Evaluation of methods measuring medication adherence in patients with polypharmacy: a longitudinal and patient perspective

PURPOSE

To explore patients' willingness to have medication adherence measured using different methods and evaluate the feasibility and validity of their combination (i.e., pill counts, a medication diary and a questionnaire assessing adherence two months post-discharge).

METHODS

(1) A cross-sectional evaluation of the willingness of patients with polypharmacy to have their medication adherence measured post-discharge. (2) Medication adherence was monitored during two months using pill counts based on preserved medication packages and a diary in which patients registered their adherence-related problems. During a home visit, the Probabilistic Medication Adherence Scale (ProMAS) and a questionnaire on feasibility were administered.

RESULTS

A total of 144 participants completed the questionnaire at discharge. The majority was willing to communicate truthfully about their adherence (97%) and to share adherence-related information with healthcare providers (99%). More participants were willing to preserve medication packages (76%) than to complete a medication diary (67%) during two months. Most participants reported that preserving medication packages (91%), completing the diary (99%) and the ProMAS (99%) were no effort to them. According to the majority of participants (60%), pill counts most accurately reflected medication adherence, followed by the diary (39%) and ProMAS (1%). Medication adherence measured by pill counts correlated significantly with ProMAS scores, but not with the number of diary-reported problems. However, adherence measured by the medication diary and ProMAS correlated significantly.

CONCLUSION

Combining tools for measuring adherence seems feasible and can provide insight into the accordance of patients' actual medication use with their prescribed regimen, but also into problems contributing to non-adherence.

The development and evaluation of a medication diary to report problems with medication use

Purpose

The study aimed to develop and evaluate a medication diary for patients to report problems with medication use to enable shared-decision making and improve medication adherence.

Methods

Based on a search for existing diaries, a review of the content, and a list of medication self-management problems compiled from previous research, a paper and pencil version of a medication diary was developed. The diary was reviewed for clarity and overall presentation by five healthcare providers and nine patients. Afterwards, user-friendliness was evaluated by 69 patients with polypharmacy discharged from hospital during a quantitative prospective study.

Results

The medication diary consists of several parts: (1) a medication schedule allowing patients to list their medicines, (2) information sheets allowing patients to write down specific medication-related information, (3) a monthly overview to indicate daily whether medication-related problems were experienced, (4) problem sheets elaborating on the problems encountered, (5) space for specific medication-related questions for healthcare providers to facilitate shared-decision making. The review phase resulted in minor textual adjustments and one extra problem in the problem sheet. Most participants, who tested the medication diary for two months, found the diary user-friendly (80%) and easy to fill in (89%). About 40% of participants reported problems with medication use. Half of the patients indicated that the diary can facilitate discussing problems with healthcare providers.

Conclusion

The medication diary offers patients the opportunity to report problems regarding their medication use in a proven user-friendly manner and to discuss these problems with healthcare providers. Reporting and discussing problems with medication use can serve as a first step towards making shared decisions on how to address the problems encountered.

Prevalence, risk factors and diagnostic accuracy of non-invasive tests for NAFLD in people with type 1 diabetes

Background & Aims

The epidemiology of non-alcoholic fatty liver disease (NAFLD) in people with type 1 diabetes (T1D) is not yet elucidated. This study aimed to assess the diagnostic accuracy of non-invasive tests for NAFLD, to investigate the prevalence and severity of NAFLD, and to search for factors contributing to NAFLD in people with T1D.

Methods

In this prospective cohort study, we consecutively screened 530 adults with T1D from a tertiary care hospital, using ultrasound (US), vibration-controlled transient elastography equipped with liver stiffness measurement (LSM) and controlled attenuation parameter, and the fatty liver index. Magnetic resonance spectroscopy (MRS) was performed in a representative subgroup of 132 individuals to validate the diagnostic accuracy of the non-invasive tests.

Results

Based on MRS as reference standard, US identified individuals with NAFLD with an AUROC of 0.98 (95% CI 0.95-1.00, sensitivity: 1.00, specificity: 0.96). The controlled attenuation parameter was also accurate with an AUROC of 0.85 (95% CI 0.77-0.93). Youden cut-off was ≥270 dB/m (sensitivity: 0.90, specificity: 0.74). The fatty liver index yielded a similar AUROC of 0.83 (95% CI 0.74-0.91), but the conventional cut-off used to rule in (≥60) had low sensitivity and specificity (0.62, 0.78). The prevalence of NAFLD in the overall cohort was 16.2% based on US. Metabolic syndrome was associated with NAFLD (OR: 2.35 [1.08-5.12], p = 0.031). The overall prevalence of LSM ≥8.0 kPa indicating significant fibrosis was 3.8%, but reached 13.2% in people with NAFLD.

Conclusions

NAFLD prevalence in individuals with T1D is 16.2%, with approximately one in 10 featuring elevated LSM. US-based screening could be considered in people with T1D and metabolic syndrome.

Impact and Implications

We aimed to report on the prevalence, disease severity, and risk factors of NAFLD in type 1 diabetes (T1D), while also tackling which non-invasive test for NAFLD is the most accurate. We found that ultrasound is the best test to diagnose NAFLD. NAFLD prevalence is 16.2%, and is associated with metabolic syndrome and BMI. Elevated liver stiffness indicating fibrosis is overall not prevalent in people with T1D (3.8%), but it reaches 13.2% in those with T1D and NAFLD.

The Development of Recommendations for Healthcare Providers to Support Patients Experiencing Medication Self-Management Problems

Medication self-management problems such as the inability to correctly obtain, understand, organize, administer or monitor medication can result in negative patient outcomes. However, supportive tools for healthcare providers to assist patients with medication self-management problems are lacking. This study aimed to develop recommendations for healthcare providers to support patients with polypharmacy who experience medication self-management problems. A three-phase study was conducted starting with (1) the mapping of medication self-management problems, followed by (2) a scoping review providing a list of relevant interventions and actions for each respective problem and (3) a three-round modified e-Delphi study with experts to reach consensus on the relevance and clarity of the recommended interventions and actions. The cut-off for consensus on the relevance and clarity of the recommendations was set at 80% expert agreement. Experts could propose additional recommendations based on their professional experience and expertise. The experts (n = 23) involved were healthcare professionals (i.e., nurses, pharmacists, and physicians) with specific expertise in medication management of patients with polypharmacy. Simultaneous with the second e-Delphi round, a panel of patients with polypharmacy (n = 8) evaluated the usefulness of recommendations. Results obtained from the patient panel were fed back to the panel of healthcare providers in the third e-Delphi round. Descriptive statistics were used for data analysis. Twenty medication self-management problems were identified. Based on the scoping review, a list of 66 recommendations for healthcare providers to support patients with the identified medication self-management problems was composed. At the end of the three-round e-Delphi study, the expert panel reached consensus on the relevance and clarity of 67 recommendations, clustered according to the six phases of the medication self-management model by Bailey et al. In conclusion, this study resulted in a guidance document including recommendations that can serve as a resource for healthcare providers to support patients with polypharmacy in case of medication self-management problems. Future research should focus on the evaluation of the feasibility and user-friendliness of the guide with recommendations in clinical practice.

