Synchronized, interactive teleconferencing with digital cardiac images

St James's Hospital is a tertiary referral center for percutaneous intervention and cardiothoracic surgery for a number of referring hospitals. This article reports on the development and implementation of a synchronized, interactive teleconferencing system for cardiac images that links St. James's Hospital with a remote site (Sligo General Hospital) and overcomes the problems of transmission of large image files. Teleconferencing was achieved by setting up lossless auto transmission of patient files overnight and conferencing the next morning with linked control signals and databases. As a suitable product was not available, a commercially new software was developed. The system links the imaging databases, monitors and synchronizes progress through imaging sequences, and links a range of image processing and control functions. All parties to the conference are ensured that they are looking at the same images as they are played or at specific aspects of an image that the other party is highlighting. The system allows patient management decisions to be made at a weekly joint teleconference with cardiothoracic surgeons and interventional cardiologists from both sites. Rapid decision making was facilitated with 70% of decisions obtained within 24 h, and 88% within 1 week of their procedure. In urgent cases, data can be transmitted within 20 min of the diagnostic procedure. The system allows increased access to angiography for patients living in rural areas, and provides a more focused referral for revascularization. Participation of the referring cardiologist has improved the quality of decision making.

Serum levels of soluble CD163 correlate with the inflammatory process in coeliac disease

BACKGROUND

In coeliac disease, following the introduction of a gluten-free diet, monitoring mucosal disease activity requires repeated small intestinal biopsies. If a test measuring a circulating inflammatory marker was available, this would be clinically valuable.

AIM

To determine if levels of soluble CD163, a scavenger receptor shed by tissue macrophages, correlated with the inflammatory lesion in coeliac disease.

METHODS

Serum samples were collected from 131 patients with untreated coeliac disease, 40 patients with treated coeliac disease, 92 non-coeliac disease control subjects and 131 healthy controls. A capture enzyme linked immunosorbance assay was established to measure levels of soluble CD163 in sera. The extent of the histological lesion in coeliac biopsies was assessed using a Marsh grading system.

RESULTS

Levels of CD163 in untreated coeliac subjects were significantly elevated when compared with the treated coeliac patients, the disease control group and the healthy control subjects (P < 0.0001 in each instance). Moreover, coeliac patients with the most marked histological lesion (Marsh 3) had significantly higher levels of soluble CD163 than patients with Marsh grade 2 lesions (P < 0.0004), with grade 1 lesions (P < 0.0001) and grade 0 lesions (P < 0.0001).

CONCLUSIONS

Measurement of soluble CD163 may be a useful method of monitoring the inflammatory lesion in coeliac disease.

Psychiatric presentation of voltage-gated potassium channel antibody-associated encephalopathy. Case report

Voltage-gated potassium channel antibody encephalopathy, a rare cause of limbic encephalopathy, typically presents with memory impairment and seizures. Psychiatric symptoms have not been emphasised in the literature. Here we describe a 58-year-old man who presented with panic attacks and psychogenic non-epileptic seizures and, later on, developed delusions and hallucinations and then confusion. He was found to have antibodies to voltage-gated potassium channels. Treatment with immuno-modulatory therapy resulted in almost complete recovery.

Survival of antibiotic resistant and antibiotic sensitive strains of E. coli O157 and E. coli O26 in food matrices

Escherichia coli O157:H7 or E. coli O26, which were AS (antibiotic sensitive), AR (laboratory created antibiotic resistant mutants), or naturally MAR (multi-antibiotic resistant), were inoculated into laboratory media, yoghurt or orange juice and their growth/survival monitored during enrichment at 37 degrees C or storage at 4 degrees C. The strains were also inoculated into minced beef and their thermal inactivation (D-values) examined at 55 degrees C, with and without a prior heat shock at 48 degrees C. The growth kinetics (lag phases, growth rates) of the VTEC (verocytotoxigenic E. coli), incubated over 24 h at 37 degrees C in laboratory media, were similar regardless of the presence or absence of antibiotic resistance. In yoghurt and orange juice, E. coli O157:H7 MAR died off significantly faster (P<0.05) than any of other VTEC strains examined. E. coli O157:H7 MAR was also found to be significantly more heat sensitive (P<0.05) than the other VTEC strains tested. The reasons for the observed differences in survival of the different VTEC strains and the link between antibiotic resistance and survival in VTEC organisms are discussed.

