Importance of sustainable local government funding in tackling health inequalities in the UK

This article looks at how there is evidence that policies that alter our environment are more effective than those that work to change individual behaviour. In order to create change, a more nuanced methodology to allocate local government funding is needed.

Response-guided neoadjuvant sacituzumab govitecan for localized triple-negative breast cancer: results from the NeoSTAR trial

BACKGROUND

Sacituzumab govitecan (SG), a novel antibody-drug conjugate (ADC) targeting TROP2, is approved for pre-treated metastatic triple-negative breast cancer (mTNBC). We conducted an investigator-initiated clinical trial evaluating neoadjuvant (NA) SG (NCT04230109), and report primary results.

PATIENTS AND METHODS

Participants with early-stage TNBC received NA SG for four cycles. The primary objective was to assess pathological complete response (pCR) rate in breast and lymph nodes (ypT0/isN0) to SG. Secondary objectives included overall response rate (ORR), safety, event-free survival (EFS), and predictive biomarkers. A response-guided approach was utilized, and subsequent systemic therapy decisions were at the discretion of the treating physician.

RESULTS

From July 2020 to August 2021, 50 participants were enrolled (median age = 48.5 years; 13 clinical stage I disease, 26 stage II, 11 stage III). Forty-nine (98%) completed four cycles of SG. Overall, the pCR rate with SG alone was 30% [n = 15, 95% confidence interval (CI) 18% to 45%]. The ORR per RECIST V1.1 after SG alone was 64% (n = 32/50, 95% CI 77% to 98%). Higher Ki-67 and tumor-infiltrating lymphocytes (TILs) were predictive of pCR to SG (P = 0.007 for Ki-67 and 0.002 for TILs), while baseline TROP2 expression was not (P = 0.440). Common adverse events were nausea (82%), fatigue (76%), alopecia (76%), neutropenia (44%), and rash (48%). With a median follow-up time of 18.9 months (95% CI 16.3-21.9 months), the 2-year EFS for all participants was 95%. Among participants with a pCR with SG (n = 15), the 2-year EFS was 100%.

CONCLUSIONS

In the first NA trial with an ADC in localized TNBC, SG demonstrated single-agent efficacy and feasibility of response-guided escalation/de-escalation. Further research on optimal duration of SG as well as NA combination strategies, including immunotherapy, are needed.

Divining responder populations from survival data

BACKGROUND

Biomarkers that predict treatment response are the foundation of precision medicine in clinical decision-making and have the potential to significantly improve the efficiency of clinical trials. Such biomarkers may be identified before clinical testing but many trials enroll unselected populations. We hypothesized that time-varying treatment effects in unselected trials may result from identifiable responder subpopulations that may have associated biomarkers.

MATERIALS AND METHODS

We first simulated scenarios of clinical trials with biomarker populations of varying prevalence and prognostic and predictive associations to illustrate the impact of subgroup-specific effects on overall population estimates. To show a real-world example of time-dependent treatment effects resulting from a prognostic and predictive biomarker, we re-analyzed data from a published clinical trial (RTOG, Radiation Therapy Oncology Group, 9402). We then demonstrated a quantitative framework to fit survival data from clinical trials using statistical models incorporating known estimates of biomarker prevalence and prognostic value to prioritize predictive biomarker hypotheses.

RESULTS

Our simulation studies demonstrate how biomarker subgroups that are both predictive and prognostic can manifest as time-dependent treatment effects in overall populations. RTOG 9402 provides a representative example where 1p/19q co-deletion and IDH mutation biomarker-specific effects led to time-varying treatment effects and a considerable deviation from proportional hazards in the overall trial population. Finally, using biomarker data from The Cancer Genome Atlas, we were able to generate statistical models that correctly identified and prioritized a commonly used biomarker through retrospective analysis of published clinical trial data.

CONCLUSIONS

Biomarkers that are both predictive and prognostic can result in characteristic changes in survival results. Retrospectively analyzing survival data from clinical trials may highlight potential indications for which an underlying predictive biomarker may be found.

