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J H Gillard

Publications and source records attributed to J H Gillard.

53 records · Page 3Linked to original sources
PubMed1998

Evaluation of carotid endarterectomy with sequential MR perfusion imaging: a preliminary report.

BACKGROUND AND PURPOSE: Current indications for carotid endarterectomy are determined by balancing the relative risks of surgery with the benefits of reduced risk of subsequent stroke. Our purpose was to use MR perfusion imaging to assess patients being considered for carotid endarterectomy and to monitor sequential changes in MR perfusion characteristics after surgery. In particular, we wished to determine whether this technique could be used to detect changes that might be related to post-carotid endarterectomy hyperemia. METHODS: We used a single-section gradient-recalled echo sequence to investigate 14 patients being examined before possible surgery for carotid artery disease. In the 12 patients in whom carotid endarterectomy was performed, sequential studies were performed 3 to 5 days after surgery and at 3 months. Analysis of bolus-arrival-time (BAT) images was performed. RESULTS: Significant delays in preoperative BAT images of 0.89 seconds (range, 0.05 to 3.22 seconds) were apparent between hemispheres. Excluding the two patients with contralateral internal carotid artery (ICA) occlusion, early arrival, possibly indicating postoperative hyperemia, was seen in five patients immediately after carotid endarterectomy but resolved within 3 to 5 months after surgery. CONCLUSION: MR perfusion imaging shows differences in BAT between hemispheres in patients with ICA stenosis. Changes in perfusion characteristics after carotid endarterectomy are complex, and early BAT on the operative side can occur soon after endarterectomy in over half those patients without an occluded contralateral vessel. The significance of these findings with regard to patient outcome and risk of postoperative hyperemia requires further investigation.

Aged↗
PubMed1997

MR angiography in acute cerebral ischemia of the anterior circulation: a preliminary report.

PURPOSE: To determine the prevalence of major vessel occlusion in cases of acute cerebral ischemia of the anterior circulation by using MR angiography and to assess the frequency of spontaneous thrombolysis. METHODS: Thirty patients with an initial clinical diagnosis of possible acute stroke of the anterior circulation made within 24 hours of the event were studied with conventional T2-weighted MR imaging and with two-dimensional and three-dimensional time-of-flight MR angiography. Studies were repeated if the initial study showed partial or complete occlusion. RESULTS: Of the 30 patients studied six (20%) had a final diagnosis of a transient ischemic attack and 24 (80%) had a stroke of the anterior circulation as confirmed by T2 abnormalities and persistence of clinical symptoms. Twelve (50%) of the stroke patients had a major vessel abnormality, either partial or complete occlusion, at MR angiography. Of these 12 patients, nine subsequently had follow-up MR angiography, and only two of these had a change in the findings. One patient with diminished flow signal had progression of the occlusion and another patient had flow signal in a vessel where no flow was seen initially. CONCLUSION: MR angiography can show patients with acute cerebral ischemia and major vascular occlusive disease. Of those with partial or complete occlusion, progression of thrombus or spontaneous recanalization occurs infrequently.

Acute Disease↗
PubMed1996

Proton MR spectroscopy in acute middle cerebral artery stroke.

PURPOSE: To investigate the feasibility of performing multisection proton MR spectroscopy in patients with acute stroke, and to determine whether this imaging technique can depict ischemic or infarcted brain regions. METHODS: Multisection proton MR spectroscopy, MR imaging, and MR angiography were performed within 24 hours of stroke onset (mean, 12 hours) in 12 patients who had had a stroke of the middle cerebral artery. Spectra were analyzed from brain regions containing T2 hyperintensity abnormalities on MR images, from regions immediately adjacent to these abnormalities, and from anatomically similar contralateral regions. Areas of brain containing lactate were compared with areas of T2 hyperintensities on MR images. RESULTS: One data set was discarded because of excessive artifacts from patient motion. Regions of T2 hyperintensities on MR images were found to contain elevated lactate (all 11 cases) and reduced N-acetyl-aspartate (10 of 11 cases) relative to contralateral measurements. Lactate levels in regions adjacent to T2 hyperintensities were not significantly different from those of infarcted brain. On the other hand, N-acetyl-aspartate was significantly lower in regions of infarction compared with periinfarct tissue. Areas of brain containing elevated lactate significantly exceeded those of T2 abnormality. CONCLUSIONS: Proton MR spectroscopy is feasible for imaging patients with acute stroke. In the early stages of stroke, tissue containing elevated lactate but no other spectroscopic or MR imaging abnormality can be identified. Such regions may represent an ischemic zone at risk of infarction.

