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PubMed2000

Exercise-induced negative U waves in precordial leads as a marker of viable myocardium in patients with recent anterior myocardial infarction.

Patients with recent anterior myocardial infarction and a significant stenosis in the left anterior descending coronary artery were divided into two groups according to the presence (Group A, n=24) or absence (Group B, n=77) of negative U waves in the precordial leads during exercise stress test to compare the coronary arteriographic findings. Both total occlusion of the left anterior descending coronary artery (79% vs. 31%, P<0.01)) and good (index=2, 3) collateral circulation to the territory of this artery (92% vs. 36%, P<0.01) were observed more often in group A than in group B. In order to determine whether detection of exercise-induced negative U waves in precordial leads can predict the presence of viable myocardium, the 56 patients (20 of group A and 36 of group B) with total or subtotal occlusion of the left anterior descending coronary artery were studied further. The coronary arteriographic and exercise 201Tl scintigraphic findings were compared between the groups. Good collateral circulation to the territory of this artery was observed significantly (P<0.05) more often in group A (100%) than in group B (61%). Patients with multivessel disease were significantly (P<0.05) more prevalent in group A (70%) than in group B (33%). The incidence of a significant partial redistribution in the anteroseptal area in the 20Tl images 4 h after exercise was significantly (P<0.01) higher in group A (85%) than in group B (39%). In 29 patients with anterior Q-wave myocardial infarction and exercise-induced ST elevation in precordial leads, a significant 201Tl redistribution in the anteroseptal area was observed in 8 (80%) of 10 patients of group A in contrast to only 4 (21%, P<0.05) of 19 in group B. In the diagnosis of the viability associated with 201Tl redistribution in the anteroseptal area by the finding of exercise-induced negative U waves, the sensitivity was 67% and the specificity was 88% in these patients. We conclude that exercise-induced negative U waves in precordial leads are a convenient and specific marker for the presence of viable myocardium in patients with recent anterior myocardial infarction.

Collateral Circulation↗
PubMed1993

Therapeutic potential of potassium channel openers in peripheral vascular disease and asthma.

Potassium channel opener's (KCOs) were originally thought of as nonselective smooth muscle relaxants. However, recent investigations in animal models of both peripheral vascular disease (PVD) and asthma have revealed interesting effects of these drugs as unexpectedly low doses. Hemodynamically, KCOs are interesting in PVD since they have little effect on blood supply to normally perfused skeletal muscle, but enhance perfusion to chronically ligated ischemic tissue. In animal PVD models, SDZ PCO-400 and cromakalim have been shown to improve recovery of muscle energy stores from ischemia or to preserve performance under conditions of ischemic contracture. Beneficial effects in rat PVD models were manifest at doses below those affecting systemic blood pressure and may be attributable to a selective dilatation of collateral vessels. With regard to the airways, the apparent efficacy of KCOs as antiasthmatic drugs seems not to be attributable solely to their bronchodilator activity. Although KCOs elicit no antiinflammatory effect in animal models, studies with SDZ PCO-400 in guinea pigs sensitized to antigen or treated with immune complexes have revealed that expression of airway hyperreactivity is significantly inhibited at drug doses exhibiting only modest bronchodilator activity. At least part of this action can be attributed to inhibition at the level of neural innervation of the airways, possibly through attenuation of nonadrenergic noncholinergic (NANC) transmission.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed2001

[MR-angiography in portal hypertension. State of the art].

When imaging the portal vascular system colour-coded sonography and CT angiography are used as an alternative to intraarterial DSA. Today fast CE 3D-MRA is the imaging modality of choice in the diagnostic of patients with portal hypertension. It enables a clear picture of the portalvenous vascular system and portalsytemic shunts. Statements regarding velocity and direction of blood flow can be made with additional use of TOF and PC techniques. CE-3D MRA can be used preoperatively before liver transplantation or shunt surgery. In the follow-up of interventional or surgical procedures exact statements concerning haemodynamically significant pathologies e.g. vascular thromboses, stenoses and occlusions can be made. Patient consent is symplify and the numbers of complications can be reduced as well as duration of surgery minimized applying this technique.

Collateral Circulation↗
PubMed2003

Invasive and non-invasive evaluation of spontaneous arteriogenesis in a novel porcine model for peripheral arterial obstructive disease.

