Differential diagnosis between a granuloma and radicular cyst: effectiveness of magnetic resonance imaging.

AIM: To investigate the diagnostic reliability and accuracy of magnetic resonance imaging (MRI) to differentiate periapical lesions of endodontic origin and to compare the results with histopathological information. METHODOLOGY: The radiolucent periapical jaw lesions of 34 patients, which were surgically enucleated, were investigated by two radiologists using MRI, based on the same six criteria, to categorize the lesions as granulomas, radicular cysts or others. After apicoectomies, two oral pathologists (blinded to the radiologist's diagnoses) analysed all specimens by referring to seven specific parameters and diagnosed the specimens as granulomas, radicular cysts or other conditions. The inter-rater agreements between the radiologists and pathologists in terms of MRI and histological diagnoses, respectively, along with the discriminant power of the adopted criteria and the accuracy of the MRI assessments compared with the histopathological results, were calculated. Cohen's kappa test was adopted to examine inter-rater agreement between the two radiologists and two pathologists. Guttman's lambda coefficient (λ6 ) was used to evaluate the internal consistency of the items used for the differential diagnosis by radiologists. The accuracy resulted from a receiver operator characteristic (ROC) analysis. RESULTS: A strong inter-rater reliability was observed between the two radiologists (k-statistic = 0.86, P = 0.0001) and the two pathologists (k-statistic = 0.88, P = 0.0001). The internal consistency of the diagnostic items was 0.605 for cysts and 0.771 for granulomas. The accuracy (true positives plus true negatives) of the radiologists was greater than that of the pathologists based on analysis (area under the curve = 0.87 and 0.91, respectively). CONCLUSIONS: The reliability and accuracy of MRI were high and comparable to histopathological reliability, highlighting the usefulness of this noninvasive technique as a pre-treatment diagnostic method for periapical endodontic lesions.

Localizer sequences of magnetic resonance imaging accurately identify osteoporotic vertebral fractures.

The aim of the present study was to evaluate the performance of sagittal MR localizer (MR-loc), in terms of diagnostic accuracy and intra- and inter-observer agreement in the detection of vertebral fractures (VFs). Three-hundred MR examinations of the thoracic and/or lumbar spine were randomly collected. A semi-quantitative approach was used and morphometric analysis was performed when a VF was suspected. MR-loc images were evaluated blindly by three radiologists in two different sessions. A full diagnostic sagittal T1-weighted fast spin echo MR sequence was used as standard of reference (RS). Degenerative arthritis was also scored on RS. Only vertebral bodies which were assessable by both MR-loc and RS were considered for the analysis. Area under the receiver operating characteristic curve (AUROC), Cohen kappa statistic, and linear-by-linear association were used for statistical analysis. Kappa values were compared by means of the z distribution. A total of 2186 vertebrae were analysed in 300 MRI exams (147 males, 153 females, 59.4±16.4y.o.). Sixty-seven out of 2136 (3.1%) VFs were identified in 23/300 (7.7%) patients submitted to MRI. In the detection of VFs, sensitivity and specificity of MR-loc were both 100% (accuracy AUROC=1.000). Inter-observer agreement was excellent (k=0.938±0.013), while intra-observer agreement was perfect (k=1.000). The diagnostic performance was independent from degenerative arthritis, vertebral level, type and grade of VFs. MR-loc is a simple but accurate tool in the detection of VFs. It should be introduced for systematic evaluation in the detection of VFs in MR examinations performed in daily clinical practice.

Contrast enhanced MRI and ¹8F-FDG PET-CT in the assessment of multiple myeloma: a comparison of results in different phases of the disease.

