Owing to its highly biocompatible property as naturally produced nanoscale particle and drug carrying ability, exosome has attracted much interest in the biomedical area. Versatile functions of exosome in biological system play an important role in elucidating mysterious and unknown biological processes and pathological disease progression. For usage of exosome as brain disease therapeutics, even though the ability of exosomes crossing blood brain barrier (BBB) is not well clearly proven, the small size and their own characteristics possessing cell-derived molecular contents may provide great and beneficial tools for brain delivery and brain-associated disease therapy. A variety of trials related to bioapplications using stem cell-derived exosome in regenerative therapy or autologous exosome shuttling inhibitor targeting brain disease-associated protein marker enhance possibility of exosome toward clinical application. The radionuclide PETor SPECT imaging of radiolabeled exosome will be clearly able to provide accurate clues for analyzing their whole body distribution, targeting efficacy, and the degree of non-specific tissue uptake. In this perspective, the practical information on thranostics of exosome for brain delivery and therapy is offered and radionuclide-based exosome applicability will be dealt with.
Biological Processes ; Blood-Brain Barrier ; Brain Diseases ; Brain ; Disease Progression ; Exosomes ; Lifting ; Radionuclide Imaging ; Theranostic Nanomedicine ; Tomography, Emission-Computed, Single-Photon

The first step to nuclear medicine in Korea started with introduction of the gamma camera in 1969. Although planar images with the gamma camera give important functional information, they have the limitations that result from 2-dimensional images. Single-photon emission computed tomography (SPECT) due to its 3-dimensional image acquisition is superior to earlier planar gamma imaging in image resolution and diagnostic accuracy. As demand for a hybrid functional and anatomical imaging device has increased, integrated SPECT/CT systems have been used. In Korea, SPECT/CT was for the first time installed in 2003. SPECT/CT can eliminate many possible pitfalls on SPECT-alone images, making better attenuation correction and thereby improving image quality. Therefore, SPECT/CT is clinically preferred in many hospitals in various aspects.More recently, additional SPECT/CT images taken from the region with equivocal uptake on planar images have been helpful in making precise interpretation as part of their clinical workup in postoperative thyroid cancer patients. SPECT and SPECT/CT have various advantages, but its clinical application has gradually decreased in recent few years. While some researchers investigated the myocardial blood flow with cardiac PET using F-18 FDG or N-13 ammonia, myocardial perfusion SPECT is, at present, the radionuclide imaging study of choice for the risk stratification and guiding therapy in the coronary artery disease patients in Korea. New diagnostic radiopharmaceuticals for AD have received increasing attention; nevertheless, brain SPECT will remain the most reliable modality evaluating cerebral perfusion.
Ammonia ; Brain ; Coronary Artery Disease ; Gamma Cameras ; Humans ; Korea ; Nuclear Medicine ; Perfusion ; Radionuclide Imaging ; Radiopharmaceuticals ; Thyroid Neoplasms ; Tomography, Emission-Computed ; Tomography, Emission-Computed, Single-Photon

