Anna Nocuń

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.

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.

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

ObjectiveThe aim of this study was to investigate the features and patterns of skeletal muscle metastases (SMM) detected with 18F-fluorodeoxyglucose (18F-FDG) PET/computed tomography (PET/CT). Participants and methodsOur database was analyzed for patients with pathologically proven malignancy, who underwent 18F-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. ResultsThe 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. ConclusionSolitary SMM are less common than multiple on 18F-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, 18F-FDG avid intramuscular focus should be suspected to represent metastasis.

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

ObjectiveLarge 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. MethodsWe 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 (99mTc-TOC). A visual analysis of scintigraphic images was done with reference to conventional imaging modalities (computed tomography and bone sicintigraphy). ResultsSRS 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. ConclusionWithin a rather large series of LCNEC, the primary tumor showed an uptake of 99mTc-TOC in all cases, whereas some metastases did show 99mTc-TOC uptake and some others did not.

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

Summary 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.

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.

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

ObjectivePublished 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 99mTc-ethyl cysteinate dimer single photon emission computed tomography. Materials and methodsThe 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. ResultsObliteration 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. ConclusionThe 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.

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.

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.