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.

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.

[Lymphoscintigraphy in oncology--the role in the preoperative diagnosis]. / Limfoscyntygrafia w onkologii--znaczenie w diagnostyce przedoperacyjnej.

Lymphoscintigraphy is the nuclear medicine procedure, which visualize the distribution of radiolabelled particles in the lymph vessels and lymph nodes. The sentinel node concept presumes that the first lymph node to receive drainage from a tumour will show the metastasis if there has been lymphatic tumour spread. Detection of metastatic involvement of lymph nodes is essential for management and prognostic evaluation in cancer patients. Sentinel lymph node biopsy, radioguided intraoperative lymph node detection widely increased the role of lymphatic mapping in oncology. This article provides a brief history of the sentinel lymph node concept, discusses radiopharmaceuticals, equipment and techniques in lymphatic mapping mainly in melanoma and breast cancer.

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.

[Thyrotropin receptor antibodies (TRAb) as a test of surgical treatment effectiveness in Graves-Basedow's diseases]. / Przeciwciala przeciw receptorom TSH jako test skutecznosci leczenia operacyjnego w chorobie Gravesa-Basedowa.

The aim of the study was to assess the relations between the concentration of antibodies against TSH receptors (TRAb) and the outcome of the surgical treatment in Graves-Basedow's disease. The studies were performed in 30 patients (age range--18-50, mean -37) operated on for Graves-Basedow's disease and in 20 healthy controls. In control group, the TRAb concentration was mean -2.75 +/- 2.06 U/l, the TSH mean -1.06 +/- 0.53 mlU/l, and FT4 mean -14.71 +/- 2.15 pmol/l. The thyroid volume was mean -14.45 +/- 2.37 ml. In the group operated on antibody concentration was determined before and 12 months after the surgery. The TSH and FT4 concentrations were also determined before and 12 months after the operation. Moreover, the size of the thyroid remnant was assessed ultrasonographically 12 months after the procedure. The results showed the effectiveness of the surgical treatment, i.e. hyperthyroidism was not observed in 22 out of 30 patients. Among these 22 patients, euthyreosis was found in 14 cases (46%) and hypothyreosis was observed in 8 cases (27%). In the euthyreosis group, the pre-operative TRAb concentration was mean -24.00 +/- 11.04 U/l. 12 months after the operation, the decreased levels of antibodies were found in 13 patients (mean -6.14 +/- 5.71 U/l). In the hypothyreosis group, the pre-operative TRAb concentration was mean -24.50 +/- 10.43 U/l. After the surgical procedure, TRAb levels were normal in all patients, the average values being 2.13 +/- 1.34 U/l. In 8 patients with recurrent hyperthyroidism (27%), TRAb concentration before the surgery was higher, mean -107.25 +/- 56.69 U/l. 12 months after subtotal strumectomy, the patients in this group still did not show normal TRAb levels (mean -54.25 +/- 51.61 U/l). Moreover, the relations between the size of the thyroid remnant and the TRAb level were evaluated. In the group with recurrent hyperthyroidism and high TRAb levels, the thyroid size (volume) left was mean -12.10 +/- 6.25 ml, in the euthyreosis group mean -5.54 +/- 2.23 ml, while in the hypothyreosis group it was mean -4.86 +/- 1.14 ml.