People-centered care and patients' beliefs about medicines and adherence: A cross-sectional study

Introduction

People-centered care (PCC) strategies are believed to improve overall health outcomes. Medicines use is essential for the treatment of many patients with chronic conditions. Non-adherence rates are high and result in poor health outcomes, and increased healthcare utilization and costs. This study aimed to explore the relationship between PCC and adherence to medicines for persons with chronic medicines use, as well as the extent to which patients' beliefs about medicines are influenced by their level of perceived PCC.

Methods

A cross-sectional survey design was performed with adults using at least 3 chronic medicines per day. To measure the degree of medicines adherence, patients' ideas about medication, and PCC, four validated questionnaires were used: The Medication Adherence Report Scale (MARS-5), Beliefs about medicines questionnaire (BMQ), Client-Centered Care Questionnaire (CCCQ) and the Shared Decision Making Questionnaire (SDM-Q-9). Socio-demographics, health status, and drug-related burden were questioned as potential factors to impact the relationship between PCC and adherence.

Results

A sample of 459 persons participated. The mean score on the CCCQ (adjusted to pharmacotherapy) was 52.7 on 75 (sd = 8.83, range [18-70]). The top 20% scored 60 or more, the 20% lowest scores were 46 or less. Adherence levels were high, with a mean score of 22.6 on 25 on the MARS-5, and 88% scoring 20 or more. An increase in PCC corresponded to a higher chance of medicines adherence (OR 1.07, 95%CI [1.02-1.12]), corrected for age, the burden due to chronic diseases, the impact of side effects on daily life, and participants' beliefs about medicines. PCC showed positive correlations with the necessity of medicines use (r = 0.1, p = 0.016) and the balance between necessity and concerns (r = 0.3, p < 0.001); and negative correlations with levels of concerns (r = -0.3, p < 0.001) and scores on harmfulness (r = -0.3, p < 0.001) and overuse of medicines (r = -0.4, p < 0.001).

Conclusion

Patients with chronic medicine use perceived an average high level of people-centeredness in the pharmaceutical care they received. This PCC was weakly positively associated with adherence to their medicines. The higher PCC was evaluated, the more patients believed in the necessity of the medicines use and the better the balance between necessity and concerns. The people-centeredness of pharmaceutical care showed several shortcomings and can still be improved. As such, healthcare providers are advised to actively engage in PCC, and not to wait passively for information provided by the patient.

Shared decision making on medication use between nurses and patients in an oncology setting: A qualitative descriptive study

PURPOSE

(i) To explore patients' and nurses' experiences with medication-related shared decision making (SDM) (i.e., familiarity with the concept, application of medication-related SDM, barriers and facilitators towards its application) and (ii) to explore their role perceptions, respectively.

METHODS

A qualitative study was conducted in which seven interviews with oncological patients and a focus group interview with six nurses were performed. Prior to the interviews, observations of the application of shared decision making were conducted using the OPTION-12 scale. The observations were used exclusively to trigger the group discussion. Data were collected from November 2020 until March 2021.

RESULTS

According to participants, the application of SDM regarding medication by nurses in oncology is limited. Barriers mentioned were health status, medication-related knowledge, the therapeutic nurse-patient relationship, time pressures and workload. Patients valued nurses' contribution to SDM regarding medication and perceived them as key persons because of their advocating, informative, facilitating and supportive role. Individual and contextual factors determined patients' desire for involvement in medication-related decisions.

DISCUSSION

Participants solely concentrated on SDM concerning drug choice and management of therapeutic and adverse effects. The patients' and nurses' experiences and perceptions towards SDM in other domains of pharmaceutical care need further investigation.

Self-Management of Medication on a Cardiology Ward: Feasibility and Safety of the SelfMED Intervention

An intervention, SelfMED, was introduced to facilitate patient self-management of medication during hospitalization. This study aimed to evaluate the feasibility and safety of the SelfMED intervention. All patients in a cardiology ward in a Belgian regional hospital were assessed for suitability for inclusion, applying an evidence-based stepped assessment tool. Patients eligible for medication self-management and willing to participate were included in the study (i.e., consecutive sampling). Patients who self-managed their medication were closely monitored by nurses. The feasibility of medication self-management was evaluated by implementation and completion rates and the opinions of cardiologists. Safety was evaluated by medication administration errors and errors in patients' registration of intake. Of 159 patients assessed for eligibility to self-manage medication in-hospital, 61 were included. A total of 367 medicines were self-managed. Pill counts showed 3 administration errors (0.8%), and on 6 occasions (1.7%) the patient's registration of the intake was incorrect. SelfMED was deemed feasible within the hospital ward. In cardiologists' opinions, SelfMED requires substantial time investment. In summary, SelfMED facilitated patient medication self-management in-hospital. As an essential step in the preparation for a full trial, this study showed it is feasible and safe to implement the intervention and identified some possibilities for refinement.

Home care nurses’ management of high-risk medications: a cross-sectional study

Background

High-risk medications use at home entails an increased risk of significant harm to the patient. While interventions and strategies to improve medications care have been implemented in hospitals, it remains unclear how this type of medications care is provided in the home care setting. The objective was to describe home care nurses’ management of high-risk medications.

Methods

A cross-sectional, descriptive design was set up in home care nurses in Flanders, Belgium. Participants were recruited through convenience sampling and could be included in the study if they provided medications care and worked as a home care nurses. Participants completed an online structured questionnaire. Questions were asked about demographic information, work experience, nurses’ general attitude regarding high-risk medications, contact with high-risk medications and the assessment of risk and severity of harm, specific initiatives undertaken to improve high-risk medications care and the use of additional measures when dealing with high-risk medications. Descriptive statistics were used.

