Incomplete Cord Syndromes: Clinical and Imaging Review.

The ability to localize the three spinal tracts (corticospinal tract, spinothalamic tract, and dorsal [posterior] columns) involved in incomplete spinal cord syndromes at cross-sectional imaging and knowledge of the classic clinical manifestations of the various syndromes enable optimized imaging evaluation and provide clinicians with information that aids in diagnosis and treatment. The requisite knowledge for localizing these tracts is outlined. The authors review the spinal cord anatomy, blood supply, and course of these tracts and describe the various associated syndromes: specifically, dorsal cord, ventral cord, central cord, Brown-Séquard, conus medullaris, and cauda equina syndromes.

Multimodality Imaging Spectrum of the Extranodal Lymphomas in the Head and Neck-A Pictorial Review.

Lymphoma is the second most common malignant neoplasm of the head and neck region, involving the nodal and/or extranodal sites or both in a variable fashion. Lymphoma may mimic a variety of tumors in this region depending on the subsite involved. The usual presentation of lymphomatous disease is presence of multiple enlarged, often conglomerate, lymph nodes without significant necrosis.

Imaging of Intracranial and Orbital Complications of Sinusitis and Atypical Sinus Infection: What the Radiologist Needs to Know.

Sinusitis is a common disease. Complications, however, are less common and can be life threatening. Major complications occur from extension of disease into the orbit and intracranial compartment and often require emergent treatment with intravenous (IV) antibiotics or operative intervention.

The Many Faces of Granulomatosis With Polyangiitis: A Review of the Head and Neck Imaging Manifestations.

Objective: Wegener granulomatosis has recently been renamed as granulomatosis with polyangiitis (GPA). In this review, we examine the clinical criteria and pathologic and pathophysiologic mechanisms of GPA, with an emphasis on findings encountered in the realm of head and neck imaging. Particular attention is paid to generating an appropriate differential diagnosis, because many of the imaging features of GPA overlap with those of other diseases, most notably lymphoma and sarcoidosis.

Imaging of the skull base: anatomy and pathology.

The skull base is a critical landmark, separating intracranial from extracranial structures. This intricate anatomic structure has several foramina and crossing structures, which can be a challenge for novices. Comprehensive anatomic knowledge is critical for narrowing the differential diagnosis of lesions that may affect the skull base.

Imaging of ectopic thyroid tissue and thyroglossal duct cysts.

When a child or young adult presents with a mass in the anterior portion of the neck, diagnostic considerations include a thyroglossal duct cyst and ectopic thyroid tissue. These entities are often suspected clinically, and imaging provides an opportunity to evaluate the extent, confirm the diagnosis, and evaluate for complications. Imaging characteristics of a thyroglossal duct cyst as a simple cyst and of ectopic thyroid tissue as a hyperattenuating soft-tissue mass can help identify these lesions at computed tomography (CT); however, intrinsic magnetic resonance, CT, and ultrasonographic imaging characteristics alone cannot be used to confirm the diagnosis.

An algorithm for the management of posttraumatic cervical spondyloptosis.

Posttraumatic cervical spondyloptosis is the most severe form of fracture dislocation. Since its occurrence is uncommon, there is no consensus on its surgical management. Detailed description of five patients who were successfully managed through one approach (posterior or anterior) is presented, a review of the current literature is reported, and biomechanics is provided.

Incidental findings on cone beam computed tomography images.

Background. Cone beam computed tomography (CBCT) has gained widespread acceptance in dentistry for a variety of applications. Most dentists who are not radiologists/trained in radiology are generally not familiar with interpretation of anatomical structures and/or pathosis outside their area of primary interest, as often this was not within the scope of their training.

Anatomy and embryology of the thyroid and parathyroid glands.

The thyroid and parathyroid glands are cervical endocrine glands responsible for metabolism-related functions. Radiologists are frequently asked to evaluate pathology related to the thyroid and parathyroid glands before planned surgical intervention. Knowledge of embryology and anatomy is fundamental in this region because rather complex underlying embryology produces substantial anatomic variation both in the thyroid bed and elsewhere in the neck and mediastinum.

Duplication of the internal carotid artery presenting with severe atherosclerotic stenosis.

Duplication of the extracranial internal carotid artery is a rare anatomic variant. We present the first patient with unilateral duplication of the cervical internal carotid artery with severe stenosis. Stent-assisted percutaneous transluminal angioplasty was successfully performed to restore blood flow.

A case of solitary Blastomyces dermatitidis meningitis.

We present a case of a 35 year-old male with Blastomyces dermatitidis meningitis as the primary presentation of blastomycosis infection, without evidence of involvement outside the CNS at time of discharge. We focus on the magnetic resonance imaging findings, with histopathologic correlation.

Orbital roof encephalocele mimicking a destructive neoplasm.

The purpose of this case report is to report an orbital roof encephalocele mimicking a destructive orbital neoplasm. Orbital roof encephalocele is uncommon but can mimic neoplasm. One potential mechanism for the orbital roof destruction is a post-traumatic "growing orbital roof fracture.

Previous statin use is not associated with an increased prevalence or degree of gradient-echo lesions in patients with acute ischemic stroke or transient ischemic attack.

Background And Purpose: Microhemorrhages on gradient-echo T2*-weighted MRI sequences are often found in patients with cerebrovascular disease and are related to intracerebral hemorrhage. Because statin therapy is associated with increased risk of intracerebral hemorrhage, we investigated whether statin use was also associated with microhemorrhages in patients with acute ischemic stroke or transient ischemic attack.