Our current knowledge regarding the efficacy of factors stimulating collateral artery growth in the peripheral circulation primarily stems from models in small animals. However, experimental models in large sized animals are a prerequisite for extrapolation of growth factor therapy to patients with peripheral atherosclerotic obstructive disease. Therefore, we have developed a novel porcine femoral artery ligation model using non-invasive and invasive evaluation techniques. In 12 young farm pigs and nine older minipigs, a ligation of the superficial femoral artery was performed. Using an intra-arterial catheter, phosphate buffered saline (PBS) was administered with a first-pass over the collateral vascular bed. Directly after ligation as well as after 2 weeks of continuous infusion of PBS, perfusion of the leg was measured using various flow and pressure parameters. Using a pump driven extracorporal system, collateral conductance was determined under maximal vasodilatation. Conductance decreased after acute ligation to similar levels in both young farm pigs as well as the older minipigs (both 9.3% of normal perfusion) and recovered after 2 weeks to a higher value in farm pigs compared with minipigs (22.4 vs. 12.7% of normal; P<0.05). Angiography using both X-ray and magnetic resonance imaging was performed to visualize the formed collateral arteries. To the best of our knowledge this is the first in vivo pig model for hemodynamic assessment of growth of collateral arteries in the peripheral circulation, that is suitable for evaluation of arteriogenic effects of growth factors or genes.

Angiography↗
PubMed1997

Radiologic evaluation of penile arterial anatomy in arteriogenic impotence.

Functional and anatomic evaluation of penile arterial blood flow is essential in the work up of erectile dysfunction. Duplex ultrasonography is an ideal screening modality with cavernosal mean peak systolic blood flow velocity being the most sensitive predictor of arterial disease. Arterial variability of the penis may affect sonographic evaluation leading to frequent misinterpretation and therefore pudendal arteriography remains the current gold standard for penile arterial evaluation. Appreciation of the type and frequency of anatomic variants and potential collateral routes is important in interpreting penile arteriograms and in evaluating the hemodynamic significance of suspected arterial disease.

Arteries↗
PubMed2000

The use of ultrasound in the diagnosis of injuries of the ulnar collateral ligament of the thumb.

We describe the use of a specialist referral clinic and ultrasound assessment for all injuries to the ulnar collateral ligament of the metacarpophalangeal joint of the thumb presenting to an Accident and Emergency (A&E) department. Senior House Officers in the A&E department were able to correctly diagnose only 45% of the ruptures of the ulnar collateral ligament. The overall agreement between specialist clinic examination and ultrasound for injury to the ulnar collateral ligament was 85% (kappa 0.647). When compared with the operative finding ultrasound had a positive predictive value for rupture of 94%. An algorithm is presented for the assessment of injuries to the ulnar collateral ligament in A&E departments.

Adolescent↗
PubMed2004

Simvastatin-induced myocardial protection against ischemia-reperfusion injury is mediated by activation of ATP-sensitive K+ channels.

OBJECTIVES: Previous studies have suggested that the 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors attenuate ischemia-reperfusion injury. We investigated whether pretreatment with simvastatin reduces myocardial infarct size and whether glyburide, a non-selective inhibitor of the ATP-sensitive K channels, abrogates this infarct size-limiting effect. METHODS: Sprague-Dawley rats were treated with either simvastatin (20 mg/kg per day) or saline alone for 3 days. Additional groups of rats were treated as above and on the fourth day they received intravenous glyburide (0.3 mg/kg). All rats underwent 30 min of coronary artery occlusion followed by 180 min of reperfusion. Ischemic myocardium at risk was assessed with blue dye and infarct size with triphenyltetrazolium chloride. RESULTS: Infarct size, expressed as a percentage of the myocardium at risk, was significantly smaller in the simvastatin group (n = 8, 20.8 +/- 3.4%) than in the placebo group (n = 6, 40.1 +/- 2.7%) (P = 0.001). Glyburide abolished the protective effect of simvastatin with infarct size being 34.2 +/- 6.9% and 29.7 +/- 3.9% of the area at risk in the simvastatin group (n = 7) and placebo (n = 7) group, respectively (P = 0.58). CONCLUSIONS: Simvastatin significantly reduced myocardial infarct size. The protective effect was completely abrogated by glyburide, strongly suggesting that this protective effect is mediated via activation of the ATP-sensitive K channels.

