Mark G O'Callaghan

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PURPOSE Our purpose was to study the association between atherosclerosis measured by arterial calcium on computed tomography (CT) and cerebral atrophy demonstrated by brain magnetic resonance imaging (MRI). MATERIALS AND METHODS IRB approved this prospective study. Twenty-one consecutive patients with acute stroke-like symptoms who are scheduled to have(More)
PURPOSE To retrospectively evaluate the size of the trigeminal nerve on magnetic resonance (MR) images of patients with unilateral trigeminal neuralgia. MATERIALS AND METHODS Institutional review board approval was obtained and informed consent was waived for this HIPAA-compliant study. The sizes of the trigeminal nerves in 31 patients (18 men and 13(More)
Dynamic brain stem compression due to unsuspected Chiari malformation (CM) may mimic a meningeal process and can pose a diagnostic challenge to both the neuroradiologist and the clinician. CM usually goes undetected on the axial CT examination, where severe beam hardening creates difficulty in evaluating the craniocervical junction (Fig 1). In the setting(More)
OBJECTIVE To investigate how gestational age and prior vaginal birth affect cervical anatomy on magnetic resonance imaging during pregnancy. STUDY DESIGN Magnetic resonance images of the cervix were obtained in consecutive patients referred for a suspected fetal abnormality. We used an image processing protocol to measure cervical dimensions, orientation,(More)
Treatment with gamma knife radiosurgery (GKRS) provides adequate short-term pain control in about 70% of the patients with intractable trigeminal neuralgia (TN). The purpose of our study was to evaluate whether the presence of neurovascular contact (NVC) at the root entry zone of the trigeminal nerve on pre-gamma knife MR imaging predicts an increased(More)
Hemodynamic factors may play a role in the seeding and subsequent growth of cerebral metastasis. The authors present a case with 2 foci of cerebral metastasis in the same vascular territory ipsilateral to an occluded internal carotid artery. A 65-year-old man with chronic left frontal lobe infarct and left internal carotid artery occlusion was diagnosed(More)
A case of fetal rhabdomyoma (myxoid type) of the head and neck demonstrated on prenatal magnetic resonance imaging (MRI) is presented. This benign tumor of skeletal muscle is uncommon and should not be confused with its malignant counterpart-rhabdomyosarcoma. With the increasing use of ultrafast MRI, the radiologist is more likely to encounter head and neck(More)
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