Antimicrobial resistance in Irish isolates of verocytotoxigenic Escherichia coli (E. coli)—VTEC

This study compared the antimicrobial resistance profiles of Escherichia coli O157:H7 isolates (n=257) recovered from bovine hides, minced beef and human clinical samples in Ireland, to those profiles of a range of Irish non-O157 E. coli (O111 and O26) isolates (n=31) from a variety of clinical and veterinary sources. Four multi-drug resistant (MDR) E. coli O157:H7 food isolates were identified, with resistance to 10 (1 isolate), 6 (1 isolate) and 4 (2 isolates) antimicrobial agents, respectively. Two of these isolates (resistant to 7 and 4 antimicrobial classes) were characterised further by molecular methods and found to contain class 1 integrons along with a beta-lactamase-encoding tem-1 gene. Transfer of antimicrobial resistance (ampicillin, streptomycin and sulphonamides), the tem-1 gene and markers (int1, qacEDelta1, sul1) characteristic of class 1 integrons were evident in one MDR isolate (resistant to 4 antimicrobial classes) when conjugation and transformation experiments were performed. A clinical isolate and a veterinary isolate of the O111 serotype were MDR and resistant to 4 and 3 antimicrobial classes, respectively. These data suggest that the prevalence of antimicrobial resistance among the three VTEC serotypes examined in this study is low. However, these organisms may become a public health risk should they enter the food chain.

The clinical dementia rating sum of box score in mild dementia

BACKGROUND

Making an early diagnosis of dementia is becoming increasingly important, but is difficult in practice. The Clinical Dementia Rating (CDR) scale is a widely used dementia staging instrument, yielding a global score and a summated score (sum of box score). This study examines the utility of the CDR sum of box score, rather than the CDR global score, in making a diagnosis of early dementia.

OBJECTIVE

To determine whether the CDR sum of box score is predictive of an ICD-10 diagnosis of dementia in cases with mild cognitive deficits.

METHODS

Clinical data recorded on our Memory Clinic database were examined for all patients seen over a 6-year period. Data were extracted from 276 first visits in which patients had scored 0.5 using the CDR global score. We examined the relationship between CDR sum of box score and consensus diagnosis of dementia using logistic regression.

RESULTS

We found that increased CDR sum of box score was significantly associated with a higher probability of being assigned an ICD-10 diagnosis of dementia (p < 0.001). The odds ratio for the coefficient of CDR sum of box was 2.3 (95% CI 1.7-3.1), indicating that the likelihood of being diagnosed as having dementia increased by a factor of 2.3 for every point increase on the CDR sum of box score.

CONCLUSION

These findings indicate that the CDR sum of box score provides additional information to the CDR global score in mild cases. The CDR sum of box score is a helpful indicator in making/excluding a diagnosis of dementia in people with mild cognitive deficits.

Sleep disturbance in mild to moderate Alzheimer's disease

BACKGROUND AND PURPOSE

To determine the prevalence of sleep disturbance in a memory clinic population of Alzheimer's disease (AD) patients and identify its clinical correlates.

PATIENTS AND METHODS

Data from 215 attendees at a memory clinic, who were diagnosed with Alzheimer's disease, were examined. This included data from cognitive, functional and neuropsychological assessments. Sleep disturbance was determined using the question about diurnal rhythm disturbance on the BEHAVE-AD questionnaire. Two groups, with and without sleep disturbance, were compared. Group differences were analysed using univariate analysis and stepwise logistic regression analysis.

RESULTS

The prevalence of sleep disturbance in this sample was 24.5%. The BEHAVE-AD 'aggressiveness' (P=0.009) and 'global rating' (P=0.029) (a measure of global impact of behavioural disturbance) were found to be significant predictors of sleep disturbance in AD.

