technetium-tc-99m-exametazime and Cerebral-Hemorrhage

Topics: Adult; Aged; Atrophy; Brain; Cerebral Hemorrhage; Electroencephalography; Epilepsy; Humans; Magnetic Resonance Imaging; Middle Aged; Prospective Studies; Radiography; Radiopharmaceuticals; Retrospective Studies; Severity of Illness Index; Stroke; Technetium Tc 99m Exametazime; Time Factors

To evaluate the regional cerebral blood flow (rCBF) changes following IV mannitol bolus in patients with intracerebral hemorrhage (ICH).. In a hospital based randomized placebo controlled study, 21 CT proven ICH patients with Glasgow coma scale (GCS) score of 5 or more were subjected to clinical evaluation including GCS and Canadian Neurological stroke (CNS) scale. Cranial SPECT study was undertaken before and 60 min after 20% mannitol 100 ml IV in 20 min or sham infusion. The SPECT images were semi-quantitatively analyzed and asymmetry index of basal ganglia, frontal, parietal and occipital regions were calculated.. There were 12 patients in mannitol and nine in control group who were evenly matched for age, mean arterial blood pressure, GCS score and size of hematoma. Only one patient died in mannitol group. Following mannitol, GCS score improved in six, worsened in two and remained unaltered in four patients. In the control group, GCS improved in seven, worsened in none and was unchanged in two patients. SPECT studies revealed reduction in asymmetry index in basal ganglia in four, frontal region in six, parietal in four and occipital region in five patients in mannitol group. In control group, asymmetry index was reduced in basal ganglia in one, frontal and parietal region in three each and occipital region in five patients. These differences between control and study group were not significant.. Mannitol does not seem to significantly change the regional cerebral blood flow (rCBF) in ICH patients as evaluated by SPECT study.

Topics: Adult; Aged; Blood Circulation Time; Brain; Case-Control Studies; Cerebral Hemorrhage; Cerebrovascular Circulation; Diuretics, Osmotic; Female; Humans; Male; Mannitol; Middle Aged; Regional Blood Flow; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon; Trauma Severity Indices

Recent acute stroke trials have reported that intravenous streptokinase is associated with an increased risk of adverse outcomes. We aimed to study the effect of streptokinase on the nature of reperfusion and the relation between reperfusion and clinical outcome.. We studied 24 patients in the Australian Streptokinase Trial with acute middle cerebral cortical infarction using 99mTc-hexamethylpropyleneamine oxime single-photon emission CT. Eleven of the 24 patients were scanned before therapy and again 24 hours later. The remaining 13 were scanned once either before therapy (1 patient) or after therapy (12 patients). All patients had outcome scans after 3 months. Infarct hypoperfusion was measured with a validated volumetric technique. Neurological impairment and functional outcome were assessed with the Canadian Neurological Scale and the Barthel Index, respectively.. Fifteen patients received streptokinase and 9 received placebo. There was no difference in early reperfusion between streptokinase and placebo. However, streptokinase was associated with a greater amount of nonnutritional reperfusion than was placebo (P = .04). This luxury perfusion was associated with poor functional outcome (P = .02).. This study suggests that streptokinase augments luxury perfusion after stroke. Luxury perfusion is associated with a worse outcome, which might be due in part to reperfusion injury.

Topics: Adult; Aged; Aged, 80 and over; Cerebral Hemorrhage; Cerebral Infarction; Cerebrovascular Circulation; Cerebrovascular Disorders; Cohort Studies; Female; Humans; Male; Middle Aged; Organotechnetium Compounds; Oximes; Streptokinase; Technetium Tc 99m Exametazime; Thrombolytic Therapy; Time Factors; Tomography, Emission-Computed, Single-Photon; Treatment Outcome

