Prospective navigator-echo-based real-time triggering of fetal head movement for the reduction of artifacts.

The purpose of this study was to evaluate the neuroimaging quality and accuracy of prospective real-time navigator-echo acquisition correction versus untriggered intrauterine magnetic resonance imaging (MRI) techniques. Twenty women in whom fetal motion artifacts compromised the neuroimaging quality of fetal MRI taken during the 28.7 +/- 4 week of pregnancy below diagnostic levels were additionally investigated using a navigator-triggered half-Fourier acquired single-shot turbo-spin echo (HASTE) sequence. Imaging quality was evaluated by two blinded readers applying a rating scale from 1 (not diagnostic) to 5 (excellent). Diagnostic criteria included depiction of the germinal matrix, grey and white matter, CSF, brain stem and cerebellum. Signal-difference-to-noise ratios (SDNRs) in the white matter and germinal zone were quantitatively evaluated. Imaging quality improved in 18/20 patients using the navigator echo technique (2.4 +/- 0.58 vs. 3.65 +/- 0.73 SD, p < 0.01 for all evaluation criteria). In 2/20 patients fetal movement severely impaired image quality in conventional and navigated HASTE. Navigator-echo imaging revealed additional structural brain abnormalities and confirmed diagnosis in 8/20 patients. The accuracy improved from 50% to 90%. Average SDNR increased from 0.7 +/- 7.27 to 19.83 +/- 15.71 (p < 0.01). Navigator-echo-based real-time triggering of fetal head movement is a reliable technique that can deliver diagnostic fetal MR image quality despite vigorous fetal movement.

Posterior sacculation of the uterus in a patient presenting with flank pain at 29 weeks of gestation.

BACKGROUND: Uterine sacculation is a rare complication of pregnancy and may cause substantial peripartal morbidity. CASE: A possible diagnosis of posterior uterine sacculation was raised when a 34-year-old Gravida 1 Para 1 presented with bilateral flank pain at 29 weeks. Sonographic and magnetic resonance imaging findings confirmed the diagnosis and demonstrated bilateral dilated renal pelvises. Bilateral nephrostomas were placed, offering the patient considerable relief. A healthy female newborn was delivered by cesarean at 34 1/7 weeks. Operative findings confirmed the posterior sacculation of the uterus. CONCLUSION: Early diagnosis of sacculation of the uterus is necessary to limit maternal and fetal morbidity and mortality. For a detailed evaluation of the pelvic anatomy, we recommend the use of magnetic resonance imaging in the third trimester.

Photodynamic detection of diseased axillary sentinel lymph node after oral application of aminolevulinic acid in patients with breast cancer.

Benign as well as malignant tumour tissues of the breast demonstrate higher fluorescence intensity (FI) than normal breast tissue after application of a photosensitiser. As a follow-up study, we evaluated the FI of metastatic sentinel lymph nodes and metastatic axillary lymph nodes compared to nonmetastatic sentinel and axillary lymph nodes in patients with breast cancer. In all, 11 patients received 30 mg 5-aminolevulinic acid (ALA) kg(-1) bodyweight orally 3 h prior to surgery. The sentinel lymph node was marked with Nanocoll preoperatively and with a blue dye intraoperatively. Tumour excision, excision of the sentinel lymph node and an axillary lymph node dissection were performed during the same surgical session. The operation site was illuminated with blue light (400 nm) to obtain macroscopic tissue characterisation of fluorescence. Tissue samples were stored protected from light, and analysed using a fluorescence microscope. Results were correlated with histopathology. In all, 14 sentinel lymph nodes, seven axillary lymph nodes and seven primary tumours were analysed. Metastatic sentinel lymph nodes demonstrated a statistically significant higher FI than nonmetastatic sentinel lymph nodes (2630 vs 526, P<0.0001). The FI of metastatic sentinel lymph nodes, of metastatic axillary lymph nodes and of the primary tumour were comparably high, and were statistically significantly higher compared to the normal mammary tissue. Intraoperatively, only in a few cases, it was possible to recognise the metastatic sentinel lymph node macroscopically with blue light. Our study indicates that photodynamic diagnosis with ALA has a potential in the diagnosis and detection of the sentinel lymph node in patients with breast cancer, and is worth to be further investigated and developed for intraoperative photodynamic diagnosis and possibly therapy.

Primary breast lymphoma, contralateral breast cancer, and bilateral Brenner tumors of the ovary.

BACKGROUND: Primary lymphoma of the breast is an unusual clinical entity. Its presence with invasive breast cancer and bilateral Brenner tumors of the ovary is very rare. CASE: We report a 62-year-old woman referred for further evaluation of a palpable mass in her breast. She was diagnosed and treated for simultaneous primary lymphoma of the right breast, contralateral invasive ductal carcinoma, and bilateral Brenner tumors of the ovary. One year after treatment, she is free of recurrence or progression. CONCLUSION: Compared with breast carcinoma, primary breast lymphoma is a rare disease but should be considered in the differential diagnosis of breast masses. The presence of both breast malignancies presents a challenge in treatment decisions.

