PubMed Health⌕ Search

Biomedical subjects

M O McCarron

Publications and source records attributed to M O McCarron.

At least 19 recordsLinked to original sources

Quality assurance of neuroradiology in a District General Hospital.

BACKGROUND: An increasing number of neurologists in District General Hospitals (DGHs) rely on local neuroimaging reports from general radiologists. AIM: To determine the level of disagreement between general radiologists and neuroradiologists in reporting neuroimaging from patients referred to a neurologist. DESIGN: Prospective observational study. METHODS: We studied 232 patients referred for a neuroradiologist's report on neuroimaging over a 17-month period. Pre-planned comparisons included primary and secondary report findings, length of report and suggestions for additional investigations. RESULTS: Of the 593 patients assessed during the study period, a neuroradiologist's report was sought for 232 (39%): 119 men, 113 women, mean age 46.1 (SD 17.6) years. Primary findings differed in 37 patients (15.9%) (95%CI 11.5-21.3). Reports from neuroradiologists changed subsequent management in 31 (13.4%) (95%CI 9.3-18.4). Differences in secondary findings occurred in 52 (22.4%) (95%CI 17.2-28.3), and differences in either primary or secondary outcomes in 77 (33.2%) (95%CI 27.2-39.6). The level of disagreement in primary findings was as frequent among patients investigated with magnetic resonance imaging as among computerized tomogram-only patients (p = 0.13). Neuroradiologists recommended additional investigations for 24 patients (10.3%) (95%CI 6.7-15.0) and provided longer reports than general radiologists (p < 0.001). DISCUSSION: Neuroimaging reports of some patients differ substantially between general radiologists and neuroradiologists. Optimal management of neurological patients in DGHs may require timely access to neuroradiologists.

Diagnosis, Differential↗

Secular stroke trends: early life factors and future prospects.

Stroke mortality rates have declined during the second half of the 20th century in developed countries. Possible reasons for this include preventive measures, recent environmental changes impacting on adult health risks, and more distant environmental influences on childhood health. Data from a number of populations in Europe and the USA suggest that a decrease in early life blood pressure, occurring since the beginning of the 20th century, may have been an important determinant of declining stroke incidence rates and cardiovascular disease mortality in general. Advances in stroke epidemiology are increasing the accuracy of case ascertainment, and neuroimaging refinements (particularly MRI) are improving the accuracy of stroke type and subtype diagnoses. Although some risk factors are common to ischaemic and haemorrhagic stroke, there is accumulating evidence of differing aetiology. There is also an increasing recognition that early life factors may influence stroke risk. Despite the encouraging decline in stroke incidence, there is evidence of a recent increase in mean blood pressure in young people observed in the USA and UK, prompting concern that favourable trends in stroke risk may not be maintained. Reducing early life blood pressure in a population and delaying the onset of hypertension, along with effective measures to combat obesity, are required to avoid a reversal in stroke incidence trends in developed countries, and to prevent the anticipated increase in the burden of stroke in developing countries.

Age Factors↗

Location characteristics of early perihaematomal oedema.

BACKGROUND: The natural history and triggers of perihaematomal oedema (PHO) remain poorly understood. Cerebral amyloid angiopathy (a common cause of lobar haemorrhage) has localised anticoagulant and thrombolytic properties, which may influence PHO. We hypothesised that early (within 24 hours) oedema to haematoma volume ratios are smaller in patients with lobar intracerebral haemorrhage (ICH) than in patients with deep ICH. METHODS: Haematoma and PHO volumes were measured in consecutive patients admitted to an acute stroke unit with a diagnosis of spontaneous supratentorial ICH proven by computed tomography. The oedema to haematoma volume ratios were calculated and compared in patients with lobar ICH and deep ICH. RESULTS: In total, 44 patients with ICH were studied: 19 patients had deep ICH, median haematoma volume 8.4 ml (interquartile range (IQR) 4.8 to 20.8), median PHO 8.2 ml (2.8 to 16), and 25 had lobar ICHs, median haematoma volume 17.6 ml (6.6 to 33.1) and median oedema volume 10.2 ml (3.4 to 24.2). Patients with lobar ICH were older than those with deep ICH (65.7 v 57.4 years, p = 0.009) but ICH location did not differ by sex or race. There was no evidence that haematoma or oedema volumes were related to type of ICH (p = 0.23, p = 0.39 respectively). The median oedema to haematoma volume ratios were similar in patients with lobar and deep ICH (0.67 v 0.58, p = 0.71). Controlling for age, sex, and race made little difference to these comparisons. CONCLUSIONS: There are no major location specific differences in PHO volumes within 24 hours of ICH onset. Deep and lobar ICH may have common therapeutic targets to reduce early PHO.

