ABSTRACT
Cervical spondylytic myelopathy (CSM) is common. Magnetic resonance imaging (MRI), although sensitive, often reveals extensive and sometimes clinically irrelevant findings. The purpose of this study was to investigate the usefulness of central motor conduction studies in localizing the rostral level of cord involvement in 6 patients with CSM. Central motor conduction was assessed using high-voltage stimulation for the spinal roots and magnetoelectrical stimulation for the motor cortex, recording from "marker muscles" innervated by successively higher cervical cord segments. Abnormal central motor conduction affected all subjects at C8-T1, 5 subjects at C7, but none at the C5-C6 levels. The MRI showed abnormalities at multiple levels as high as C4. Our results suggest that central motor conduction studies are helpful in localizing the clinically relevant levels of spinal cord compression in CSM and correlate well with motor abnormalities on clinical examination.
Subject(s)
Cervical Vertebrae/physiopathology , Motor Cortex/physiopathology , Neural Conduction/physiology , Spinal Cord Diseases/etiology , Spinal Osteophytosis/complications , Adult , Electric Stimulation , Electromyography , Female , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Motor Neurons/physiology , Spinal Cord/physiopathology , Spinal Cord Diseases/diagnosis , Spinal Nerve Roots/physiopathology , Spinal Osteophytosis/physiopathologyABSTRACT
Although swallowing difficulties (dysphagia) frequently occur in acute brainstem infarction, physiological studies of dysphagia (videofluoroscopy, manometry) are rarely reported. We present a patient with ipsilateral Horner's syndrome, palatal and laryngeal weakness, aphagia, and ipsilateral face and contralateral extremity pin and temperature loss due to lateral medullary infarction confined to the rostral dorsolateral medulla (RDM). Videofluoroscopy showed that the patient was unable to initiate a swallow. Manometry showed a markedly reduced peak pharyngeal pressure and weak pharyngeal contractions. Within 20 months, the patient's neurological deficits resolved, videofluoroscopy showed a normal swallow, and manometry showed normal peak pharyngeal pressure. Correlation of the clinical, physiological, and imaging evaluations shows that aphagia and severe bilateral pharyngeal paresis can result from unilateral RDM infarction. We suggest that, in man, the bilateral medullary swallowing centers function as one integrated center, and that infarction of a portion of this center is sufficient to cause complete loss of swallowing.
Subject(s)
Cerebral Infarction/physiopathology , Feeding and Eating Disorders/physiopathology , Medulla Oblongata/physiopathology , Paralysis/physiopathology , Pharyngeal Diseases/physiopathology , Acute Disease , Cerebral Infarction/complications , Cerebral Infarction/pathology , Deglutition/physiology , Feeding and Eating Disorders/etiology , Feeding and Eating Disorders/pathology , Humans , Magnetic Resonance Imaging , Male , Manometry , Medulla Oblongata/pathology , Middle Aged , Paralysis/complications , Paralysis/pathology , Pharyngeal Diseases/complications , Pharyngeal Diseases/pathologyABSTRACT
We present a family with severe exercise intolerance, progressive proximal weakness, and lactic acidemia. Fifteen of 24 family members in five generations were affected. Since the affected males do not have offspring at this time, the family pedigree is consistent with either maternal or autosomal dominant inheritance. Muscle histochemistry showed ragged-red fibers and electron microscopy showed globular mitochondrial inclusions. Biochemical analysis showed reduced muscle activities of mitochondrial NADH-cytochrome c reductase (1 of 2 patients), succinate-cytochrome c reductase (2 patients), and cytochrome c oxidase (2 patients). For 1 patient, sequence analysis of 44% of the muscle mitochondrial DNA including all 22 transfer RNA regions showed no point mutation with pathogenic significance. Southern blot analysis showed no deletion. Six affected members of the family were treated with methylprednisolone (0.25 mg/kg) for 3 months. Muscle strength, serum lactate, and energy metabolism at rest (measured by 31P magnetic resonance spectroscopy) significantly improved with treatment.
