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Mark C DeLano

Publications and source records attributed to Mark C DeLano.

5 recordsLinked to original sources

Lumbar spine MRI in the elite-level female gymnast with low back pain.

OBJECTIVE: Previous studies have shown increased degenerative disk changes and spine injuries in the competitive female gymnast. However, it has also been shown that many of these findings are found in asymptomatic athletic people of the same age. Previous magnetic resonance imaging (MRI) studies evaluating the gymnastic spine have not made a distinction between symptomatic and asymptomatic athletes. Our hypothesis is that MRI will demonstrate the same types of abnormalities in both the symptomatic and asymptomatic gymnasts. DESIGN: Olympic-level female gymnasts received prospectively an MRI exam of the lumbar spine. Each of the gymnasts underwent a physical exam by a sports medicine physician just prior to the MRI for documentation of low back pain. Each MRI exam was evaluated for anterior apophyseal ring avulsion injury, compression deformity of the vertebral body, spondylolysis, spondylolisthesis, degenerative disease, focal disk protrusion/extrusion, muscle strain, epidural mass, and bone-marrow edema. PATIENTS: Nineteen Olympic-level female gymnasts (age 12-20 years) were evaluated prospectively in this study. All of these gymnasts were evaluated while attending a specific training camp. RESULTS: Anterior ring apophyseal injuries (9/19) and degenerative disk disease (12/19) were common. Spondylolysis (3/19) and spondylolisthesis (3/19) were found. Focal bone-marrow edema was found in both L3 pedicles in one gymnast. History and physical exam revealed four gymnasts with current low back pain at the time of imaging. There were findings confined to those athletes with current low back pain: spondylolisthesis, spondylolysis, bilateral pedicle bone-marrow edema, and muscle strain. CONCLUSIONS: Our initial hypothesis was not confirmed, in that there were findings that were confined to the symptomatic group of elite-level female gymnasts.

Adolescent↗

3T MR imaging of the brain.

The advent of very high field clinical scanners that operate at 3T is taking structural and functional imaging to new levels and is reinvigorating clinical spectroscopy, fMR imaging, and noncontrast-enhanced methods of MRA. Most of the challenges that are related to 3T imaging have been addressed to facilitate routine clinical imaging. An awareness of the complexities that underlie the solutions to these challenges is important to the continued improvements to the 3T platform so that its maximal potential can be reached. The development of the multichannel-head coils and the improvement in the design of body coils, concurrently with the development of multichannel capabilities that enable parallel imaging, have benefited all field platforms. Perhaps the added value of parallel imaging has been greatest at 3T where the additional signal can be exploited. The definition of very high field is a moving target, and may be well on its way to 7.0 T, although in terms of the current clinical state of the art, 3T is our current reference.

Artifacts↗

3.0 T versus 1.5 T MR angiography of the head and neck.

This article presents the advantages and challenges of MR angiography of the intracranial and extracranial cerebral vasculature at 3.0 T with comparative assessment to 1.5 T approaches. The physical basis for the superiority of 3.0 T MR angiography is discussed in the context of evolving technological capabilities afforded by the synergistic advent of higher field scanners, improved coil design, and parallel imaging. This review emphasizes 3.0 T issues related to noncontrast three-dimensional time of flight MR angiography of the intracranial circulation, contrast enhanced three-dimensional time of flight MR angiography of the extracranial cerebral vasculature, and carotid plaque characterization.

Artifacts↗

Asymmetry of subinsular anisotropy by in vivo diffusion tensor imaging.

The cortical regions specialized in speech-language exhibit a left-right asymmetry, e.g., a larger cortical size in the left auditory cortex and Wernicke's area. The possibility of developmental asymmetry in axonal fibers interconnecting speech-language cortical areas can be investigated by in vivo diffusion tensor imaging. Fifteen right-handed native English speakers showed a markedly significant asymmetry (P < 0. 0005) in the relative anisotropy of water diffusion in the subinsular white matter, greater on the left. Additionally, the first principal diffusivity was greater and the second and third principal diffusivities were smaller on the left than right side. These results suggest the subinsular axonal structures developed differently between the left and right sides. A possible association between the hemispheric specialization in language and speech and the subinsular axonal fiber development is discussed.

Adult↗

High b-value diffusion imaging.

Perhaps one of the greatest benefits of the development of high b-value technology has been the insight provided into the physiologic basis of diffusion imaging. The multiexponential features of the diffusion process are revealed on scans obtained with high b-value. The subsequent isotropic diffusion images have the distinct advantage of more accurately reflecting the intrinsic ADC of the tissues examined. This feature has the potential to facilitate clinical diagnosis. The degree to which this is proved to be clinically relevant is dependent on future investigation, but initial results are promising. The clinical potential of high b-value imaging at higher field strength remains to be explored. The greater signal to noise afforded by the use of 3-T scanners will likely make higher b-value imaging more practical with less costly scan time penalties necessary at lower field strengths.

Blood-Brain Barrier↗