Adult↗

A systematic review of Terson's syndrome: frequency and prognosis after subarachnoid haemorrhage.

OBJECTIVE: To review systematically the frequency and prognostic significance of vitreous haemorrhage in patients with subarachnoid haemorrhage (Terson's syndrome). METHODS: Papers relating to vitreous haemorrhage in patients with subarachnoid haemorrhage were retrieved. The only studies considered were those with at least 10 consecutive cases of subarachnoid haemorrhage with or without vitreous haemorrhage. The frequency of vitreous haemorrhage in such cases was calculated in prospective and retrospective studies. Mortality was compared in patients with and without Terson's syndrome. RESULTS: 154 papers were reviewed. Three prospective studies and six retrospective studies satisfied the inclusion criteria. Of 181 patients with subarachnoid haemorrhage assessed prospectively (mean age, 51.7 years), 24 (13%) had vitreous haemorrhage; among 1086 retrospective records, 37 (3%) had documented vitreous haemorrhage (p<0.001). Patients with Terson's syndrome had higher Hunt and Hess grades than those without (mean grade, 3.6 v 2.6). Patients with Terson's syndrome were also more likely to die (13 of 30 (43%) v 31 of 342 (9%); odds ratio 4.8; p<0.001). CONCLUSIONS: Prospective studies show a higher frequency of Terson's syndrome than retrospective studies, suggesting that vitreous haemorrhage is not well documented. Vitreous haemorrhage is an adverse prognostic finding in patients with subarachnoid haemorrhage.

Comorbidity↗

Association between interleukin-1A polymorphism and cerebral amyloid angiopathy-related hemorrhage.

BACKGROUND AND PURPOSE: It has been suggested that the interleukin-1A (IL-1A) allele 2 is a risk factor for Alzheimer's disease (AD). Because cerebral amyloid angiopathy-related hemorrhage (CAAH) often coexists with AD, we examined the IL-1A polymorphism in CAAH. METHODS: In a case-control study, patients with pathologically verified CAAH, AD patients without intracerebral hemorrhage, and neuropathologically normal control subjects were studied. DNA was extracted from brain tissue, and IL-1A was genotyped. Logistic regression was used to examine the IL-1A polymorphism in CAAH patients with and without AD compared with AD and non-AD control subjects. RESULTS: There were 42 patients with CAAH, 232 AD patients, and 167 non-AD control subjects. In age-adjusted analyses, there was no association between possession of IL-1A allele 2 and risk of CAAH compared with AD control subjects (odds ratio [OR], 0.94; 95% confidence interval [CI], 0.45 to 1.97; P=0.87) or non-AD control subjects (OR, 0.94; 95% CI, 0.47 to 1.87; P=0.86). Stratifying for the presence of apolipoprotein E epsilon2 or epsilon4 demonstrated the known increased risk of CAAH from these lipoprotein E alleles. Subgroup analyses demonstrated a nonsignificant excess of the IL-1A 2,2 genotype in patients with CAAH and AD compared with those CAAH patients who did not have histological evidence indicating AD (OR, 2.17; 95% CI, 0.15 to 122.3; P=0.64). Comparisons between CAAH patients with AD and AD control subjects and between CAAH patients without AD and non-AD control subjects did not demonstrate an association between CAAH and possession of either the IL-1A allele 2 or the 2,2 genotype. CONCLUSIONS: The IL-1A allele 2 or 2,2 genotype does not appear to be a major risk factor for CAAH.

Aged↗

Effect of apolipoprotein E genotype on in-hospital mortality following intracerebral haemorrhage.