Results

A total of 2283 home care nurses participated in this study. In our study, 98% of the nurses reported dealing high-risk medications. Home care nurses dealt the most with anticoagulants (96%), insulin (94%) and hypnotics and sedatives (87%). Most nurses took additional measures with high-risk medications in less than 25% of the cases, with the individual double check being the most performed measure for all high-risk medications except lithium. Nurses employed by an organization received support mostly in the form of a procedure while self-employed nurses mostly look for support through external organizations and information sources.

Conclusions

The study shows several gaps regarding high-risk medications care, which can imply safety risks. Implementation and evaluation of more standardized high-risk medications care, developing and implementing procedures or guidelines and providing continuous training for home care nurses are advised.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40545-022-00476-2.

Beliefs about medication after hospital discharge in geriatric patients with polypharmacy

OBJECTIVES

To describe beliefs about medication in geriatric patients with polypharmacy post-discharge and to evaluate the impact of discharge management on patients' medication beliefs.

METHODS

A cross-sectional study was conducted between November 2019 and March 2020 in twelve general hospitals in Belgium. Four hundred geriatric patients with polypharmacy were surveyed at hospital discharge and two to five days post-discharge using the Beliefs about Medicines Questionnaire and self-developed questionnaires.

RESULTS

According to participants, the benefits of medication outweighed the disadvantages as the mean necessity score (19.4/25) outweighed the mean concern score (11.9/25). Patients receiving help with medication management post-discharge had stronger necessity-, concern- and overuse-related beliefs. No patient- or discharge management-related factors were significant predictors of medication beliefs.

CONCLUSIONS

Assessing patients' medication beliefs and identifying and addressing patients' concerns, can be an opportunity to improve medication use, to prevent non-adherence and to enhance safe medication practices at home.

Nurses' responsibilities and tasks in pharmaceutical care: A scoping review

Aim

To provide an overview of responsibilities and tasks of nurses in pharmaceutical care.

Design

Scoping review.

Methods

Two databases were systematically searched (MEDLINE and Scopus) for recent original research papers concerning nurses’ responsibilities and tasks in pharmaceutical care. The definition of responsibility was based on literature, moral and ethical discussions. Existing responsibilities and tasks beyond preparation and administration of medication were collected and synthesized. This main study outcome was extracted from titles and abstracts only. Results were reported in accordance with PRISMA‐ScR guidelines.

Results

Of the 3,805 titles and abstracts reviewed, 453 abstracts were included. A total of seven responsibilities were identified: (a) management of therapeutic and adverse effects of medication, (b) management of medication adherence, (c) management of patient medication self‐management, (d) management of patient education and information about medication, (e) prescription management, (f) medication safety management and (g) (transition of) care coordination. Within these responsibilities, all tasks performed by nurses were described.

What Happens after Hospital Discharge? Deficiencies in Medication Management Encountered by Geriatric Patients with Polypharmacy

This study aimed to describe post-discharge medication self-management by geriatric patients with polypharmacy, to describe the problems encountered and to determine the related factors. In a multicenter study from November 2019 to March 2020, data were collected at hospital discharge and two to five days post-discharge. Geriatric patients with polypharmacy were questioned about medication management using a combination of validated (MedMaIDE) and self-developed questionnaires. Of 400 participants, 70% did self-manage medication post-discharge. Patients had a mean of four different deficiencies in post-discharge medication management (SD 2.17, range 0-10). Knowledge-related deficiencies were most common. The number of medicines and the in-hospital provision of medication management by nurses were significant predictors of post-discharge medication management deficiencies. In addition to deficiencies in knowledge, medication-taking ability and obtaining medication, non-adherence and disrupted continuity of medication self-management were common in geriatric patients with polypharmacy post-discharge. Improvements in in-hospital preparation could avoid medication self-management problems at home.

Effect of Solid-Meal Caloric Content on Gastric Emptying Kinetics of Solids and Liquids

In this study, we have evaluated the effect of the caloric content of a physiological test meal on the gastric emptying kinetics of solids and liquids. 22 healthy male volunteers were studied in two groups matched for age. After an overnight fast, each volunteer underwent the same test procedure; in the first group (G I), 10 volunteers received a meal consisting of bread,111In-DTPA water and 1 scrambled egg labeled with 99mTc-labelled sulphur colloid; in the second group (G II) 12 volunteers were given the same meal but with 2 labeled eggs in order to increase the caloric content of the solid phase meal. Simultaneous anterior and posterior images were recorded using a dualheaded gamma camera. Solid and liquid geometric mean data were analyzed to determine the lag phase, the emptying rate and the half-emptying time for both solids and liquids. Solid and liquid gastric half-emptying times were significantly prolonged in G II compared to G I volunteers. For the solid phased, the delay was accounted for by a longer lag phase and a decrease in the equilibrium emptying rate. The emptying rate of the liquid phase was significantly decreased in G II compared to G I. Within each group, no statistically significant difference was observed between solid and liquid emptying rates. We conclude that the caloric content of the solid portion of a meal not only alters the emptying of the solid phase but also affects the emptying of the liquid component of the meal.

Comparison of Quantification Methods of111In-Labelled Platelet Deposition in Peripheral Bypass Grafts

The action of antithrombotic drugs can be evaluated by measuring the deposition of111In-labelled platelets on peripheral bypass grafts several days after injection. This evaluation can be performed qualitatively (visual interpretation on the daily images) or quantitatively. Four different methods which calculate the ratio of platelet uptake with a reference region are compared: two methods use a gamma camera and two a detector. A blood sample or the region under the sternal angle are used as reference. The daily ratio of the counts, recorded by a gamma camera in a region of interest covering the graft, and the blood radioactivity interpolated from a platelet survival curve appears to be the most reliable method. The information of all the ratios can be combined in a single thrombogenicity index which reflects the daily rise of a linear or exponential regression versus time.

Pulmonary Tumor Microembolism

Pulmonary tumor embolism is an often missed antemortem diagnosis in patients with cancer and respiratory failure. Although rare, this complication is an important cause of additional morbidity. Referred for radionuclide pulmonary perfusion and ventilation scintigraphy, a typical pattern of multiple subsegmental peripheral defects on perfusion lung scanning without matching ventilation defects, suggesting a high probability for pulmonary thromboembolism, often leads to false conclusions.

We present a case of bilateral multiple subsegmental mismatched defects in lung ventilation perfusion scintigraphy, where autopsy confirmed the diagnosis of pulmonary tumor embolism, secondary to an undifferentiated ductal type adenocarcinoma of the pancreas. Pulmonary tumor embolism is an entity to keep in mind in patients treated for carcinoma presenting with (sub) acute dyspnea.

Comparison of diagnostic accuracy of (111)In-pentetreotide SPECT and (68)Ga-DOTATOC PET/CT: A lesion-by-lesion analysis in patients with metastatic neuroendocrine tumours

OBJECTIVES

To compare the diagnostic accuracy of (111)In-pentetreotide-scintigraphy with (68)Ga-DOTATOC-positron emission tomography (PET)/computed tomography (CT) in patients with metastatic-neuroendocrine tumour (NET) scheduled for peptide receptor radionuclide therapy (PRRT). Incremental lesions (ILs) were defined as lesions observed on only one modality.

METHODS

Fifty-three metastatic-NET-patients underwent (111)In-pentetreotide-scintigraphy (24 h post-injection; planar+single-photon emission CT (SPECT) abdomen) and whole-body (68)Ga-DOTATOC-PET/CT. SPECT and PET were compared in a lesion-by-lesion and organ-by-organ analysis, determining the total lesions and ILs for both modalities.

RESULTS

Significantly more lesions were detected on (68)Ga-DOTATOC-PET/CT versus (111)In-pentetreotide-scintigraphy. More specifically, we observed 1,098 lesions on PET/CT (range: 1-105; median: 15) versus 660 on SPECT (range: 0-73, median: 9) (p<0.0001), with 439 PET-ILs (42/53 patients) and one SPECT-IL (1/53 patients). The sensitivity for PET/CT was 99.9 % (95 % CI, 99.3-100.0), for SPECT 60.0 % (95 % CI, 48.5-70.2). The organ-by-organ analysis showed that the PET-ILs were most frequently visualized in liver and skeleton.

CONCLUSION

Ga-DOTATOC-PET/CT is superior for the detection of NET-metastases compared to (111)In-pentetreotide SPECT.

KEY POINTS

Somatostatin receptor PET is superior to SPECT in detecting NET metastases. PET is the scintigraphic method for accurate depiction of NET tumour burden. The sensitivity of PET is twofold higher than the sensitivity of SPECT.

Effect of creatine supplementation as a potential adjuvant therapy to exercise training in cardiac patients: a randomized controlled trial

OBJECTIVE

To investigate the effect of oral creatine supplementation in conjunction with an exercise programme on physical fitness in patients with coronary artery disease or chronic heart failure.

DESIGN

Single centre double-blind randomized placebo controlled trial.

SETTING

Cardiac rehabilitation centre.

SUBJECTS AND INTERVENTION

70 (4 women) cardiac patients (age 57.5 (8.4) years) were randomized to a placebo (n = 37) or creatine (n = 33) treatment for three months. Combined aerobic endurance and resistance training (three sessions/ week) was performed during supplementation.

MAIN MEASURES

Aerobic power was determined during graded bicycle testing, knee extensor peak isometric and isokinetic strength, endurance and recovery were assessed by an isokinetic dynamometer, and health related quality of life was evaluated with the SF-36 and MacNew Heart Disease questionnaires. In addition, blood samples were taken after an overnight fast and 24 hour urinary collection was performed.

RESULTS

At baseline there were no significant differences between both groups. We observed main time effects for aerobic power, muscle performance, health related quality of life, high density lipoprotein cholesterol and triglycerides (pre vs post; P<0.05 for all). However, changes after training were similar between placebo group and creatine group (P>0.05). Further, no detrimental effect on renal or liver function was observed nor were there any reports of side effects.

CONCLUSION

Oral creatine supplementation in combination with exercise training does not exert any additional effect on the improvement in physical performance, health related quality of life, lipid profile in patients with coronary artery disease or chronic heart failure than exercise training alone.

Molecular imaging of prostate cancer

Prostate carcinoma is the most common non-cutaneous malignancy in males. Imaging of prostatic lesions is of great importance and aids in oncologic management and monitoring of therapy response. Particularly molecular imaging based on positron emission tomography (PET) and single photon emission computerized tomography (SPECT) has great potential. Using radio-labelled molecular probes, these approaches are highly sensitive and can provide key molecular and functional information on tumours. The identification of suitable targets based on unique genetic and biochemical features of cancer lesions is one of the core activities driving progress in molecular imaging of pathological processes. Nowadays, mainly metabolic probes are being used routinely for detection and staging of prostate cancer. The development of new specific receptor ligands and targeted probes and antibodies holds great promise to further enhance the performance of molecular imaging and to further improve the diagnosis and monitoring of prostate cancer.

An unusual case of 4-aminopyridine toxicity in a multiple sclerosis patient: epileptic disorder or toxic encephalopathy?

We report the case of a 45-year old female multiple sclerosis patient, who accidentally was overdosed with 4-aminopyridine which resulted in dystonic, choreathetoid type abnormal movements in the four limbs, motoric distress, confusion and opisthotonus. There is little known about 4-aminopyridine toxicity. There are only a few reported cases ranging from mild paresthesias to tonic-clonic seizures. 4-aminopyridine enhances neuronal conduction at neuromuscular synapses and is indicated in the treatment of selected neurological disorders including multiple sclerosis (MS) and myasthenia gravis, among others.

Non-Hodgkin lymphoma: retrospective study on the cost-effectiveness of early treatment response assessment by FDG-PET

PURPOSE

Although lymphomas are very chemosensitive, 50% of patients with aggressive non-Hodgkin lymphoma (NHL) are not cured with standard first-line treatment. This consists of six cycles of doxorubicin, vincristine, prednisolone and cyclophosphamide (CHOP), recently complemented with rituximab. Preliminary studies show that PET mid-treatment is a good predictor of the remission status at the end of therapy. As patients with persistent FDG uptake after three cycles are unlikely to gain a complete remission, the remaining three cycles of chemotherapy are useless. We investigated the costs and benefits for the use of PET in this early treatment setting.

METHODS

We conceived a model using a conventional arm where patients receive the full regimen of six cycles of CHOP [-rituximab] and an experimental algorithm where patients receive either six cycles (PET response) or only three cycles (PET non-response). Based on a patient sample (2004-2006), we calculated the costs for hospitalisation and treatment. We took into account all costs accrued (including overhead costs). We used a sensitivity analysis by varying the most important parameters.

RESULTS

With a PET price of 700 euro and CHOP price (per cycle) of 1,829 euro , we can conclude to cost saving of 1,879 euro per patient. The PET price can increase up to 2,580 euro and the cost for one cycle of CHOP can decrease to 500 euro per cycle before cost savings are nil. The percentage of non-responders may be as low as 10%. The implementation of rituximab in first-line therapy only increases benefit (4,900 euro/pt).

CONCLUSION

We conclude to substantial cost savings if management of NHL patients is based on mid-treatment PET scan. The economical data we used seem to be comparable to those published in other European studies. Implementation of Mabthera in first line only increases cost savings.

Synthesis and evaluation of a 99mTc-BAT-phenylbenzothiazole conjugate as a potential in vivo tracer for visualization of amyloid β

We have conjugated S,S'-bis-trityl-N-BOC-N'-acetic acid-1,2-ethylenedicysteamine, a protected bis-amino-bis-thiol (BAT) tetraligand, with 2-(4'-aminophenyl)-1,3-benzothiazole, a derivative of thioflavin-T with known affinity for amyloid. The conjugate was efficiently labelled with (99m)Tc by heating of the protected precursor in diluted hydrochloric acid followed by neutralization and heating in the presence of (99m)Tc-tartrate. It was demonstrated that the (99m)Tc-BAT-phenylbenzothiazole conjugate binds in vitro to amyloid beta present in postmortem brain slices of Alzheimer's patients. Despite its high lipophilicity and neutral character, the radiolabelled conjugate did not cross the blood-brain barrier to a sufficient degree and therefore is not useful for detection of Alzheimer's disease. Further evaluation of this (99m)Tc-labelled tracer agent could elucidate its potential usefulness to visualize amyloid plaques in peripheral amyloidosis.

Takayasu's arteritis in a young Caucasian female: case report and review

We report a case of a 24-year-old Caucasian woman presenting with fatigue, weight loss, a cardiac murmur, anaemia and biochemical markers of inflammation due to Takayasu's arteritis (TA), a vasculitis of the aorta and large vessels that typically affects young women. The rarity of the disease, the great variability in presentation together with the absence of specific symptoms as well as the absence of specific biochemical markers, makes early diagnosis difficult. Besides (magnetic resonance) arteriography, new promising diagnostic tools are discussed, including transoesophageat echocardiography (TEE) and Positron Emission Tomography (PET). Nevertheless, a high index of suspicion remains the key to an early diagnosis, and hence a better prognosis, of TA.

Repetitive 18-fluorodeoxyglucose positron emission tomography in isolated polymyalgia rheumatica: a prospective study in 35 patients

OBJECTIVE

To study fluorodeoxyglucose (FDG) deposition in different vascular beds and in the large joints of patients with isolated polymyalgia rheumatica (PMR), and to investigate whether there is a relation between FDG-positron emission tomography (PET) results and risk of relapse.

METHODS

All consecutive patients with isolated PMR underwent a FDG-PET scan before treatment with steroids was started and--if logistics allowed--at 3 and 6 months. PET scans were scored at seven different vascular areas and a total vascular score (TVS) was calculated, ranging from 0 to 21. FDG uptake in the shoulders, the hips and the processi spinosi of the vertebrae was scored as 0 (no uptake), 1 (moderate uptake) or 2 (intense uptake).

RESULTS

Thirty-five patients entered the study. At diagnosis, vascular FDG uptake was noted in 11 patients (31%), predominantly at the subclavian arteries. Mean TVS was low. FDG uptake in the shoulders was noted in 94% of patients, in the hips in 89% and in the processi spinosi of the vertebrae in 51%. The intensity of FDG uptake in the large vessels or in the shoulders, hips or processi spinosi did not correlate with the risk of relapse.

CONCLUSIONS

Only one in three patients has an (moderately) increased vascular FDG uptake, especially in the subclavian arteries. The vast majority has inflammation of shoulders and hips, and half of them have increased FDG-uptake at the processi spinosi. Results of FDG-PET scans in patients with PMR did not correlate with their risk of relapse.

[11C]methionine PET, histopathology, and survival in primary brain tumors and recurrence

BACKGROUND AND PURPOSE

[(11)C]Methionine (MET) PET imaging is a sensitive technique for visualizing primary brain tumors and recurrence/progression after therapy. The aim of this study was to evaluate the relationship between the uptake of MET and histopathologic grading and to investigate the prognostic value of the tracer, in both settings.

METHODS

Cerebral uptake of MET was determined in 52 patients: in 26 patients for primary staging (group A) and 26 patients with suspected brain tumor recurrence/progression after therapy (group B). Semiquantitative methionine uptake indices (UI) defined by the tumor (maximum)-to-background ratio was correlated with tumor grade and final outcome.

RESULTS

Overall median survival was 34.9 months. MET showed pathologically increased uptake in 41 of 52 scans. Although a weak linear correlation between MET uptake and grading was observed (R = 0.38, P = .028), analysis of variance showed no significant differences in MET UI between tumor grades for either group A or B. Benign and grade I lesions showed significant difference in MET uptake in comparison with higher grade lesions (P = .006). Using Kaplan-Meier survival analysis, no thresholds could be found at which MET was predictive for survival. Proportional hazard regression showed that only WHO grading class (low versus high) was predictive of survival (P = .015).

CONCLUSION

Interindividual MET uptake variability does not allow noninvasive grading on an individual patient basis. Moreover, there is no significant prognostic value in studying maximal methionine UI in brain tumors. The clinical use of MET should therefore be primarily focused on questions such as detection of recurrence, biopsy guidance, and radiation therapy target volume delineation.

Additional value of PET-CT in the staging of lung cancer: comparison with CT alone, PET alone and visual correlation of PET and CT

Integrated positron emission tomography (PET) and computed tomography (CT) is a new imaging modality offering anatomic and metabolic information. The purpose was to evaluate retrospectively the accuracy of integrated PET-CT in the staging of a suggestive lung lesion, comparing this with the accuracy of CT alone, PET alone and visually correlated PET-CT. Fifty patients undergoing integrated PET-CT for staging of a suggestive lung lesion were studied. Their tumor, node, metastasis (TNM) statuses were determined with CT, PET, visually correlated PET-CT and integrated PET-CT. These TNM stages were compared with the surgical TNM status. Integrated PET-CT was the most accurate imaging technique in the assessment of the TNM status. Integrated PET-CT predicted correctly the T status, N status, M status and TNM status in, respectively, 86%, 80%, 98%, 70% versus 68%, 66%,88%, 46% with CT, 46%, 70%, 96%, 30% with PET and 72%, 68%, 96%, 54% with visually correlated PET-CT. T status and N status were overstaged, respectively, in 8% and 16% with integrated PET-CT, in 20% and 28% with CT, in 16% and 20% with PET, in 12% and 20% with visually correlated PET-CT and understaged in 6% and 4% with integrated PET-CT, versus 12% and 6% with CT, 38% and 10% with PET and 12% with visually correlated PET-CT. Integrated PET-CT improves the staging of lung cancer through a better anatomic localization and characterization of lesions and is superior to CT alone and PET alone. If this technique is not available, visual correlation of PET and CT can be a valuable alternative.

