PubMed HealthSearch

Biomedical subjects

Y L Yu

Publications and source records attributed to Y L Yu.

At least 73 records · Page 4Linked to original sources

Temporal lobe and hypothalamic-pituitary dysfunctions after radiotherapy for nasopharyngeal carcinoma: a distinct clinical syndrome.

Eleven patients with combined neurological and endocrine complications after external radiotherapy for nasopharyngeal carcinoma are described. Neurologically, memory disturbance, complex partial seizures and hypodense areas in one or both temporal lobes on CT were typical features. Endocrinologically, hypopituitarism was the prominent manifestation. This constellation of clinical features in a patient with previous radiotherapy to the nasopharynx characterises radiation injury to the inferomedial aspects of the temporal lobes and the hypothalamic-pituitary axis. While the parenchymal brain lesions may mimic metastases or glioma on CT, the associated endocrine disturbance would betray the correct diagnosis. The importance of recognising the hypopituitarism which may be clinically asymptomatic and which is amenable to therapy is emphasised, as is the need for a proper fractionation of the radiation dose to minimise the incidence of these disabling complications.

Adult

No apparent association between HLA and multiple sclerosis in southern Chinese.

HLA-A, -B and -DR antigens have been studied in 34 Chinese patients with multiple sclerosis and 100 normal healthy controls. Unlike patients of other ethnic groups in whom multiple sclerosis is associated with HLA-DR2, there was no obvious association with any HLA antigen in the Chinese patients, although the overall distribution of antigens did not appear typical of the southern Chinese population from which the patients were drawn.

Female

Lacunar syndromes due to brainstem infarct and haemorrhage.

Nine patients with brainstem infarct and two with brainstem haemorrhage presented with pure motor stroke, pure supranuclear facial palsy, sensorimotor stroke or ataxic hemiparesis. Despite the clinical similarity with hemispheric lacunes, brainstem infarcts causing lacunar syndromes probably have a greater tendency to progress. Small brainstem haemorrhages should also be considered as a cause of lacunar syndromes and the difficulty in differentiating them from small infarcts without CT is emphasised.

Aged

Beta-thromboglobulin in cerebral infarction.

Plasma beta-thromboglobulin (BTG) was significantly elevated in the acute phase of 116 atherosclerotic thrombotic (p less than 0.0001) and 36 cardioembolic (p less than 0.005) infarcts but normal for 96 lacunes compared with controls. This elevation persisted into the 6th week after the acute event. Among atherosclerotic thrombotic infarcts, the acute beta-thromboglobulin level showed a tendency to correlate with infarct size on CT and predicted mortality at 6 weeks. These results suggest that platelet aggregation plays a primary role in the pathogenesis of atherothrombosis.

Aged

Hyperglycemia is a stress response in acute stroke.

To explore further the relation between admission glucose concentration and outcome in stroke, we measured glucose, fructosamine, and glycosylated hemoglobin concentrations on admission in 216 patients seen within 24 hours after the onset of their first stroke. Fructosamine concentration reflects the degree of glycemia in the preceding 4-6 weeks and glycosylated hemoglobin concentration reflects that in the preceding 3 months. Based on clinical, computed tomographic, and necropsy findings, strokes were classified as cortical infarction, lacunar infarction, or intracerebral hemorrhage. Analyses were done including and excluding 47 diabetic patients. No correlation between neurologic outcome as mortality and fructosamine or glycosylated hemoglobin concentration was found. Survival showed a significant correlation with admission glucose concentration only for patients with intracerebral hemorrhage. Our results suggest that hyperglycemia is unlikely to worsen the outcome of acute stroke and that hyperglycemia probably represents either a latent diabetic state or a stress response.

Acute Disease

Admission glucose level in relation to mortality and morbidity outcome in 252 stroke patients.

In a prospective study to correlate admission glucose level with neurologic outcome in stroke, 252 acute stroke patients without prior disability and admitted within 24 hours of onset of ictus were assessed. The stroke was classified into one of three types--cortical infarct, lacunar infarct, or intracerebral hemorrhage--by clinical, computed tomographic, and necropsy findings. Fifty-one diabetic patients were excluded from the entire cohort to form a nondiabetic category for analysis. We found that admission glucose level showed a significantly higher degree of correlation with mortality and morbidity (measured as arm function, leg function, and activities of daily living) when cortical (n = 118) and lacunar (n = 58) infarcts were pooled compared with when they were assessed separately. For intracerebral hemorrhage (n = 76), admission glucose level correlated with mortality but not morbidity. This trend persisted despite exclusion of diabetic patients. These results are consistent with previous observations of a correlation between a high admission glucose level and the severity of stroke. The importance of segregating cortical from lacunar infarcts, two groups with a different natural history and prognosis, in any future analysis is emphasized.

Activities of Daily Living

Isolated hypoglossal nerve palsy due to metastatic germinoma in the neck: a ventriculoatrial shunt-related complication.