OBJECTIVE: To determine the relationship between the apolipoprotein E (APOE) epsilon4 allele and in-hospital mortality from intracerebral haemorrhage (ICH). MATERIAL AND METHODS: Patients admitted to two acute stroke units with ICH were prospectively evaluated and APOE genotyped. In-hospital survival was recorded in 176 patients. RESULTS: There were 85 men and 91 women, mean age 68 years. Fifty-two (30%) of the 176 patients died in hospital. After adjusting for sex, age, hospital, and race, increased age (P = 0.009) and the presence of the APOEepsilon4 allele (P = 0.026) significantly reduced in-hospital survival. CONCLUSION: The APOEepsilon4 allele in this population may be associated with poor survival following ICH.

Age Distribution↗

Superficial siderosis of the central nervous system many years after neurosurgical procedures.

Recurrent haemorrhage into the subarachnoid space causes superficial siderosis, which clinically manifests as cerebellar ataxia, sensorineural hearing loss, and myelopathy. Two patients developed clinical, radiological, and biochemical evidence of superficial siderosis many years after surgery. One had two posterior fossa operations, a left temporal craniectomy, and radiotherapy for a presumed brain tumour before developing clinical evidence of superficial sidersosis 37 years later. The other had small bilateral subdural collections from recurrent shunt revisions following posterior fossa surgery for a Chiari malformation, and then developed deafness and ataxia. The first patient currently has the longest recorded delay between presumed subarachnoid bleeding and clinical manifestations of superficial siderosis. Both patients provide further evidence that superficial siderosis of the central nervous system, a progressive neurodegenerative vascular condition, may be a delayed complication of neurosurgical procedures.

Adult↗

Apolipoprotein E genotype, coagulation, and survival following acute stroke.

The authors hypothesized that divergent influences of the APOE epsilon4 allele on ischemic and hemorrhagic stroke survival might result from differences in coagulation profiles. In 49 hemorrhagic stroke patients, epsilon4 carriers had higher partial thromboplastin time ratios (p < 0.01) than non-epsilon4 carriers. Among 529 ischemic stroke patients, increasing epsilon4 allele dose was associated with improved survival (p = 0.03) after adjusting for baseline NIH stroke scale (p = 0.00001) and partial thromboplastin time ratio (p = 0.01). Relative anticoagulation does not fully explain the survival advantage in epsilon4-carrying ischemic stroke patients.

Alleles↗

Traumatic Brown-Séquard-plus syndrome.

BACKGROUND: In the 1840s Brown-Séquard described the motor and sensory effects of sectioning half of the spinal cord. Penetrating injuries can cause Brown-Séquard or, more frequently, Brown-Séquard-plus syndromes. OBJECTIVE: To report the case of a 25-year-old man who developed left-sided Brown-Séquard syndrome at the C8 level and left-sided Horner syndrome plus urinary retention and bilateral extensor responses following a stab wound in the right side of the neck. RESULTS: Magnetic resonance imaging demonstrated a low cervical lesion and somatosensory evoked potentials confirmed the clinical finding of left-side dorsal column disturbance. At follow-up, the patient's mobility and bladder function had returned to normal. CONCLUSION: This patient recovered well after a penetrating neck injury that disturbed function in more than half the lower cervical spinal cord (Brown-Séquard-plus syndrome).

Adult↗

APOE gene polymorphism as a risk factor for cerebral amyloid angiopathy-related hemorrhage.

Cerebral amyloid angiopathy (CAA) due to the accumulation of amyloid beta-protein (Abeta) occurs in up to half of elderly individuals and in most cases of Alzheimer's disease (AD). Following identification of the apolipoprotein E (APOE) epsilon4 allele as a risk factor for AD, APOE epsilon4 was also found to be associated with asymptomatic CAA. The major clinical manifestation of CAA is stroke due to a lobar hemorrhage. A complex relationship between APOE epsilon4, APOE epsilon2 and hemorrhage associated with CAA (CAAH) is emerging. Pathological studies have demonstrated that APOE epsilon2 is over-represented among patients with CAAH. This remains the case for patients with co-existing Alzheimer's disease, who otherwise have a very low epsilon2 allele frequency. Other forms of intracranial hemorrhage do not share the same association, indicating that APOE epsilon2 has a specific association with CAAH. Patients with the epsilon2 allele and CAAH are more likely to have taken anticoagulant or antiplatelet medication, had hypertension or had minor head trauma than non-epsilon2 carriers. In addition, the epsilon2 allele is specifically associated with CAA-associated microangiopathic changes such as fibrinoid necrosis and concentric splitting of the vessel wall.

