry for each method alone and for a combination of the 2. MEASUREMENTS AND MAIN RESULTS: The overall detection rate for unilateral SLNs was 96.4%; 96.9% with ICG, 93.1% with gamma-probe, and 98.2% by combining both methods. The total bilateral detection rate was 72.1%, with ICG performing better as a single tracer than Tc99m-FSC (75% vs 63.4%, respectively). In 55 women in whom both tracers were used, the bilateral detection rate was significantly higher compared with Tc99m-FSC alone. Symmetric pelvic anatomic concordance of SLN was found in only 35 of 80 patients with bilateral SLN detection (43.8%). CONCLUSION: The combination of preoperative radioisotope injection and intraoperative ICG administration may yield the best bilateral SLN detection rate. In cases of unilateral mapping failure, one cannot rely on the anatomic location of the ipsilateral SLN detected to harvest the complementary node because the symmetric concordance is poor.

The role of exposure to pesticides in the etiology of Parkinson's disease: a 18F-DOPA positron emission tomography study.

Susceptibility to Parkinson's disease (PD) is believed to involve an interaction between genetic and environmental factors. The role of pesticides as a risk factor of PD and neurodegeneration remains controversial. An asymmetric decrease in ligand uptake on 18F-DOPA positron emission tomography (PET), especially in the dorsal putamen, is a sensitive marker of PD. The aim of this study was to examine the pattern of ligand uptake on 18F-DOPA PET in patients with PD exposed or not exposed to pesticides. The main sample included 26 Israeli patients with PD, 13 who were exposed to pesticides and 13 who were not, matched for age and disease duration. All underwent 18F-DOPA PET imaging, and an asymmetry index of ligand uptake between the ipsilateral and contralateral caudate, putamen, and whole striatum was calculated. No significant between-group differences were found in demographic variables, clinical asymmetry index (P = 0.15), or asymmetry index of ligand uptake in the putamen (P = 0.84), caudate (P = 0.78) and striatum (P = 0.45). Comparison of the 18F-DOPA results of the Israeli cohort with those of 17 non-pesticide-exposed patients with PD from Austria yielded no significant differences, further validating our findings. Our observations suggest that although exposure to pesticides might be a risk factor for PD, it does not have an effect on the asymmetry pattern in the nigrostriatal system over non-exposure. We assume that once the disease process is initiated in pesticide-exposed patients, the pathogenic mechanism does not differ from that of idiopathic PD.

Can early dopamine transporter imaging serve as a predictor of Parkinson's disease progression and late motor complications?

BACKGROUND: The role of nuclear imaging in predicting Parkinson's disease (PD) progression is unclear. This study investigated whether the degree of reduced striatal dopamine transporter binding at diagnosis of PD predicts later motor complications and time to disease progression. METHODS: We retrospectively studied 41 patients with early PD who underwent 123I-FP-CIT SPECT and were followed thereafter with a mean disease duration of 9.51 ±â€¯3.18 years. The association of quantitatively analyzed 123I-FP-CIT binding in striatal subregions with the development of motor fluctuations, dyskinesias, freezing of gait (FOG) and falls as well as the time to Hoehn and Yahr (H&Y) stage 3 was evaluated. RESULTS: Logistic regression models controlling for age at diagnosis, sex, disease duration, and L-dopa dose revealed that 123I-FP-CIT binding in the putamen and striatum significantly predicted FOG (OR = 0.02, p = 0.03; OR = 0.01, p = 0.04; respectively) but not falls. Cox proportional hazard analysis did not reveal significant relationship between 123I-FP-CIT binding and motor fluctuations, dyskinesias, or H&Y stage 3. CONCLUSIONS: Our results suggest that a more severe depletion of presynaptic dopamine in early PD is a bad prognostic sign in terms of FOG development. These findings, if replicated, may point to dopaminergic transmission as part of the mechanism underlying FOG in PD.

Perspective: Identification of genetic variants associated with dopaminergic compensatory mechanisms in early Parkinson's disease.