Thrombolytic therapy was carried out on patients with acute ischemic stroke, and the risk of hemorrhagic transformation was evaluated from the residual cerebral blood flow (CBF) by pretherapeutic single-photon emission-computed tomography (SPECT).. Local intra-arterial thrombolytic therapy was carried out using urokinase or recombinant tissue plasminogen activator (rt-PA) within 6 hours from the onset in 34 patients in whom no hypodensity areas were observed on the initial computed tomography examination. In the 20 patients with carotid territory occlusion who underwent 99mTc-labeled hexamethylpropyleneamine oxime (99mTc-HMPAO) SPECT, the residual CBF of the ischemic region was evaluated semiquantitatively by calculating two parameters: the ischemic regional activity to cerebellar activity ratio (R/CE ratio) and asymmetry index (AI).. The occluded vessels could be recanalized in 22 (92%) of the 24 patients in the urokinase group and in all 10 of the patients in the rt-PA group. Hemorrhagic transformation appeared in 4 patients in the urokinase group and 3 patients in the rt-PA group. Among the 20 patients who underwent SPECT before the treatment, the residual CBF was lower in the 5 patients who developed hemorrhagic transformation than in the 15 who did not (P < .05). Hemorrhagic transformation occurred in all patients with R/CE ratio of less than 0.35 and AI of more than 1.5.. The risk of hemorrhagic transformation after recanalization of occluded vessels by local intra-arterial thrombolytic therapy was considered to be high when the pretherapeutic residual CBF was markedly reduced.

Topics: Acute Disease; Adult; Aged; Aged, 80 and over; Brain Ischemia; Cerebral Hemorrhage; Cerebrovascular Circulation; Female; Follow-Up Studies; Humans; Infusions, Intra-Arterial; Male; Middle Aged; Neurologic Examination; Organotechnetium Compounds; Oximes; Recombinant Proteins; Risk Factors; Technetium Tc 99m Exametazime; Thrombolytic Therapy; Tissue Plasminogen Activator; Tomography, Emission-Computed, Single-Photon; Urokinase-Type Plasminogen Activator

Topics: Aged; Brain Death; Cerebral Hemorrhage; Cerebrovascular Circulation; Humans; Male; Middle Cerebral Artery; Nasopharynx; Radiopharmaceuticals; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon; Tomography, X-Ray Computed; Ultrasonography, Doppler, Transcranial

Temporal-lobe lesions sometimes cause apnoeic attacks in infants, but they rarely cause apnoeic attacks in adults. An 80-year-old woman with a history of hypertension was admitted to hospital because of global aphasia and mild right hemiparesis. The admission head CT showed small subcortical haemorrhage in the left temporal lobe. Immediately after the CT, her respiratory rate decreased to 3/min, and her arterial blood gas analysis showed respiratory acidaemia without any evidence of airway obstruction or additional neurological deficits. Thus, she required artificial ventilation. Single-photon emission CT performed on the same day showed hyperperfusion in the left temporal region, but the electroencephalogram showed no epileptic spike. When mechanical ventilation was discontinued on the fourth hospital day, she was alert, and her respiratory rhythm was normal. This is the first report of a central apnoeic attack associated with intracerebral haemorrhage in the left temporal lobe in an adult patient. It is important to note that a small haematoma in the temporal lobe can trigger life-threatening apnoea, probably by cortical stimulation.

Topics: Aged, 80 and over; Aphasia; Cerebral Hemorrhage; Diagnosis, Differential; Dominance, Cerebral; Female; Humans; Regional Blood Flow; Sleep Apnea, Central; Technetium Tc 99m Exametazime; Temporal Lobe; Tomography, Emission-Computed, Single-Photon; Tomography, X-Ray Computed

Cerebral blood flow tests have increasingly been advocated for the confirmation of brain death (BD). Four-vessel angiography has been considered the most reliable investigation in the diagnosis of BD for >30 yrs, but it is invasive. (99m)Tc-HMPAO SPECT provides noninvasive, multiplanar imaging of brain tissue perfusion. The aim of this study was to check the reliability of SPECT compared with contrast angiography.. Prospective, blind study.. Neurointensive care unit of a university hospital.. Consecutive clinically brain dead patients with flat electroencephalogram.. BD was diagnosed according to Italian law. (99m)Tc-HMPAO SPECT and four-vessel angiography were performed in the same session; the rater of each investigation ignored the results of the other. Blood pressure, Sp(O2), and P(ECO2) were monitored throughout the study: any episode of hypoxia or hypotension caused exclusion of the patient from the study.. Twenty brain dead patients were enrolled. The cause of BD was head injury in seven cases (35%), subarachnoid hemorrhage in seven (30%), spontaneous hemorrhage in one (10%), brain tumors in two (10%), stroke in two (10%), and thrombosis of the sagittal sinus in one (5%). Both angiography and SPECT confirmed BD in 19 of 20 patients: angiography showed the absence of filling of intracranial arteries, while SPECT showed a picture of "empty skull." For the remaining patient, angiography showed slight and late filling of left vertebral, basilar, and posterior cerebral arteries, while SPECT showed faint traces of uptake in the posterior fossa on the right side and on the midline. For this patient, the tests were repeated 48 hrs later, and both showed the arrest of intracranial circulation, thus confirming BD.. Our results confirm the reliability of SPECT in the diagnosis of BD; because SPECT is noninvasive, it is a good candidate for the "gold standard" of diagnosis.

Topics: Adult; Aged; Aged, 80 and over; Brain Death; Brain Neoplasms; Cerebral Angiography; Cerebral Hemorrhage; Female; Humans; Intracranial Thrombosis; Male; Middle Aged; Prospective Studies; Radiopharmaceuticals; Stroke; Subarachnoid Hemorrhage; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

Carbon-11-L-methyl-methionine (11C-methionine) has been reported to be useful for evaluating brain tumors, but several other brain disorders have also shown signs of high methionine uptake. We retrospectively evaluated the significance of 11C-methionine uptake in cerebrovascular diseases, and also compared our results with those for 18F-FDG PET and 99mTc-HMPAO SPECT.. Seven patients, including 3 patients with a cerebral hematoma and 4 patients with a cerebral infarction, were examined. All 7 patients underwent both 11C-methionine PET and 99mTc-HMPAO SPECT, and 6 of them underwent 18F-FDG PET.. A high 11C-methionine uptake was observed in all 3 patients with cerebral hematoma. Increased 99mTc-HMPAO uptake was observed in 2 out of 3 patients, and all 3 patients had decreased 18F-FDG uptake. Of 4 patients with a cerebral infarction, high 11C-methionine uptake was observed in 3. Increased 99mTc-HMPAO uptake was also observed in one patient, whereas 3 patients had decreased 18F-FDG uptake.. We should keep in mind that high 11C-methionine uptake is frequently observed in cerebrovascular diseases. CVD should therefore be included in the differential diagnosis when encounting patients with a high 11C-methionine uptake.

Topics: Adolescent; Adult; Aged; Cerebral Hemorrhage; Cerebral Infarction; Female; Fluorodeoxyglucose F18; Hematoma; Humans; Male; Methionine; Middle Aged; Radiopharmaceuticals; Retrospective Studies; Technetium Tc 99m Exametazime; Tissue Distribution; Tomography, Emission-Computed; Tomography, Emission-Computed, Single-Photon

The brain distribution of 9mTc-hexamethylpropyleneamine oxime (HMPAO) correlates with regional brain perfusion, whereas 99mTc-ethyl cysteinate dimer (ECD) reflects not only perfusion but also the metabolic status of brain tissue. We compared 99mTc-ECD single-photon emission CT (SPECT) with 99mTc-HMPAO SPECT early after recanalization by local intraarterial thrombolysis (LIT) in patients with acute embolic middle cerebral artery occlusion. We also assessed the predictive value of 99mTc-HMPAO and 99mTc-ECD SPECT for the development of ischemic brain damage.. 99mTc-HMPAO and consecutive 99mTc-ECD SPECT studies were performed in 15 patients within 3 hours of LIT. The two SPECT studies were obtained independently using a subtraction technique. SPECT evaluation was performed using semiquantitative region-of-interest analysis. Noninfarction, infarction, and hemorrhage were identified by follow-up CT or MR imaging.. Forty-five lesions were identified (21 noninfarctions, 19 infarctions, and five hemorrhages). Regardless of 99mTc-HMPAO SPECT findings, lesions showing isoactivity (count rate densities of 0.9 to 1.1 as compared with the contralateral side) on 99mTc-ECD SPECT were salvaged. Lesions with hypoactivity (values < 0.9) on 99mTc-ECD SPECT developed irreversible brain damage. Hemorrhage appeared in lesions with both hyperactivity (values > 1.1) on 99mTc-HMPAO SPECT and hypoactivity on 99mTc-ECD SPECT.. The brain distribution of 99mTc-ECD in a reperfused area identified by 99mTc-HMPAO SPECT early after recanalization of acute ischemic stroke is dependent on cerebral tissue viability. By combining 99mTc-ECD and 99mTc-HMPAO SPECT, performed within the first few hours of LIT, it is possible to identify patients at risk for hemorrhagic transformation reliably.