OBJECTIVES: The aim of our study was to compare the accuracy of contrast enhanced MRI and FDG PET-CT in the staging, treatment evaluation and follow-up of multiple myeloma. METHODS: We retrospectively reviewed 210 PET-CT and 210 MRI studies of patients affected by multiple myeloma. MRI was always performed within 15 days of PET-CT. All the images have been evaluated by two expert oncologic radiologists. RESULTS: Patient population included 81 females and 110 males (age 61.9 ± 9.9 years-old). Sixty-two patients have been evaluated at diagnosis, 58 at the end of therapies and 90 during follow-up. In 12/62 patients (19.4%) at diagnosis, differences between MRI and PET-CT findings determined changes in the staging: PET-CT was responsible for 11 down-staging (17.7%) and MRI only for one (1.6%). In 27/40 patients (67.5%) with good or complete clinical response to therapies the normalization of findings was faster for PET-CT than MRI. Ten out of 90 patients (10/90 - 11.1%) in follow-up protocol presented clinical recurrence of the disease: MRI detected active lesions in 8 of them (80.0%) and PET-CT in 5 patients (50.0%, all detected by MRI too). CONCLUSIONS: MRI achieved better results than PET-CT in the staging and in patients with multiple myeloma recurrence. PET-CT, showed prompt change of imaging findings, faster than MRI, in patients with positive response to therapy.

Preoperative local staging of endometrial cancer: transvaginal sonography vs. magnetic resonance imaging.

OBJECTIVES: To compare the accuracy of transvaginal sonography (TVS) and magnetic resonance imaging (MRI) in the preoperative staging of endometrial carcinoma. METHODS: This was a prospective study in which 74 women consecutively diagnosed with endometrial carcinoma were examined using TVS by physicians trained in gynecological sonography and MRI by radiologists with a special interest in gynecology. All patients underwent surgical-pathological staging after removal of the uterus, adnexa and pelvic lymph nodes. Sensitivity, specificity, and positive and negative predictive values were calculated for each imaging modality with regard to detection of neoplastic invasion of the outer half of the myometrium and cervical involvement. RESULTS: TVS and MRI performed equally well in the preoperative staging of endometrial cancer, with no statistically significant differences between the two techniques. The sensitivity, specificity, positive and negative predictive values, and overall diagnostic accuracy for TVS in the evaluation of myometrial infiltration were 84%, 83%, 79%, 88% and 84%, respectively. Respective values for MRI were 84%, 81%, 77%, 87% and 82%. The corresponding statistics for detection of cervical involvement were 93%, 92%, 72%, 98% and 92% for TVS; and 79%, 87%, 58%, 95% and 85% for MRI. CONCLUSIONS: When carried out by expert practitioners, TVS shows good accuracy in the local staging of endometrial carcinoma. Because of its high costs, MRI should be offered only to those in whom TVS produces images of poor quality.

11C-choline positron emission tomography/computerized tomography for tumor localization of primary prostate cancer in comparison with 12-core biopsy.

PURPOSE: (11)C-choline positron emission tomography is an innovative imaging technique for prostate cancer. We assessed the sensitivity of positron emission tomography used together with computerized tomography for intraprostatic localization of primary prostate cancer on a nodule-by-nodule basis, and compared its performance with 12-core transrectal biopsy. MATERIALS AND METHODS: In 43 patients with known prostate cancer who had received positron emission tomography/computerized tomography before initial biopsy, we assessed sensitivity of positron emission tomography/computerized tomography for localization of nodules 5 mm or greater (those theoretically large enough for visualization) using radical prostatectomy histopathology as the reference standard. Comparison with transrectal ultrasound guided biopsy was based on sextant assessment of all cancer foci following sextant-by-sextant matching and reconstruction. Sensitivity/specificity of positron emission tomography/computerized tomography and magnetic resonance imaging for prediction of extraprostatic extension was also assessed. RESULTS: Positron emission tomography/computerized tomography showed 83% sensitivity for localization of nodules 5 mm or greater. At logistic regression analysis only nodule size appeared to influence sensitivity. At sextant assessment positron emission tomography/computerized tomography had slightly better sensitivity than transrectal ultrasound guided biopsy (66% vs 61%, p = 0.434) but was less specific (84% vs 97%, p = 0.008). For assessment of extraprostatic extension, sensitivity of PET/CT was low in comparison with magnetic resonance imaging (22% vs 63%, p <0.001). CONCLUSIONS: Positron emission tomography/computerized tomography has good sensitivity for intraprostatic localization of primary prostate cancer nodules 5 mm or greater. Positron emission tomography/computerized tomography and transrectal ultrasound guided biopsy show similar sensitivity for localization of any cancer focus. Positron emission tomography/computerized tomography does not seem to have any role in extraprostatic extension detection. Studies of diagnostic accuracy (as opposed to tumor localization) are needed in patients with suspected prostate cancer to see whether positron emission tomography/computerized tomography could have a role in not selected patients.