Parkinson's disease (PD) is slowly progressive, and heterogeneity of its severity among individuals may be due to endogenous mechanisms that counterbalance the striatal dopamine loss. In this perspective paper, we introduce a neuroimaging-genetic approach to identify genetic variants, which may contribute to this compensation. First, we briefly review current known potential compensatory mechanisms for premotor and early disease PD, located in the striatum and other brain regions. Then, we claim that a mismatch between mild symptomatic disease, manifested by low motor score on the Unified PD Rating Scale (UPDRS), and extensive Nigro-Striatal (NS) degeneration, manifested by reduced uptake of [(123)I]FP-CIT, is indicative of compensatory processes. If genetic variants are associated with the severity of motor symptoms, while the level of striatal terminals degeneration measured by ligand uptake is taken into account and controlled in the analysis, then these variants may be involved in functional compensatory mechanisms for striatal dopamine deficit. To demonstrate feasibility of this approach, we performed a small "proof of concept" study (candidate gene design) in a sample of 28 Jewish PD patients, and preliminary results are presented.

Association of the ZFPM2 gene with antipsychotic-induced parkinsonism in schizophrenia patients.

RATIONALE: Antipsychotic-induced parkinsonism (AIP) is a severe adverse affect of antipsychotic drug treatment. Recently, our group performed a genome-wide association study (GWAS) for AIP severity, and identified several potential AIP risk variants. OBJECTIVES: The aim of this study was to validate our original AIP-GWAS susceptibility variants and to understand their possible function. METHODS: We conducted a validation study of 15 single-nucleotide polymorphisms (SNPs) in an independent sample of 178 US schizophrenia patients treated for at least a month with typical or atypical antipsychotics. Then, a sample of 49 Jewish Israeli Parkinson's disease (PD) patients with available neuroimaging ([(123)I]-FP-CIT-SPECT) data was analyzed, to study association of confirmed AIP SNPs with level of dopaminergic deficits in the putamen. RESULTS: Using logistic regression and controlling for possible confounders, we found nominal association of the intronic SNP, rs12678719, in the Zinc Finger Protein Multitype 2 (ZFPM2) gene with AIP (62 affected/116 unaffected), in the whole sample (p = 0.009; P = 5.97 × 10(-5) in the GWAS), and in the African American sub-sample (N = 111; p = 0.002). The same rs12678719-G AIP susceptibility allele was associated with lower levels of dopaminergic neuron related ligand binding in the contralateral putamen of PD patients (p = 0.026). CONCLUSIONS: Our preliminary findings support association of the ZFPM2 SNP, rs12678719, with AIP. At the functional level, this variant is associated with deficits in the nigrostriatal pathway in PD patients that may be related to latent subclinical deficits among AIP-prone individuals with schizophrenia. Further validation studies in additional populations are required.

Residual striatal dopaminergic nerve terminals in very long-standing Parkinson's disease: a single photon emission computed tomography imaging study.

Molecular imaging studies of Parkinson's disease (PD) progression mostly focus on the first 5 years after disease onset, demonstrating rapid initial nigrostriatal neuronal loss. The fate of residual functional dopaminergic nerve terminals in patients with long-standing PD has not yet been specifically explored. Therefore, we performed [(123)I]-FP-CIT single photon emission computed tomography (SPECT) in 15 patients with very long-standing PD (mean disease duration 20.6 ± 6.3 years). Measurable uptake of [(123)I]-FP-CIT was still detected in the striata of all patients. As seen in early stages, reduction of tracer uptake in the putamen was more prominent than in the caudate nucleus. Asymmetry in tracer uptake between the two putamen and caudate nuclei was preserved. These findings indicate that degeneration of dopaminergic neurons in PD is not total even after many years of illness. Data should be considered in exploring underlying causes of progressive loss of nigrostriatal dopaminergic neurons and development of future novel dopaminergic therapeutic strategies in PD.

Early outcome of acute ischemic stroke in hyperlipidemic patients under atorvastatin versus simvastatin.

BACKGROUND: Studies designed to evaluate the efficacy of atorvastatin on stroke suggest that, in addition to cholesterol lowering, this drug may play a role in poststroke neuroprotection. The objective of this historical-prospective study was to analyze the efficacy of atorvastatin (40-80 mg) or simvastatin (at an optimal dose) during the first 2 weeks after stroke in hyperlipidemic patients treated with simvastatin before stroke onset. METHODS: Medical records of all adult (aged >18 years) patients diagnosed with acute stroke were reviewed. Subjects were categorized on the basis of poststroke treatment exposure: atorvastatin (40 or 80 mg) or simvastatin (at an optimal dose). Each patient was examined using the National Institutes of Health Stroke Scale (NIHSS) and the modified Rankin Scale (mRS). Blood lipid profile was determined. All tests were performed at baseline and at 4 weeks after stroke. RESULTS: A total of 371 patients (249 male and 122 female) were included. Subjects who received simvastatin were significantly older than those who received either dose of atorvastatin. Baseline differences in functional scores were not detected across treatment groups. Two weeks after stroke, subjects exposed to simvastatin had significantly poorer NIHSS and mRS scores than did subjects exposed to either atorvastatin dose. Atorvastatin 80 mg was associated with significantly better outcome compared with either of the other treatment groups. These differences persisted even after controlling for age and baseline scores. CONCLUSIONS: Early outcome measured by NIHSS and mRS was better in acute stroke patients treated with atorvastatin than in those treated with simvastatin. These differences may reflect a neuroprotective effect unique to atorvastatin.