Topics: Aged; Arterial Occlusive Diseases; Brain; Cerebral Hemorrhage; Cerebral Infarction; Cysteine; Female; Fibrinolytic Agents; Humans; Injections, Intra-Arterial; Intracranial Embolism; Magnetic Resonance Imaging; Male; Middle Aged; Organotechnetium Compounds; Predictive Value of Tests; Radiopharmaceuticals; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon; Tomography, X-Ray Computed

Lack of an effective treatment for spontaneous intracerebral haemorrhage (ICH) is partly because the mechanism of neuronal damage in ICH is not fully understood. Animal experiments have shown that there is a zone of ischaemia and oedema around the haematoma which can be reduced by early evacuation of the mass lesion. We set out to study Cerebral Blood Flow (CBF) changes in patients with ICH. We present data on 13 patients (mean age 60). SPECT scans were performed within 48 hours of ictus and 4-7 days later. Four patients had surgical evacuation of the clot; 9 were managed conservatively. The ratio of uptake of the isotope in the cerebral hemisphere containing the haematoma to the isotope uptake in the contra-lateral (un-affected) cerebral hemisphere was taken as an index of perfusion of the affected cerebral hemisphere. The perfusion index of the affected hemisphere improved between the first and the second scans in all the surgically treated patients; in the conservatively managed group, it was worse in 6 patients, the same in 1 and very slightly better in 2. There was an overall mean improvement of 3.87% in the surgical group, and an overall mean deterioration of 3.61% in the medical group. This data suggests that surgical evacuation of the clot may improve perfusion in the ipsilateral cerebral hemisphere in ICH. It underlines the importance of a prospective randomised trial to assess the value of surgery in patients with ICH. The Surgical Trial in Intracerebral Haemorrhage (STICH) is currently underway worldwide. We also describe the application of Difference Based Region Growing (DBRG) to SPECT image analysis. This method overcomes the difficulties posed by 1) the presence of a mass lesion and 2) surgical evacuation of haematoma.

Topics: Brain; Brain Edema; Cerebral Hemorrhage; Female; Humans; Male; Middle Aged; Postoperative Complications; Regional Blood Flow; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

Topics: Aged; Brain; Cerebral Amyloid Angiopathy; Cerebral Hemorrhage; Cerebrovascular Disorders; Granuloma; Humans; Male; Radiopharmaceuticals; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon; Vasculitis

A heart transplant patient treated with OKT3 developed a severe headache which worsened and was accompanied by a sudden decrease in the patient's consciousness level and aphasia when the treatment course was completed. CT was performed and was normal. SPET imaging with 99mTc-HMPAO of cerebral blood flow done 16 hours later revealed multiple and clear focal defects in the blood flow. Analysis of cerebral spinal fluid revealed aseptic pleocytosis. Five days after the completion of treatment, the symptoms remitted and a new control SPET 3 weeks later was completely normal. A diagnosis of neurotoxicity secondary to OKT3 administration was established.

Topics: Adult; Aphasia; Brain Abscess; Brain Edema; Cardiomyopathy, Dilated; Cerebral Hemorrhage; Cerebrospinal Fluid; Cerebrovascular Circulation; Confusion; Diagnosis, Differential; Headache; Heart Transplantation; Humans; Immunosuppressive Agents; Leukocytosis; Lymphocyte Activation; Male; Meningoencephalitis; Muromonab-CD3; Postoperative Complications; Radiopharmaceuticals; T-Lymphocytes; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

Hemorrhagic transformation (HT) is a common evolution of large-volume ischemic lesions, particularly of cardioembolic origin. We used transcranial Doppler ultrasound (TCD), single-photon emission computed tomography (SPECT) with 99mTc-hexamethylpropyleneamine oxime (HMPAO), and the Toronto Embolic Scale (TES) to decide (1) whether TCD, HMPAO-SPECT, and TES can improve on clinical and CT tests to predict spontaneous HT and (2) whether SPECT can help to predict the outcome of symptomatic HT.. Prognostic criteria included Canadian Neurological Scale (CNS) scores < or = 50 on admission, early ischemic changes on CT, M1 middle cerebral artery occlusion on TCD, the focal absence of brain perfusion on SPECT, and a high risk of cardiogenic embolism on TES.. In part 1, 85 consecutive patients admitted within the first 6 hours were studied. No patient received thrombolysis. HT was found in 11 patients (13%) at 3 to 5 days. Admission CNS and CT were not predictive of HT: odds ratios (95% confidence intervals) were 0.49 (0.18 to 1.23) (P = .1) and 0.88 (0.23 to 3.45) (P = .8), respectively, TCD, SPECT, and TES were significant predictors of HT (P < .05), as follows: TCD, 8.67 (1.42 to 70.59); SPECT, 17.40 (2.69 to 170.89); and TES, 18.13 (2.6 to 406.86). In part 2, 490 consecutive patients were studied and 21 (4%) had symptomatic HT, of which 12 had focal hypoperfusion on SPECT at 4 days after stroke onset and 9 had focal hyperperfusion. Patients with hypoperfusion had larger CT lesions (115 +/- 97 versus 42 +/- 29 cm3; P = .04) and poorer outcome at 2 weeks (CNS, 38 +/- 45 versus 96 +/- 10; P = .001), including death (6/12 versus 0/9; P = .04); compared with those with hyperperfusion on SPECT.. High risk of cardioembolism, M1 middle cerebral artery occlusion, and absence of collateral flow evaluated by TES, TCD, and SPECT help to identify patients at risk for spontaneous HT. Although TES was the most powerful predictor of HT, SPECT is the best single adjunct to the triage of clinical and CT tests. Patients with brain hyperperfusion on HMPAO-SPECT after symptomatic HT have better chances for recovery.