A 12-year-old boy with suprasellar germinoma was treated with a right-sided ventriculoatrial shunt at diagnosis. He subsequently developed a metastatic neck mass that presented with an isolated right hypoglossal nerve palsy. Radiological investigations showed a vascular tumor and thrombosis of the right internal jugular vein. It is hypothesized that thrombosis at the venous inflow channel allowed local proliferation of the tumor cells that exited from the intracranial cavity via the shunt.

Brain Neoplasms

Cryptococcal infection of the nervous system.

Eighteen patients with cryptococcal infection of the central nervous system seen during a 10-year period were reviewed. Eleven patients (61 per cent) were immunocompromised due to underlying disease and seven of these were on steroids, cyclophosphamide or both. Two-thirds of patients presented with the triad of fever, headache and neck rigidity suggesting meningitis; seizures and mental confusion were uncommon. A high index of suspicion was essential for diagnosis particularly in immunocompromised subjects, and the diagnosis was established by positive Indian-ink preparation, culture or raised antigen titre in the cerebrospinal fluid. CT scan was helpful for diagnosis and progress monitoring. Amphotericin B and 5-fluorocytosine were the mainstay of treatment, and imidazole derivatives and garlic may be helpful adjuncts. Mortality was 39 per cent, but full recovery was the usual outcome in those who survived. The prognosis was worse with immunocompromised patients, and of those who died, comma and/or convulsion on admission and marked cerebral oedema and hydrocephalus on CT were notable features.

Adolescent

Cerebral infarct precipitated by praziquantel in neurocysticercosis--a cautionary note.

A patient who developed a cerebral infarct during the course of praziquantel therapy for neurocysticercosis is described. Destruction of a large number of cysts by praziquantel followed by a massive inflammatory response was likely to have precipitated the event. Caution on the use of this drug in patients with heavy parasite loads is emphasized.

Aphasia

Some dynamic factors in compressive deformity of the cervical spinal cord.

An investigation into the relative elastic and non-elastic components of compressive deformity of the cervical spinal cord has been made. Sixteen patients were examined by computed myelography with the neck flexed and extended, and one fresh specimen of a human spinal cord was studied under reversible transverse compression with the specimen in a stretched and shortened state. In conditions of transverse compression cord tissue undergoes an alteration in viscoelastic properties, manifesting itself as reduced expansion of the compressed segment as the cord shortens, which in some cases is independent of whether the agent is seen to actually contact the cord. The presence of degenerative changes in cord substance probably accentuates this alteration in mechanical properties.

Aged

Syringomyelia and cervical spondylosis: a clinicoradiological investigation.

Eighty eight patients with proven syringomyelia have been studied retrospectively to explore the relationship between syringomyelia and spondylotic degeneration of the cervical spine. When compared with age and sex matched control subjects, they showed no significant increase in incidence or severity of spondylosis or of vertebral subluxation. Duration of symptoms, degree of disability, and the pattern of analgesia or lower motor neurone lesions in the arms did not appear to be related to the development of spondylosis. The onset of moderate spondylosis was, however, earlier than in the controls, and individual cases with a remarkably early onset or unusual site and/or severity of spondylosis and subluxation were encountered, particularly following laminectomy. It was also noted that in a small number of patients the concomitant development of spondylosis contributed to clinical deterioration. It is concluded that while syringomyelia does not have a consistent, major role in the development of cervical spondylosis or vertebral luxation, it may contribute to progression of spinal degenerative disease in some patients.

Adolescent

Central and peripheral SEP defects in neurologically symptomatic and asymptomatic subjects with low vitamin B12 levels.

Somatosensory evoked potentials (SEPs) following median nerve stimulation were abnormal in 7 patients with sensory impairment due to vitamin B12 deficiency. Extensor plantar reflexes indicated a central sensory pathway lesion in 4 cases and absent tendon jerks suggested peripheral neuropathy in 4, but median nerve SEPs indicated a predominantly central lesion without marked peripheral nerve involvement in 6 and an axonal neuropathy without CNS involvement in 1. The latter had evidence of central slowing of conduction in SEPs following posterior tibial nerve stimulation. Consequently, it is suggested that the brunt of sensory pathway involvement usually falls on the CNS, although peripheral neuropathy may occur as the major abnormality in some cases. In 2 patients SEPs showed a marked improvement following treatment with vitamin B12 injections, one consistent with restored central conduction and the other with recovery from peripheral neuropathy. No peripheral or central SEP abnormalities were seen in 18 dairy-produce eating vegetarians with low vitamin B12 levels, although 6 reported mild sensory symptoms suggestive of peripheral neuropathy and 3 had corroborative clinical signs.

Adolescent

Claude's syndrome: clinical and computed tomography correlations.

A patient with Claude's syndrome (ipsilateral fascicular third nerve palsy with contralateral ataxia) in whom computed tomography demonstrated a discrete infarct in the paramedian rostral mesencephalic tegmentum is reported. The vascular supply of the rostral mesencephalon is discussed.

Aged