Description of measles D4-Hamburg outbreak in Hamburg, Germany, December 2008 to June 2009, which disproportionally affected a local Roma community

From December 2008 to June 2009 a measles outbreak occurred in the Federal State of Hamburg, Germany. The outbreak affected 216 persons and was caused by a new measles strain termed D4-Hamburg which led to consecutive outbreaks between 2009 and 2011 in at least 12 European countries. Here, we describe epidemiological characteristics of the outbreak and evaluate the control measures taken in Hamburg. In one of the seven boroughs of Hamburg a local Roma community comprised more than 50% of the notified cases.We compared in a stratified analysis the age distribution of these cases with cases of fellow citizens who did not belong to the Roma community. The age group of infants (0-11 months) comprised 33% among the non-Roma measles cases, while in the Roma community only 4% belonged to this stratum. In the stratum of 5-17 year-olds only 8% were affected among the non-Roma cases, whereas in the Roma community 50% belonged to this age group. We discuss the influencing factors that might have led to this difference in age distribution between the two groups.

Description of measles D4-Hamburg outbreak in Hamburg, Germany, December 2008 to June 2009, which disproportionally affected a local Roma community

From December 2008 to June 2009 a measles outbreak occurred in the Federal State of Hamburg, Germany. The outbreak affected 216 persons and was caused by a new measles strain termed D4-Hamburg which led to consecutive outbreaks between 2009 and 2011 in at least 12 European countries. Here, we describe epidemiological characteristics of the outbreak and evaluate the control measures taken in Hamburg. In one of the seven boroughs of Hamburg a local Roma community comprised more than 50% of the notified cases. We compared in a stratified analysis the age distribution of these cases with cases of fellow citizens who did not belong to the Roma community. The age group of infants (0-11 months) comprised 33% among the non-Roma measles cases, while in the Roma community only 4% belonged to this stratum. In the stratum of 5-17 year-olds only 8% were affected among the non-Roma cases, whereas in the Roma community 50% belonged to this age group. We discuss the influencing factors that might have led to this difference in age distribution between the two groups.

Diabetic retinopathy equity profile in a multi-ethnic, deprived population in Northern England

PURPOSE

Equity profiles are an established public health tool used to systematically identify and address inequity within health and health services. Our aim was to conduct an equity profile to identify inequity in eye health across Leeds and Bradford. This paper presents results of findings for diabetic retinopathy in Bradford and Airedale.

METHODS

A variety of routine health data were included and sub-analysed by measures of equity, including age, sex, ethnicity, and deprivation to identify inequity in eye health and healthcare. The Spearman Rank Correlation Coefficient was used to determine the association between variables.

RESULTS

The prevalence of diagnosed diabetes in Bradford and Airedale district is 6.6% compared to 4.3% in nearby Leeds and 5.1% nationally. The age-standardised prevalence of diagnosed diabetic retinopathy within Bradford and Airedale is 2.21% (95% CI 1.54-2.26%), with a disproportionately high prevalence of disease in the Pakistani population and the most deprived parts of the population. There was a poorer uptake of diabetic retinopathy screening in more deprived parts of the district and the proportions with a higher rate of referral to ophthalmology following the screening in Black and Minority Ethnic populations compared with the white population (13.2% vs 6.9%). Uptake of secondary care outpatient appointments is much lower in more deprived populations.

CONCLUSION

Inequalities are inherent in diabetic retinopathy prevalence, diagnosis, and treatment. The reasons for these inequities are multi-factorial and further investigation of reasons for poor uptake of services is required. Addressing the inequalities in eye health and healthcare requires cross-organisational collaboration.

[Teleconferences for national surveillance of infectious diseases and public health events in Germany. Evaluation after three quarters in 2009]

Public health threats are increasingly triggered by events which span across international, national and state level jurisdictions. Innovative surveillance methods are needed to ensure adequate and timely response to such threats. In January 2009 the Department of Infectious Disease Epidemiology at the Robert Koch Institute (RKI) established a system of weekly telephone conferences with all competent authorities of the German federal states to identify, discuss and respond to infectious disease events in real-time. A regular and structured platform was developed for use between participants from state level public health authorities, the military and the RKI. During the first three quarters, 46 infectious diseases were covered, including mandatory reports of measles and meningococcal meningitis and outbreaks of cowpox, which does not have to be notified in Germany. Results of a targeted evaluation and a consistently high attendance rate both indicate that the teleconference has met additional needs for supplemental information exchange among participants. The telephone conference has proven to be a useful resource for rapid and direct communication, coordination and evaluation of signals for public health events in Germany.