FDG-PET for preoperative staging of bladder cancer

PURPOSE

The presence of lymph node involvement (N) and distant metastasis (M) in patients with invasive bladder carcinoma is a major determinant of survival and, therefore, a pivotal element in the therapeutic management. The aim of this prospective study was to evaluate the use of( 18)F-fluorodeoxyglucose positron emission tomography (FDG-PET) in this indication.

METHODS

Whole-body FDG-PET and computed tomography (CT) were performed in 55 patients with non-metastatic invasive bladder cancer for preoperative staging. Correlative imaging of PET with CT was performed, leading to a PET(CT) result. The imaging results were compared with the gold standard, consisting of histopathology (lymphadenectomy, guided biopsy) or clinical follow-up for 12 months, and related to overall survival using the Kaplan-Meier method.

RESULTS

The gold standard was available in 40 patients and indicated NM-positive disease in 15 patients (12 N lesions, 8 M lesions), and NM-negative disease in 25 patients. For the diagnosis of NM-positive disease, the sensitivity, specificity and accuracy of PET(CT) were 60%, 88% and 78%, respectively. Diagnostic discordances between PET(CT) and CT alone were found in 9/40 patients, among whom PET was correct in six (15%): three with true-positive and one with true-negative distant metastases, and two with true-negative lymph nodes. Median survival time of patients in whom PET(CT) indicated NM-positive disease was 13.5 months, compared with 32.0 months in the patients with a NM-negative PET(CT) (p=0.003).

CONCLUSION

Addition of metabolism-based information provided by FDG-PET to CT in the preoperative staging of invasive bladder carcinoma yields a high diagnostic and prognostic accuracy.

Mucociliary transport using 99mTc-albumin colloid: a reliable screening test for primary ciliary dyskinesia

BACKGROUND

A study was undertaken to assess the reliability of the nasal mucociliary transport test using 99mTc-albumin colloid as a screening test for primary ciliary dyskinesia (PCD) and to compare it with the gold standard nasal biopsy for study of ciliary motility and ultrastructure.

METHODS

During a 4 year period both tests were performed in 55 children referred with persistent or recurrent respiratory tract infections. Their median age was 4 years (range 1 month to 15 years).

RESULTS

The nasal biopsy results were as follows: PCD, n = 8; secondary ciliary dyskinesia (SCD), n = 19; normal, n = 28. The mucociliary transport test was abnormal in 29 patients (all 8 with PCD, 7/19 with SCD, and 14/28 with a normal biopsy). The sensitivity of the mucociliary transport test to diagnose PCD was therefore 100% (8/8) (95% exact confidence limits 63.06 to 100.00); the specificity was only 55% (26/47) (40.95 to 69.89). The negative predictive value was 100% (26/26) (86.77 to 100.00) and the positive predictive value was 28% (8/29) (12.37 to 47.24).

CONCLUSION

Mucociliary transport is a non-invasive screening test that can be performed even in infants. The sensitivity of the test is high but its specificity is low. A normal test result excludes PCD.

Cost-effectiveness of 18F-fluorodeoxyglucose positron emission tomography in the assessment of early dementia from a Belgian and European perspective

(18)F-fluoro-deoxyglucose positron emission tomography (FDG PET) can aid to predict AD in an early stage. The aim of this study was to estimate the economic effects of incorporating FDG PET in the diagnostic work-up of AD in a Belgian and European setting. A decision tree analysis was followed comparing a conventional algorithm using diagnostic clinical criteria and one that also incorporates PET. Major outcome terms were overall cost per patient in either strategy; diagnostic accuracy and cost per accurate diagnosis. A sensitivity analysis was performed for four critical variables: cost of PET, sensitivity and specificity of PET and delay in cognitive decline because of appropriate medication. Cost-savings per accurate diagnosis ranged from 623-6110 Euro in favour of the proposed algorithm with PET. For the same cost, more accurate diagnoses were made, resulting in benefit for patients and society. The positive results were maintained over a wide range of values for the critical variables and were expandable to other European countries with a similar health system. Therefore, incorporation of FDG PET into the clinical diagnostic work up of patients with early symptoms of cognitive decline can be advocated.

Evaluation of hypoxia in an experimental rat tumour model by [(18)F]fluoromisonidazole PET and immunohistochemistry

This study aimed to evaluate tumour hypoxia by comparing [¹⁸F]Fluoromisonidazole uptake measured using positron emission tomography ([¹⁸F]FMISO-PET) with immunohistochemical (IHC) staining techniques. Syngeneic rhabdomyosarcoma (R1) tumour pieces were transplanted subcutaneously in the flanks of WAG/Rij rats. Tumours were analysed at volumes between 0.9 and 7.3 cm³. Hypoxic volumes were defined using a 3D region of interest on 2 h postinjection [¹⁸F]FMISO-PET images, applying different thresholds (1.2–3.0). Monoclonal antibodies to pimonidazole (PIMO) and carbonic anhydrase IX (CA IX), exogenous and endogenous markers of hypoxia, respectively, were used for IHC staining. Marker-positive fractions were microscopically measured for each tumour, and hypoxic volumes were calculated. A heterogeneous distribution of hypoxia was observed both with histology and [¹⁸F]FMISO autoradiography. A statistically significant correlation (P<0.05) was obtained between the hypoxic volumes defined with [¹⁸F]FMISO-PET and the volumes derived from the PIMO-stained tumour sections (r=0.9066; P=0.0001), regardless of the selected threshold between 1.4 and 2.2. A similar observation was made with the CA IX staining (r=0.8636; P=0.0006). The relationship found between [¹⁸F]FMISO-PET and PIMO- and additionally CA IX-derived hypoxic volumes in rat rhabdomyosarcomas indicates the value of the noninvasive imaging method to measure hypoxia in whole tumours.

