MR breast imaging : a comparative analysis of conventional and parallel imaging acquisition

Assessment of low-cost surgical metallic clip placement for tumor localization in BIRDAS VI breast cancer patients undergoing neoadjuvant chemotherapy

Background

Neoadjunvant chemotherapy has become a challenging connotation for both surgeons and radiologists due to the high clinical response up to dramatic pathological complete response (pCR) that may hinder proper localization of any residual tumoral tissue. So the radiopaque markers implantation at the tumor bed became a reliable and recommended method for tumor localization before surgical intervention or NAC. Many types of commercial clips and markers are available; however they are relatively of high cost and represent a considerable burden on the governments and the heath institute that made the researchers study cheaper alternatives as standard titanium based cholecystectomy surgical clips for tumor localization.

Results

The study was conducted on 45 patients where 57 clips were inserted corresponding to number of lesions found in the total number of the patients. The response to Neoadjunvant chemotherapy was recorded and showed that 6 patients (about 13.3%) had complete radiological response after NAC, while 27 patients (60%) had regressive course after the treatment. The low cost surgical clips were evaluated by using sono-mammography and magnetic resonance imaging, and complications that occurred were recorded. Our study showed that in only 2 patients (3.5%) there was difficulty in clip visualization by Ultrasound during post-treatment follow up. In 45 patients, all the inserted clips (100%) were well visualized as small signal void on MRI at both T1WIs and T2WIs sequences, and the primary malignancy was easily visualized on both MRI and sono-mammography not interfering with the image interpretation and judgment. As regards the reported complications, our results revealed that in only 2 patients (3.5%) there was evidence of positive clip migration, while only 2 patients (3.5%) developed hematoma during the procedure as shown by ultrasound, Also 4 patients (7%) complained of pain only shortly after clip insertion. No other significant complications like infection or heat sensation developed either during the procedure or during MRI. The total price of the surgical clips was calculated with average cost of the needle about 10 US$ equivalent to 170 LE Egyptian pounds and the clip about 1.3 US$ or 20 Egyptian pounds, which is considered of lower cost when compared to the commercial breast markers of different companies with an estimated price range for clip = 75–200 US$ (average 90 US$). So insertion of surgical clips saved about 1135 Egyptian pounds equivalent to 73–75 US$ per clip placement.

Conclusion

We concluded from our study that the use of breast markers are mandatory before NAC where Surgical clips can safely substitute the commercial tissue markers as tumor localizers as they are effective, safe, well tolerated, easily visualized on imaging and do not interfere with assessment of the treatment response, with no evidence of complications and are of low cost compared with the commercial breast clips.

Evaluation of image quality of a 32-channel versus a 12-channel head coil at 1.5T for MR imaging of the brain

BACKGROUND AND PURPOSE

Multichannel phased-array head coils are undergoing exponential escalation of coil element numbers. While previous technical studies have found gains in SNR and spatial resolution with the addition of element coils, it remains to be determined how these gains affect clinical reading. The purpose of this clinical study was to determine if the SNR and spatial resolution characteristics of a 32-channel head coil result in improvements in perceived image quality and lesion evaluation.

MATERIALS AND METHODS

Twenty-one patients underwent MR imaging of the brain at 1.5T sequentially with both a 12-channel and a 32-channel receive-only phased-array head coil. Axial T2WIs, T1WIs, FLAIR images, and DWIs were acquired. Anonymized images were compared side-by-side and by sequence for image quality, lesion evaluation, and artifacts by 3 neuroradiologists. Results of the comparison were analyzed for the preference for a specific head coil.

RESULTS

FLAIR and DWI images acquired with the 32-channel coil showed significant improvement in image quality in several parameters. T2WIs also improved significantly with acquisition by the 32-channel coil, while T1WIs improved in a limited number of parameters. While lesion evaluation also improved with acquisition of images by the 32-channel coil, there was no apparent improvement in diagnostic quality. There was no difference in artifacts between the 2 coils.

CONCLUSIONS

Improvements in SNR and spatial resolution attributed to image acquisition with a 32-channel head coil are paralleled by perceived improvements in image quality.

Breast MR imaging: current indications and advanced imaging techniques

Breast cancer is the most common solid tumor diagnosed in women. In the past decades, great strides have been made in breast cancer screening. While multiple screening trials have shown the benefits of screening mammography, there are limitations to x-ray mammography. Given these inherent limitations, efforts have been made to develop adjunctive imaging techniques, including screening ultrasonography, gamma-specific breast imaging, breast tomosynthesis, dedicated breast computed tomography, and breast magnetic resonance (MR) imaging. This article addresses the current indications and advanced imaging applications of breast MR imaging.