Increasing case numbers of adenovirus conjunctivitis in Germany, 2010

In 2010 (as of 13 October 2010), the number of adenovirus conjunctivitis cases reported to the Robert Koch Institute in Berlin, Germany, has increased by more than 250% compared with same period in the previous two years. An investigation was initiated to identify spatial or temporal clusters, possible sources of infection and potential connections to cases abroad. The analysis did not show a disproportionately affected sex or age group, but many infections were preceded by exposure to ophthalmological facilities, communal facilities or public places.

Increasing case numbers of adenovirus conjunctivitis in Germany, 2010

In 2010 (as of 13 October 2010), the number of adenovirus conjunctivitis cases reported to the Robert Koch Institute in Berlin, Germany, has increased by more than 250% compared with same period in the previous two years. An investigation was initiated to identify spatial or temporal clusters, possible sources of infection and potential connections to cases abroad. The analysis did not show a disproportionately affected sex or age group, but many infections were preceded by exposure to ophthalmological facilities, communal facilities or public places.

Multidisciplinary approach to carotid stenting

BACKGROUND

Stroke neurologists, vascular surgeons, interventional neuroradiologists and interventional cardiologists have embraced carotid angioplasty and stenting (CAS) because of potential advantages over carotid endarterectomy (CEA). At Austin Health, a multidisciplinary neuro-interventional group was formed to standardise indications and facilitate training. The aims of this study were to describe our organisational model and to determine whether 30-day complications and early outcomes were similar to those of major trials.

METHODS

A clinical protocol was developed to ensure optimal management. CAS was performed on patients with high medical risk for CEA, with technically difficult anatomy for CEA, or who were randomised to CAS in a trial.

RESULTS

From October 2003 to May 2008, 47 patients (34 male, mean age 71.5) underwent CAS of 50 carotid arteries. Forty-three cases had ipsilateral carotid territory symptoms within the previous 12 months. The main indications for CAS were high risk for CEA (n= 17) and randomised to CAS (n= 21). Interventionists were proctored in 27 cases. The procedural success rate was 94% with two cases abandoned because of anatomical problems and one because of on-table angina. Hypotension requiring vasopressor therapy occurred in 12 cases (24%). The duration of follow up was one to 44 months (mean 6.8 months). The 30-day rate of peri-procedural stroke or death was 6% and the one-year rate of peri-procedural stroke or death or subsequent ipsilateral stroke was 10.6%. Restenosis occurred in 13% (all asymptomatic).

CONCLUSION

A multidisciplinary approach is a useful strategy for initiating and sustaining a CAS programme.

[Vaccinations in early infancy -- results of an epidemiological cross-sectional study in Hamburg]

BACKGROUND

National recommendations for vaccine policies in Germany were changed in 2001. Following this advice childhood vaccination for nine preventable diseases including measles, mumps, and rubella (MMR) should be completed within the first two years of life. To achieve this it is recommended that plurivalent combination vaccines should be used. As data on current practice is generally rare and not available for the State of Hamburg, a cross-sectional study amongst families from Hamburg with children born during the year 2000 was conducted between April and August 2003.

METHODS

A random sample from the resident register was drawn. Structured telephone interviews were conducted. Information on vaccine status and time of vaccination was collected based on individual vaccination documents.

RESULTS

366 families were included in the study. 286 families (78 %) provided information. For 223 families the statements were reliably confirmed. In this group 180 children (80.7 % CI 76 - 86 %) had received at least one dose of MMR vaccine. 112 (50.2 % CI 44 - 57 %) had received two doses. Within the recommended time intervals 49 % had received the first, respectively 46 % had received the second MMR vaccination. A hexavalent contains vaccine containing the other six antigens was used for 138 of the 223 children (62 % CI 55 - 68 %). For 84 of those children (61 %) vaccination was completed with four doses. For 73 children other combinations including single valent vaccines were used. Among those for only 20 children (27.3 %) a completed vaccination status was reached during the recommended time interval. This gap was mainly due to missing hepatitis B vaccinations. The chance for their vaccination to be completed was more than twice as high for children who received the hexavalent combination vaccine compared to the others (RR 2.5; 95 % CI 1.6 - 3.9).