Topics: Anticoagulants; Cerebral Hemorrhage; Cerebral Infarction; Coronary Thrombosis; Humans; Intracranial Embolism and Thrombosis; Organotechnetium Compounds; Oximes; Prognosis; Prospective Studies; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon; Ultrasonography, Doppler, Transcranial

Tc-HMPAO isotope brain scans were performed in three patients who received hyperbaric oxygen treatment following carbon monoxide poisoning. Cerebral perfusion imaging provides an index of severity of the initial cerebral damage which correlated with outcome.

Topics: Adult; Brain; Carbon Monoxide Poisoning; Cerebral Hemorrhage; Cerebral Infarction; Cerebrovascular Circulation; Fatal Outcome; Female; Forecasting; Humans; Hyperbaric Oxygenation; Male; Organotechnetium Compounds; Oximes; Purpura; Radionuclide Imaging; Radiopharmaceuticals; Technetium Tc 99m Exametazime; Treatment Outcome

Single-photon emission computed tomography (SPECT) with 99mtechnetium-hexamethylpropylamineoxime (HMPAO) noninvasively shows brain perfusion in patients after acute stroke. However, the clinical significance of the increased HMPAO uptake remains unclear. In this study, consecutive patients with hemispheric hemorrhagic and ischemic stroke admitted to the hospital were evaluated prospectively. The increased uptake of HMPAO was determined by visual analysis of SPECT images. The pathogenic mechanism of ischemic stroke was determined using the clinical and computed tomography (CT) criteria including the Toronto Embolic Scale. Of the 500 consecutive patients with acute hemispheric stroke, SPECT was performed in 458 at a mean time 5 +/- 7 days after the onset of symptoms. A strong association was found between SPECT perfusion patterns and pathogenic subtypes of stroke (p < 0.0001). Thus, in 95% of patients with intracerebral hemorrhage the focal absence of perfusion was found, and 26% of lacunar infarctions presented with a normal SPECT appearance. The mean volume of lacunar lesions that did not produce significant abnormalities on SPECT was 2.5 +/- 1.2 ml. Increased HMPAO uptake was associated with a cardioembolic mechanism of stroke: High and mixed perfusion patterns were present subacutely in 29% of patients with cardioembolic stroke, compared to 15% of patients with other types of ischemic stroke (p < or = 0.0006). The increased uptake of HMPAO on SPECT as determined by visual analysis is associated with a cardioembolic mechanism of cerebral ischemia, which could be explained by glutathione-mediated trapping of the tracer during reperfusion and later in newly developed granulation tissue. HMPAO-SPECT may help in early management decisions since it indicates stroke pathogenesis and evolution.