Acute Disease↗
PubMed1995

Intracranial assessment of incontinentia pigmenti using magnetic resonance imaging, angiography, and spectroscopic imaging.

OBJECTIVE: To evaluate patients with incontinentia pigmenti for evidence of cerebrovascular disease using magnetic resonance imaging techniques. DESIGN: A prospective case series of seven patients (four of whom were related) with incontinentia pigmenti using magnetic resonance imaging, magnetic resonance angiography, and multislice proton (1H) magnetic resonance spectroscopic imaging. SETTING: The Johns Hopkins Medical Institutions, Baltimore, Md, a tertiary, referred care center. PATIENTS: Seven patients with a diagnosis of incontinentia pigmenti. RESULTS: Five of the seven patients had abnormal magnetic resonance imaging consistent with small-vessel occlusions. Of these five patients, four had normal magnetic resonance angiography and spectroscopic imaging, and one patient had reduced middle cerebral artery flow on magnetic resonance angiography and increased lactate level in the cerebrospinal fluid on spectroscopic imaging. The remaining two patients had normal magnetic resonance imaging and spectroscopic imaging. Of these two patients, one had normal magnetic resonance angiography and the other had a right supraclinoid internal carotid aneurysm. There was substantial concordance between clinical (ophthalmic/neurologic) and imaging abnormalities. CONCLUSIONS: The central nervous system changes in patients with incontinentia pigmenti may represent the result of small-vessel occlusive phenomena in the brain. These central nervous system findings may share a common pathophysiologic state with the vascular occlusive disease seen in the retinas of these patients. The changes in the retinal vasculature may serve as a potential marker for central nervous system disease. Physicians should be aware of the systemic and debilitating nature of incontinentia pigmenti.

Adult↗
PubMed1994

Acute stroke: evaluation with serial proton MR spectroscopic imaging.

PURPOSE: To investigate the evolution of metabolic changes detectable with proton magnetic resonance (MR) spectroscopic imaging in acute stroke and to compare these findings with those of conventional MR imaging. MATERIALS AND METHODS: A patient with middle cerebral artery stroke underwent conventional proton-density (PD)- and T2-weighted MR imaging, MR angiography, and multisection proton two-dimensional MR spectroscopic imaging over a period of 3 hours to 5 months after symptom onset. RESULTS: On 3-hour MR images, no abnormal signal intensity change was detectable. Spectroscopic images obtained at 24 hours showed localized elevation of cerebral lactate levels. In most regions with high lactate levels, infarction subsequently occurred. In the chronic stage (5 months), the infarct was associated with reduced N-acetylaspartate levels, increased choline levels, and absence of lactate. CONCLUSION: Spectroscopic imaging enables mapping of ischemic and infarcted brain regions with greater sensitivity than does conventional MR imaging.

Acute Disease↗
PubMed1993

Preregistration house officers in the Thames regions: changes in quality of training after four years.

OBJECTIVE: To measure changes in the training and workload of preregistration house officers over four years. DESIGN: Postal questionnaire. SETTING: The Thames health regions. PARTICIPANTS: 1049 preregistration house officers. RESULTS: Response rate was 69% (725 replies). The proportion of house officers officially on duty > 83 hours a week fell from at least 42% to 21%, and the proportion officially on duty < or = 72 hours rose from no more than 9% to 40%. Adequate guidance in breaking bad news increased from 25% to 46% (p < 0.0001; 95% confidence interval for difference, 16.2% to 25.8%) and guidance in pain control increased from 36% to 46% (p < 0.01; 5.0% to 15.0%). The number of house officers attending an induction course increased from 61% to 94% (p < 0.001; 28.9% to 37.1%). There was no change in the proportion unable to attend formal educational sessions because of clinical commitments or in levels of satisfaction with consultants' educational supervision. The median number of inpatients under house officers' care fell from 20 to 17, but the numbers of patients clerked in an average week showed little change. House officers were less satisfied with the clinical experience their post provided (proportion dissatisfied rose from 30% to 39%; p < 0.01; 4.2% to 13.8%) and less enthusiastic about recommending their post to a friend (proportion neutral or not recommending rose from 30% to 42%, p < 0.0001; 7.9% to 16.9%). CONCLUSION: Despite progress in reducing hours of duty and providing induction courses, the training that hospitals and consultants provide for house officers is still unsatisfactory and inconsistent with the General Medical Council's recommendations.