Use of a single [123I]-FP-CIT SPECT to predict the severity of clinical symptoms of Parkinson disease.

The aim of this study was to assess the ability of a single SPECT performed in the early stage of Parkinson's disease (PD) to predict disease severity in 19 patients with early PD. [(123)I]-FP-CIT striatal uptake was expressed as a ratio of specific:nonspecific uptake for defined brain areas. Clinical severity was determined by the UPDRS at baseline and 12-15 months following the SPECT procedure. [(123)I]-FP-CIT uptake in the contralateral putamen and striatum was correlated with UPDRS score at baseline, with a more significant correlation after 1-year interval. [(123)I]-FP-CIT uptake in all areas was correlated with bradykinesia and rigidity subscores only at follow up visit. Significant correlations were found between [(123)I]-FP-CIT uptake in the contralateral striatum, putamen and caudate and the difference between motor scores of 1-year interval (DeltaUPDRS). These results suggest that disease severity might be anticipated by a single SPECT at an early stage of the disease.

The use of 99mTc-recombinant human annexin V imaging for differential diagnosis of aseptic loosening and low-grade infection in hip and knee prostheses.

UNLABELLED: The aim of this study was to assess the pattern of annexin V uptake in hip and knee prostheses suspected of being infected. METHODS: A total of 7 patients undergoing revision surgery for hip or knee prostheses were studied; 5 patients had total hip replacements, and 2 had total knee replacements. Infection was confirmed by pathology, culture results, laboratory evaluation, and clinical follow-up. All patients also underwent a bone scan before surgery. RESULTS: Annexin V scan findings were positive in 5 patients and negative in 2. Annexin V uptake was either focal (n = 4) or linear (n = 1). There were 4 true-positive, 2 true-negative, 1 false-positive, and no false-negative annexin V studies. Annexin V uptake was either more extensive or less extensive than, and usually was incongruent with, (99m)Tc-methylene diphosphonate uptake. CONCLUSION: Our findings suggest that annexin V imaging shows greater uptake with infection than with aseptic loosening and has a high negative predictive value for prosthetic infection.

I-123 MIBG cardiac scintigraphy and autonomic test evaluation in multiple sclerosis patients.

Autonomic symptoms are common in multiple sclerosis (MS) patients and may cause significant disability. The purpose of this study was to evaluate direct cardiac sympathetic denervation in MS patients with I-123 MIBG cardiac scintigraphy compared with other parasympathetic electrophysiological examinations of autonomic dysfunction. Ten patients with MS and 7 age- and sex-matched control subjects were prospectively evaluated. The neurological deficit and disability stages of the patients were rated according to the Kurtzke Expanded Disability Status Scale (EDSS). Autonomic tests included the R-R interval, Valsalva ratio and standup test. All patients and control subjects had planar and SPECT cardiac scintigraphy with I-123 MIBG injection. Seven MS patients had relapsing-remitting (R-R) type and three had secondary progressive type (SP). A pathological MIBG cardiac washout rate was found in 3/10 MS patients, all of them with SP-MS. The other seven had normal washout rates. No correlation was found between the scan and the individual parasympathetic autonomic test results. I-123 MIBG myocardial scintigraphy may detect direct disturbances of the sympathetic cardiac function in patients with MS in addition to parasympathetic dysfunction tests and can be an important additional means of assessing autonomic pathways. Determination in MS of the co-existence of autonomic dysfunction, especially the cardiac sympathetic involvement in the SP type, may aid in evaluation of disease severity and cardiac function follow-up.

123I-FP-CIT SPECT imaging of dopamine transporters in patients with recurrent sudden falls: are such falls a distinct entity?

