Publications by authors named "Alexander Vlasak"

Cervical radiculopathy from uncovertebral joint (UVJ) hypertrophy and nerve root compression often occurs anterior and lateral within the cervical intervertebral foramen, presenting a challenge for complete decompression through anterior cervical approaches owing to the intimate association with the vertebral artery and associated venous plexus. Complete uncinatectomy during anterior cervical discectomy and fusion (ACDF) is a controversial topic, many surgeons relying on indirect nerve root decompression from restoration of disc space height. However, in cases of severe UVJ hypertrophy, indirect decompression does not adequately address the underlying pathophysiology of anterolateral foraminal stenosis.

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Disorders of the spine are among the most common indications for neurosurgical and orthopedic surgical interventions. Spinal fixation in the form of pedicle screw placement is a common form of instrumentation method in the lower cervical, thoracic, and lumbar spine. A vital principle to understand for the safe and accurate placement of pedicle screws is the palpable difference between the cortical and cancellous bone, both of which have different material properties and compositions.

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Introduction: Three-dimensional printing and virtual simulation both provide useful methods of patient-specific anatomical modeling for assessing and validating surgical techniques. A combination of these two methods for evaluating the feasibility of spinal instrumentation techniques based on anatomical landmarks has not previously been investigated.

Materials And Methods: Nineteen anonymized CT scans of the thoracic spine in adult patients were acquired.

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Background: Patient safety indicators (PSIs) and hospital-acquired conditions (HACs) are reported quality measures. We compared their prevalence in patients with secretory and nonsecretory pituitary adenoma using the National (Nationwide) Inpatient Sample (NIS), Healthcare Cost and Utilization Project, Agency for Healthcare Research and Quality.

Methods: The NIS was queried for hospitalizations 2002-2014 involving pituitary adenomas.

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Background: Dendritic cell (DC) vaccine efficacy is directly related to the efficiency of DC migration to the lymph node after delivery to the patient. We discovered that a naturally occurring metabolite, sarcosine, increases DC migration in human and murine cells resulting in significantly improved anti-tumor efficacy. We hypothesized that sarcosine induced cell migration was due to chemokine signaling.

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We present a surgical video demonstrating the anatomy and technique of freehand C2 pedicle screw placement using a cadaveric specimen and 3-dimensional simulation software. C2 pedicle screws have been shown to augment cervical constructs and provide increased biomechanical stability compared with pars screws due to the increased length and bony purchase of pedicle screws within the pedicle and vertebral body. The presence of vertebral artery variations within the transverse foramen may preclude pedicle screw placement, and these should be identified on preoperative imaging.

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The brain is the central controller of reproduction and the menstrual cycle. Reproductive endocrinologists spend their days treating patients with perturbations in reproduction as a result of pituitary diseases and manipulate pituitary hormones to enhance fertility and quality of life. Microscopic neuroanatomical images will allow a better understanding of how a tumor in the pituitary might affect vision, or a mass in the brain might cause amenorrhea.

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Dr. Rhoton's key philosophies included "Keep working hard.", "Make surgery more accurate, gentle and safe", "We want perfect anatomical dissections, because we want perfect surgical operations", "Competence without compassion is worthless.

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Background: The fiber tracts of the cerebrum may be a more important determinant of resection limits than the cortex. Better knowledge of the 3-dimensional (3-D) anatomic organization of the fiber pathways is important in planning safe and accurate surgery for lesions within the cerebrum.

Objective: To examine the topographic anatomy of fiber tracts and subcortical gray matter of the human cerebrum and their relationships with consistent cortical, ventricular, and nuclear landmarks.

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