Adenosine coronary vasodilation quantitative technetium 99m methoxy isobutyl isonitrile myocardial tomography in the identification and localization of coronary artery disease

Background

Exercise and dipyridamole ^99mTc-labeled methoxy isobutyl isonitrile (MIBI) myocardial scintigraphy have been widely used for the diagnosis of coronary artery disease (CAD). However, only limited data on adenosine ^99mTc-labeled MIBI cardiac imaging are currently available. This study was designed to assess the accuracy of quantitative adenosinerest ^99mTc-labeled MIBI tomography in the diagnosis and localization of CAD.

Methods and Results

Fifty-seven consecutive patients with suspected CAD who underwent coronary angiography and 22 normal volunteers were studied. All patients underwent ^99mTc-labeled MIBI tomography after administration of adenosine (140 μg/kg intravenously for 6 minutes) and at rest. A total of 171 vascular coronary territories were analyzed quantitatively. All patients with CAD (≥50% luminal stenosis) (n=55) had abnormal ^99mTc-labeled MIBI tomograms. The normalcy rate was 86% by quantitative analysis. Overall sensitivity, specificity, and diagnostic accuracy for detection of individual stenosed vessels were 84%, 87%, and 85%, respectively. In patients with one-vessel CAD (n=24), sensitivity and diagnostic accuracy in the detection of individual stenosed vessels were significantly (p<0.05) higher compared with patients with multivessel CAD (n=31). Moreover, 75% of patients with one-vessel disease showed a scintigraphic pattern characterized by the presence of perfusion defects in only one coronary artery territory, and 74% of patients with multivessel disease showed a scintigraphic pattern characterized by the presence of perfusion defects in two or more coronary artery territories. Sensitivity, specificity, and diagnostic accuracy for detecting individual diseased vessels were similar in patients without previous myocardial infarction (n=18) compared with those with previous myocardial infarction (n=39). In myocardial territories related to noninfarcted areas (n=124), sensitivity and specificity in the detection of stenosed vessels were 75% and 88%. In infarcted areas (n=47), sensitivity and specificity in the detection of stenosed vessels were 98% and 80% (differences not significant vs noninfarcted areas).

Conclusions

Adenosine-controlled coronary vasodilation combined with quantitative ^99mTc-labeled MIBI tomography is accurate for identifying patients with CAD and localizing individual stenosed coronary arteries.     

Quantitative exercise technetium-99m tetrofosmin myocardial tomography for the identification and localization of coronary artery disease

The aim of this study was to evaluate the accuracy of quantitative 1-day exercise-rest technetium-99m tetrofosmin tomography in the identification of patients with coronary artery disease (CAD) and in the detection of individual stenosed coronary vessels. Sixty-one patients with suspected CAD who underwent coronary angiography and 13 normal volunteers were studied. All patients were submitted to two i.v. injections of^99mTc-tetrofosmin, one at peak exercise (370 MBq) and the other (1110 MBq) at rest 3 h after exercise (images 15–30 min after injection for both studies). All patients with CAD (0% luminal stenosis) (n=50) had an abnormal^99mTc-tetrofosmin tomogram. Only one patient without significant coronary narrowing showed abnormal findings. Overall sensitivity, specificity and diagnostic accuracy in the detection of individual stenosed vessels were 77%, 93% and 85%, respectively. Sensitivity and diagnostic accuracy in the identification of individuals stenosed coronary vessels were significantly higher (P<0.05) in patients with single-vessel disease (n=21) than in those with multivessel disease (n=29). Sensitivity, specificity and accuracy for detecting individual diseased vessels were similar in patients without previous myocardial infarction (n=26) and in those with previous myocardial infarction (n=35). In myocardial territories related to non-infarcted areas (n=128), sensitivity and specificity in the detection of stenosed vessels were 70% and 95%, respectively. In infarcted areas (n=55), sensitivity and specificity in the detection of stenosed vessels were 85% (P=NS vs non-infarcted areas) and 75% (P<0.05 vs non-infarcted areas), respectively. Finally, sensitivity was significantly lower (P<0.05) in vascular territories supplied by vessels with moderate stenosis (50%–75%) than in those supplied by vessels with severe stenosis (>75%). The results of this study demonstrate that quantitative 1-day exercise-rest^99mTc-tetrofosmin single-photon emission tomographic imaging is a suitable and accurate technique to identify patients with CAD and to detect individual stenosed coronary vessels.     

Left ventricular diastolic function in type 2 diabetes mellitus is associated with myocardial triglyceride content but not with impaired myocardial perfusion reserve

Purpose:

To study myocardial perfusion reserve and myocellular metabolic alterations indicated by triglyceride content as possible causes of diastolic dysfunction in patients with type 2 diabetes mellitus, preserved systolic function, and without clinically evident coronary artery disease.

Materials and Methods:

Patients with type 2 diabetes mellitus (n = 42) underwent cardiac magnetic resonance (CMR) for quantification of 1) myocardial contractility by strain‐encoded MR (SENC); 2) myocardial triglyceride content by proton magnetic resonance spectroscopy (¹H‐MRS); and 3) myocardial perfusion reserve during pharmacologic hyperemia. Age‐matched healthy volunteers (n = 16) also underwent CMR to acquire normal values for myocardial strain and perfusion reserve.

Results:

Stress CMR procedures were successfully performed in all subjects, and no regional inducible perfusion defects were observed in type 2 diabetes mellitus patients. Diastolic strain rate and myocardial perfusion reserve were significantly impaired in patients with type 2 diabetes mellitus compared to control subjects (P < 0.001 for both). Interestingly, impaired diastolic function in type 2 diabetes mellitus was not associated with impaired myocardial perfusion reserve (r = 0.12, P = NS). Conversely a significant association was observed between diastolic dysfunction and myocardial triglyceride content (r = ?0.71, P < 0.001), which proved to be independent of age, gender, diabetes duration, blood pressure, and fasting blood glucose.

Conclusion:

Myocardial steatosis may represent an early marker of diabetic heart disease, triggering subclinical myocardial dysfunction irrespective of myocardial perfusion reserve. J. Magn. Reson. Imaging 2012;35:804–811. © 2011 Wiley Periodicals, Inc.

     

Ultrasound-Guided Radiological Placement of Central Venous Port via the Subclavian Vein: A Retrospective Analysis of 500 Cases at a Single Institute

The purpose of this study was to assess the technical success rate and adverse events (AEs) associated with ultrasound (US)-guided radiological placement (RP) of a central venous port (CVP) via the subclavian vein (SCV). Between April 2006 and May 2007, a total of 500 US-guided RPs of a CVP via the SCV were scheduled in 486 cancer patients (mean age ± SD, 54.1 ± 18.1 years) at our institute. Referring to the interventional radiology report database and patients’ records, technical success rate and AEs relevant to CVP placement were evaluated retrospectively. The technical success rate was 98.6% (493/500). AEs occurred in 26 cases (5.2%) during follow-up (range, 1–1080 days; mean ± SD, 304.0 ± 292.1 days). AEs within 24 h postprocedure occurred in five patients: pneumothorax (n = 2), arterial puncture (n = 1), hematoma formation at the pocket site (n = 2), and catheter tip migration into the internal mammary vein (n = 1). There were seven early AEs: hematoma formation at the pocket site (n = 2), fibrin sheath formation around the indwelling catheter (n = 2), and catheter-related infections (n = 3). There were 13 delayed AEs: catheter-related infections (n = 7), catheter detachments (n = 3), catheter occlusion (n = 1), symptomatic thrombus in the SCV (n = 1), and catheter migration (n = 1). No major AEs, such as procedure-related death, air embolism, or events requiring surgical intervention, were observed. In conclusion, US-guided RP of a CVP via the SCV is highly appropriate, based on its high technical success rate and the limited number of AEs.     

Hepatic arterial resistance index - An indicator of diffuse liver disease in children treated with bone marrow transplantation

Aim:

To describe the relationship between the resistance index of the common hepatic artery and liver function tests in children undergoing bone marrow transplantation.

Materials and Methods:

We analysed prospectively the results of 106 Doppler ultrasound examinations of the common hepatic artery from 31 bone marrow transplant patients, 16 of whom had normal liver function. The aetiology of the liver dysfunction in the other 15 patients was veno-occlusive disease (n=7), unknown (n=3), hepatic graft-versus-host disease (n=2), hepatitis (n=2), or cholestasis (n=1). We assessed the relationships between the hepatic arterial resistance index (HART) and the results of the serum glutamic-oxaloacetic transmainase (SGOT), serum glutamic-pyruvic transaminase (SGPT), alkaline phosphatase (ALK), lactate dehydrogenase (LDH) and serum albumin (ALB) assays and calculated HARI break-point values that might distinguish patients with liver disease from patients with the normal liver function.

Results:

The significant break point (P<0.05) of the HARI was 0.55 for SGOT, SGPT and ALK. LDH was associated with a break point of 0.53. Resistance indices for the common hepatic artery below the break-point values predicted liver dysfunction with specificities of 81%, 80%, 92% and 93%, respectively. There was no significant relationship between liver function tests and ALB levels.

Conclusion:

If below 0.55, the hepatic arterial resistance index is a non-invasive indicator of liver dysfunction in children undergoing bone marrow transplantation.     

Impaired renal function is a major determinant of left ventricular diastolic dysfunction: assessment by stress myocardial perfusion imaging

Objective

Relationships between myocardial scintigraphic parameters and renal function have not been fully determined. We investigated correlations between estimated glomerular filtration rate (eGFR) and left ventricular (LV) diastolic function using stress electrocardiographic (ECG)-gated myocardial single photon emission computed tomography (SPECT).

Methods

We enrolled 136 consecutive patients with suspected coronary artery disease (CAD) who were assessed using technetium-99m stress ECG-gated myocardial SPECT. We evaluated SPECT images using 17-segment defect scores graded on a 5-point scale, summed stress score, summed rest score and summed difference score (SDS). The parameters for assessing LV diastolic function were peak filling rate (PFR), 1/3 mean filling rate and time to peak filling. The CAD was defined as SDS ≥2. Chronic kidney disease (CKD) was defined as eGFR <60 mL/min/1.73 m². Patients were assigned to the following four groups (no CAD/no CKD: control group, n = 68; CAD/no CKD: CAD group, n = 24; no CAD/CKD: CKD group, n = 34; CAD/CKD: CAD + CKD group, n = 10).

Results

The PFR was significantly impaired after stress in the CKD and CAD + CKD groups compared with controls (p < 0.001 for both). Furthermore, PFR at rest positively correlated with eGFR (r = 0.29, p < 0.001) and inversely correlated with SDS (r = ?0.18, p < 0.05). Multivariate stepwise regression analysis independently associated eGFR with PFR (β coefficient = 0.260, p = 0.002).

Conclusions

Our data suggest that impaired renal function is a significant determinant of LV diastolic dysfunction in patients with suspected CAD.     

Relationship among eccentric hip and knee torques, symptom severity and functional capacity in females with patellofemoral pain syndrome

Objective

To determine the relationships between eccentric hip and knee torques, symptom severity and functional capacity in females with patellofemoral pain syndrome (PFPS).

Design

Within-subject correlational study.

Setting

University biomechanics laboratory.

Participants

10 females diagnosed with PFPS.

Main outcome measures

Eccentric strength of the hip abductors and lateral rotators, and knee extensors were assessed using an isokinetic dynamometer. A 10-cm visual analog scale was used to determine usual knee pain in the last week. The Anterior Knee Pain Scale (AKPS) was used to determine the functional capacity of the patients.

Results

The study found that the greater the eccentric knee extensor and hip lateral rotator torques, the higher the functional capacity of the patients (p = 0.02, r = 0.72; p = 0.02, r = 0.72). It was also shown that the greater hip lateral rotator torque, the less the usual pain reported in the last week (p = 0.004, r = −0.84). Despite the lack of statistical significance (p = 0.11), it was also found a modest negative relationship between the eccentric knee extensor torque and the usual pain reported in the last week (r = −0.56) that was considered clinically meaningful (d = 1.4).

Conclusions

This study showed that eccentric knee extensor and hip lateral rotator torques were associated with functional capacity and pain level in females with PFPS. Further investigations should be carried out to verify the effects of an intervention program focused on the eccentric action of these muscles with respect to the symptoms in patients with PFPS.     

Safety and Efficacy Assessment of Flow Redistribution by Occlusion of Intrahepatic Vessels Prior to Radioembolization in the Treatment of Liver Tumors

We evaluated the feasibility, safety, and efficacy of radioembolization (administered from one or two vascular points) after the redistribution of arterial blood flow in the liver in patients with hepatic neoplasms and arterial anatomic peculiarities (AAP). Twenty-four patients with liver neoplasms and AAP (graded according to Michel’s classification) were included in the study. During pretreatment angiographic planning, all extrahepatic vessels that could feed the tumor were embolized and the intrahepatic vessels occluded in order to redistribute blood flow. The distribution of microspheres was initially assessed by using technetium-99m-labeled macroaggregated albumin (^99mTc-MAA) from one of two vascular points before the administration of yttrium-90 (⁹⁰Y)-radiolabeled resin microspheres. Perfusion of lesions situated in the redistributed segments (L-RS) and nonredistributed segments (L-NRS) were compared by assessing the distribution of ^99mTc-MAA by SPECT/CT. Perfusion was graded as normal, reduced, or absent. ⁹⁰Y resin microspheres were then injected from the same arterial sites as ^99mTc-MAA and the tumor response recorded 3 months later. The tumor response in L-RS was compared with that in L-NRS and graded as better, similar, or worse. Among 11 patients with type I AAP in whom mainly vessels in segments I–III or IV were occluded, perfusion of L-RS was graded as similar (n = 7) or reduced (n = 4). Among the remaining 13 patients with AAP types III (n = 3), V (n = 4), VIII (n = 3), and others (n = 3) in which aberrant arteries were occluded, perfusion of L-RS was graded as similar (n = 9), reduced (n = 3), or absent (n = 1). Overall, ^99mTc-MAA was present in the L-RS of 95.8% patients and the distribution of ^99mTc-MAA in L-RS and L-NRS were graded as similar in 66.6% of patients. Compared with lesions in the L-NRS, tumor response in L-RS was similar in 23 cases and worse in 1 case. No complications were recorded after the administration of ⁹⁰Y resin microspheres. Redistribution of flow in L-RS is feasible and enables a safe and effective delivery of ⁹⁰Y resin microspheres that are able to be distributed via intrahepatic collaterals and access the microvasculature of L-RS.     

Serum caffeine levels after 24 hours of caffeine abstention: observations on clinical patients undergoing myocardial perfusion imaging with dipyridamole or adenosine

Although caffeine attenuates the vasodilatation produced by dipyridamole and adenosine, and is therefore contraindicated when these agents are used for myocardial perfusion scintigraphy, caffeine levels in clinical patients undergoing standard imaging protocols have not been studied. Eighty-six patients undergoing clinically indicated intravenous dipyridamole (n=75) or adenosine (n=11) thallium-201 myocardial perfusion scintigraphy, all of whom reported abstention from products containing caffeine for 24 h, were studied prospectively. Blood samples were drawn prior to initiation of the pharmacologic infusion, and serum caffeine levels were determined using an enzyme immunoassay technique. Results of these determinations were correlated with maximum pulse and blood pressure changes measured during and immediately after the stressor infusion, and thallium imaging findings. Detectable caffeine levels were found in 34 patients (40%), ranging from 0.1 to 5.0 mg/l. There was no significant difference in mean systolic blood pressure decrease or mean pulse increase between patients with caffeine levels > 1.0 mg/l (20.4 ± 18.2 mmHg, 11.0 ± 8.9 BPM; n=5) and those with lower (0.1 to 0.9 mg/1) (15.4 ± 9.5 mmHg, 14.4 ± 8.2 BPM; n=29) or no detectable caffeine levels (18.0 ± 11.5 mmHg, 16.6 ± 10.1 BPM; n=52). Redistribution on thallium imaging was also identified with a similar frequency in these three groups (2/5, 40%; 8/29, 28%; 22/52, 42% respectively). Correspondence to: A.F. Jacobson     

Factors associated with myocardial salvage immediately after emergent percutaneous coronary intervention in patients with ST-elevation acute myocardial infarction

Objective  The amount of myocardial salvage after percutaneous coronary intervention (PCI) is reported to be a major determinant of functional recovery in patients with ST-elevation acute myocardial infarction (MI). However, factors related to the amount of myocardial salvage remain unknown. The goal of this study was to investigate the factors related to the amount of myocardial salvage after emergent PCI in patients with ST-elevation acute MI by incorporating pre- and post-treatment indices and adjunctive treatments. Methods  Technetium-99m myocardial imaging was performed before, immediately after, and one month after emergent PCI in 161 patients with ST-elevation acute MI, and the defect score was serially evaluated. A good myocardial salvage was defined as ≥4 change (before minus immediately after PCI) of the defect score. Results  Good myocardial salvage was observed in 89 patients. Based on nine clinical variables, logistic regression analysis was performed to determine the important variables related to myocardial salvage. Multivariate analysis revealed that earlier time from onset to PCI (χ ² = 6.55, P = 0.01, odds ratio = 2.78), larger defect score before PCI (χ ² = 7.29, P = 0.01, odds ratio = 1.13) and administration of nicorandil before PCI (χ ² = 9.88, P = 0.008, odds ratio = 4.42) were independently associated with good myocardial salvage. Thrombolysis In Myocardial Infarction (TIMI) flow grade <2 before PCI (χ ² = 4.91, P = 0.03, odds ratio = 0.36) and TIMI flow grade ≤2 after PCI (χ ² = 4.82, P = 0.03, odds ratio = 0.31) were independently associated with poor myocardial salvage. In contrast, the number of asynergic segments before PCI, infarct-related artery, adequate collaterals before PCI and stent implantation were not determinants of myocardial salvage. Conclusions  This study demonstrated that patients with a greater improvement of ^99mTc tetrofosmin myocardial uptake immediately after PCI had better recovery of left ventricular function and smaller final infarct size. Reperfusion time and TIMI flow grade ≤2 after PCI were important determinants of myocardial salvage, and nicorandil was a major determinant of myocardial salvage.     

The March of Extrahepatic Collaterals: Analysis of Blood Supply to Hepatocellular Carcinoma Located in the Bare Area of the Liver After Chemoembolization

The purpose of this study was to evaluate changes in vascular supply to hepatocellular carcinoma (HCC) located in the bare area of the liver in patients who were mainly treated with chemoembolization. Twenty-six patients with HCC showing a mean diameter of 3.1 ± 1.4 cm (mean ± standard deviation) were mainly treated with chemoembolization. All patients underwent 2.7 ± 2.3 chemoembolization sessions over 40.1 ± 25.2 months. Tumor feeding branches demonstrated in each chemoembolization session were retrospectively evaluated. Initially, 18 tumors (59.2%) were supplied by the hepatic artery (H) and 8 (30.8%) by both the hepatic and the extrahepatic arteries (H + C). Fourteen tumors (53.8%) recurred at the posterior aspect of the tumor and were supplied by H (n = 4), H + C (n = 5), and extrahepatic collaterals (C) (n = 5). Several tumors recurred despite repeated chemoembolization, and these were supplied by H (n = 1), H + C (n = 7), and C (n = 2) at the second recurrence, by H (n = 1), H + C (n = 2), and C (n = 3) at the third, by H + C (n = 2) and C (n = 2) at the fourth, by H + C (n = 2) and C (n = 2) at the fifth, and by H (n = 1) and C (n = 1) at the sixth. One tumor was supplied by H at the seventh and by H + C at the eighth recurrence. As the number of local recurrences increased, the feeding vessel shifted from H to C. Especially, the right inferior phrenic artery (IPA) and renal capsular artery (RCA) supplied the tumor early, while the small right RCAs, adrenal arteries, and intercostal and lumbar artery supplied late recurrences in turns. In conclusion, HCCs located in the bare area are frequently supplied by extrahepatic vessels initially, while recurrence after chemoembolization is mainly due to extrahepatic blood supply. The right IPA and RCA are common feeding vessels demonstrated early, while other extrahepatic collateral supply from the retroperitoneal circulation occurs in turns during the later course.     

Embedding the assistant practitioner role within the clinical department: A qualitative study

Aim

To evaluate the Assistant Practitioner (AP) role in terms of service delivery and gain insight into the improvements that could be made in embedding this role effectively. This evaluation was timely as the role had been established in radiography for several years and there was limited research which explored its success in practice.

Method

A qualitative approach was used to examine the perceptions of radiology managers using a regional focus group (n = 10) and follow up interviews (n = 4). These were designed to gain an understanding of the managers’ views. Focus groups and interviews were audio recorded and transcribed. Data were analysed using a framework analysis approach to reveal salient issues.

Results

Three main themes representing the perceptions of the role were uncovered and these related to organisational issues, the educational perspective and the individual perspective. This paper is restricted to in depth reporting and analyses of the organisational and individual perspectives only. Analysis revealed several factors facilitated the role in practice but equally other factors inhibited its effectiveness.

Conclusions

There is potential for the AP role to support the work of radiographers and more importantly enhance the care of patients. However, certain individual views should be addressed and the identified changes in departmental organisation attended to, if the role is to develop successfully and become firmly embedded in the radiography service structure.     

Microfracture treatment of single or multiple articular cartilage defects of the knee: a 5-year median follow-up of 110 patients

We compared the results of microfracture in single versus multiple symptomatic articular cartilage defects in the knee in 110 patients with a median age of 38 years (range 15–60). Cases of reoperation of the cartilage defect were classified as failures. Clinical outcome in non-failures was evaluated by the Lysholm score and grading of knee pain and function of the knee by the use of patient-administered visual analog scales (VAS; 0–100). Data were prospectively collected before the operation and at the 2- to 9-year follow-up. The single lesion or the largest of multiple lesions were located on the medial femoral condyle (n = 62), trochlea (n = 18), lateral tibia (n = 11), patella (n = 10) or lateral femoral condyle (n = 9). We treated one (n = 76), two (n = 27) or three (n = 7) lesions with a median total area of 4 cm² (range 1–15). A total of 24 failures (22%) were registered—18% in the single-defect subgroup and 29% in the multiple-defects subgroup. In the remaining group of patients (n = 86), the mean Lysholm score, mean pain-score (0 = no pain; 100 = worst possible pain) and mean function-score (0 = useless; 100 = full function) improved from 51, 52 and 41, respectively, to 71 (P < 0.001), 30 (P < 0.001) and 69 (P < 0.001) at the follow-up. The pain-score was significant lower (P = 0.042), and the function-score significantly higher (P = 0.001) in the group of patients with a single lesion compared to the group with 2 or 3 lesions. The Lysholm score did not differ significantly between the two subgroups (P = 0.06).     

Prognostic utility of increased pulmonary thallium uptake in patients without ischemia

Background

Although the combination of increased pulmonary thallium uptake and ischemia has demonstrated prognostic utility, the value of pulmonary uptake independent of ischemia has not been evaluated critically. Accordingly, our purpose was to evaluate the prognostic utility of thallium lung uptake in patients who do not have stress-induced defects.

Methods and Results

We studied 184 patients who were divided into three groups. Patients with increased pulmonary uptake were grouped into either the normal perfusion (n=48) or fixed defect (n=44) scan group and were compared with a third group (n=92) of control patients who had normal scans and no lung uptake. During a mean follow-up of 23±13 months, there were 13 cardiac events (death or myocardial infarction) and the incidence per year was 0.6%, 2%, and 12% in the control, normal, and fixed defect groups, respectively (p<0.00001). Life table analysis demonstrated greater event-free survival rates in the control and normal groups compared with the group with fixed defects. A Cox regression analysis showed that the number of fixed defects (infarct segments) was the most important independent prognostic factor (p<0.00001) for future cardiac events.

Conclusion

In patients with increased pulmonary thallium uptake and no stress perfusion defects, the prognosis is similar to that of control patients. However, patients with infarct segments and lung uptake have a significantly worse prognosis.     

MRI features of tuberculosis of the knee

Objective  The objective of this study was to describe the magnetic resonance imaging (MRI) features of tuberculosis (TB) of the knee joint. Materials and methods  The MRI features in 15 patients with TB of the knee, as confirmed by histology of the biopsied joint synovium, were reviewed retrospectively. The images were assessed for intra-articular and peri-articular abnormalities. Results  All patients had florid synovial proliferation. The proliferating synovium showed intermediate to low T2 signal intensity. In the patients who were administered intravenous contrast, the hypertrophic synovium was intensely enhancing. Marrow edema (n = 9), osteomyelitis (n = 4), cortical erosions (n = 5), myositis (n = 6), cellulitis (n = 2), abscesses (n = 3), and skin ulceration/sinus formation (n = 2) were seen in the adjacent bone and soft tissue. Conclusion  Synovial proliferation associated with tuberculous arthritis is typically hypointense on T2-weighted images. This appearance, in conjunction with other peri-articular MRI features described, can help in distinguishing TB arthritis from other proliferating synovial arthropathies.     