Position of positron emission tomography and other imaging diagnostic modalities in esophageal cancer

Positron emission tomography (PET) using the positron emitting glucose analogue 18F-fluorodeoxyglucose (FDG) has emerged as a useful metabolism-based wholebody imaging tool for gastro-esophageal cancer diagnosis and follow up. Most large cancer centers worldwide are now equipped for PET (or even PET-CT). Therefore, there is a growing need for a clear definition of the relative position of PET within the currently available diagnostic modalities. Significant scientific data indicate that FDG-PET adds clinically useful information to the information obtained by standard means (mainly CT and endoscopic ultrasound) throughout the different phases of clinical patient management: 1) at initial diagnosis: PET detects more frequently distant lymph node involvement and organ metastases compared to conventional diagnostics, allowing a more accurate selection of the most appropriate treatment; 2) during chemotherapy: semi-quantitative FDG-PET allows early identification of non-responding patients. Indeed, the metabolic response as measured by serial FDG-PET can be used to predict the clinical and histopathological response. Moreover, the PET-response seems to be related to overall and disease free survival; 3) after a treatment: FDG-PET allows accurate assessment of the residual tumor load; 4) in the follow up: FDG-PET allows accurate detection and restaging of recurrent disease.

Quantifying myocardial deformation throughout the cardiac cycle: a comparison of ultrasound strain rate, grey-scale M-mode and magnetic resonance imaging

Strain rate imaging (SRI) is a new ultrasound (US) approach to the quantification of regional myocardial deformation. It previously has been validated in vitro and in vivo against other imaging techniques. However, in all such studies, only peak strain values were compared, and the temporal evolution of the strain curve was not studied. Yet, it is the temporal evolution of the strain curves that contains the more important clinical information (e.g., asynchrony, viability, etc). Thus, the aim of this study was to compare the evolution of strain during the complete cardiac cycle as measured by US SRI, US grey-scale M-mode and magnetic resonance imaging (MRI). In 10 healthy volunteers and 20 patients with chronic ischaemic heart disease, radial deformation of the inferolateral segment of the left ventricle was measured by US SRI, US M-mode and MRI. The correspondence of the temporal characteristics of these strain curves were compared by defining an intraclass correlation coefficient (ICC). In healthy volunteers, an overall good agreement (mean ICC: 0.75 and 0.63 for systole and diastole) was found between the different methods. However, in patients with abnormal segmental deformation and low peak strain values, the agreement was less (mean ICC: 0.42 and 0.32), but remained within acceptable limits for clinical decision making. Myocardial deformation measurements using SRI correlated well with MRI and US M-mode measurements throughout the complete cardiac cycle.

Dopamine transporter SPECT using fast kinetic ligands: 123I-FP-beta-CIT versus 99mTc-TRODAT-1

A comparative study was carried out on two promising presynaptic dopamine transporter single-photon emission tomography (SPECT) radioligands with a fast pharmacokinetic profile, 123I-FP-beta-CIT (FP) and 99mTc-TRODAT-1 (TR), in order to assess their differential diagnostic power in early parkinsonism and their sensitivity for detection of disease progression. This cross-sectional study was conducted on 96 patients with early-stage parkinsonism referred in a tertiary clinical setting. Mean disease duration was 2.0+/-1.3 years, and patients had a modified Hoehn and Yahr (H&Y) stage of 1-2 (average 1.2). Forty-seven patients received TR, and 49 received FP. In both groups, ten patients with normal presynaptic function were included as a control population; all other patients were clinically diagnosed as having idiopathic Parkinson's disease. Groups were matched for gender, age, disease duration and modified H&Y stage. Triple-head gamma camera SPECT was analysed using a semiquantitative index of transporter binding (BI). Discriminant analysis with cross-validation resulted in a maximal classification accuracy for FP of 93% (sensitivity 95% and specificity 86%) for the contralateral putamen BI. For TR, the corresponding values were 87% accuracy, 92% sensitivity and 70% specificity. For FP, disease duration was correlated with both the putamen BI (-8.8%/year, rho=-0.41, P=0.025) and the putamen/caudate ratio (-7.4%/year, rho=-0.51, P=0.004), but for TR no significant correlation was found (all P values >0.5). In conclusion, both FP and TR show high sensitivity in a clinically relevant setting, but FP has superior accuracy for early differential diagnosis of idiopathic parkinsonism and non-degenerative extrapyramidal disorders, as well as better sensitivity for disease follow-up.

Positron emission tomography with FDG in the detection of peritoneal and retroperitoneal metastases of ovarian cancer

OBJECTIVE

The aim of this prospective study was to evaluate (18)F-FDG-PET, in comparison with CT, for the detection of peritoneal and retroperitoneal metastases of ovarian cancer.

METHODOLOGY

13 patients with primary (n = 7) or recurrent (n = 6) ovarian cancer underwent an attenuation-corrected (18)F-FDG-PET of the abdomen as well as a contrast-enhanced abdominal CT, followed by surgical staging. For data analysis, the abdomen was artificially divided into six regions (right and left subphrenic region, right and left paracolic gutter, retroperitoneum and central abdomen). All images were reviewed and each region was visually scored on (18)F-FDG-PET as well as on CT. (18)F-FDG-PET results were compared with those of CT, using the surgical data as gold standard.

RESULTS

73 regions were evaluable surgically and or histologically. Sensitivity was slightly better for CT than for (18)F-FDG-PET (74 vs. 66%). Metastases of <5 mm were missed with both techniques. Specificity, however, was clearly better for (18)F-FDG-PET than for CT (94 vs. 77%), especially in patients with recurrent disease, where postoperative changes (hematomas, adhesions, etc.) caused more false positive results on CT. Retroperitoneal lymph node involvement was found in 3/13 patients. The result of (18)F-FDG-PET for the retroperitoneal lymph nodes was correct in all cases, whereas CT was false positive in 2 patients. (18)F-FDG-PET is relatively inaccurate for the right and the left subphrenic region (missing tumor involvement in 5 patients compared to 2 patients for CT).

CONCLUSION

Given the low sensitivity of both (18)F-FDG-PET and CT for the detection of peritoneal metastases, surgical staging remains the gold standard. Because of the better specificity, (18)F-FDG-PET might be preferred for evaluating residual or recurrent disease after surgery. (18)F-FDG-PET was more sensitive in the retroperitoneal region than intraperitoneal.

