technetium-tc-99m-exametazime and Precursor-Cell-Lymphoblastic-Leukemia-Lymphoma

Treatment of childhood leukemia may cause perfusion defects in the brain observed by SPECT. Perfusion MRI is a novel method to study brain perfusion which has not been used previously in this setting. This study was performed to compare SPECT with perfusion MRI in patients with acute lymphoblastic leukemia (ALL) after treatment.. Nineteen children or young adults underwent perfusion MRI at the cessation of treatment (n = 9) or 4-8 years after the treatment (n = 10). Seventeen of them also underwent SPECT at the time of MRI (within 0-3 days, n = 14) or a couple of months later (1.5-6 months, n = 3). SPECT images and relative cerebral blood volume (CBV) and cerebral blood flow (CBF) maps from perfusion MRI were analyzed visually. Relative CBV ratios of gray matter to white matter and thalamus to white matter were also calculated from the perfusion MRI.. Perfusion MRI did not show any focal perfusion defects, while small defects were observed by SPECT in five of 17 children (29%) in the basal, frontal or temporal areas on the left. No significant differences were observed by perfusion MRI in the relative CBV ratios in the different treatment groups. Time since treatment, age at diagnosis, brain irradiation, or findings in conventional MRI or SPECT did not have any effect on the relative perfusion values either.. SPECT may show small perfusion defects after treatment for childhood leukemia which are not visible by perfusion MRI. The clinical significance or prognosis of these defects is not known.

Topics: Adolescent; Adult; Brain; Cerebrovascular Circulation; Cerebrovascular Disorders; Child; Child, Preschool; Cytarabine; Female; Humans; Iatrogenic Disease; Magnetic Resonance Imaging; Male; Methotrexate; Precursor Cell Lymphoblastic Leukemia-Lymphoma; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon; Vincristine

Children with acute lymphoblastic leukemia (ALL) have impairment in their neuropsychological functioning and morphological changes in their brain after cranial irradiation and chemotherapy. The aim of this study was to identify possible brain perfusion defects caused by different types of treatment and their association with abnormalities in cerebral MRI and neuropsychological and clinical neurological findings.. Twenty-five consecutive children with ALL at the cessation of chemotherapy or after 1 yr were included. All of the children were given intravenous and intrathecal methotrexate for central nervous system therapy, 13 of them received cranial radiation therapy. Brain SPECT, cerebral MRI, clinical neurological and neuropsychological evaluations were performed.. Eleven of the 25 patients (44%) had brain perfusion defects in SPECT, eight of whom were treated with chemotherapy alone, and three received cranial irradiation. Two patients had small bilateral white matter changes on MRI; their brain SPECT scans were abnormal, although the findings were not related. Impairment of neuropsychological functioning was found in 86% of the patients tested. No significant difference between the patients with abnormal and normal SPECT were found. Those patients with abnormal SPECT were younger than those with normal SPECT and had received more frequent intravenous methotrexate infusions.. Brain SPECT detected perfusion defects that had occurred after treatment for childhood ALL. These defects may be related to frequent administration of a combination of intravenous and intrathecal methotrexate and/or young age.

Topics: Adolescent; Antimetabolites, Antineoplastic; Brain; Child; Child, Preschool; Cranial Irradiation; Cysteine; Female; Humans; Magnetic Resonance Imaging; Male; Methotrexate; Neurologic Examination; Organotechnetium Compounds; Oximes; Precursor Cell Lymphoblastic Leukemia-Lymphoma; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

Chemotherapy of the central nervous system may cause neurotoxicity in children with acute lymphocytic leukemia. We evaluated regional blood flow in a 6-year-old child presenting with akinetic mutism, using 99mTc-HMPAO single photon emission tomography (SPECT) following high-dose intravenous methotrexate therapy. While findings in X-ray computerized tomography were decreased density in bilateral basal ganglia and thalamic nuclei with diffusely decreased attenuation of the periventricular white matter, a global, frontal dominant profoundly abnormal perfusion pattern involving both gray and white matter was observed in the SPECT study. Treatment of the central nervous system with high dose intravenous chemotherapy may cause profound abnormalities in white and gray matter blood flow and early assessment of the neurotoxicity may be identified by 99mTc-HMPAO SPECT in the pediatric age group.

Topics: Akinetic Mutism; Antimetabolites, Antineoplastic; Antineoplastic Combined Chemotherapy Protocols; Brain; Child; Dominance, Cerebral; Dose-Response Relationship, Drug; Female; Frontal Lobe; Humans; Infusions, Intravenous; Methotrexate; Precursor Cell Lymphoblastic Leukemia-Lymphoma; Regional Blood Flow; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

Imaging findings from a single case of disseminated infection with Fusarium are presented. This common fungus has been reported as a rare pathogen to the immunocompromised. Disseminated foci were identified on a Tc-99m HMPAO labeled WBC study. Two foci were localized to the proximal tibia using MRI. In this case, imaging was more sensitive to the extent of disease than physical examination, and it also provided a more precise estimate of disease progression than clinical evaluation alone. Imaging offers potential to track regression and to identify early recurrence. This is especially valuable because infection with Fusarium tends to be indolent.

Topics: Adult; Fusarium; Humans; Immunocompromised Host; Leukocytes; Magnetic Resonance Imaging; Male; Mycoses; Organotechnetium Compounds; Oximes; Precursor Cell Lymphoblastic Leukemia-Lymphoma; Radionuclide Imaging; Sensitivity and Specificity; Technetium Tc 99m Exametazime; Tibia

Topics: Adolescent; Antineoplastic Combined Chemotherapy Protocols; Asparaginase; Cerebral Hemorrhage; Female; Follow-Up Studies; Hematoma; Humans; Intracranial Embolism and Thrombosis; Magnetic Resonance Imaging; Organotechnetium Compounds; Oximes; Precursor Cell Lymphoblastic Leukemia-Lymphoma; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon