Normal ranges of renal function parameters for 99mTc-EC renal scintigraphy.

BACKGROUND: Dynamic renal scintigraphy remains the recognized method for evaluation of kidney function and perfusion. Although there is an extensive body of knowledge about the use of technetium-99m-mercaptoacetyltriglycine (99mTc-MAG3), much less has been written about renal technetium-99m-ethylenedicysteine (99mTc-EC) scintigraphy. The aim of this study was to determine the normal value of renal function parameters in 99mTc-EC dynamic renal scintigraphy: Tmax and T1/2. The effects of age, left or right side in the retroperitoneal space, and sex on those parameters were examined. MATERIAL AND METHODS: The research was conducted on 123 patients (F/M: 70/53; aged 2-71; averaging 14.8 years of age) with at least one normal kidney. A total of 194 healthy kidneys were examined, including pediatric kidneys. RESULTS: According to this study, the normal value of Tmax is 2.85 min (± 1.16) and T1/2 is 8.7 min (± 3.61). Values calculated for pediatric studies are Tmax is 2.81 (± 1.16) and T1/2 is 8.63 (± 3.71). CONCLUSIONS: The normal value of secretory and excretory renal function parameters was calculated. Although the value is slightly lower for children, this is not statistically significant, as globally there are no differences between the kidney-location sides and sexes for any parameter.

Patterns of vascular graft infection in 18F-FDG PET/CT.

BACKGROUND: 18F-FDG PET/CT has become an important tool in diagnosis of prosthetic vascular graft infections (PVGI). The aim of the study was to identify the patterns of vascular graft infection in 18F-FDG PET/CT. MATERIAL AND METHODS: The study was performed in 24 patients with vascular graft infection, in 17 patients implanted in an open surgery mode and in 7 patients by endovascular aortic repair (EVAR). Vascular prostheses were evaluated by two visual scales and semi-quantitative analysis with maximum standardized uptake values (SUV max). RESULTS: In the 3-point scale: 23 patients were in grade 1 and one patient was in grade 2. In the 5-point scale: 19 patients were in grade 5 with the highest activity in the focal area, 4 patients were in grade 4 and one patient in grade 3. The visual evaluation of 18F-FDG PET/CT study revealed that peri-graft high metabolic activity was associated with occurrence of morphological abnormalities (n = 21) like gas bubbles and peri-graft fluid retention or without abnormal CT findings (n = 3). The presence of the gas bubbles was linked to higher uptake of 18F-FDG (p < 0.01, SUVmax 11.81 ± 4.35 vs 7.36 ± 2.80, 15 vs 9 pts). In EVAR procedure, the highest metabolic activity was greater than in classical prosthesis (SUVmax 21.5 vs 13). CONCLUSIONS: 18F-FDG PET/CT is a very useful tool for assessment of vascular graft infections. CT findings like gas bubbles, or peri-graft fluid retention were associated with significantly higher glucose metabolism; however, in some cases without anatomic alterations, increased metabolic activity was the only sign of infection.

Therapeutic use of carbohydrate-restricted diets in an autistic child; a case report of clinical and 18FDG PET findings.

The ketogenic diet (KD) is a high-fat, adequate-protein, and low-carbohydrate diet that has been used successfully in the treatment of refractory epilepsies for almost 100 years. There has been accumulating evidence to show that the KD may provide a therapeutic benefit in autism spectrum disorders, albeit by a yet-unknown mechanism. We report a case of a 6-year-old patient with high-functioning autism and subclinical epileptic discharges who responded poorly to several behavioural and psychopharmacological treatments. The patient was subsequently placed on the KD due to significant glucose hypometabolism in the brain as revealed by an 18FDG PET. As soon as one month after starting the KD, the patient's behavior and intellect improved (in regard to hyperactivity, attention span, abnormal reactions to visual and auditory stimuli, usage of objects, adaptability to changes, communication skills, fear, anxiety, and emotional reactions); these improvements continued until the end of the observation period at 16 months on the KD. The 18FDG PET, measured at 12 months on the KD, revealed that 18F-FDG uptake decreased markedly and diffusely in the whole cerebral cortex with a relatively low reduction in basal ganglia in comparison to the pre-KD assessment. It warrants further investigation if the 18FDG PET imaging could serve as a biomarker in identifying individuals with autism who might benefit from the KD due to underlying abnormalities related to glucose hypometabolism.

Role of 18F-FDG PET/CT in the diagnosis of inflammatory and infectious vascular disease.

This review article discusses the utility of 18F-FDG PET/CT in diagnosis and management of vascular disease. We stress usefulness of this method in large vessel inflammation and infection. In our work we based on the literature analysis and clinical cases diagnosed in our institution by use of 18F-FDG PET/CT. The literature exploration was focusing on vascular inflammation and infections and 18-FDG PET. The search was performed on PubMed database and cross referencing. We present the practical review with several images of vascular diseases like: Takayasu arteritis, giant cell arteritis, vascular graft infections, abdominal aortic aneurysm infections and cases of aortitis and periaortitis. From this work inflammation associated with atheromatic process and vulnerable atherosclerotic plaque we excluded. 18F-FGD PET/CT is a sensitive metabolic, reliable, non-invasive imaging modality suitable for diagnosis and follow-up of inflammation and infections in vascular system.

Multiple and solitary skeletal muscle metastases on 18F-FDG PET/CT imaging.

OBJECTIVE: The aim of this study was to investigate the features and patterns of skeletal muscle metastases (SMM) detected with F-fluorodeoxyglucose (F-FDG) PET/computed tomography (PET/CT). PARTICIPANTS AND METHODS: Our database was analyzed for patients with pathologically proven malignancy, who underwent F-FDG PET/CT in our institution. The patients with SMM were included in the study group on the basis of the final diagnosis confirmed by follow-up or histopathology. Images were acquired using a PET/CT system Biograph mCT S(64)-4R. CT was performed without contrast enhancement. RESULTS: The selected group included 31 patients (1.7% of the database, which consisted of 1805 patients). A total of 233 lesions were found. The prevalence of SMM evaluated in specific primary malignancies was the highest in melanoma (6.9%), followed by carcinoma of unknown primary (4.4%), colorectal cancer (4.1%) and lung cancer (2.8%). Three patterns of skeletal muscle metastatic involvement were observed: multiple SMM accompanied by other metastases (64.5%), solitary lesion associated with other metastases (29%) and isolated intramuscular lesions (two cases, 6.5%). Isolated SMM represented recurrence of the malignant disease. In patients with extraskeletal metastases, solitary or multiple SMM did not affect tumor staging. CONCLUSION: Solitary SMM are less common than multiple on F-FDG PET/CT imaging. SMM are usually associated with other metastases and do not affect tumor staging. The cases of isolated SMM are very rare. Nevertheless, in patients with a diagnosis of malignant disease, a solitary, F-FDG avid intramuscular focus should be suspected to represent metastasis.

Early brain perfusion improvement after ventriculoperitoneal shunt surgery in patients with idiopathic normal pressure hydrocephalus evaluated by 99mTc-HMPAO SPECT - preliminary report.

BACKGROUND: Idiopathic normal pressure hydrocephalus (iNPH) is a clinical syndrome that consists of the triad: gait disturbance, mental deterioration and urinary incontinence associated with normal cerebrospinal fluid pressure (CSF), without pre-existing abnormalities. The most popular treatment option is surgical implantation of a shunt. Brain perfusion increase occurring months or years after successful shunt surgery is well described in the literature. Early improvement of perfusion is not well documented. Therefore, the objective of the present study was to determine patterns of brain perfusion changes 3-6 days after the ventriculoperitoneal shunting in patients with iNPH by using 99mTc-HMPAO SPECT. MATERIAL AND METHODS: Sixteen patients with iNPH (9 women, 7 men, mean age 64.1 ± 12.7 years) who underwent ventriculoperitoneal shunt surgery were included into the study group. Indications for implanting a shunt were based on clinical history, neuroimaging and CSF dynamic studies with an infusion test. Brain perfusion SPECT was performed 1-2 days before and 3-6 days after the surgical treatment. For comparison of perfusion before and after the surgery SPECT scans were assessed visually and semiquantitatively with voxel based analysis. RESULTS: No side effects were observed after the surgery. Brain perfusion improvement after shunting was observed in 10 patients (62.5%). Patterns of perfusion changes varied between patients, with combinations of different bilateral and lateralized brain regions involved. Perfusion increased in the whole brain (3 patients), in the right cerebral hemisphere (1 patient) or in the separate cerebral regions (6 patients): frontal, parietal, temporal, cerebellum, cingulate gyrus. Perfusion improvement was predominantly observed in the frontal lobes: right frontal (3 cases, 18.8%), left frontal (3 cases, 18.8%). CONCLUSIONS: Cerebral perfusion is recovered promptly after ventriculoperitoneal shunt surgery in about 60% of patients with iNPH. This improvement may be global or regional in different cerebral areas with prevalence of the frontal lobes.

Complex Regional Pain Syndrome type I with atypical scintigraphic pattern--diagnosis and evaluation of the entity with three phase bone scintigraphy. A case report.

Complex Regional Pain Syndrome (CRPS) is a neurological disorder of unknown etiology which may lead to severe disability. Its diagnosis is very difficult and based on diagnostic criteria which have been changing over last years. Still, there is no golden standard in diagnosis of this entity. Three-phase bone scan is a widely used diagnostic modality which has been proved useful in CRPS evaluation. The syndrome may present various scintigraphic patterns. Different diagnostic modalities can also be helpful when CRPS is suspected including plain film radiography, magnetic resonance imaging and ultrasonography. Multidisciplinary approach is necessary for proper and quick diagnosis. We present a case of CRPS in 12-year-old girl in whom the diagnosis was based on the bone scan.

Cardiac sympathetic hyperactivity in chronic kidney disease--a comparison between haemodialysis and peritoneal dialysis patients.

BACKGROUND: The effect of renal replacement therapy on cardiac sympathetic function in patients with chronic kidney disease has not yet been completely elucidated. The aim of this study was to evaluate the impact of renal replacement therapy on the activity of cardiac sympathetic nervous system. MATERIAL AND METHODS: Thirty-four patients with chronic kidney disease were studied: 14 patients (6 men, mean age 48 ± 11 years) were receiving peritoneal dialysis (PD) and 20 patients (20 men, mean age 52 ± 10 years) were receiving haemodialysis (HD). Patients with diabetes and heart failure were excluded from the study. All patients underwent resting gated myocardial perfusion and ¹²³I-mIBG myocardial scintigraphy from which early and late heart to mediastinum ratios (HRM) and myocardial washout rate (WR) values were calculated. RESULTS: PD and HD patients did not differ with respect to left ventricular ejection fraction (52 ± 9% vs. 57 ± 7%) and summed rest score (3.8 ± 2.4 vs. 3.5 ± 0.3). Similarly, early (1.89 ± 0.23 vs. 1.87 ± 0.27) and late (1.76 ± 0.47 vs. 1.74 ± 0.25) HMR, and washout rate (35.5 ± 15.8% vs. 31.3 ± 9.4%) were not significantly different between the two groups of patients. CONCLUSIONS: These results suggest that the applied method of renal replacement therapy has no significant influence on global activity of cardiac sympathetic nervous system.

Quantitative evaluation of crossed cerebellar diaschisis, using voxel-based analysis of Tc-99m ECD brain SPECT.

BACKGROUND: In the recent literature there is no consensus regarding the relationships between crossed cerebellar diaschisis (CCD) with the primary lesion size, severity or location. Thus, the aim of the present study was to investigate relationship between the size and severity of cerebral lesions and CCD in patients with chronic stroke, using voxel-based analysis of Tc-99m ECD single-photon emission computed tomography (SPECT). MATERIAL AND METHODS: We retrospectively reviewed data of 57 patients with chronic ischemic lesions localized unilaterally in the cerebral hemisphere. SPECT evaluation was performed with the voxel-based analysis. The percentage inter-hemispheric asymmetry index (AI) and the volume of abnormal clusters of voxels (CV) were ascertained for hypoperfusion in the supratentorial lesion and contralateral cerebellum. RESULTS: CCD was present in 35.1% cases. In Group CCD (+), the CV and AI of supratentorial hypoperfusion (median 128.1 ml and 21.9%, respectively) were significantly higher compared with Group CCD(-) (median 41.4 ml and 18.0%, respectively). Statistically significant correlation was found between CV of supratentorial and cerebellar perfusion defects (r = 0.4; p < 0.05), between AI of supratentorial and cerebellar perfusion defects (r = 0.6; p < 0.05) and between CV of supratentorial defect and AI of cerebellar perfusion defects (r = 0.6; p < 0.05). CONCLUSIONS: Our data suggest, that in the chronic stage of stroke, the size and severity of the supratentorial lesion are determinants of CCD, correlating with the degree of cerebellar hypoperfusion.

Usefulness of 99mTc-ECD brain SPECT with voxel-based analysis in evaluation of perfusion changes early after carotid endarterectomy.

BACKGROUND: Association between preoperative perfusion pattern and reperfusion after carotid endarterectomy (CEA) is an important yet unexplored topic. Therefore, the aim of our study was to determine whether 99mTc-ECD single-photon emission computed tomography (SPECT) performed before carotid endarterectomy in patients with internal carotid artery (ICA) stenosis may be helpful in predicting early perfusion changes after revascularization. MATERIAL/METHODS: The examined group consisted of 30 patients (mean age 67.4±9.6 years) with ICA stenosis who underwent CEA. Infarction was demonstrated on computed tomography (CT) in 12 cases. Brain perfusion SPECT was performed 1-3 days before CEA and 3-5 days after the surgery. Voxel-based analysis was carried out with Brain SPECT Quantification software. For evaluation of preoperative interhemispheric asymmetry of perfusion, the percentage asymmetry index (AI) was calculated. For comparison of perfusion before and after CEA, the percentage relative difference (RD) was computed. RESULTS: Before CEA, cerebral hypoperfusion was seen in 26 cases, including 15 participants with normal CT. After CEA, the following changes of perfusion were observed: perfusion increase n=18 (ipsilateral and bilateral), deterioration n=1, mixed patterns n=2, no change n=9. In patients with preoperative ipsilateral hypoperfusion and perfusion increase after CEA, AI correlated significantly with RD (r=0.48, p=0.04). CONCLUSIONS: Our results suggest that perfusion increase 3-5 days after CEA is higher in patients with greater ipsilateral asymmetry index. Evaluation of preoperative AI may help to identify patients in whom rapid reperfusion is more likely.

Evaluation of somatostatin receptors in large cell pulmonary neuroendocrine carcinoma with 99mTc-EDDA/HYNIC-TOC scintigraphy.

OBJECTIVE: Large cell pulmonary neuroendocrine carcinoma (LCNEC) is a poorly differentiated and high-grade neoplasm. It is positioned between an atypical carcinoid and small cell neuroendocrine carcinoma of the lung in a distinct family of pulmonary neuroendocrine tumors. The aim of our study was to detect somatostatin receptors in this uncommon malignancy and to evaluate the sensitivity of somatostatin receptor scintigraphy (SRS) in LCNEC staging. METHODS: We analyzed data of 26 patients (mean age: 61.5±7.9 years) with histologically confirmed diagnosis of LCNEC, including 18 cases not treated surgically and eight patients after the resection of the primary tumor. SRS was carried out with technetium-99m ethylene diamine-diacetic acid/hydrazinonicotinyl-Tyr3-octreotide (Tc-TOC). A visual analysis of scintigraphic images was done with reference to conventional imaging modalities (computed tomography and bone sicintigraphy). RESULTS: SRS sensitivity for the detection of primary lesions, supradiaphragmatic metastases, and infradiaphragmatic metastases was 100, 83.3%, and 0%, respectively. Five out of 13 metastases to the liver appeared on SRS as photopenic foci, visible on the background of physiological hepatic activity. Only one of the nine metastases to the skeletal system was found by SRS with sensitivity as low as 11.1%. The overall SRS sensitivity for the detection of secondary lesions and of all lesions was 54.8 and 62.2%, respectively. CONCLUSION: Within a rather large series of LCNEC, the primary tumor showed an uptake of Tc-TOC in all cases, whereas some metastases did show Tc-TOC uptake and some others did not.

99mTc-EDDA/HYNIC-TOC somatostatin receptor scintigraphy in daily clinical practice.

BACKGROUND: This study aimed to assess the impact of 99mTc-EDDA/HYNIC-TOC (99mTc-TOC) somatostatin receptor scintigraphy (SRS) in clinical practice. MATERIAL/METHODS: One hundred seventeen patients were divided into 6 groups: 1, initial detection and localization of suspected neuroendocrine tumor (NET); 2, tumor staging before therapy; 3, staging of NET of unknown origin, 4, restaging after surgery of primary tumor; 5, diagnosis of solitary pulmonary nodules (SPNs), and 6, follow-up after "cold" somatostatin analogues treatment. RESULTS: In group 1, clinical suspicions were not confirmed in any of the patients; in group 2, most of the primary lesions showed overexpression of somatostatin receptors (SSRT); in group 3, the primary tumor was not identified in any of the patients; in group 4, recurrences were depicted in 7 out of 47 patients; in group 5, only 1 malignant SPN was detected, and in group 6, regression of primary mass and metastases were seen on follow-up SRS in 1 patient. CONCLUSIONS: 99mTc-TOC SRS is useful in staging of SSRT-overexpressing tumors of known and unknown primary origin, as well as in restaging after primary tumor surgery. This method is less effective in detecting suspected NET and assessing SPNs. Further investigation is necessary to evaluate the usefulness of SRS in monitoring patients after biological treatment.

Changes of brain perfusion after endovascular embolization of intracranial arteriovenous malformations visualized by 99mTc-ECD SPECT.

OBJECTIVE: Published data describing scintigraphic evaluation of perfusion changes in patients with cerebral arteriovenous malformations (AVMs) after embolization are very scarce. The aim of our study was to evaluate these changes by using Tc-ethyl cysteinate dimer single photon emission computed tomography. MATERIALS AND METHODS: The examinations were performed in 20 patients before and after the treatment. Voxel-based analysis was used for semiquantitative assessment of single photon emission computed tomography. Hypoperfusion in basal single photon emission computed tomography was diagnosed when asymmetry index was higher than 10% in a cluster volume (CV) greater than 10.0 ml. The change of perfusion between basal and control studies was considered significant when relative difference (RD) was higher than 10% in a CV greater than 10 ml. RESULTS: Obliteration of AVMs was total or nearly total in 12 patients and partial in 8 patients, No serious complications were observed after the procedure. Before embolization hypoperfusion in the region of an AVM was seen in 17 cases, perfusion defects in areas distant from an AVM were found in 12 patients. After embolization, perfusion around an AVM deteriorated in 11 patients (CV=10.7-68.7 ml, mean 28.6+/-18.4, RD=14-26%, mean 17.8+/-4.5). Improvement was seen in three cases (CV=13.7-17.7 ml, mean 16+/-2, RD=16.5-20.1%, mean 18.2+/-1.8). Perfusion deterioration in areas distant from AVMs was found in nine cases, improvement in three cases. CONCLUSION: The changes of perfusion caused by endovascular embolization of AVM can rely on both deterioration and improvement, and occur in the parenchyma surrounding the AVM and in the distant regions of the brain. Although deterioration of perfusion indicated that more frequent follow-up was necessary, it was not related with serious complications in our group of patients.

Radiation synovectomy with 90Y colloid in the therapy of recurrent knee joint effusions in patients with inflammatory joint diseases.

The aim of this study was to assess the effectiveness of radiation synovectomy (RSV) in the treatment of recurrent joint effusions, using 90Y in patients with chosen inflammatory joint diseases. The group of treated patients consisted of 30 people. Qualification for the treatment was based on clinical assessment, three-phase bone scintigraphy (BS3) and biochemical analysis. Intra-articular injection of 90Y was performed. Biochemical analysis was repeated after 48 h, 4 and 24 weeks, whereas BS3 was repeated after 24 weeks. Changes in the second phase of BS3 were assessed visually, using a four-degree scale and in the third phase, semiquantitatively with J/B ratio. The changes in the blood pool phase before RSV were 3.4 +/- 0.6 and after the therapy 2.00 +/- 0.8 (P < 0.001). The J/B ratio was: before RSV 2.58 +/- 08; after treatment 2.09 +/- 0.9 (P < 0.05). RSV is an effective method to treat recurrent effusions in patients with RA and SPA.

Evaluation of the left ventricular hemodynamic function and myocardial perfusion by gated single photon emission tomography, in patients with type 1 diabetes mellitus; prodromal signs of cardiovascular disease after four years.

The aim of this study was to assess the changes in hemodynamic function and myocardial perfusion of the left ventricle occurring in patients with type 1 diabetes mellitus (DM1) 47-49 months after the first assessment. We have studied 20 asymptomatic patients, five females and 15 males, aged 22-46 y. The patients were under intensive insulin treatment and had normal electrocardiogram (ECG) at rest. In all patients gated single photon emission tomography (GSPET) was performed at rest and after exercise (examination I). After 47-49 months this test was repeated (examination II). GSPET was performed 60 min after the intravenous injection of 740 MBq of technetium-99m 2-methoxy-isobutyl-isonitrile ((99m)Tc-MIBI), using a dual-headed gamma-camera. Left ventricular ejection fraction (LVEF), end diastolic volume (EDV) and end systolic volume (ESV) were calculated using quantitative GSPET (QGS). The intensity of perfusion defects was also evaluated based on a four degree QGS scale. Our results were as follows: a) In examination I, performed at rest: LVEF was 56.1%+/-7.5%, EDV 96.9+/-25.8 ml and ESV 42.6+/-16.3 ml. b) In examination I at stress: LVEF was 57.2%+/-7.5%, EDV 94.1+/-24.0 ml and ESV 40.5+/-15.5. c) In examination II performed at rest: LVEF was 58.1%+/-6.5%, EDV 112.1+/-26.1 ml and ESV 46.6+/-14.9 ml and d) In examination II at stress: LVEF 57.8%+/-5.6%, EDV 107.9+/-27.4 ml and ESV 44.9+/-14.4 ml. Significant differences were found between examinations I and II, regarding: a) EDV at rest (P<0.001) and at stress (P<0.001) and b) ESV at rest (P<0.05) and at stress (P<0.005). Correlation analysis revealed significant correlation between LVEF at rest and at stress both in examination I (r=0.83; P<0.001) and also in examination II (r=-0.897; P<0.001). Intensity of myocardial perfusion defects in examination I at rest and at stress was: 1.68+/-0.5 and 2.2+/-0.6 degrees respectively. Intensity of myocardial perfusion defects in examination II at rest and at stress was: 1.75+/-0.4 and 2.2+/-0.5 respectively. No significant differences in the intensity of these perfusion defects were found. EDV both at rest and at stress was significantly higher in examination II as compared with the examination I study. Similar, but less pronounced changes of ESV were found. This study confirms other authors' observations on LV, EDV and LV, ESV and also that the percentage of asymptomatic DM1 patients having silent myocardial ischemia is high as was in all our patients. Nevertheless, in the current literature, we were unable to find a study similar to the present one, comparing basal and after four years LV functional GSPET data, in asymptomatic DM1 patients. In conclusion, myocardial perfusion GSPET was useful as a screening test in DM1 patients in showing four years after the basal study, prodromal signs of cardiovascular disease, especially increase of left ventricular volumes and silent myocardial ischemia, in these patients. Our research on the above protocol is being continued.

Bone turnover markers and bone scintigraphy in the evaluation of the skeletal metastases.

BACKGROUND: The aim of this study was evaluation of the clinical usefulness of bone scintigraphy and of serum bone turnover marker levels in the assessment of skeletal metastases. MATERIAL AND METHODS: We investigated 60 patients with suspected skeletal metastases. Serum level of bone-formation marker: amino-terminal propeptide of type I procollagen (PINP) and a bone-degradation marker: carboxy-terminal telopeptide of type I collagen (ICTP) were assessed with radioimmunoassays. Bone MDP-99m-Tc scans were performed as well. RESULTS: Hot spots were showed in 72% of patients. According to bone scintigraphy the patients were divided in to 3 groups: Group I - without hot spots (n=16; 26%), Group II up to 10 hot spots (n=25; 42%) and Group III more that 10 hot spots (n=19; 32%). Mean serum level of ICTP was significantly higher in Group II than in Group I (p< 0.05), as well as in Group III compared to Group II (p< 0.001) and in Group III compared to Group I (p< 0.001). There is only one significant relationship in PINP levels - between Groups II and III. CONCLUSIONS: The levels of bone pathological degradation (ICTP) and bone formation reflect the metastatic disease extent in bone. Serum ICTP level is more useful in staging metastasis. Significantly higher PINP reflects only a much disseminated process.

[SPECT imaging of cerebral arteriovenous angiomas. A preliminary report]. / Obrazowanie malformacji tetniczo-zylnych mózgu technika SPECT. Doniesienie wstepne.

BACKGROUND AND PURPOSE: The purpose of this study was to demonstrate scintigraphic evaluation of cerebral perfusion in patients with intracranial hemangiomas. MATERIAL AND METHOD: The examination was carried out in 12 patients aged from 12 to 67 years. In all the patients cerebral angiomas were previously diagnosed and all of them were qualified for intravascular embolization. Brain scintigraphy was performed after IV injection of 99mTcECD and included the dynamic phase with images obtained every 2 seconds for 1.5 minutes and SPECT imaging. The semiquantitative analysis of regional cerebral blood flow was based on the comparison between activity in two symmetrical regions of interest. Cerebral angiography combined with intravascular embolization followed the scintigraphic examination. RESULTS: Based on angiograms, the size of the nidus was estimated at 1.0 to 9.0 cm. In 8 patients the dynamic study showed an increased tracer accumulation in the region of angioma. On SPECT images the nidus was visualized as focally decreased perfusion in all cases. A decreased tracer accumulation in the area adjacent to the nidus was detected in 8 patients. The ratio of activity in the region of angioma to activity in normally perfused tissue calculated using the semiquantitative analysis was 52% to 89%. CONCLUSIONS: SPECT images and dynamic phase of cerebral perfusion scintigraphy allow perfusion changes caused by the presence of intracranial angiomas to be identified.

Diagnostic value of cerebral perfusion scintigraphy in evaluation of intracranial arteriovenous malformations--preliminary report.

BACKGROUND: Arteriovenous malformations (AVM) markedly alter the distribution of the regional cerebral blood flow, as they consist of abnormal arteries and veins with no resistance vessels between them. The aim of this study was to the evaluate diagnostic utility of cerebral perfusion scintigraphy (dynamic phase and SPECT) in patients with AVM. MATERIAL AND METHODS: Nineteen patients were examined. All the patients had been previously diagnosed with AVM and qualified for intravascular embolization. Brain scintigraphy was performed with 99mTc-ECD and included dynamic phase and SPECT imaging. The regional blood flow was evaluated visually and semi quantitatively, based on comparison between the activity in the two symmetrical regions of interest. Differences higher than 10% were considered significant. Cerebral angiography combined with intravascular embolization was carried out after a scitigraphic examination. RESULTS: Based on angiograms, the diameter of the AVM nidus was estimated and varied from 1.0 cm to 9.0 cm. In 13 cases, AVM were visible in the dynamic scintigraphy as areas of increased tracer activity. In each case, SPECT images showed the AVM nidus as a region of decreased tracer accumulation. Hypoperfusion in the brain tissue adjacent to the nidus was seen in 15 subjects. In one patient cerebellar diaschisis was present. The average ratio of activity in the region of AVM to activity in the normally perfused tissue calculated by semiquantitative analysis was 77.5 +/- 10.9%. CONCLUSION: Cerebral perfusion scintigraphy (SPECT images and dynamic scintigraphy) allows one to identify perfusion disturbances caused by the presence of intracranial AVM.