CONCLUSIONS

Sleep disturbance in AD is associated with other behavioural symptoms, notably aggressiveness. Sleep disturbance in AD has significant impact on the patient and/or caregiver. Consideration of co-morbid behavioural symptoms may aid the clinician in choosing a suitable treatment for sleep disturbance in AD.

Equipment standards for interventional cardiology

Interventional radiology has seen rapid growth in cardiology and represents an alternative to hazardous surgery. Recently there has been a substantial growth in the number of procedures being performed and interventional cardiology (IC) procedures are the most common interventional procedures in Europe. Advances in imaging technology have facilitated the development of increasingly complex radiological IC equipment. Currently, the technology is developing at a rate ahead of supporting research, equipment standards and a regulatory framework. International standards play a key role in the design, manufacture and performance of radiological IC equipment. A survey of 12 IC systems (15 imaging chains) was conducted in Irish hospitals. The aim of the study was to assess the imbalance between rapidly advancing technology and existing standards and to propose recommendations for new IC equipment standards. The results demonstrate the need for definitive equipment requirements and standardisation in the design, manufacture, acceptance and maintenance of IC equipment.

Subjective and objective measures of image quality in digital fluoroscopy

There are numerous methods for assessing image quality in diagnostic X ray. In our study we assessed how imaging quality assurance methods perform in practice. Physics assessments were based on IPEM protocols using Leeds test objects. Clinical assessment was based on a questionnaire. A total of 15 systems in three European locations were assessed, covering a range of image intensifier-TV digital fluoroscopy units. Analysis of 274 clinical questionnaires showed that clinical and physics assessments did not place systems in the same order, based on a given image quality parameter. In almost all the comparisons, low level correlation was measured for statistical comparison of rank order (rs < 0.3). However, broad agreement was observed between physics and clinical assessments for image quality associated with contrast and noise. This study emphasises the importance of maintaining links with clinical assessment, when developing quality assurance metrics, and measuring the mutual performance of clinical and physical assessments of image quality.

Exposure variations under error conditions in automatic exposure controlled film-screen projection radiography

Improper automatic exposure control (AEC) termination may result in high overexposures on some radiographic systems. Under AEC, X-ray factors are adjusted automatically to compensate for differences in patient thickness and density. In radiography, AEC is implemented using ionization chambers placed in the film bucky. In this study we deliberately chose incorrect set-up conditions and assessed the response of the AEC system. Two types of incorrect set-up were studied: (1) incorrect selection of bucky radiation detector and (2) simulated misalignment between the X-ray field and light field. The systems tested varied in age from 1 year to in excess of 10 years. In the first test, overexposures of 90 mGy were recorded. Two systems did not meet EC guidelines for improper AEC termination. The second test, misalignment of the X-ray field, was observed to affect the exposure delivered by approximately +/-22%. The maximum dose increase observed, with a chest phantom in the beam, was 165 microGy. Misalignments also resulted in reduced exposures, which may impact on image quality.

Syndromes of behavioural and psychological symptoms in mild Alzheimer's disease

OBJECTIVES

Behavioural and psychological symptoms of dementia (BPSD) are common in Alzheimer's disease (AD), and are associated with significant distress for patient and carer. Certain behavioural and psychological symptoms have been associated with each other, leading to the suggestion that differences in symptom patterns among patients with AD may represent different syndromes within AD. The purpose of this study is to see if patients with AD could be meaningfully classified into syndromes, based on the relationships between their BPSD.

METHODOLOGY

The sample was recruited through a memory clinic. Two hundred and forty first visit patients with a diagnosis of very mild to mild AD were included. BPSD were assessed using the BEHAVE-AD. Latent class analysis was used to assess for different classes or groups of patients within the sample, based on their behavioural and psychological symptoms.

RESULTS

Three classes were identified; Class 1 with a low prevalence of behavioural and psychological symptoms; Class 2 an anxiety/depressive symptom class and Class 3 an aggressive symptom class.