Topics: Acute Disease; Aged; Brain; Brain Ischemia; Cerebral Hemorrhage; Cerebrovascular Circulation; Cerebrovascular Disorders; Female; Glutathione; Granulation Tissue; Humans; Intracranial Embolism and Thrombosis; Male; Middle Aged; Organotechnetium Compounds; Oximes; Prospective Studies; Reperfusion; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon; Tomography, X-Ray Computed

Topics: Adult; Cerebral Hemorrhage; Head Injuries, Closed; Hematoma; Humans; Magnetic Resonance Imaging; Male; Organotechnetium Compounds; Oximes; Technetium Tc 99m Exametazime; Time Factors; Tomography, Emission-Computed, Single-Photon; Tomography, X-Ray Computed

Nineteen patients with histologically diagnosed supratentorial cerebral neoplasms carried out CT and/or MRI, 201T1 SPECT and 99mTc-HM-PAO studies preoperatively. 99mTc-HM-PAO SPECT images revealed information about both tumoral perfusion and intracellular concentration of mediators converting 99mTc-HM-PAO to hydrophilic derivates (glutathione and other yet unknown factors) within viable tumoral cells while 201T1 SPECT images about permeability, extension of tumoral capillary network and viable tumoral cells presence. Basing on the different mechanisms of the tracer uptake, cerebral supratentorial tumors could be distinguished in three groups: 1) cerebral tumors presenting 201T1 very high uptake (201T1 index > 1.5) and homogeneous and high retention of 99mTc-HM-PAO (CBI > or = 1.05) (meningiomas, PRL adenoma); histologically these neoplasms presented very rich neoformed capillary network; 2) cerebral neoplasms with 201T1 high uptake (201T1 index > 1.5) and with inhomogeneous retention of 99Tc-HM-PAO (high grade gliomas amd metastasis); microscopically these tumors presented vascular proliferation, necrosis and high cellularity; 3) cerebral neoplasms characterized by 201T1 low uptake (201T1 index < 1.5) and lower retention of 99Tc-HM-PAO than cerebellum (low grade gliomas); at microscopic examination these neoplasms were characterized by absence of vascular proliferation and necrosis. These results suggest coupled 201T1/99Tc-HM-PAO SPECT is necessary to discriminate intra-axial from extra-axial tumor localization (lacking CT or MRI) and to detect the grade of malignancy of gliomas and tumor cell presence within necrotic areas.

Topics: Adult; Aged; Brain Neoplasms; Cerebral Hemorrhage; Female; Glioblastoma; Hematoma; Humans; Male; Middle Aged; Organotechnetium Compounds; Oximes; Technetium Tc 99m Exametazime; Thallium Radioisotopes; Tomography, Emission-Computed, Single-Photon; Tomography, X-Ray Computed

Topics: Aged; Amphetamines; Brain; Cerebellar Diseases; Cerebral Hemorrhage; Cerebrovascular Circulation; Humans; Iodine Radioisotopes; Iofetamine; Male; Organotechnetium Compounds; Oximes; Putamen; Seizures; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

Focal post traumatic mass lesions such as contusions and intracerebral haematomas are common, and often difficult for neurosurgeons to manage, because little is known of their pathophysiology. We have mapped cerebral blood flow, and studied small vessel ultrastructure at different time points within the first three weeks of head injury, in patients with these lesions. A zone of ischaemic brain is always present around these lesions, and persists for weeks or months. This accords with astrocyte swelling and microvascular compression seen on electron microscopy. Focal zones of hyperaemia were also present in 42% of patients, within the first two weeks of injury, and this appeared only within apparently normal tissue as judged by late MRI or CT.

Topics: Astrocytes; Biopsy; Blood-Brain Barrier; Brain; Brain Concussion; Brain Damage, Chronic; Brain Injuries; Capillaries; Cerebral Hemorrhage; Endothelium, Vascular; Follow-Up Studies; Humans; Hyperemia; Microscopy, Electron, Scanning; Muscle, Smooth, Vascular; Neurologic Examination; Organotechnetium Compounds; Oximes; Regional Blood Flow; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon

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

Traumatic intracerebral haematomas are a common neurosurgical emergency. Their management, particularly the role of surgical removal, is controversial. Deterioration often occurs late, and is unpredictable. Eight patients with traumatic intracerebral haematomas were admitted to the neurosurgical unit to monitor their clinical state. All were studied within 48 hours of admission with single photon emission computerised tomography (SPECT), using the recently introduced radionuclide 99Technetiumm-Hexamethyl propylene amine oxime (99Tcm-HMPAO). At the time of the SPECT study, all the patients had been clinically stable. Three patients remained so; in the other five, the conscious level deteriorated, necessitating craniotomy and evacuation of the haematoma. In all the patients, the SPECT studies demonstrated perfusion defects that corresponded to the location of the haematoma, as demonstrated by computerised tomography (CT). However, in the five patients who subsequently deteriorated, the perfusion defects seen on the SPECT scan appeared larger than the haematoma, as seen on the CT scan. In addition, there was widespread poor retention of 99Tcm-HMPAO in the ipsilateral hemisphere. These differences were quantifiable. Interestingly, these differences were present at a time when the patients were clinically stable, before their deterioration. It is concluded that SPECT studies with 99Tcm-HMPAO are of possible use as predictors of late deterioration in the management of traumatic intracerebral haematomas.