DISCUSSION

The results indicate that the recommendations to complete MMR vaccinations earlier are recognised. Nevertheless about half of the children were vaccinated later than recommended. In order to achieve vaccination coverage which will allow to achieve the goal of measles eradication substantial efforts are still required. Due to relatively large rates of incomplete vaccinations for the other antigens activities should focus on a timely completion of the gaps. The potential of combination vaccines to reach this aim is evident.

Conceptional considerations for a German influenza pandemic preparedness plan

A pandemic appearance of influenza A virus must be expected at any time. The limitations of health preserving and life-saving resources, which will inevitably be reached in the event of a pandemic, will be accompanied by ethical and possibly social conflicts, which can be lessened or resolved only through precautionary planning, clearly specified competencies and transparent decisions within a social consensus. In case of a shortage of vaccines and virostatic agents, decisions will have to be made with regard to the segment of the population that absolutely must be vaccinated. It is currently estimated that a (monovalent) vaccine developed for a new pandemic strain would only suffice for the single vaccination of approximately half of the German population after a year; only 10-14 million vaccine dosages would be available to provide basic immunization and single boosters to personnel required to maintain basic medical care and essential infrastructure after half a year. In the event of local influenza outbreaks, antiviral chemotherapeutic agents could be used to close the gap until a vaccine can become effective. Even if suitable influenza vaccines and virostatic agents are not sufficiently available at the start of a pandemic, it is still possible to at least prevent an outbreak of two of the most feared secondary infections that accompany influenza: pneumococcal pneumonia or meningitis and illnesses resulting from Haemophilus influenzae. Agreement still needs to be reached with manufacturers for guaranteeing the necessary vaccine production or ensuring that they have a sufficient stock to meet the minimum demand for antiviral agents and agents for symptomatic treatment.

Influenza pandemic: preparedness planning in Germany

The following conceptual framework formed the basis for a common decision made by the health ministers of Germany's 16 federal states to set up an influenza pandemic preparedness plan. The worst case scenario was used, on the basis of the data from the pandemic of 'Spanish flu', in 1918-20. The priority groups for vaccination were assessed, as well as the potentially available antiviral treatments. National policies could be highly improved by a common European view.

[Skelefon framework concept for defence against risks in unusual epidemics: steps by public health offices]

Necessary anti-epidemic measures have to be promulgated or taken immediately in case of a suspected case of pneumonic plague or a viral haemorrhagic fever which can be transmitted from human to human. A live threatening highly contagious infectious disease may occur at any place in Germany. Therefore each health office should have the relevant information on the available infrastructure in Germany concerning treatment and competence centres, diagnostic laboratories, dispatch of samples and patient transportation. They should also be able to give qualified recommendations to physicians and hospitals concerning the necessary measures in such a case. Contacts at risk have to be notified. Based on a risk assessment and the special living conditions of the contact person they should decide if and which further measures have to be initiated, especially in the case of post-exposure prophylaxis, separation and prohibition of work. In general, imported cases of dangerous infectious diseases quickly find the interest of the media, including all the implications resulting from this. A well-organized cooperation with the media and public relations helps to avoid unnecessary irritations and panic.

Dextran reduces embolic signals after carotid endarterectomy

One hundred fifty patients undergoing carotid endarterectomy were randomly assigned to receive intravenous 10% dextran 40 or placebo. Transcranial Doppler monitoring of the ipsilateral middle cerebral artery 0 to 1 hour postoperatively detected embolic signals in 57% of placebo and 42% of dextran patients, with overall embolic signal counts 46% less for dextran (p = 0.052). Two to 3 hours postoperatively, embolic signals were present in 45% of placebo and 27% of dextran patients, with embolic signal counts 64% less for dextran (p = 0.040). We conclude that dextran reduces embolic signals within 3 hours of CEA.

An outbreak of Salmonella blockley infections following smoked eel consumption in Germany

In June 1998, an increased number of persons with Salmonella blockley infection were reported from one German state. Because S. blockley is extremely uncommon in Germany, a case-control study was performed in order to find the source. A total of 13 patients met the case definition. Nine of 12 cases and 2 of 21 controls with food consumption histories reported eating smoked eel (OR 28.5; 95% CI 3.9-235.3). The consumed eel came from four different local smokeries, but could be traced back to fish farms in Italy. This outbreak indicates that eel may be a vehicle for salmonella infection and that the smoking process may not eliminate bacterial contamination from raw fish.