CONCLUSIONS

The three classes (or groups) of patients obtained by LCA in this sample may be explained by a 'latent', as yet, unidentified factor. Further research is required to determine if these classes are stable over time, and to identify possible latent variables.

Infantile bilateral striatal necrosis maps to chromosome 19q

BACKGROUND

Infantile bilateral striatal necrosis (IBSN) encompasses several syndromes of bilateral symmetric degeneration of the caudate nucleus, putamen, and globus pallidus. Autosomal recessive IBSN is characterized clinically by developmental arrest beginning at age 7 to 15 months, dysphagia, choreoathetosis, pendular nystagmus and optic atrophy, and severe progressive atrophy of the basal ganglia on MRI.

OBJECTIVE

To map the gene causing IBSN.

METHODS

A 10-cM genome-wide linkage scan was initially performed on five affected and five unaffected individuals. The extended family was included in the analysis to narrow the candidate region. Logarithm of odds (LOD) score was calculated using the SUPERLINK program.

RESULTS

Linkage to the chromosomal region 19q13.32-13.41 was established (Z(max) = 6.27 at theta = 0.02 at locus D19S412). Recombination events and a common disease-bearing haplotype defined a critical region of 1.2 Mb between the loci D19S596 proximally and D19S867 distally.

CONCLUSION

IBSN maps to the chromosomal region 19q13.32-13.41. The presence of a common haplotype in all the patients suggests that the disease is caused by a single mutation derived from a single ancestral founder in all the families.

Mathematical study of the role of non-linear venous compliance in the cranial volume-pressure test

The role of the cerebral venous bed in the cranial volume-pressure test was examined by means of a mathematical model. The cerebral vascular bed was represented by a single arterial compartment and two venous compartments in series. The lumped-parameter formulation for the vascular compartments was derived from a one-dimensional theory of flow in collapsible tubes. It was assumed in the model that the cranial volume is constant. The results show that most of the additional volume of cerebrospinal fluid (deltaV(CSF)) was accommodated by collapse of the cerebral venous bed. This profoundly altered the venous haemodynamics and was reflected in the cranial pressure P(CSF). The cranial volume-pressure curve obtained from the model was consistent with experimental data; the curve was flat for 0 < or = deltaV(CSF) < or = 20 ml and 35 < or = deltaV(CSF) < or = 40 ml, and steep for 20 < or = deltaV(CSF) < or = 35 ml and deltaV(CSF) > or = 40 ml. For deltaV(CSF) > 25 ml and P(CSF) > 5.3 kPa (40 mmHg), cerebral blood flow dropped. When P(CSF) was greater than the mean arterial pressure, all the veins collapsed. The conclusion of the study was that the shape of the cranial volume-pressure curve can be explained by changes in the venous bed caused by various degrees of collapse and/or distension.

A longitudinal evaluation of behavioural and psychological symptoms of probable Alzheimer's disease

BACKGROUND

Non-cognitive symptoms are a frequent feature of Alzheimer's disease (AD). Much of the literature that has accumulated pertains to cross-sectional prevalence of these symptoms. There has been relatively little attention paid to the longitudinal course of Behavioural and Psychological Symptoms of Dementia (BPSD).

AIMS

The purpose of this study is to examine the longitudinal course of BPSD in a group of patients with mild AD.

METHODS

A retrospective review of a database was performed to identify patients with NINCDS/ADRDA criteria for probable AD and who had been evaluated three times at yearly interval over a two-year period. Fifty-two subjects were identified with probable AD that had completed follow-up for 24 months. The BEHAVE-AD was used to evaluate BPSD and data was analysed using a Markov analysis.

RESULTS

Activity disturbance is a common and relatively persistent symptom in the mild stages of AD. Anxiety, paranoid ideation, and aggression were moderately persistent. Affective symptoms were not persistent with less than half the patients having the symptoms a year later.