18FDG-Positron emission tomography for the early prediction of response in advanced soft tissue sarcoma treated with imatinib mesylate (Glivec)

Imatinib mesylate (Glivec, formerly STI571) is the first effective systemic treatment for gastrointestinal stromal tumours (GISTs). Major changes in tumour volume, however, tend to occur late after the start of treatment. The aim of this study was to evaluate if [18F]-fluorodeoxyglucose-positron emission tomography (FDG-PET) can be used for the early evaluation of response to imatinib mesylate treatment in soft-tissue sarcomas (STS). 21 patients (17 GIST, 4 other STS) underwent FDG-PET imaging prior to and 8 days after the start of treatment. PET response (European Organization for Research and Treatment (EORTC) guidelines) was observed in 13 GISTs (11 Complete Responders, 2 partial responders. Subsequent computerised tomography (CT) response Response Evaluation Criteria in Solid Tumours (RECIST) was observed in 10 of these patients after a median follow up of 8 weeks. Stable or progressive disease was observed on PET in 8 patients and none of them achieved a response on CT. PET response was also associated with a longer progression-free survival (PFS) (92% versus 12% at 1 year, P=0.00107). We conclude that FDG-PET is an early and sensitive method to evaluate an early response to imatinib treatment.

An efficient HPLC method for the analysis of isomeric purity of technetium-99m-exametazime and identity confirmation using LC-MS

99mTc-exametazime (99mTc-d,l-HMPAO, 99mTc-d,l-hexamethylpropyleneamine oxime) is a neutral rather unstable complex of short-lived 99mTc (t(1/2)=6 h) with the d,l-isomer (mixture of D,D- and L,L-isomers) of a bis-amine bis-oxime tetraligand. It is widely used for measurement of regional cerebral perfusion in nuclear medicine. The meso-isomer (D,L-form) should not be present in a preparation as it is not retained in brain and thus does not provide clinically useful information. Meso-HMPAO is removed from the ligand during the synthesis procedure by repeated recrystallization, but can still be present as impurity in d,l-isomer. Due to the lack of a suitable chromatographic method for analysis of the isomeric purity of 99mTc-exametazime preparations, United States Pharmacopoeia 25 (USP 25) prescribes a biological test in rats for quality control purpose. In this study, we developed a suitable high-performance liquid chromatography (HPLC) method which allows to demonstrate the relative amounts of d,l- and meso-isomer in 99mTc-exametazime and so obviates the need for a biodistribution test in animals as part of the quality control. Due to the low concentrations in which 99mTc-d,l-HMPAO is obtained (typically 2-6 ng/ml), confirmation of the identity of 99mTc-d,l-HMPAO in the monograph of the European Pharmacopoeia is now performed only indirectly by TLC and assessment of its retention time on RP-HPLC. To investigate the potential of radio-LC-MS for assessment of the identity of 99mTc-exametazime, 99mTc-d,l-HMPAO and 99mTc-meso-HMPAO prepared using a Tc-rich eluate were analyzed using a radio-LC-MS system equipped with a time-of-flight mass spectrometer with electrospray ionization. The main peak in the radiometric channel coincided with the molecular ion mass of 99mTc-d,l-HMPAO in the mass spectrometer channel and the measured accurate mass differed only by 0.26 ppm from the theoretical mass. The identity of 99mTc-meso-HMPAO was also confirmed. Thus, radio-LC-MS allowed to obtain strong evidence for the structure of 99mTc-d,l-HMPAO and 99mTc-meso-HMPAO at nanomolar concentration. It is concluded that radio-LC-MS can become a sensitive aid in quality control of "no carrier added" radiopharmaceutical preparations.

An outbreak of Legionnaire's disease among visitors to a fair in Belgium in 1999

This paper describes an outbreak of Legionnaire's disease at Kapellen in Belgium among visitors of the annual fair. The investigation started on 13th November 1999 after a respiratory physician notified the health authorities of the province of Antwerp of presumptive cases of legionellosis. The annual commercial fair at Kapellen, a small town in northern Belgium, was held 10 days previously and attracted 50,000 visitors. Stand employees (professionals or volunteers), technical staff of the hall and visitors at the fair were affected cases. An exploratory case-control study was conducted to trace the source of the epidemic. To complete the inventory study and to evaluate other risk factors, a cohort study of exhibitors and staff was conducted. Ninety-three people met the case definition, 41 of whom were considered as confirmed, 14 as presumptive cases and 38 as possible/clinical cases. Five people died. Further testing at the reference laboratory confirmed all strains to be Legionella pneumophila serogroup 1. The sensitivity for culture was low (29.2%), and sensitivity for seroconversion was high (90.9%). For urinary antigen test, a sensitivity with Biotest EIA of 65.6% was found, and the sensitivity of polymerase chain reaction (PCR) was 85.7%. In all cases, the individual had visited the fair. Those individuals working in the central areas of the tent, near the aerosol-producing devices, were at higher risk of disease. Legionella was detected by PCR on swabs of the surfaces of the whirlpool. Although not fully proven, an aerosol-producing device was the most probable source of the outbreak.

The potential value of ultrasonic deformation measurement in differentiating regional ischaemic substrates during dobutamine stress echocardiography

The differentiation between differing regional ischaemic substrates is crucial for decision-making in patients with coronary artery disease. This study demonstrates that quantification of dobutamine stress echocardiography using ultrasonic strain measurement has the potential to identify three differing regional ischaemic substrates (ischaemic, stunned and scarred) in the same patient. The data were validated by traditional analysis of dobutamine stress echo, coronary angiography and correlative quantitative positron emission tomography information.

Assessment of myocardial viability in a porcine model of chronic coronary artery stenosis with dual dose dobutamine magnetic resonance imaging

In a non-surgical porcine coronary stenosis model resulting in chronic left ventricle dysfunction, we aimed in this study to evaluate the potential of magnetic resonance imaging (MRI) to distinguish dysfunctional but viable from necrotic myocardium by using multiple levels of dobutamine inotropic stimulation during a cine MRI protocol (F.P. van Rugge et al. Circulation 1994; 90: 127-138). We compared our results with histopathology. We were able to demonstrate a biphasic effect at increasing doses of dobutamine in a subgroup of animals with a high-grade coronary stenosis, while in another subgroup the coronary stenosis produced a chronic myocardial infarction, in which no functional recovery could be obtained. In this experimental protocol, dual dose dobutamine MRI proved to be an accurate and reproducible technique to perform viability studies in chronic obstructive coronary artery disease. It permits distinguishing chronic ischemic, but viable myocardium from infarcted tissue. The detection of chronically underperfused but potentially salvageable myocardium is of significant clinical importance since it may aid in determining which patients are eligible for revascularization.