✓ Chordomas are locally aggressive neoplasms with an extremely high propensity to recur locally following resection, despite adjuvant therapy. This biological behavior has led most authors to conclude that en bloc resection provides the best chance for the patient's prolonged disease-free survival and possible cure.The authors present a case of an extensive upper cervical chordoma treated by en bloc resection, reconstruction, and long-segment stabilization. Total spondylectomy of C2–4 with sacrifice of the right C2–4 nerve roots and a segment of the right vertebral artery was performed. The inherent anatomical complexities of en bloc resection in the upper cervical spine are discussed. To the authors' knowledge, this represents the first report of an en bloc resection for multilevel cervical chordoma.
Nucleus rotundus is a prominent nucleus in the dorsal thalamus of nonmammalian amniotes. In one group of reptiles, Caiman crocodilus, previous studies have identified three parts of this neuronal aggregate. The central portion, the rotundal core, which receives visual input from the midbrain and projects to a restricted portion of the telencephalon, contains relay cells only. Previous examinations using Nissl morphology indicated that neurons of the rotundal core were not a homogeneous population of cells. The present investigation utilized another methodology to examine cell populations within the rotundal core, immunoreactivity to the calcium binding proteins, calbindin/calretinin and parvalbumin. Light microscopic observations revealed the following features. First, calbindin/calretinin immunoreactive neurons and parvalbumin immunoreactive neurons were present in the rotundal core. Of these two antibodies, immunoreactivity to calbindin/calretinin was much more robust and calbindin/calretinin immunoreactive neurons were more numerous than parvalbumin cells. Second, neurons immunoreactive to either calbindin/calretinin or parvalbumin were not homogeneous but comprised several populations based on perikaryal shape and size and neuronal process morphology. These results are compared with similar data in other amniotes.
Primary Nocardia infections are uncommon gram-positive bacterial infections caused by aerobic actinomycetes and are typically regarded as opportunistic infections (only one-third of infected patients are immunocompetent). Risk factors include: glucocorticoid therapy, malignancy, organ transplant recipients, human immunodeficiency virus infections, tumor necrosis factor-α inhibitor therapy, diabetes mellitus, alcoholism, inflammatory bowel disease, chronic obstructive pulmonary disease, chronic granulomatous disease, and tuberculosis. The organism has a predisposition to disseminate to the central nervous system and can relapse or progress despite appropriate therapy. Treatment ranges from oral antibiotic management to multiple intravenous antibiotic therapy, with surgical intervention required for severe cases. The surgical options include aspiration or complete excision of abscess contents and capsule. In the present case, we describe the use of bilateral craniotomy with assisted image guidance and multiple abscess excision in an immunocompetent patient with systemic nocardiosis.
✓ Several rare histological variants of ependymoma have been described. The authors report on a patient in whom cervical spinal cord astrocytoma was originally diagnosed after evaluation of a limited biopsy specimen. More abundant tissue obtained during gross-total resection included areas of well-differentiated ependymoma. The histological features of the tumor were extremely unusual, with a major component of pleomorphic giant cells. Its histological, immunohistochemical, and electron microscopic features, however, were consistent with ependymoma. Only two cases of terminal filum and two of supratentorial giant cell variant of ependymoma have been reported. To the authors' knowledge, this represents the first case of giant cell ependymoma of the spinal cord. The clinical significance is the potential for misdiagnosis with anaplastic (gemistocytic) astrocytoma, especially in cases in whom limited biopsy samples have been obtained.
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