Serogroup C meningococcal disease outbreak associated with discotheque attendance during carnival

In the week following a carnival during 19-24 February 1998, an outbreak of meningococcal disease occurred in a rural German county. The available isolates belonged to phenotype C:2a:P1.2,5 and were clonally related by pulsed-field gel electrophoresis. A case-control study was done to identify risk factors for the outbreak and to define possible vaccination target groups. Five persons aged 13-16 years who fell ill during 24-27 February were included in the study. Four of 5 cases and 10 of 32 controls visited local discotheques (OR = 8.8; P = 0.06). Cases also visited discotheques more frequently than controls (chi2 for trend, P = 0.0002). Multiple discotheques during the carnival may have been predominant locations of transmission in this outbreak. Because this risk factor was limited in time, a mass community vaccination campaign was not initiated.

Transcranial Doppler microembolus detection in the identification of patients at high risk of perioperative stroke

OBJECTIVES

Perioperative ischaemic stroke is the leading cause of morbidity and mortality associated with carotid endarterectomy (CEA). The aim was to test the hypotheses that the detection of microembolic ultrasonic signals (MES) with transcranial Doppler ultrasound (TCD) during and after the operation may be of value in identifying patients at increased perioperative stroke risk.

DESIGN

Open prospective case series.

PATIENTS AND METHODS

Eighty-one consecutive patients undergoing CEA with TCD monitoring. Preoperative, intraoperative and interval postoperative TCD monitoring of the middle cerebral artery (MCA) ipsilateral to the operated carotid artery. On-line pre- and intraoperative MES counting and blinded off-line analysis of postoperative MES counts. End-points were any focal neurological deficit and death at 30 days postoperatively.

RESULTS

MES were detected in 94% of patients intraoperatively and 71% of cases during the first postoperative hour. MES counts ranged from 0 to 25 per operative phase (range of median counts 0-8) and from 0 to 212 per hour postoperatively (range of median counts 0-4). Eight cases (10%) developed postoperative MES counts greater than 50/h. Five of these eight cases evolved ischaemic neurological deficits in the territory of the insonated MCA, indicating a strong association between frequent postoperative microembolism and the development of early cerebral ischaemia (chi 2 = 34.2, p < 0.0001). Intraoperative MES were not associated with clinical outcome measures.

CONCLUSIONS

MES counts of greater than 50/h in the early postoperative phase of carotid endarterectomy are predictive of the development of ipsilateral focal cerebral ischaemia.

Transcranial Doppler detected cerebral microembolism following carotid endarterectomy. High microembolic signal loads predict postoperative cerebral ischaemia

Cerebral ischaemia, the most frequent serious complication of carotid endarterectomy (CEA), usually occurs in the early postoperative period and is often the result of thromboembolism. We hypothesized that the early postoperative detection of microembolic ultrasonic signals (MES) with transcranial Doppler ultrasound (TCD) may be of value in identifying patients at risk of postoperative cerebral ischaemia and that the MES rate may be an important determinant in risk prediction. Sixty-five patients undergoing CEA were studied at intervals up to 24 h postoperatively with TCD insonation of the middle cerebral artery ipsilateral to the operation side. Study design was open and prospective with blinded off-line analysis of MES counts. End-points were any focal ischaemic neurological deficit and/or death up to 30 days postoperatively. MES were detected in 69% of cases during the first hour postoperatively with counts ranging from 0 to 212 MES/h (means 19 MES/h; SEM +2- 4.5; median 4 MES/h). In seven cases (10.8%) counts were > 50 MES/h. Five of these seven cases developed ischaemic neurological deficits in the territory of the insonated middle cerebral artery during the monitoring period. The positive predictive value of counts > 50 MES/h for cerebral ischaemia was 0.71. Frequent signals (> 50 MES/h) occur in approximately 10% of cases in the early postoperative phase of CEA and are predictive for the development of ipsilateral focal cerebral ischaemia.