UNLABELLED: Recurrent falls in older people are commonly associated with abnormalities that involve several parts of the central nervous system, especially with basal ganglion pathology. The aim of the present study was to evaluate the integrity of striatal dopamine transporters (DaTs) by use of (123)I-N-3-fluoropropyl-2beta-carbomethoxy-3beta-(4-iodophenyl)tropane ((123)I-FP-CIT) SPECT of striatal DaTs in patients with recurrent sudden falls. METHODS: Twenty-one patients without a definite neurologic diagnosis for recurrent sudden falls were enrolled in a cross-sectional study. SPECT with a DaT ligand was performed 180 min after injection of 185 MBq of (123)I-FP-CIT with a dual-head gamma-camera. RESULTS: DaT SPECT findings were normal in 15 of 21 patients (71%). Of those, 73% had abnormal MRI findings suggestive of atherosclerotic lesions. Eleven patients with normal DaT SPECT findings had mild parkinsonian symptoms. There was no correlation of the SPECT results with patient age, duration of occurrence of falls, or frequency of falls, and there was no significant difference in the relative distributions of SPECT findings between patients with and patients without parkinsonian symptoms or vascular risk factors. CONCLUSION: Recurrent sudden falls are, in most cases, not attributable to the degeneration of the nigrostriatal system.

Drug-induced thyrotoxicosis: the surgical option.

BACKGROUND: Drug-induced thyrotoxicosis is not uncommon. It may worsen life-threatening arrhythmias and may be refractory to medical treatment. Near-total thyroidectomy presents a valid alternative to medical therapy and should be considered early in the management of the disease. OBJECTIVES: To assess whether near-total thyroidectomy was a viable approach for our patients. METHODS: Twelve patients--7 men and 5 women, aged 63 to 82 years--presented with drug-induced fulminant thyrotoxicosis following 1 to 12 months of amiodarone treatment (11 patients, mean 7 months) and after a 6 months course of interferon-alpha treatment (one patient). Medical therapy included propylthiouracil in doses up to 1200 mg/day in all patients and a beta-receptor antagonist in seven. Five patients had to stop amiodarone treatment and start high doses of steroids. A thyroid scan was performed in all patients using 5 mCi of Tc-99m pertechnetate. The thyroid scan showed absent uptake of the tracer in the thyroid bed in all patients, precluding the use of radioablation. RESULTS: Four patients (three with AIT and one with interferon therapy) who did not respond to 3 months of medical therapy required surgical thyroidectomy due to severe unremitting thyrotoxicosis. A near-total thyroidectomy resulted in rapid correction of thyrotoxicosis, enabling continuation of the anti-arrhythmic drug. There were no intraoperative or postoperative arrhythmias. Subsequently, all patients recovered rapidly and remained well and euthyroid on thyroxine replacement therapy. CONCLUSIONS: Since surgery results in rapid control of thyrotoxicosis and permits continued therapy with amiodarone, we suggest that near-total thyroidectomy warrants consideration as a definitive treatment for resistant amiodarone or interferon-induced thyrotoxicosis.

Prospective evaluation of malignant middle cerebral artery infarction with blood-brain barrier imaging using Tc-99m DTPA SPECT.

BACKGROUND: Malignant middle cerebral artery (MMCA) infarction is associated with severe brain edema which may lead to a rapid deterioration of consciousness, increase of intracranial pressure, brain midline shift and finally, herniation. We examined the correlation between the degree of the blood-brain barrier (BBB) permeability and MMCA. METHODS: Twenty-five consecutive patients (17 men and 8 women, mean age 62.1+/-10.1) were included in the study. Each patient had a daily clinical examination, and the neurological deficits were scored using NIHSS score. A CT without contrast material was performed in all patients. (99m)Tc-DTPA SPECT was performed at 36 h after the stroke. A quantitative index of BBB breakdown (disruption index) was calculated. RESULTS: The mean volume of stroke was 138+/-87 cm(3). The mean DTPA disruption index was 6.6+/-4.6 (range 1.0-21.0). The mean NIHSS score was 14+/-4 (p=0.2). Five of 25 patients had brain herniation as evidenced on brain CT. The volume of stroke was only marginally elevated in patients with herniation (p=0.062). All patients showed significant, inverse correlation between NIHSS score and DTPA uptake (r=-0.43, p=0.033). There was a significant correlation between the extent of DTPA distribution (more than one vascular territory) and the occurrence of herniation (p<0.001). CONCLUSIONS: DTPA-SPECT imaging is a reliable complementary predictive tool in patients with an MCA stroke. The specific pattern found on DTPA SPECT, compatible with diffuse BBB disruption, may be of value in predicting "malignant MCA."

In vivo imaging of apoptosis in patients with acute stroke: correlation with blood-brain barrier permeability.

