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<p><b>OBJECTIVE</b>To evaluate the femoral head perfusion and to predict the traumatic avascular necrosis (AVN) of the femoral head by single photon emission computerized tomography and computerized tomography (SPECT/CT).</p><p><b>METHODS</b>Totally 18 adult beagle dogs were divided randomly into three equal-sized (n equal to 6) groups. Subsequently different degrees of ischemia model were developed by destroying blood vessels of the femoral head. The left hip received sham operation as normal control and the right hip underwent blood interruption. In Group A, the ligamentum teres was cut off. In Group B, the marrow cavity of the right femoral neck was destroyed while in Group C, the soft tissues at the base of the femoral neck were stripped in addition to the resection of the ligamentum teres and destruction of the marrow cavity. Three hours after surgery, SPECT/CT was performed. Laser Doppler Flowmetry (LDF) measurements were also obtained at three different time points (before operation, immediately and three hours after operation) in order to assess the change process of blood supply to the femoral head.</p><p><b>RESULTS</b>SPECT/CT showed no significant difference in the radionuclide uptake between the right and left femoral heads in Group A (t equal to -0.09, P equal to 0.94) and Group B (t equal to 0.52, P equal to 0.62). However, in Group C, it was 261+/-62 for the right femoral head, only 12% of that in the left femoral head. LDF measurements indicated that the femoral head perfusion was decreased from (45.0+/-3.3) PU to (39.1+/-3.7) PU in Group A,from (44.0+/-2.7) PU to (34.3+/-2.6) PU in Group B, and from (47.3+/-2.1) PU to (4.96+/-0.6) PU in Group C immediately after operation. However, the perfusion was restored and returned to normal values three hours after operation except in Group C.</p><p><b>CONCLUSION</b>SPECT/CT could assess the perfusion of the femoral head semiquantitatively, which might be useful in predicting the development of traumatic AVN.</p>
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Animales , Perros , Cabeza Femoral , Necrosis de la Cabeza Femoral , Tomografía Computarizada de Emisión de Fotón ÚnicoRESUMEN
Objective To investigate the added diagnostic value of SPECT/CT imaging over routine planar whole-body bone scintigraphy (WBBS) for bone metastases from lung cancer. Methods One hundred and forty-six patients with lung cancer, confirmed by pathological examination, underwent routine 99Tcm-MDP (1110 MBq) WBBS, followed by SPECT/CT over the regions with indeterminate findings on WBBS. Both WBBS and bone SPECT/CT images were interpreted by two experienced nuclear medicine physicians in consensus as the positive, negative or uncertain bone metastases. The final diagnosis was comfirmed by pathology or clinical follow-up. x2 test was used to compare the differences between the two imaging methods. Results Finally, 45 patients were diagnosed as positive bone metastases and the other 101 as negative. The diagnostic sensitivity of bone SPECT/CT for bone metastases from lung cancer was 93.3%(42/45), singnificantly higher than that of WBBS (64.4%, 29/45) (x2 = 19.944, P<0.05). The diagnostic accuracy of bone SPECT/CT was 89.7% ( 131/146), much higher than that of WBBS (44.5%,65/146) ( x2 = 69. 598,P < 0.05). The uncertain and incorrect diagnostic rates of bone SPECT/CT and WBBS were 10.3% ( 15/146, raging from 5.3% to 15.2% with 95% confidence interval (CI) ) and 55.5% (81/146, raging from 47. 4% to 63.5% with95% CI), respectively. Conclusion BoneSPECT/CT provides incremental diagnostic value over routine WBBS for bone metastases from lung cancer.
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Objective To evaluate the precision of GFR using Gates method and compared with the results from renal pathological changes. Methods Twenty-seven patients whose 99Tcm-DTPA renograms had no obvious uptake phase were enrolled in Group A, and 27 patients whose 99Tcm-DTPA renograms had obvious uptake phase were enrolled in Group B. The measurement of GFR by Gates method was compared to the creatinine clearance measured and predicted by Cockroft-Gault (C-G), modification of diet in renal disease (MDRD) and SCr level. Renal pathological changes in two groups were compared using Pearson correlation and t test analysis. Results In Group A, GFR determined by Gates method did not show correlation with that estimated by C-G or 1/SCr (r = 0. 357,0. 376, both P >0.05), but was significantly correlated with GFR estimated by MDRD(r = 0. 440, P < 0.05). In Group B, GFR determined by Gates method showed significantly correlation among GFR estimated by MDRD, C-G, and 1/SCr (r =0. 471, 0. 527,0. 452, all P < 0.05). Renal tubulointerstitial damage score in Group A was higher than that in Group B (7.15±2.32, 3.70±3.06, t=4.66, P <0.001). Conclusions GFR determined by Gates method is less precise when 99Tcm-DTPA renogram has no obvious uptake phase than that when 99Tcm-DTPA renogram has obvious uptake phase. Renal tubulointerstitial damage is a strong indicator of no obvious uptake phase in 99Tcm-DTPA renogram.