PURPOSE: We evaluated hemodynamic significance of stenosis on magnetic resonance angiography (MRA) using acetazolamide perfusion single photon emission computed tomography (SPECT). MATERIALS AND METHODS: Of 171 patients, stenosis in internal carotid artery (ICA) and middle cerebral artery (MCA) (ICA-MCA) on MRA and cerebrovascular reserve (CVR) of MCA territory on SPECT was measured using quantification and a 3-grade system. Stenosis and CVR grades were compared with each other, and their prognostic value for subsequent stroke was evaluated. RESULTS: Of 342 ICA-MCA, 151 (44%) presented stenosis on MRA; grade 1 in 69 (20%) and grade 2 in 82 (24%) cases. Decreased CVR was observed in 9% of grade 0 stenosis, 25% of grade 1, and 35% of grade 2. The average CVR of grade 0 was significantly different from grade 1 (p<0.001) and grade 2 stenosis (p=0.007). In quantitative analysis, average CVR index was -0.56+/-7.91 in grade 0, -1.81+/-6.66 in grade 1 and -1.18+/-5.88 in grade 2 stenosis. Agreement between stenosis and CVR grades was fair in patients with lateralizing and non-lateralizing symptoms (kappa=0.230 and 0.346). Of the factors tested, both MRA and CVR were not significant prognostic factors (p=0.104 and 0.988, respectively), whereas hypertension and renal disease were significant factors (p<0.05, respectively). CONCLUSION: A considerable proportion of ICA-MCA stenosis detected on MRA does not cause CVR impairment despite a fair correlation between them. Thus, hemodynamic state needs to be assessed for evaluating significance of stenosis, particularly in asymptomatic patients.
*Acetazolamide ; Adult ; Aged ; Aged, 80 and over ; Brain/blood supply/radionuclide imaging ; Carotid Artery, Internal/physiopathology/radionuclide imaging ; Carotid Stenosis/physiopathology/*radionuclide imaging ; *Cerebrovascular Circulation ; Constriction, Pathologic ; Diuretics ; Female ; *Hemodynamics ; Humans ; Hypertension/physiopathology ; Iodine Radioisotopes ; *Magnetic Resonance Angiography ; Male ; Middle Aged ; *Radiopharmaceuticals ; Tomography, Emission-Computed, Single-Photon/*methods

PURPOSE: As Parkinson's disease (PD) can be considered a network abnormality, the effects of deep brain stimulation (DBS) need to be investigated in the aspect of networks. This study aimed to examine how DBS of the bilateral subthalamic nucleus (STN) affects the motor networks of patients with idiopathic PD during motor performance and to show the feasibility of the network analysis using cross-sectional positron emission tomography (PET) images in DBS studies. MATERIALS AND METHODS: We obtained [15O]H2O PET images from ten patients with PD during a sequential finger-to-thumb opposition task and during the resting state, with DBS-On and DBS-Off at STN. To identify the alteration of motor networks in PD and their changes due to STN-DBS, we applied independent component analysis (ICA) to all the cross-sectional PET images. We analysed the strength of each component according to DBS effects, task effects and interaction effects. RESULTS: ICA blindly decomposed components of functionally associated distributed clusters, which were comparable to the results of univariate statistical parametric mapping. ICA further revealed that STN-DBS modifies usage-strengths of components corresponding to the basal ganglia-thalamo-cortical circuits in PD patients by increasing the hypoactive basal ganglia and by suppressing the hyperactive cortical motor areas, ventrolateral thalamus and cerebellum. CONCLUSION: Our results suggest that STN-DBS may affect not only the abnormal local activity, but also alter brain networks in patients with PD. This study also demonstrated the usefulness of ICA for cross-sectional PET data to reveal network modifications due to DBS, which was not observable using the subtraction method.
Aged ; Brain/*radionuclide imaging ; Cross-Sectional Studies ; Deep Brain Stimulation/*methods ; Female ; Functional Laterality/*physiology ; Humans ; Male ; Middle Aged ; Parkinson Disease/radionuclide imaging/*therapy ; Positron-Emission Tomography ; Severity of Illness Index ; Subthalamic Nucleus/*physiopathology

Hypernatremia is a rare cause of rhabdomyolysis. Here, we report a case of hypernatremia-induced rhabdomyolysis in a patient with meningioma involving the pituitary gland. A 61-year-old male was admitted for decreased mentality and poor oral intake. He had undergone an operation for meningioma 10 years prior. At admission, he appeared lethargic and severely dehydrated with an initial sodium level of 178 mEq/L. Hypernatremia remained persistent despite massive hydration and the serum creatine phosphokinase level was 18,047 U/L after 3 days. Bone scintigraphy also showed findings consistent with rhabdomyolysis. Brain magnetic resonance imaging revealed extensive masses involving the pituitary gland and an intranasal biopsy confirmed meningioma. Polyuria, and low anti-diuretic hormone levels supported the diagnosis of central diabetes insipidus-induced hypernatremia. Desmopressin was administered intranasally and the patient's serum sodium and muscle enzyme levels were normalized.
Biopsy ; Brain ; Creatine Kinase ; Deamino Arginine Vasopressin ; Diabetes Insipidus ; Diagnosis ; Humans ; Hypernatremia ; Magnetic Resonance Imaging ; Male ; Meningioma* ; Middle Aged ; Pituitary Gland* ; Polyuria ; Radionuclide Imaging ; Rhabdomyolysis* ; Sodium

Positron emission tomography (PET) using 2-deoxy-2-[18F] fluoro-D-glucose (FDG) as a radioactive tracer is a useful technique for in vivo brain imaging. However, the anatomical and physiological features of the Harderian gland limit the use of FDG-PET imaging in the mouse brain. The gland shows strong FDG uptake, which in turn results in distorted PET images of the frontal brain region. The purpose of this study was to determine if a simple surgical procedure to remove the Harderian gland prior to PET imaging of mouse brains could reduce or eliminate FDG uptake. Measurement of FDG uptake in unilaterally adenectomized mice showed that the radioactive signal emitted from the intact Harderian gland distorts frontal brain region images. Spatial parametric measurement analysis demonstrated that the presence of the Harderian gland could prevent accurate assessment of brain PET imaging. Bilateral Harderian adenectomy efficiently eliminated unwanted radioactive signal spillover into the frontal brain region beginning on postoperative Day 10. Harderian adenectomy did not cause any post-operative complications during the experimental period. These findings demonstrate the benefits of performing a Harderian adenectomy prior to PET imaging of mouse brains.
Animals ; Brain/*metabolism/radionuclide imaging ; Fluorodeoxyglucose F18/*diagnostic use ; Frontal Lobe/metabolism/radionuclide imaging ; Harderian Gland/metabolism/radionuclide imaging/*surgery ; Mice ; Mice, Inbred BALB C ; Neuroimaging/standards/*veterinary ; Positron-Emission Tomography/*veterinary ; Radiopharmaceuticals/*diagnostic use

Von Hippel-Lindau (VHL) syndrome is a rare neoplastic disorder characterized by central nervous system (CNS) and visceral tumors. We here present 68Ga-labelled [1, 4, 7, 10-tetraazacyclododecane-1, 4, 7, 10-tetraacetic acid]-1-Nal3-Octreotide positron emission tomography computed tomography findings in a 52 year old female with VHL syndrome, demonstrating both CNS and visceral tumors.
Brain Diseases/radionuclide imaging ; Female ; Humans ; Kidney Diseases/radionuclide imaging ; Liver Diseases/radionuclide imaging ; Middle Aged ; Multimodal Imaging/*methods ; Organometallic Compounds/diagnostic use ; Pancreatic Diseases/radionuclide imaging ; Positron-Emission Tomography/*methods ; Tomography, X-Ray Computed/*methods ; von Hippel-Lindau Disease/*radionuclide imaging

Primary meningeal melanomatosis is a rare, aggressive variant of primary malignant melanoma of the central nervous system, which arises from melanocytes within the leptomeninges and carries a poor prognosis. We report a case of primary meningeal melanomatosis in a 17-year-old man, which was diagnosed with 18F-fluorodeoxyglucose (F-18 FDG) PET/CT, and post hoc F-18 FDG PET/MRI fusion images. Whole-body F-18 FDG PET/CT was helpful in ruling out the extracranial origin of melanoma lesions, and in assessing the therapeutic response. Post hoc PET/MRI fusion images facilitated the correlation between PET and MRI images and demonstrated the hypermetabolic lesions more accurately than the unenhanced PET/CT images. Whole body F-18 FDG PET/CT and post hoc PET/MRI images might help clinicians determine the best therapeutic strategy for patients with primary meningeal melanomatosis.
Adolescent ; Brain Neoplasms/*diagnosis/radionuclide imaging ; Fluorodeoxyglucose F18/diagnostic use ; Humans ; *Magnetic Resonance Imaging ; Male ; Melanoma/*diagnosis/radionuclide imaging ; Meningeal Neoplasms/*diagnosis/radionuclide imaging ; *Positron-Emission Tomography and Computed Tomography ; Radiopharmaceuticals/diagnostic use ; Whole Body Imaging