BACKGROUND: We wished to determine the ability of radiolabeled annexin V to concentrate at sites of ischemic injury in patients with acute cerebral stroke. Secondly, we sought to correlate annexin V imaging in these patients with the degree of blood-brain barrier (BBB) breakdown. METHODS: Twelve patients with acute stroke had a complete neurological examination, including the National Institutes of Health (NIH) stroke scale and the Glasgow Coma Score (GCS). A non-contrast CT scan was performed on all patients. A SPECT of the brain was obtained 2 h after injection of annexin V. The integrity of the BBB was evaluated in seven patients using Tc-99m-DTPA brain SPECT. RESULTS: All patients had an infarct in the MCA territory. Eight patients had abnormal increased annexin V activity, which was more common in patients with cortical strokes (P = 0.01). The concentration of annexin had no correlation to the volume of stroke, but it was significantly and inversely related to the GCS on admission (r = -0.7, P = 0.02). Foci of apoptosis were noted contralateral to the affected hemisphere as well. All seven patients who underwent DTPA SPECT showed breakdown of the BBB. DTPA uptake was significantly and positively associated with NIH score (r = 0.80, P = 0.01) and inversely associated with GCS (r = -0.89, P = -0.03). CONCLUSION: This study shows that it is possible to identify in vivo regions of ischemic neuronal injury using radiolabeled annexin V in patients with acute stroke. Annexin imaging can play a major role in the selection of therapy in the initial period following stroke in adults.

Fat intolerance in developmentally impaired children with severe feeding intolerance.

Children with a variety of genetic, metabolic, and neurologic disorders can suffer from severe feeding intolerance that is unresponsive to medical, surgical, and nutritional therapy. Developmentally disabled tube-fed children with severe upper gastrointestinal symptoms that persisted after fundoplication who were unresponsive to all medical, surgical, and nutritional interventions underwent a thorough gastrointestinal evaluation, including gastroscopy, pH-metry, upper gastrointestinal barium series, and gastric emptying studies. They were placed on a low-fat diet, and the symptoms before and after the diet were compared. The patients were then rechallenged with incremental increases in fat until the symptoms recurred or the patients reached their former fat concentration. Six children meeting the study criteria were evaluated. Four of these patients had a significant improvement in symptoms, oral intake and feeding tolerance with a decrease in fat intake, and relapse of symptoms when fat calories were increased. Improvement occurred in children who had been intolerant to duodenal feeding. We were subsequently able to wean two children from tube feeding. Dietary fat can provoke upper gastrointestinal symptoms in children with gastric and intestinal dysmotility. Short-term manipulation of dietary fat intake can improve tolerance to feeding.

[123I]-FP/CIT SPECT imaging for distinguishing drug-induced parkinsonism from Parkinson's disease.

Parkinsonism in patients taking neuroleptic medications might be induced by dopamine receptor blockade alone or by dopamine blockade with nigrostriatal dysfunction. The differentiation between Parkinson's disease (PD) and drug-induced parkinsonism (DIP) is difficult to assess on clinical grounds alone. In this study, we have evaluated the clinical characteristics and striatal binding of (123)I-FP-CIT (N-omega-fluoropropyl-2beta-carboxymethoxy-3beta-{4-iodophenyl}tropane) in patients who developed DIP. A total of 20 patients (mean age, 62 +/- 13 years) who developed parkinsonism while on neuroleptic agents and 10 age-matched controls were enrolled. [123]-FP-CIT single-photon emission computed tomography (SPECT) was performed in all subjects. Neurological assessment was performed with the Motor part of the Unified Parkinson's Disease Rating Scale. [123]-FP-CIT binding of the entire striatum, caudate, and putamen was calculated. Patients were divided into two subgroups according to SPECT results for comparison of clinical characteristics. There were 9 patients who had normal scans and 11 who showed significantly diminished striatal binding, suggesting degeneration of the nigrostriatal system. Subanalyses of abnormal scans revealed significantly diminished binding in the caudate (P < 0.001 for right and left caudate) and putamen (P = 0.002 and P < 0.05 for right and left putamen, respectively). There were no differences in clinical features between patients with normal and abnormal scans. Symptoms included asymmetric tremor, bradykinesia, and rigidity in both groups. Freezing gait was present in two patients with normal scans. These results indicate that DIP is clinically indistinguishable from PD. Brain imaging with FP-CIT helps to determine whether DIP is entirely drug-induced or an exacerbation of subclinical PD.