Ultrasonography detection of early bone erosions in the metacarpophalangeal joints of patients with rheumatoid arthritis.

OBJECTIVE: To compare ultrasonography (US) and magnetic resonance imaging (MRI) in their capability to detect bone erosions in early-advanced rheumatoid arthritis, where no erosion was evident on conventional radiography (X-ray). METHODS: Metacarpophalangeal (MCP), radiocarpal and ulnocarpal joints of 13 patients with rheumatoid arthritis, with bone erosion that was not detected by conventional X-ray, were examined by US and MRI. Ten controls underwent examination of the same joints by US. RESULTS: None of the controls showed bone erosions at US examination. No significant difference between US and MRI in detecting bone erosion was observed in wrist joints, whereas a significantly higher number of erosions was detected by US in MCP joints. CONCLUSION: US is at least as sensitive as MRI in detecting bone erosions in MCP and wrist joints. Since US examination is a more easily available and less expensive procedure than MRI, our findings justify its use as a diagnostic tool for early arthritis. In addition US may also be utilized in the follow up of patients with an established diagnosis of inflammatory arthritis.

Role of color Doppler ultrasonography in the preoperative staging of pancreatic cancer.

We describe our experience with color Doppler ultrasonography (CDU) in the preoperative staging of pancreatic cancer and, particularly, in detecting the involvement of the portal-mesenteric trunk (PMT). Of the 54 patients studied, 43 (79.6%) underwent surgery and 11 (20.4%) did not because of evident infiltration of the PMT. Of the 43 patients operated on, the CDU study was normal in 8 cases (18.6%), abnormal in 33 (76.7%), and not possible in the remaining 2 cases (4.7%). Results of the CDU were confirmed intraoperatively in 39 cases (diagnostic accuracy, 95.1%). In only two cases (4.9%) did the CDU not show involvement of the PMT, which was, instead, demonstrated by intraoperative ultrasonography (false negatives). Of the 11 nonoperated patients, all showed morphological alterations at CDU, while only 7 showed hematic flow changes. The sensitivity of CDU was 94.2% and the specificity 100%. The positive predictive value was 100%; the negative predictive value, 75%. The results indicate that CDU may be the first imaging technique for preoperative assessment of PMT involvement in pancreatic cancer.

[Transrectal ultrasonography in the study of recurrences in patients surgically treated for rectal neoplasms]. / Studio mediante ecografia transrettale delle recidive nei pazienti operati per neoplasia rettale.

The value of transrectal US is known in the preoperative staging of rectal cancer but remains debated in the follow-up of the patients submitted to anterior resection or local therapy. The authors report their experience with the postoperative follow-up of 80 patients submitted to 125 transrectal US exams to study method reliability. The results were 9 true positive, 2 false positive, 113 true negative and 1 false negative cases, with 90% sensitivity, 98.3% specificity and 97.6% accuracy rates. Positive predictive value was 81.8% and negative predictive values was 99.1%. Twelve patients were submitted also to MRI which correctly diagnosed one false negative result of transrectal US. Twenty-one patients were examined also with transrectal Doppler and color-Doppler US: in rectal cancer recurrences the peak velocity of hemorrhoid vascular flow was higher than in non-recurrent patients. On the basis of our results, transrectal US deserves to be included in the postoperative follow-up of the patients submitted to anterior resection or to local therapy for rectal cancer. Moreover, according to our preliminary findings, Doppler and color-Doppler US can improve transrectal US reliability in detecting local recurrences.