Sporadic spastic paraplegia (SSP) and hereditary spastic paraplegia (HSP) belong to a clinical and genetically heterogeneous group of disorders characterized by progressive spasticity and weakness in the lower extremities. The symptoms are associated with pyramidal tract dysfunction and degeneration of the corticospinal tracts. Parkinsonism is uncommon in SSP/HSP patients. However, both disorders are associated with damage to the nigrostriatal dopaminergic system. In the present study, the clinical features of patients with SSP/HSP were investigated, and nigrostriatal dopaminergic binding potential was assessed using dopamine transporter (DAT) single-photon emission computer tomography (SPECT). Nine patients with spastic paraplegia participated in the present study. The subjects underwent DAT SPECT using the agent [2-[[2-[[[3-(4-chlorophenyl)-8-methyl-8-azabicyclo[3,2,1]oct-2-yl]methyl](2-mercaptoethyl)amino]ethyl]amino]ethanethiolato (3-)-N2,N20,S2,S20]oxo-[IR-(exo-exo)])-[99mTc]technetium ([99mTc]TRODAT-1). The [99mTc]TRODAT-1 SPECT images of five patients appeared normal, whereas the images of four patients revealed reduced striatal ligand uptake. Among the four patients with reduced uptake, two had parkinsonism, and one exhibited periodic limb movements and restless leg syndrome. Our DAT SPECT imaging study shows that reduced DAT density may be observed in patients with parkinsonism. The results of the present study offer an explanation for the spectrum of spastic paraplegia symptoms and the progression of the disorder.
Adult ; Aged ; Brain/*radionuclide imaging ; Dopamine Plasma Membrane Transport Proteins/metabolism ; Female ; Humans ; Male ; Middle Aged ; Organotechnetium Compounds/diagnostic use ; Paraplegia/diagnosis/genetics/*radionuclide imaging ; Parkinsonian Disorders/complications/genetics/*radionuclide imaging ; Pyramidal Tracts ; Radiopharmaceuticals/diagnostic use ; Spastic Paraplegia, Hereditary/diagnosis/genetics/*radionuclide imaging ; Tomography, Emission-Computed, Single-Photon

We report on an angioedema patient with a genetic defect in complement 1 inhibitor, manifesting migraine-like episodes of headache, effective prophylaxis with Danazol, and triptan for a treatment of acute clinical episode. The patient was 44-yr-old Korean man with abdominal pain and headache, who was brought into the Emergency Department of Seoul National University Hospital, Seoul. He suffered from frequent attacks of migraine-like headache (3-7 per month), pulsating in nature associated with nausea. Severities were aggravated by activity and his headache had shown recent progression with abdominal pain. No remarkable findings were observed on radiologic examination, brain magnetic resonance images and intracranial and extracranial magnetic resonance angiography. Danazol 200 mg every other day was subsequently used. Following administration of Danazol, symptoms showed improvement and the patient was discharged. While taking Danazol, the migraine-like episodes appeared to be prevented for about 2 yr. At the eighth month, he suffered a moderate degree of migraine-like headache; however, administration of naratriptan 2.5 mg resolved his problem. A case of genetic defect of C1-INH deficiency presented with headache episodes, and was controlled by Danazol and triptan. It suggests that pathogenic mechanism of headache in hereditary angioedema may be mediated by the neurogenic inflammatory-like physiology of migraine.
Adult ; Angioedemas, Hereditary/*complications/diagnosis/*genetics ; Brain/radionuclide imaging ; Complement C1 Inhibitor Protein/*genetics/metabolism ; Danazol/therapeutic use ; Estrogen Antagonists/therapeutic use ; Humans ; Magnetic Resonance Angiography ; Male ; Migraine Disorders/*diagnosis/drug therapy/*etiology ; Piperidines/therapeutic use ; Tryptamines/therapeutic use ; Vasoconstrictor Agents/therapeutic use