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Objective To investigate the additional diagnostic value of 99Tcm-MDP SPECT/CT over conventional SPECT scan in patients with spinal bone malignancy. Methods Fifty-two patients (mean age (56±14) years) with suspicious spinal bone diseases underwent both bone SPECT and SPECT/CT imaging right after 99Tcm-MDP whole-body planar bone scintigraphy. All patients were pathologically diagnosed by either spine operation or trans-spinal biopsy. The images were evaluated by two independent reviewers; inter-reviewer agreement was evaluated using a weighted Kappa score. Each focus of abnormality was recorded using a 4-point diagnostic confidence scale: benign (B), possibly benign (PB), possibly malignant (PM) or malignant (M). Results Accord to the pathological results, 36 patients had bone malignancy (19 with metastatic tumors and 17 with non-metastatic tumors) and 16 had benign lesions. Over SPECT images, two reviewers rated 73.1% (38/52) and 67.3% (35/52) the lesions as the equivocal (PB or PM) respectively. Over SPECT/CT images, they rated only 25.0% (13/52) and 13.5% (7/52) lesions as the equivocal. Inter-reviewer agreement was 63.5% (weighted Kappa score=0.62) for SPECT and 78.9% (weighted Kappa score=0.81) for SPECT/CT. Conclusions Compared with99Tcm-MDP SPECT, 99Tcm-MDP SPECT/CT results in a significant reduction of equivocal diagnoses for the spinal bone malignancy.
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Objective To investigate the cerebral blood flow (CBF) perfusion patterns and related factors in hyperthyroidism patients.Methods Twenty-five patients with hyperthyroidism and twenty-two healthy controls matched for age,sex,education were enrolled.~(99)Tc~m-ethylene cysteinate dimer (ECD) SPECT CBF perfusion imaging was performed at rest.Statistical parametric mapping 5.0 software (SPM5) was used and a statistical threshold of P<0.05 (corrected) was applied for signifying changes of regional CBF (rCBF).The semiquantitative values of rCBF were extracted automatically by brain search 1.1 software and were correlated with concentrations of serum thyroid hormones(FT_3,FT_4),thyroid autoimmune antibodies:sensitive thyroid stimulating hormone(sTSH),thyroid peroxidase antibody (TPOAb) and TSH receptor antibody (TRAb) by Pearson analysis,with disease duration by Spearman analysis.Results rCBF was decreased significantly in limbic system and frontal lobe,including parahippocampal gyrus,uncus (posterior entorhinal cortex,posterior parolfactory cortex,parahippocampal cortex,anterior cingulate,right inferior temporal gyrus),left hypothalamus and caudate nucleus (P<0.05,corrected).rCBF in left lingual gyrus,posterior cingulated was negatively correlated with concentration of FT_3(r=-0.468,-0.417,both P<0.05).rCBF in left lingual gyrus,bilateral inferior temporal gyrus,right superior parietal lobe was negatively correlated with concentration of FT_4(r=-0.4M,-0.418,-0.415,-0.459,all P<0.05),while that in left mammillary body and putamen was positively correlated with concentration of FT_4(r=0.419,0.412,both P<0.05).rCBF in left insula was negatively correlated with concentration of sTSH,and right auditory associated cortex was positively correlated with concentration of sTSH(r=-0.504,0.429,both P<0.05).rCBF in left middle temporal gyrus,left angular gyrus was positively correlated with concentration of TRAb while that in right thalamus,right hypothalamus,left anterior nucleus,left ventralis nucleus was negatively correlated with concentration of TRAb(r=0.750,0.862,-0.691,-0.835,-0.713,-0.759,all P<0.05).rCBF in right anterior cingulate,right cuneus,right rectus gyrus,right superior marginal gyrus was positively correlated with concentration of TPOAb(r=0.696,0.581,0.779,0.683,all P<0.05).rCBF in postcentral gyrus,temporal gyrus,left superior marginal gyrus and auditory associated cortex was positively correlated with disease duration(r=0.502,0.457,0.524,0.440,all P<0.05).Conclusion Hypoperfusions in limbic system and fontal lobe were found in hyperthyroidism Patients,which might be associated with thyroid function and disesse duration.