Attitude of Health Personnel↗
PubMed1993

Preregistration house officers in eight English regions: survey of quality of training.

OBJECTIVE: To assess the quality of preregistration house officer training in eight English regions. DESIGN: Postal questionnaire. SETTING: Thames, East Anglian, Mersey, Northern, and Wessex regions. PARTICIPANTS: 1670 preregistration house officers. MAIN OUTCOME MEASURES: Education, hours of work, workload, conditions of work, and attitudes to job and medicine as a career. RESULTS: Response rate was 69% (1146 replies). Most house officers had attended induction courses (1036/1129 (92%)); 74% (757/1024) found them satisfactory. The proportions who had never received adequate guidance on how to break bad news and how to control pain were 59% (670/1135) and 56% (634/1136) respectively. There was much variation between regions. Overall, 65% (736/1138) reported confidence in performing cardiopulmonary resuscitation. Most respondents (95% (1089/1142)) worked an on call rota, 3% (36) a partial shift, and 0.6% (seven) a full shift; 19% (202) were on duty for average weekly hours that exceeded the targets for 1 April 1993. House officers had a median of 20 patients under their care and clerked a median of 10 emergency cases, six routine cases, and two day cases a week. Over half (690/1128 (61%)) could not obtain hot food after 8 pm, 20% (223/1095) did not always have clean sheets available in their on call room, and 45% (462/1036) did not consider the protection of staff against violence to be adequate at their hospital. The most important problems with the preregistration year were inappropriate or non-medical tasks (ranked first by 360 respondents), hours of work (359), and pay for out of hours work (167). Overall 57% (646/1125) would encourage a friend to apply for their post, but only 24% (266/1112) would encourage a friend to take up medicine and 44% (494/1112) would discourage the idea. CONCLUSIONS: House officers' training is deficient in important respects, with inappropriate tasks and heavy clinical workloads impeding the provision of proper education.

Attitude of Health Personnel↗
PubMed1993

CPR and the RCP (2). Training of students and doctors in UK medical schools.

We asked British medical schools and teaching hospitals about the training they offer to medical students and hospital doctors in cardiopulmonary resuscitation. The response rate was 96%. Training that is practical and consistent with guidelines is offered to nearly all students and house officers, often by consultants. Training for other junior doctors and consultants is much less common. The organisation of training is haphazard, and many hospitals have no resuscitation training officers. As a result, few doctors receive the frequent retraining needed to maintain competence in managing cardiopulmonary arrest.

Attitude of Health Personnel↗
PubMed1992

Allocation of junior hospital doctors to pre-registration posts: does Britain need a national matching scheme?

The attitudes of British postgraduate deans and senior medical students to the introduction of a national pre-registration house officer allocation scheme were investigated by postal questionnaire. Several postgraduate deans expressed interest, but most were not in favour of the proposal. Students held similar views. The advantages and disadvantages of a national scheme are discussed.

Attitude of Health Personnel↗
PubMed1990

Preregistration house officers in the four Thames regions: I. Survey of education and workload.