Age-related signal intensity changes in the corpus callosum: assessment with three orthogonal FLAIR images

The presence of age-related hyperintensities of the corpus callosum has not been thoroughly evaluated. Fifty-two patients of 50 years of age or older (mean, 71 years; range, 50–87 years) were included in this study. Fluid-attenuated inversion recovery images were obtained in three orthogonal planes. Periventricular hyperintensities (PVHs) and deep white matter hyperintensities (DWMHs) were graded according to Fazekas rating scale. Correlations between the presence of hyperintensities in the corpus callosum and age, and the grade of PVH and DWMH were statistically analyzed. PVH was categorized as grade 0 (n=4), grade 1 (n=28), grade 2 (n=10), or grade 3 (n=10). DWMH was categorized as grade 0 (n=4), grade 1 (n=25), grade 2 (n=8), or grade 3 (n=15). Hyperintensity was considered present in the corpus callosum in 31 of the 52 patients (60%). In these 31 patients, PVH was categorized as grade 1 (n=16), grade 2 (n=7), or grade 3 (n=8), while DWMH was categorized as grade 0 (n=1), grade 1 (n=10), grade 2 (n=7), or grade 3 (n=13). The presence of callosal hyperintensities was significantly correlated with age (p=0.001), and with PVH (p=0.04) and DWMH grades (p=0.004). Hyperintensities may be present in the corpus callosum with aging, and are correlated with PVH and DWMH.     

Survival benefit after revascularization is independent of left ventricular ejection fraction improvement in patients with previous myocardial infarction and viable myocardium

Purpose This study was designed to assess the relationships among myocardial viability, changes in left ventricular (LV) ejection fraction after coronary revascularization and long-term event-free survival in patients with previous myocardial infarction and LV dysfunction. Methods We studied 253 patients with previous myocardial infarction and evidence of dysfunctional viable myocardium as assessed by echocardiography and ^99mTc-sestamibi imaging. Coronary revascularization was performed in 142 patients, while 111 were medically treated. In revascularized patients, echocardiography was repeated 12 months later to detect LV ejection fraction improvement, defined as an increase of 5% compared with baseline. All patients were followed for a mean period of 52±29 months. Cardiac death and non-fatal myocardial infarction were considered as events. Results Event-free survival was higher in revascularized than in medically treated patients (P<0.001). Ejection fraction increased by 5% in 82 (58%) revascularized patients, and the extent of viable myocardium was the strongest predictor of such improvement (P<0.001). Event-free survival was similar for patients with (n=82) and patients without (n=60) LV ejection fraction improvement after revascularization, and it was better in revascularized than in medically treated patients in the presence of either substantial (5 viable segments) or low–intermediate (1–4 viable segments) viability (both P<0.01).Conclusion In patients with previous myocardial infarction and evidence of viable myocardium, coronary revascularization procedures improve outcome at long-term follow-up independently of LV ejection fraction improvement.     

Prognostic study of risk stratification among Japanese patients with ischemic heart disease using gated myocardial perfusion SPECT: J-ACCESS study

