Objective To investigate the feasibility of diffusion-weighted imaging (DWI) for differentia-tion of small cell lung cancer (SCLC) and non-small cell lung cancer (NSCLC) at 3.0 T MRI. This study also aims to optimize b values. Methods Thirty-six patients with lung cancer proved by pathology were examined by T2WI and DWI (b = 400, 600 and 800 s/mm2) and apparent diffusion coefficient (ADC) values of each lesion were calculated among different b values. The receiver operating characteristic (ROC) curves were used to calcu-late the difference between the ADC of SCLC and NSCLC and to evaluate the diagnostic capability. Analysis of variance was used to determine difference in ADC of NSCLC histological types at the optimal b values. Results The ADC values of SCLC and NSCLC decreased with increasing b values , and the differences were statistically significant (P = 0.002, P < 0.001). ROC analysis showed that the area under curve (AUC) values were 0.775、0.892、0.804 (b = 400, 600, 800 s/mm2, respectively). The AUC with a b value of 600 s/mm2 was the largest. When an ADC of 1.296 × 10-3 mm2/s was considered as a threshold, the sensitivity, and specificity were 76.9%, and 90.0%, respectively. Conclusion DWI reflects the diffusion motion of water protons in lung carcinoma and it has moderate diagnosis potency in differentiating SCLC and NSCLC. The optimal b value is 600 s/mm 2.

Objective To investigate the value of spiral CT in therapy observation during and after radiofrequency ablation (RFA) for lung or liver tumors. Methods Spiral CT-guided RFA were performed in 35 patients (38 lesions) with lung or liver tumors. CT value of lesions during operation and the changes of lesions after operation were observed. Results Thirty-eight lesions were accurately located under spiral CT. The position of the electrode and the expension of claw-like thin needle electrode could be observed directly. CT value of lesions decreased and some gasification foci in some lesions were observed after RAF therapy. One month after RFA, tumor volume decreased, and the tumors present as slightly low-density mass on contrast-enhanced CT. The total effective rate of RFA was 85.71% (30/35). Conclusion Spiral CT is able to accurately guide RFA treatment for lung or liver tumors and evaluate the efficacy of therapy.

Objective To explore the feasibility of diffusion-weighted imaging (DWI) in assessing the efficacy of chemoradiotherapy for cervical cancer.Methods Data of magnetic resonance imaging (MRI) and DWI were analyzed in 32 patients with uterine cervical cancer received conventional prior to chemoradiotherapy and after 1 and 3 months of therapy.13 cases of normal controls also had been examed by MRI and DWL DWI with b values of (0,300) s/mm2 and b values of (0,600) s/mm2 were performed in all patients.Pretreatment post-treatmentADC values were compared between the health group and patients group.Results When the b =300 s/mm2,normal cervical average ADC value was (1.72±0.31)×10-3 mm2/s,cervical cancer was (1.10±0.24)×10-3 mm2/s before treatment and was (1.61±0.23)×10-3 mm2/s after treatment.When the b =600 s/mm2,normal cervical average ADC value was (1.46±0.25)×10-3 mm2/s cervical cancer was (0.89±0.21)×10-3 mm2/s before treatment and was (1.54±0.18)×10-3 mm2/s after treatment.When b =300 s/mm2,ADC value was higher than when b =600 s/mm2.ADC values of cervical cancer was significantly lower than that of the normal cervix group,ADC values of cervical lesions after chemoradiotherapy was significantly higher than that before chemoradiotherapy (P ＜ 0.05).In the same group with different b values,ADC value was not significant (P ＞ 0.05).Conclusion Joint observation of DWI and ADC values could be more objective and accurate in the analysis of the disease and would help to evaluate the efficacy of chemoradiotherapy.

Adolescent ; Adult ; Aged ; Aged, 80 and over ; Female ; Fluorodeoxyglucose F18 ; Follow-Up Studies ; Humans ; Lymph Nodes ; diagnostic imaging ; pathology ; Lymphoma, Large B-Cell, Diffuse ; diagnostic imaging ; pathology ; Male ; Middle Aged ; Neck ; diagnostic imaging ; pathology ; Positron-Emission Tomography ; Prognosis ; Young Adult

OBJECTIVETo compare the diagnostic value of ¹⁸F-fluorodeoxyglucose-positron emission tomography/computed tomography (¹⁸F-FDG PET/CT) and large-scale diffusion weighted imaging (DWI) for evaluation of non-Hodgkin lymphoma (NHL) bone marrow (BM) infiltration.

METHODSA total of 79 patients with pathologically diagnosed NHL underwent ¹⁸F-FDG PET/CT, large scale DWI and BM pathological examination. BM examination as the "gold standard", the performance (the sensitivity, specificity, accuracy, positive and negative predictive value) of ¹⁸F-FDG PET/CT and large scale DWI for evaluation of BM infiltration was compared and the risk of BM infiltration of different subtypes and sources of NHL was analyzed.

RESULTS25 of 79 cases were diagnosed as BM infiltration by pathological examination with 57 BM sites. Abnormal high BM metabolisms were identified in 22 cases with 56 BM sites by ¹⁸F-FDG PET/CT and 25 cases with 58 BM sites by large-scale DWI. The sensitivity, specificity, accuracy, positive and negative predictive value of ¹⁸F-FDG PET/CT were 80.0%, 96.3%, 91.1%, 90.9%, 91.2%, respectively. And they were 84.0%, 92.6%, 89.9%, 84.0%, and 92.6% by large-scale DWI, respectively. A receiver operating characteristic (ROC) analysis demonstrated that there was no statistical difference in ¹⁸F-FDG PET/CT and large-scale DWI (P>0.05). The area under ROC curve for ¹⁸F-FDG PET/CT and large-scale DWI were 0.911 and 0.883 respectively. The incidences of BM infiltration in aggressive NHL patients by ¹⁸F-FDG PET/CT (21/69, 30.4%) and large-scale DWI (23/69, 33.3%) were higher than those (PET/CT: 10.0%; large-scale DWI: 20.0%; P>0.05) in indolent NHL patients.

CONCLUSION¹⁸F-FDG PET/CT and large-scale DWI had important clinical value in diagnosing BM infiltration of NHL. A combination of ¹⁸F-FDG PET/CT, large-scale DWI and pathological examination could improve the positive rate of BM infiltration in NHL.

Adolescent ; Adult ; Aged ; Aged, 80 and over ; Bone Marrow ; pathology ; Female ; Fluorodeoxyglucose F18 ; Humans ; Lymphoma, Non-Hodgkin ; diagnosis ; diagnostic imaging ; pathology ; Male ; Middle Aged ; Positron-Emission Tomography ; Sensitivity and Specificity ; Tomography, X-Ray Computed ; Young Adult