CONCLUSIONS

Activity disturbance is common and persistent in early AD. Paranoid and delusional ideation shows moderate persistence and depressive symptoms infrequently last longer than a year. These findings may have clinical relevance for the pharmacological and non-pharmacological management of BPSD.

Development of a quality assurance protocol for peripheral subtraction imaging applications

Peripheral subtraction scanning is used to trace the blood vessels of upper and lower extremities. In some modern C-arm fluoroscopy systems this function is performed automatically. In this mode the system is programmed to advance and stop in a series of steps taking a mask image at each point. The system then repeats each step after the contrast agent has been injected, and produces a DSA image at each point. Current radiographic quality assurance protocols do not address this feature. This note reviews methods of measuring system vibration while images are being acquired in automated peripheral stepping. The effect on image quality pre- and post-image processing is assessed. Results show that peripheral stepping DSA does not provide the same degree of image quality as static DSA. In examining static test objects, the major cause of the reduction in image quality is misregistration due to vibration of the image intensifier during imaging.

Hypercoagulable states in renal transplant candidates: impact of anticoagulation upon incidence of renal allograft thrombosis

INTRODUCTION

Although multiple studies of demographic variables have been associated with allograft thrombosis, these results are not routinely reproducible. Are ESRD patients with hypercoagulable states (HCS) (antithrombin III deficiency, protein S or C deficiency, activated protein C resistance, and anticardiolipin antibodies) at predictably greater risk for allograft thrombosis?

METHODS

Between 1996 and 1999, all renal transplant candidates were screened for hypercoagulability risk factors [HRF] (multiple arteriovenous access thromboses, prior deep vein thrombosis, prior allograft thrombosis, collagen vascular disease, multiple miscarriages, diabetes, autoimmune disease, and Fabry's disease). HRF(+) candidates were then tested for HCS status. We administered preemptive posttransplant i.v. Heparin in HCS(+) patients and observed the impact of this intervention upon the incidence of allograft thrombosis. We compared demographic data and incidence of allograft thrombosis in an historic control (346 patients transplanted between June 31, 1992, and March 5, 1996) not tested for HCS and a study cohort (502 patients transplanted between March 6, 1996, and June 31, 1999) prospectively screened for HRF. HRF(+) patients who were HCS(+) in the study cohort received i.v. heparin immediately after transplant and p.o. warfarin as outpatients.

RESULTS

Demographic characteristics previously implicated in allograft thrombosis were equivalently distributed in both cohorts with the exceptions that more living-donor transplants (33.1% vs. 15.3%) were performed in study cohort, CIT>24 hr occurred in more control patients (37.3% vs. 22.1%) and more study patients (16.7% vs. 0%) received tacrolimus. Hypercoagulable states were found upon reevaluating five of seven controls (71.4%), who lost prior allografts to thrombosis. Hypercoagulable states were prospectively detected in 10 study patients with hypercoagulability risk factors. Most (9 of 10) study patients receiving anticoagulation have achieved long-term allograft function. Study group allograft thrombosis incidence was reduced (1.59% vs. 4.05%). Hypercoagulable states were demonstrated in most episodes of allograft thrombosis. Control patients who lost prior allografts to thrombosis were anticoagulated after retransplantation and 100% achieved long-term allograft function.

CONCLUSIONS

Long-term allograft function has been achieved in 90% of study patients when prophylactically anticoagulating study patients with hypercoagulable states. A 2.6-fold reduction in the expected incidence of allograft thrombosis was observed in anticoagulated patients with hypercoagulable states.

Chlamydia trachomatis infection in women: bad news, good news, and next steps in prevention

Chlamydia trachomatis causes largely asymptomatic infections that can lead to pelvic inflammatory disease, infertility, ectopic pregnancy, and chronic pelvic pain. Screening women routinely is critical to controlling the epidemic of this disease. Testing innovations now make diagnosis easier, and simple treatment regimens may improve compliance with medications and increase cure rates, but testing and treatment must be coupled with improved screening efforts and effective partner services. Ongoing research may point to other interventions that will increase our success in fighting chlamydial infections.