[Epidemiology of infectious diseases--analysis of an increase of infectious hepatitis in Hamburg]

In Hamburg, the incidence of reported cases of infectious hepatitis more than doubled from 1990 to 1991. The increase refers to hepatitis A, B and other forms of hepatitis. The seven public health offices and the local ministry for health, works and social affairs in Hamburg have analysed the development in a computer-based retrospective study comparing the 1990 and 1991 data. The predominantly affected age group of hepatitis A shifted from childhood to young adulthood. The importance of travelling to acquire hepatitis A was less than expected. In all forms of hepatitis the large number of IV-drug users and prisoners was striking.

Venous reflux patterns in the popliteal fossa

Incompetent veins in the popliteal fossa were assessed with duplex ultrasound in 123 legs of 104 patients. In 91 cases the venous reflux was the result of a single incompetent vein draining into the deep system. In 32 cases duplex ultrasound demonstrated a combination of incompetent veins. With the exception of 3 patients duplex scanning accurately localised the incompetent veins and their "junctions" with the deep system. In 48 legs the reflux signal, detected in the surface vein, extended back beyond the "junction" into a proximal segment of the popliteal vein or superficial femoral vein; in most cases the distal popliteal vein remained competent. Six distinct venous reflux patterns were identified in the popliteal fossa, which seemed to correlate with the severity of related clinical symptoms.

Femoropopliteal bypass using autogenous vein and modified human umbilical vein. A comparative study

This study is based on 223 consecutive femoro-popliteal and femorotibial bypass grafts performed between January 1978 and June 1985 at the Western General Hospital. Autogenous vein grafts demonstrated better 5 year patency rates (54%) than modified human umbilical vein (32%). The superiority of autogenous vein was even more marked when anastomoses were to below knee vessels: 56% compared with 26% at 5 years. Grafts anastomosed to the superficial femoral artery had similar long term patency to those anastomosed to the common femoral artery. When grafts were required for severe ischaemia, similar 5 year patency rates were achieved with autogenous vein (35%) and modified human umbilical vein (30%). The 5 year limb salvage rate in severe ischaemia was 72% for autogenous vein and 63% for modified human umbilical vein. The findings confirm that modified human umbilical vein is a satisfactory alternative when autogenous vein is not available.

The detection of early femoro-distal vein graft stenosis by treadmill exercise testing

A prospective study of 125 femoro-distal vein bypass grafts (103 patients) was undertaken to assess the role of treadmill exercise testing in the detection and correction of early vein graft stenosis. Patients were followed at 1,3,6,12 months and then annually with routine clinical assessment, palpation of pulses and resting Doppler ankle/brachial index. In addition, the Doppler index was repeated after 5 minutes exercise on a treadmill set at 5 degrees and 3 km/hr. Follow-up has been carried out for a mean of 24 months (range 3-48 months) and during that time 30 vein grafts (28 patients) were submitted to angiography. This revealed vein graft stenosis in 15, native vessel disease in 11 and no morphologic abnormality in 4. One additional graft was suspected to have a stenosis but occluded before angiography could be carried out. At the time of detection by the treadmill test, 8 of the 15 (53%) confirmed vein graft stenoses, and 4 of 11 (36%) native vessel stenoses would not have been detected by clinical assessment or resting Doppler pressure measurements. The 15 vein graft stenoses which were corrected all remain patent, suggesting that treadmill testing is of value in the detection and prevention of early femoro-distal vein graft occlusion.

Pitfall of venous occlusion plethysmography

The supposition that the lower limb expands uniformly in circumference during venous occlusion has been investigated. The 3 compartments of the calf were found to be expand to differing degrees depending on the volume of muscle within the compartment. The effect of this phenomenon on the measurement of venous outflow and capacitance using an overlapping strain gauge was assessed. When using an overlapping strain gauge, the anatomical site of overlap was found to alter the measured values of outflow and capacitance by as much as 50%. These errors do not arise with strain gauges designed to fit a small range of limb circumferences, so that no overlap occurs. The reproducibility of plethysmography may be enhanced by attention to the site and degree of overlap of gauges which are designed to fit all sizes of limb. Technicians performing venous occlusion plethysmography should be aware of these variations, so that the examination technique can be standardized.

