ABSTRACT
PURPOSE: To illustrate and describe the appearance of both long-standing and relatively recently occurring motor denervation of the hypoglossal nerve and of the third (mandibular) division of the trigeminal nerve (V3), with emphasis on findings particular to MR imaging. METHODS: Findings from 11 patients with V3 denervation and from seven patients with hypoglossal denervation resulting from a variety of abnormalities were reviewed retrospectively. The motor denervation appearance and functional compromise of the affected musculature are described in terms of the chronicity of the denervation process. RESULTS: The appearance of V3 and hypoglossal motor denervation varies with the chronicity of the process. Long-standing denervation results in extensive fatty replacement and a decrease in the size of the affected musculature. Relatively recently occurring denervation results in abnormal contrast enhancement and edemalike signal changes in the denervated musculature. Fatty replacement was observed acutely in hypoglossal denervation but did not manifest until the subacute stage in V3 denervation. Increased volume of the denervated musculature may also accompany acute denervation signal changes. CONCLUSION: V3 and hypoglossal denervation have a variable appearance depending on the chronicity of the process. Recognition of MR imaging patterns of denervation may allow earlier diagnosis of a denervating lesion and may help to distinguish denervation from similar-appearing processes, such as infection or neoplasia.
Subject(s)
Cranial Nerve Diseases/diagnosis , Hypoglossal Nerve/pathology , Motor Neurons/pathology , Nerve Degeneration/physiology , Trigeminal Nerve/pathology , Adipose Tissue/pathology , Adult , Aged , Diagnosis, Differential , Edema/diagnosis , Female , Head and Neck Neoplasms/diagnosis , Head and Neck Neoplasms/secondary , Humans , Male , Mandibular Nerve/pathology , Masticatory Muscles/innervation , Middle Aged , Retrospective Studies , Tongue/innervationABSTRACT
Common and uncommon nonatheromatous diseases affecting the cervical carotid artery are discussed. Specifically, the radiographic and pertinent clinical features of cervical carotid artery congenital variants, dissection, fibromuscular dysplasia, Takayasu's arteritis, and infection are described. Catheter angiography continues to have an important role in the diagnosis of many of these conditions. Magnetic resonance imaging techniques are emerging as a useful adjunct to catheter angiography and occasionally may be the primary imaging modality for diagnosis.
Subject(s)
Carotid Artery Diseases/diagnosis , Aortic Dissection/diagnosis , Angiography , Bacterial Infections/diagnosis , Carotid Artery Diseases/congenital , Carotid Artery Diseases/diagnostic imaging , Carotid Artery Diseases/pathology , Carotid Artery Injuries , Fibromuscular Dysplasia/diagnosis , Humans , Magnetic Resonance Imaging , Takayasu Arteritis/diagnosisABSTRACT
A 1-year-old female infant presented with a large 7-8 cm Ewing's sarcoma of the left parietal calvarium. It deeply indented the subjacent hemisphere. Wide surgical excision was followed by chemotherapy but not radiation. The patient was clinically free of tumor when she expired 9 months later of sepsis. Though primary Ewing's sarcoma of the skull is said to be relatively rare, we have tabulated 37 cases of this disorder, including the present one (we excluded mandibular tumors (> 100 cases) since they are not usually treated by neurosurgeons). The mean age was 11 years and of those available to follow-up, three quarters were tumor-free 6 months to 7 years postsurgery. The remainder survived an average of 21 months. Ewing's tumors of the calvarium generally grant a favorable prognosis following surgery and/or radiation and chemotherapy. Those at the base of the brain may be more difficult to eradicate. In addition to primary Ewing's tumors, metastases to the skull and the brain from other primary sources in the skeleton have been documented in several reports.
Subject(s)
Parietal Bone/surgery , Sarcoma, Ewing/surgery , Skull Neoplasms/surgery , Chemotherapy, Adjuvant , Combined Modality Therapy , Fatal Outcome , Female , Humans , Infant , Parietal Bone/pathology , Sarcoma, Ewing/drug therapy , Sarcoma, Ewing/pathology , Skull Neoplasms/drug therapy , Skull Neoplasms/pathologyABSTRACT
We present a case of an extensive cervicothoracic gangliocytoma in an asymptomatic 9-year-old boy with progressive scoliosis. MR findings were that of a moderately enhancing cervicothoracic intramedullary mass, which throughout most of its length could not be distinguished from the normal spinal cord.
Subject(s)
Ganglioneuroma/diagnosis , Magnetic Resonance Imaging , Spinal Cord Neoplasms/diagnosis , Child , Diagnosis, Differential , Ganglioneuroma/pathology , Ganglioneuroma/surgery , Humans , Male , Neurologic Examination , Spinal Cord/pathology , Spinal Cord/surgery , Spinal Cord Neoplasms/pathology , Spinal Cord Neoplasms/surgeryABSTRACT
We present two cases of ventricular obstruction in which shunting of intracranial cysts resulted in the unexpected finding of ventricular enlargement. By imaging criteria this suggested shunt malfunction [corrected]; however, the clinical presentation dramatically improved. The probable mechanism for this diagnostic pitfall is discussed.
