Faculty Bibliography

BACKGROUND:Large arachnoid granulations that protrude into dural venous sinuses and partially obstruct outflow are an underappreciated etiology of pulsatile tinnitus (PT). Endovascular dural venous sinus stenting is thought to diminish turbulent venous outflow and may relieve obstruction caused by arachnoid granulations. METHODS:Four patients at two institutions were evaluated for unilateral PT. Magnetic resonance imaging and digital subtraction angiography revealed moderate-to-severe stenoses from large arachnoid granulations within the implicated transverse sinus. All patients underwent venous manometry and endovascular sinus stenting. RESULTS:All patients experienced immediate and complete remission of their PT. Stenoses were relieved by a mean of 93% by Warfarin-Aspirin Symptomatic Intracranial Disease criteria. There were no procedural or periprocedural complications. All patients continued to report complete symptom resolution at a mean of 8-month follow-up. CONCLUSIONS:PT from arachnoid granulations are an underappreciated pathomechanism. Endovascular dural venous sinus stenting is an effective intervention for treating unilateral PT secondary to large arachnoid granulation.

Spine trauma represents a common indication for imaging in the emergency department. Multidetector CT imaging, with its advantage of multiplanar reconstructions and fast image acquisition, is the technique of choice in the initial assessment of a patient with poly-trauma. While many simple spinal fractures are adequately evaluated on 2D multiplanar reconstruction images, more complex, potentially displaced fracture patterns can be more fully highlighted on 3D reconstructions. Compared with conventional volume-rendering techniques, cinematic rendering uses a complex illumination model to create a more pho-torealistic representation of the fracture patterns, images that are certain to excite both trainees and clinicians. This review demonstrates the educational value and clinical utility of 3D cinematic rendering images in understanding complex spinal column injuries. Learning Objective: To demonstrate the methodology, clinical applicability, and educational utility behind 3D photorealistic cinematic rendering images of spine injuries, with emphasis on the "tension bands" biomechanical concept.

Radiographic imaging plays an important role in the diagnosis and treatment of paragangliomas. Diagnosis and treatment should be performed as a team effort, with all the involved disciplines working together to provide the best possible individualized work-up and treatment plan for the patient.

Magnetic resonance (MR) imaging is the imaging modality of choice for evaluation of acute traumatic musculotendinous injuries of the knee. Three discrete categories of acute injuries to the musculotendinous unit can be defined: muscle contusion, myotendinous strain, and tendon avulsion. Among the quadriceps muscles, the rectus femoris is the most susceptible to injury at the myotendinous junction due to its superficial location, predominance of type II fibers, eccentric muscle action, and extension across two joints. Among the muscles of the pes anserinus, the sartorius is the most susceptible to strain injury due to its superficial location and biarticular course. The classic fusiform configuration of the semimembranosus along with a propensity for eccentric actions also make it prone to strain injury. MR imaging findings associated with rupture of the iliotibial tract include discontinuity and edema, which are best noted on coronal images. The same mechanism of injury that tears the arcuate ligament from its fibular insertion can also result in avulsion injury of the biceps femoris. The gastrocnemius muscle is prone to strain injury due to its action across two joints and its superficial location. Injuries of the muscle belly and myotendinous junction of the popliteus are far more common than tendinous injuries

Dermoid cysts of the oral cavity are rare. When they do occur, the most common site is the floor of the mouth. Intralingual dermoid cysts are even more rare, and until now, there were only 15 such reports in the English-language literature. In this article, we describe two additional cases. Magnetic resonance imaging is extremely helpful in establishing a differential diagnosis. Surgical excision is recommended to correct deglutition and speech problems. Its rarity notwithstanding, dermoid cyst should be considered in the differential diagnosis of tongue masses in the younger population

We describe a head tilt technique for use with CT angiography that reduces beam-hardening artifacts in patients with aneurysm clips. This simple maneuver directs the artifacts away from pertinent anatomy, thus increasing the chances for diagnostic accuracy. No significant changes in the CT angiographic protocol are required, and the maneuver can easily be combined with other artifact-minimizing strategies.

We report a case of a basilar artery migraine in a 17-year-old boy with transient CT and MR abnormalities after each of two migraine episodes. A repeat MR study 6 months after the last event showed complete resolution of the lesion. Transient abnormalities on brain images similar to those shown in our case have been reported in patients with migraine and other neurologic conditions and are most likely related to cerebral vasogenic edema.

Posterior circulation stroke may rarely be associated with occlusive disease in the anterior circulation, such as in the context of a direct (fetal) origin of the posterior cerebral artery (PCA) from the internal carotid artery (ICA), or in the presence of a persistent trigeminal artery. Carotid dissection is an increasingly recognized cause of anterior circulation ischemia. It is possible that in the setting of certain cerebral hemodynamics, embolism from carotid dissection could cause PCA infarction via a patent posterior communicating artery. CASE DESCRIPTION: We report the MR and MR angiography findings of cerebral dynamics whereby a patient presents with posterior circulation symptoms from anterior circulation pathology: left ICA dissection with subsequent left PCA territory infarction. CONCLUSIONS: Cerebral hemodynamics may allow PCA infarction from carotid disease even in the absence of a fetal PCA origin. This report also broadens the spectrum of stroke associated with carotid dissection.