Computer based pattern recognition of carotid arterial disease using pulsed Doppler ultrasound

A minicomputer based system has been developed for studying carotid artery blood flow data obtained for a combined B-mode, pulsed Doppler ultrasound scanner. The goals of this work are to devise and improve techniques for estimating the extent of atherosclerosis at the carotid artery bifurcation. Features are automatically extracted from spectrum analyzed Doppler blood flow data. Five statistical pattern recognition algorithms are compared, with cross validation being used to improve the estimate of classification accuracy. A data collection protocol has been devised in which four sites are studied along each carotid arterial system. Classification of unknowns is done using a hierarchy of three decisions.

Evaluation of carotid bifurcation disease: the role of common carotid artery velocity patterns

We evaluated duplex ultrasonographic velocity patterns from the common carotid artery in 156 patients with arteriographically verified internal carotid artery disease. Flow to zero during diastole in the common carotid was found in three groups of patients: (1) those with flow to zero in both common carotids not related to disease of the carotid bulb; (2) those with a tight (90% to 99%) stenosis in the internal carotid; and (3) those with total occlusion of the internal carotid. Although such flow to zero is commonly observed with total occlusion of the internal carotid artery, it may also be seen with high-grade stenosis. Thus, when found, it is essential to ascertain if flow is indeed present in the internal carotid artery; understanding changes in velocity patterns of the common carotid has improved our overall accuracy in detecting extracranial carotid artery disease.

Ultrasonic duplex scanning for disease of the carotid artery

The duplex ultrasonic scanner combines real-time B-mode imaging with a single-gate, variable-range pulsed Doppler. The detection and categorization of the severity of carotid artery atherosclerosis is achieved by performing spectral analysis of the pulsed Doppler velocity signal obtained from vessels of interest. Using this technique, 750 patients with suspected extracranial carotid artery disease were evaluated between January 1978 and January 1980. One hundred thirty-five of these 750 patients (18%) underwent cerebral arteriography performed with biplanar views of the carotid bifurcation. The degree of stenosis was measured independently in these patients and was available for comparison with the results of duplex scanning and spectral analysis. Duplex scanning correctly detected the presence of disease in 252 of 259 carotid arteries studied (97%). The extent of involvement varied from plaques that produced less than 10% diameter reduction to those that resulted in a total occlusion. The technique was less accurate with lesions that produced less than 10% diameter reduction.

Carotid arterial disease in patients undergoing coronary artery bypass operations

The occurrence of stroke associated with coronary artery bypass operations is approximately 2%. In an attempt to reduce this incidence some centers have proposed carotid thromboendarterectomy for symptomatic and asymptomatic carotid arterial disease in patients undergoing a coronary artery bypass operation. To obtain a better understanding of the incidence of carotid occlusive disease in candidates for the coronary bypass operation and to evaluate the practical use of a noninvasive method to screen patients preoperatively, we evaluated 102 patients preoperatively with an ultrasonic Duplex scanner; 24 studies were requested on the basis of either previous neurologic problems or the presence of a bruit and 78 patients were evaluated as part of a study protocol. In the unrequested group 6% (5/78) of the patients had a stenosis of 50% diameter reduction or more. In the requested group 54% (13/24) had a stenosis of 50% diameter reduction or more. In the postoperative phase one stroke and one transient ischemic attack were noted among the unrequested group and none in those suspected of having carotid disease on clinical grounds. Neither affected patient had a high-grade stenosis. There is little evidence to support the contention that noninvasive screening of patients free of symptoms or signs of carotid disease prior to coronary artery bypass operation is a valuable method of screening for patients who will sustain a focal neurologic event.

Importance of noninvasive ultrasonic-Doppler testing in the evaluation of patients with symptomatic carotid bruits

An ultrasonic Duplex scanner was used to estimate the site and degree of extracranial arterial disease in two groups of patients with asymptomatic bruits. In the first 100 patients only the extent of disease was assessed with 37% of the sides with bruits having high-grade stenoses (greater than 50% diameter reduction) and one-half having lesions which narrowed the internal carotid artery by less than 50%. Seven percent were found to be normal. The remaining 6% had occlusion of the internal carotid artery. In a second group of 81 patients, the effect of the reported findings of the Duplex scan on patient management was reviewed. Only 13 patients underwent angiography and 11 of these were in patients with high-grade stenoses. Five carotid endarterectomies were performed and in each case, the patient had bilateral high-grade lesions. The implications of this diagnostic approach are discussed as well as the need for prospective studies of patients who present with an asymptomatic bruit.