Background Although the prognostic value of myocardial perfusion imaging using gated single photon emission computed tomography (SPECT) for predicting major cardiac events has been evaluated, little is known about the relevance of this procedure to the Japanese population. Methods A total of 4,031 consecutive Japanese patients with suspected or confirmed ischemic heart diseases were registered at 117 hospitals in the Japanese Assessment of Cardiac Events and Survival Study by Quantitative Gated SPECT investigation. Gated stress/rest myocardial perfusion SPECT was performed and the patients were followed up for 3 years. Segmental perfusion scores and quantitative gated SPECT results were calculated. Major cardiac events were defined as cardiac death, nonfatal myocardial infarction, and severe heart failure. Results During the 3-year follow-up, cardiac death (n = 57) and nonfatal myocardial infarction (n = 39) occurred in 96 patients (2.4%/3 years) when hard events were the endpoints. When severe heart failure was included as an endpoint, major cardiac events that developed in 175 patients (4.3%/3 years) comprised cardiac death (n = 45), nonfatal myocardial infarction (n = 37), and severe heart failure (n = 93). Normal and severely abnormal summed stress score values were associated with low (2.31%/3 years) and high (9.21%/3 years) rates of major cardiac events, respectively. Rates of major cardiac events were significantly higher in patients with ejection fraction (EF) <45% than in those with EF 45% or higher (16.55 vs 2.94%/3 years; P < 0.001). The incidence of major cardiac events within 3 years was also significantly higher among patients with high end-systolic volumes. The major event rates were similar among nondiabetic patients with and diabetic patients without prior myocardial infarction at 5.06% and 5.73%/3 years, respectively. Conclusion Cardiac event rates were significantly lower in the Japanese than in the USA and European populations. However, large myocardial perfusion defects and decreased cardiac function, as well as diabetes mellitus, could be predictors of high event rates and, thus, beneficial for risk stratification of Japanese patients with ischemic heart diseases. Financial support: Japan Cardiovascular Research Foundation     

Cardiac sympathetic neuronal damage precedes myocardial fibrosis in patients with Anderson-Fabry disease

Purpose

Cardiac sympathetic denervation may be detectable in patients with Anderson-Fabry disease (AFD), suggesting its usefulness for early detection of the disease. However, the relationship between sympathetic neuronal damage measured by ¹²³I–metaiodobenzylguanidine (MIBG) imaging with myocardial fibrosis on cardiac magnetic resonance (CMR) is still unclear.

Methods

Cardiac sympathetic innervation was assessed by ¹²³I–MIBG single-photon emission computed tomography (SPECT) in 25 patients with genetically proved AFD. Within one month from MIBG imaging, all patients underwent contrast-enhanced CMR. MIBG defect size and fibrosis size on CMR were measured for the left ventricle (LV) and expressed as %LV.

Results

Patients were divided into three groups according to MIBG and CMR findings: (1) matched normal, without MIBG defects and without fibrosis on CMR (n = 10); (2) unmatched, with MIBG defect but without fibrosis (n = 5); and (3) matched abnormal, with MIBG defect and fibrosis (n = 10). The three groups did not differ with respect to age, gender, α-galactosidase, proteinuria, glomerular filtration rate, and troponin I, while New York Heart Association class (p = 0.008), LV hypertrophy (p = 0.05), and enzyme replacement therapy (p = 0.02) were different among groups. Although in patients with matched abnormal findings, there was a significant correlation between MIBG defect size and area of fibrosis at CMR (r² = 0.98, p < 0.001), MIBG defect size was larger than fibrosis size (26 ± 23 vs. 18 ± 13%LV, p = 0.02).

Conclusion

Sympathetic neuronal damage is frequent in AFD patients, and it may precede myocardial damage, such as fibrosis. Thus, ¹²³I–MIBG imaging can be considered a challenging technique for early detection of cardiac involvement in AFD.

     

Adult midgut malrotation: multi-detector computed tomography (MDCT) findings of 14 cases

Purpose

To describe MDCT findings in adult patients of midgut malrotation and to correlate the types of adult midgut malrotation with its complications.

Materials and methods

CT scans were performed on 14 adult patients with midgut malrotation. The images were reviewed retrospectively by one radiologist. Abnormal intestinal location, mesenteric vascular arrangement, extraintestinal anomalies and complications were evaluated and correlated with patterns of adult midgut malrotation.

Results

The 14 cases of adult midgut malrotation revealed the following CT findings: intestinal malposition (n = 14), abnormally oriented mesenteric vessels (n = 8), extraintestinal anomalies (n = 14). These cases were classified into six types: complete nonrotation (n = 3), nonrotated duodenum and partially rotated colon (n = 6), isolated nonrotation of the duodenum (n = 2), partial rotation of the duodenum and colon (n = 1), partially rotated duodenum (n = 1) and isolated colonic partial rotation (n = 1). Four of these patients had accompanying complications, including volvulus (n = 2), right paraduodenal hernia (n = 1) and gastroduodenal intussusception (n = 1), respectively.

Conclusion

Imaging features of adult midgut malrotation are characteristic. Adult midgut malrotation has various manifestations, and types of midgut malrotation may be closely related to their complications.