Alzheimer Disease↗

Amyloid beta-protein length and cerebral amyloid angiopathy-related haemorrhage.

The relationship between amyloid beta-protein (A beta) length and the apolipoprotein E (APOE) epsilon 2 allele, which is over-represented in cerebral amyloid angiopathy-related haemorrhage (CAAH), has not previously been examined. Of 57 CAA patients studied, 37 had CAAH. All patients, particularly those with CAAH had more blood vessels immunoreactive for A beta 40 than A beta 42 in both the leptomeninges and cerebral cortex. CAAH patients had more A beta 40-immunoreactive blood vessels in the leptomeninges (p < 0.001) and cortex (p = 0.027) than had non-haemorrhage patients. Cortical blood vessels, the usual source of haemorrhage in CAAH, were more frequently A beta 42 immunoreactive in APOE epsilon 2 carriers than in non-epsilon 2 carriers (p = 0.022). The APOE epsilon 2 allele may predispose to CAAH by increasing the seeding of cortical blood vessels by A beta 42.

Aged↗

Absence of cystatin C mutation in sporadic cerebral amyloid angiopathy-related hemorrhage.

In Icelandic pedigrees a cystatin C mutation, glutamine 68 (L68Q), causes autosomal dominant cerebral amyloid angiopathy-related hemorrhage (CAAH). We examined 33 patients with sporadic CAAH for this mutation. None carried L68Q and, including this report, only one of 52 published cases of sporadic CAAH has had the cystatin C mutation. Despite vascular colocalization of cystatin C with amyloid beta-protein, cystatin C L68Q is rare in sporadic CAAH.

Aged↗

Prospective study of apolipoprotein E genotype and functional outcome following ischemic stroke.

BACKGROUND: The apolipoprotein E (APOE) epsilon 4 allele is a marker of adverse outcome following head injury and intracerebral hemorrhage. Transgenic animal data in a focal cerebral ischemia model suggest that the epsilon 4 allele increases infarct size and functional impairment. OBJECTIVE: To determine if APOE genotype is associated with functional recovery from ischemic stroke. DESIGN: Prospective study. SETTING: Stroke service at a university teaching hospital. PATIENTS: Patients with clinical and neuroimaging findings (computed tomography or magnetic resonance imaging) compatible with an acute ischemic stroke. MAIN OUTCOME: Functional outcome by Barthel index (BI) and modified Rankin scale (mRS) was compared for epsilon 3/epsilon 3 patients vs epsilon 4 carriers and vs epsilon 2 carriers at 1 and 3 months. Univariate predictors of 3-month outcome were examined in a multivariate analysis. RESULTS: One hundred eighty nine patients were enrolled: 100 women, 89 men (mean +/- SD age, 69.4 +/- 11.0 years). There were 25 epsilon 2 alleles (frequency, 0.07), 292 epsilon 3 alleles (0.77), and 61 epsilon 4 alleles (0.16). Baseline National Institutes of Health Stroke Scale scores and Oxfordshire Community Stroke Project classifications were similar in all groups (epsilon 3/epsilon 3, epsilon 4, and epsilon 2 carriers). One-month (BI, P = .64; mRS, P = .59) and 3-month (BI, P = .87; mRS, P = .73) outcomes were not associated with possession of either epsilon 4 or the epsilon 2 allele. Baseline National Institutes of Health Stroke Scale scores (P < .001) and age (P = .002) were significant predictors of 3-month BI and mRS outcomes in multivariate analyses. CONCLUSIONS: Although there is a robust influence of APOE polymorphism on functional recovery after some types of brain injury in humans, it does not exert a major influence on injury severity or functional recovery following ischemic stroke. Arch Neurol. 2000;57:1480-1484

Adult↗

Complex regional pain syndrome with selective emotional sudomotor failure.

We report a patient with sympathetically maintained pain following a mild limb injury. Only emotional sudomotor failure was found in the painful limb. Thermoregulatory vasomotor function was intact. However, the patient had other target-specific sympathetic lesions, including thermoregulatory vasomotor failure in a different limb, not associated with pain. We hypothesize that the sympathetic failure preceded the symptoms and that the mild injury may have provoked collateral sprouting of emotional sudomotor fibres, coupling them with somatic sensory fibres to cause continuous pain.

Adolescent↗