OBJECTIVE: To assess the education and workload of preregistration house officers in the four Thames regions. DESIGN: Postal questionnaire. SETTING: Teaching and non-teaching hospitals in the four Thames regions. PARTICIPANTS: 1064 Preregistration house officers. RESULTS: Response rate was 70% (740 replies). Nine per cent of house officers (66/729) worked a rota of one in two. The average house officer had 20.4 inpatients under his or her care and admitted 23.2 patients per week. Sixty two per cent of house officers (459/740) felt that they spent an excessive amount of time on non-medical tasks of no educational merit; 75% (546/725) had never received adequate guidance on breaking bad news and 64% (467/729) had never received adequate guidance on pain control; 34% (249/731) did not feel confident that they could perform cardiopulmonary resuscitation unsupervised. House officers would tend to recommend their post to a friend. CONCLUSIONS: There are deficiencies in preregistration training in the four Thames regions. The General Medical Council's requirements are not being heeded.

Accreditation↗
PubMed1990

Preregistration house officers in the four Thames regions: II. Comparison of education and workload in teaching and non-teaching hospitals.

OBJECTIVE: To detect differences in the education and workload of preregistration house officers working in teaching and non-teaching hospitals. DESIGN: A postal questionnaire. SETTING: Teaching and non-teaching hospitals in the four Thames regions. PARTICIPANTS: 1064 Preregistration house officers. RESULTS: Response rate was 61% for teaching hospitals and 73% for non-teaching hospitals. House officers in teaching hospitals had significantly fewer inpatients under their care (house physicians 16.9 v 22.9, house surgeons 17.9 v 20.3) and admitted fewer emergency patients per week (house physicians 7.7 v 12.7, house surgeons 6.5 v 9.8). More house officers in teaching hospitals reported that they had too few patients to provide adequate clinical experience. More of their time was consumed by administrative activities devoid of educational value. CONCLUSION: Preregistration house officer posts at teaching hospitals provide less clinical activity and are perceived as less educationally satisfactory by their holders than those elsewhere.

Accreditation↗
PubMed1990

The allocation of pre-registration house officer posts in the four Thames regions: a survey of house officer opinion.

The satisfaction of pre-registration house officers with the operation of, and outcome of participation in, their medical school's allocation scheme for house officer posts was investigated by postal questionnaire. Satisfaction with outcome was generally high. Significant differences are reported between medical schools in participation rates in allocation schemes and in satisfaction with the operation of the schemes. The operation of the ranking schemes used at Guy's and St Bartholomew's Hospitals is shown to be significantly less satisfactory. Reasons for these findings are examined.

Attitude of Health Personnel↗
PubMed1988

The allocation of house officer posts: a UK survey.

The methods of allocation of house officer posts at British medical schools were investigated by postal questionnaire. Three categories were found: a free market, a matching process between student and consultant preferences, and the use of in-course assessments, the matching process being the most popular. Many medical schools had changed their method of house officer allocation since 1969, but often with unsatisfactory results.

Attitude of Health Personnel↗
PubMed1986

Anatomical validation of middle cerebral artery position as identified by transcranial pulsed Doppler ultrasound.

The basal cerebral arteries were insonated using transcranial pulsed Doppler ultrasound (TPDU) at 2 MHz. The Doppler sample volume (SV) depths at which signals were obtained which could be attributed to the middle, anterior and posterior cerebral arteries (MCA, ACA and PCA) were compared with measurements in adult cadavers and with B-scan ultrasound studies in infants. The depth of the internal carotid artery (ICA) terminal division into ACA and MCA was closely correlated for both groups. In adults, it was found at 5.6 +/- 1.0 cm using TPDU while in cadavers it was found at 5.3 +/- 0.5 cm from the temporal bone. In infants, it was found at 3.2 +/- 0.3 cm for the right side, and 3.2 +/- 0.2 cm for the left side using TPDU, and at 3.4 +/- 0.4 cm and 3.4 +/- 0.5 cm for right and left sides respectively using B-scan ultrasound. The mean depth of the MCA mid-point in infants as defined by TPDU and B-scan was also closely correlated, with values of 2.8 +/- 0.3 cm and 2.7 +/- 0.3 cm for right and left sides respectively using TPDU and of 2.8 +/- 0.4 cm and 2.7 +/- 0.4 cm for right and left sides respectively using B-scan ultrasound. Values for the most lateral part of the MCA did not correlate. In adults, signals from the ACA and PCA were obtained at greater SV depth than the MCA, thus preventing confusion.

Adult↗