Staging endometrial cancer: role of magnetic resonance imaging.

This review article summarizes and comments the role of magnetic resonance imaging (MRI) in the management of endometrial cancer. The MRI technique, appearance, and diagnostic criteria of endometrial carcinoma are discussed. The value of MRI in the preoperative staging of endometrial cancer is compared to alternative strategies. Contrast-enhanced MRI performs best in the pretreatment evaluation of myometrial or cervical invasion, compared to ultrasonography (US), computed tomography (CT), or nonenhanced MRI. The overall costs and accuracy are similar to those of the current methods of staging, including intraoperative gross dissection of the uterus. In addition, results of MRI might decrease the number of unnecessary lymph node dissections. J. Magn. Reson. Imaging 2001;13:850-855.

Carpal tunnel syndrome: assessment by turbo spin echo, spin echo, and magnetization transfer imaging applied in a low-field MR system.

PURPOSE: The purpose of this work was to evaluate patients with carpal tunnel syndrome (CTS) using a low-field extremity MR system (E-MRI: 0.2 T). METHOD: Twenty-two patients with typical findings of CTS and 30 control persons were imaged on an E-MRI. Axial T2-weighted turbo SE (TSE), T1-weighted SE sequences, and 2D GRE magnetization transfer (MTC) sequences were compared. SE and MTC sequences were obtained before and after contrast agent administration (0.1 mmol/kg body wt of Gd-DTPA). Two readers evaluated typical MR findings of CTS independently. RESULTS: Patients with CTS demonstrated palmar bowing of the flexor retinaculum significantly more often. The normal or edematous median nerve was best identified on TSE and MTC scans (kappa = 0.59 and 0.8). The MTC sequences showed perineural enhancement significantly better than respective T1-weighted SE sequences but were rated second in comparison with T2-weighted TSE scans. CONCLUSION: At low-field strength, median nerve edema is best depicted on T2-weighted TSE sequences, whereas MTC sequences are most sensitive to perineural contrast enhancement.

MR imaging of the breast in patients with positive margins after lumpectomy: influence of the time interval between lumpectomy and MR imaging.

OBJECTIVE: Postsurgical contrast enhancement resulting from inflammatory changes at the site of surgery limits the accuracy of MR imaging of the breast in diagnosing residual breast cancer. This study was undertaken to evaluate the influence of the time interval between lumpectomy and MR imaging on the diagnosis of residual breast cancer. MATERIALS AND METHODS: Sixty-eight patients who had undergone excisional biopsy with positive resection margins underwent MR imaging for evaluation of residual breast cancer and possible breast conservation. Patients were retrospectively stratified according to the time interval between lumpectomy and MR imaging. Dynamic and morphologic enhancement features were used for lesion characterization. Imaging findings were correlated with results of histopathology. Sensitivity, specificity, positive predictive value, and negative predictive value were calculated for patients waiting 7, 14, 21, 28, 35, and 42 days after initial surgery before undergoing MR imaging of the breast. RESULTS: The time interval between lumpectomy and MR imaging of the breast had the greatest influence on the specificity and negative predictive value of MR imaging, increasing progressively over time. A plateau of highest values of 75% specificity and 86% negative predictive value was reached at 28 and 35 days after surgery, respectively. Although the sensitivity and positive predictive value showed smaller variations over time, peak values of 95% sensitivity and 92% positive predictive value were obtained at 35 and 28 days after surgery, respectively. CONCLUSION: We recommend scheduling patients with positive resection margins no earlier than 28 days after initial surgery for evaluation of residual cancer using MR imaging of the breast.

Prediction of deep myometrial invasion in patients with endometrial cancer: clinical utility of contrast-enhanced MR imaging-a meta-analysis and Bayesian analysis.

PURPOSE: To determine if, in a patient with an endometrial cancer, in addition to the knowledge of tumor grade, preoperative magnetic resonance (MR) imaging findings contribute to treatment stratification and specialist referral. MATERIALS AND METHODS: By using a MEDLINE literature search and institutional pathology reports, pretest probabilities for myometrial invasion were correlated with tumor grade. Likelihood ratios (LRs) were obtained through summary receiver operating characteristics. RESULTS: The mean pretest probabilities of deep myometrial invasion were derived from seven articles (1,875 patients) and from 125 institutional pathology reports. LRs for the prediction of myometrial invasion with contrast-enhanced MR imaging were derived from nine studies (742 patients); positive and negative LRs were 10.11 and 0.1, respectively. The mean weighted pretest probabilities of deep myometrial invasion in patients with tumor grades 1, 2, or 3 were 13%, 35%, or 54%, respectively. Posttest probabilities of deep myometrial invasion for grades 1, 2, or 3 increased to 60%, 84%, or 92%, respectively, for positive and decreased to 1%, 5%, or 10%, respectively, for negative MR imaging findings. CONCLUSION: Use of contrast-enhanced MR imaging significantly affects the posttest probability of deep myometrial invasion in patients with all grades of endometrial cancer and could be used to select patients for specialist referral.