Methods: We performed a retrospective analysis on prospectively collected data from a stroke registry containing patients with acute ischemic stroke or transient ischemic attack.

Anomalous origins of the calcarine and parieto-occipital arteries.

Understanding cerebrovascular anatomy and its variations is of utmost importance in treating vascular malformations. The two patients presented here demonstrate yet to be reported anomalous origins of the cortical branches of the posterior cerebral artery. In one patient, fetal calcarine arteries were identified arising from the internal carotid arteries bilaterally with no calcarine branches arising from the posterior circulation and the basilar artery giving rise to terminal parieto-occipital arteries.

Imaging for neuro-ophthalmic and orbital disease - a review.

A literature review was performed by content experts in neuro-ophthalmology and neuroradiology using a systematic English-language Medline search (1994-2008) limited to articles with relevance to neuro-ophthalmic and orbital imaging. The information covered in this review includes: (i) the basic mechanics, indications and contraindications for cranial and orbital computed tomography and magnetic resonance (MR) imaging; (ii) the utility and indications for intravenous contrast, (iii) the use of specific MR sequences; (iv) the techniques and ophthalmic indications for computed tomography/MR angiography and venography; and (v) the techniques and indications for functional MR imaging, positron emission tomography scanning and single photon emission computed tomography. Throughout the review accurate and timely communication with the neuroradiologist regarding the clinical findings and suspected location of lesions is emphasized so as to optimize the ordering and interpretation of imaging studies for the ophthalmologist.

Denervation atrophy of motor cranial nerves.

Muscles undergoing denervation demonstrate a variety of imaging appearances in the various stages. It is incumbent on the radiologist to be aware of these changes so as not to interpret these muscles as harboring a tumor or being involved by an inflammatory process. Knowledge of cranial nerve anatomy and the muscles they innervate enables identification of denervation patterns that could implicate more than one nerve and directs the search for the causative lesion.

Horner's syndrome: clinical and radiographic evaluation.

Horner's syndrome (HS) occurs when there is interruption of the oculosympathetic pathway (OSP). This article reviews the anatomy of the OSP and clinical findings associated with lesions located at various positions along this pathway. The imaging findings of lesions associated with HS at various levels of the OSP, classified as preganglionic HS (first- and second-order neuron HS) or postganglionic HS (third-order neuron HS), are demonstrated.

Pathologic conditions of the lower cranial nerves IX, X, XI, and XII.

The glossopharyngeal, vagus, spinal accessory, and hypoglossal cranial nerves can be affected by an acute or chronic process that has an impact on the way the patient presents clinically. Knowledge of nerve pathways and relations to surrounding structures is fundamental when evaluating patients who have lower cranial nerve symptoms. A systematic "segment-based" approach helps to narrow the differential diagnosis Pathologic conditions that cause lower cranial nerve symptoms are presented.

Imaging the craniocervical junction.

Introduction: The craniovertebral junction (CVJ) comprises the occiput, atlas, and axis. Radiographic evaluation of this region involves knowledge of only a few anatomical landmarks, as well as basic normal measurements and relationships to perform CVJ craniometry. Occipital bone anomalies and atlanto-occipital non-segmentation typically produce basilar invagination.

Abnormal hypermyelination in a neonate with Sturge-Weber syndrome demonstrated on diffusion-tensor imaging.

In Sturge-Weber syndrome in neonates, evaluation of the extent of the brain parenchymal involvement is difficult due to the lack of calcification, although it is important for initiation of preventive antiepileptic treatment and prediction of prognosis. We present the first application of diffusion-tensor imaging with fractional anisotropy and ADC maps in a 7-day-old neonate. Abnormal T2 hypointensity in the subcortical white matter corresponded to the areas of increased FA and decreased ADC on diffusion-tensor imaging, which probably represents abnormal hypermyelination.

Vascular lesions of the orbit: more than meets the eye.

Vascular lesions of the orbit may be classified on the basis of their natural history, growth pattern, and histologic composition as capillary hemangiomas, venous vascular malformations, venous lymphatic malformations, arterial and arteriovenous lesions, or neoplasms. Most follow a characteristic pattern of clinical development and have one or more specific imaging features that allow diagnosis. Hemangiomas typically manifest at or soon after birth and subsequently involute.

Head and neck cancer: carcinoma of unknown primary.

Carcinoma of unknown primary is uncommon, estimated to represent only 3% to 5% of all head and neck cancers. Squamous cell carcinoma accounts for 70% to 90% of these lesions, most commonly from sites in the upper aerodigestive tract, including tonsils, base of tongue, nasopharynx, and piriform sinus. Magnetic resonance, computed tomography (CT), and positron emission tomography all play a role in the assessment of patients with an unknown primary.

Organized hematoma of the maxillary sinus: CT findings.

Objective: Organized hematoma of the maxillary sinus is rare. It occurs by organization of the hematoma in an unaerated maxillary sinus. The purpose of this study was to evaluate the CT features of this lesion.

A segmentation-based method for metal artifact reduction.

Rationale And Objectives: We propose a novel segmentation-based interpolation method to reduce the metal artifacts caused by surgical aneurysm clips.

Materials And Methods: Our method consists of five steps: coarse image reconstruction, metallic object segmentation, forward-projection, projection interpolation, and final image reconstruction. The major innovations are 2-fold.