Topics: Adolescent; Adult; Aged; Brain Edema; Brain Injuries; Cerebral Hemorrhage; Craniotomy; Follow-Up Studies; Frontal Lobe; Hematoma; Humans; Male; Middle Aged; Organotechnetium Compounds; Oximes; Postoperative Complications; Radionuclide Imaging; Technetium Tc 99m Exametazime; Temporal Lobe; Tomography, X-Ray Computed

We performed single photon emission computed tomography (SPECT) and cerebral CT-scans in nine patients with hereditary cerebral amyloid angiopathy. CT-scans showed 23 focal hypodense lesions, 13 of which were visible on SPECT as a CBF-defect. One patient showed a CBF-defect on SPECT without CT-scan lesion and had a cerebral hemorrhage three months later in that particular region. In two additional patients, who were 50% at risk for this autosomal dominant disease, CBF-defects on SPECT, but no cortical lesions on CT-scan were found. CT-scans may be more sensitive than SPECT to detect chronic lesions caused by cerebral hemorrhages, but another possibility is that hemorrhages do not always lead to persistent CBF-defects. SPECT can show the effect of amyloid deposits on CBF before the angiopathy causes clinical symptoms.

Topics: Amyloidosis; Brain Diseases; Cerebral Hemorrhage; Cerebrovascular Circulation; Cerebrovascular Disorders; Female; Humans; Male; Middle Aged; Organotechnetium Compounds; Oximes; Single-Blind Method; Technetium Tc 99m Exametazime; Tomography, Emission-Computed, Single-Photon; Tomography, X-Ray Computed

A new radiotracer of cerebral perfusion, 99mTc-labelled hexamethylpropylene amine-oxime, has been tried in 78 subjects: 6 controls and 72 patients. Qualitatively, the distribution of this tracer in healthy subjects was very much the same as that obtained with a reference method using 133xenon inhalation. Quantitatively, there was no correlation between the real blood flow rate and the normalized cerebral uptake rate. On the other hand, the asymmetry indices obtained in controls (but also in 16 patients) correlated very closely with those obtained with 133xenon. Our first results in acute ischaemic diseases as well as in the evaluation of vasospasm or Alzheimer-like presenile dementia point to wide fields of application for the new compound. Unlike its predecessors, it is always available and will probably be used, without any logistic investment, with the standard equipment of all Nuclear medicine departments.

Topics: Adult; Aged; Aged, 80 and over; Alzheimer Disease; Brain Ischemia; Cerebral Hemorrhage; Cerebrovascular Circulation; Cerebrovascular Disorders; Female; Hematoma; Humans; Ischemic Attack, Transient; Male; Middle Aged; Organometallic Compounds; Oximes; Technetium Tc 99m Exametazime; Tomography, Emission-Computed

Technetium 99m hexamethylpropylene-amine oxime (HMPAO) is trapped by cerebral grey matter and the basal ganglia on its first pass through the brain. To assess its potential for studying patients with diseases of the basal ganglia, a study of 15 normal volunteers and 32 patients with known or suspected basal ganglia disease have been investigated. Sixteen patients with idiopathic Parkinson's disease showed no abnormality of the basal ganglia and varying degrees of cerebral underperfusion consistent with their intellectual status. Eight patients with Huntington's chorea showed a characteristic pattern of reduced or absent caudate nucleus uptake. Patients with diseases affecting the basal ganglia, such as Fahr's disease, Wilson's disease and hemibalismus had varying degrees of basal ganglia underperfusion as demonstrated by an HMPAO scan. We believe that this new radiopharmaceutical for the demonstration of cerebral blood flow shows significant potential for the diagnosis and management of patients with basal ganglia disease.

Topics: Adult; Aged; Aged, 80 and over; Basal Ganglia Diseases; Cerebral Hemorrhage; Hepatolenticular Degeneration; Humans; Huntington Disease; Middle Aged; Organometallic Compounds; Oximes; Parkinson Disease; Technetium; Technetium Tc 99m Exametazime; Thalamic Diseases; Tomography, Emission-Computed; Tomography, X-Ray Computed