ATP-Binding Cassette Transporters↗
PubMed1996

Acamprosate (calcium acetylhomotaurinate) enhances the N-methyl-D-aspartate component of excitatory neurotransmission in rat hippocampal CA1 neurons in vitro.

The taurinate analog acamprosate (calcium acetylhomotaurinate) has received considerable attention in Europe for its ability to prevent relapse in abstained alcoholics. To determine the mechanism of acamprosate actions in the CNS, we superfused acamprosate onto rat hippocampal CA1 pyramidal neurons using an in vitro slice preparation. In current-and voltage-clamp recordings, acamprosate (100 to 100 microM) superfusion had little effect on resting membrane potential or input slope resistance. Acamprosate had no effect on Ca(2+)-dependent action potentials when tetrodotoxin was used to block Na+ spikes. In whole-cell voltage-clamp recordings, and in the presence of tetraethylammonium and Cs+ to block K+ channels, acamprosate had little effect on a Cd(2+)-sensitive inward current likely to be a high voltage-activated Ca2+ current. However, in both current- and voltage-clamp recordings, acamprosate significantly increased the N-methyl-D-aspartate (NMDA) component of excitatory postsynaptic potentials evoked by stimulation of Schaffer collaterals in the stratum radiatum, in the presence of the selective non-NMDA (R,S)-alpha-amino-3-hydroxy-5-methylisoxazole-4-proprionic acid kainate) glutamate receptor antagonist 6-cyano-7-nitro-quinoxaline-2,3-dione and the GABAA receptor antagonist bicuculline. Acamprosate had inconsistent or no effects on the stratum radiatum-evoked non-NMDA component of the excitatory postsynaptic potentials, in the presence of bicuculline and the NMDA antagonist DL-2-amino-5-phosphonovalerate. Acamprosate, on average, had little effect on the late inhibitory postsynaptic potentials thought to be mediated by GABAB receptors. In the presence of tetrodotoxin to block synaptic transmission, acamprosate dramatically increased inward current responses in most CA1 neurons to exogenous NMDA applied by pressure or superfusion, with reversal on washout of acamprosate. These data suggest that acamprosate may act postsynaptically to increase the NMDA component of excitatory transmission to hippocampal CA1 pyramidal neurons. Considering the known interaction of ethanol with NMDA receptors, this acamprosate modulation of NMDA receptor-mediated neurotransmission could provide a mechanism of action underlying the clinical efficacy of acamprosate.

Acamprosate↗
PubMed1996

Assessment of central pulmonary arteries in patients with obstructive lesions of the right ventricle: comparison of MR imaging and cineangiography.

OBJECTIVE: MR imaging and cineangiography were compared in the evaluation of central pulmonary arteries in patients with obstructive lesions of the right ventricular outflow tract. SUBJECTS AND METHODS: Prospectively, we obtained multiplanar spin-echo cardiac-gated MR images and cineangiograms in 29 patients who had obstructive lesions of the right ventricular outflow tract (31 examinations). Blinded first observers evaluated the presence, size, confluence, and stenoses of the pulmonary artery and the presence of aortopulmonic collaterals. Blinded second observers evaluated the presence and size of the pulmonary artery. RESULTS: Each imaging technique revealed pulmonary arteries that were not shown by the other technique. We measured pulmonary arteries as being smaller on MR images; however, we found good correlation between the two techniques (r value for right pulmonary arteries = .82, r value for left pulmonary arteries = .88). MR imaging revealed five of six stenoses in the left pulmonary artery, but our observers falsely identified five right pulmonary arteries as stenotic from MR images. Interobserver variability and intraobserver variability in estimating size of the pulmonary artery on MR images and cineangiograms were similar and were less than variability when paired estimations in the same patient with both imaging techniques were compared. CONCLUSIONS: MR imaging and cineangiography should be viewed as complementary techniques.

Adolescent↗
PubMedDate not supplied

Cerebral hemodynamics in asymptomatic patients with internal carotid artery occlusion: a dynamic susceptibility contrast MR and transcranial Doppler study.

BACKGROUND AND PURPOSE: Perfusion imaging with dynamic susceptibility contrast MR imaging (DSC-MRI) has been used to evaluate hemodynamic status in patients with symptomatic occlusive cerebrovascular disease. The aim of the present study was to determine the hemodynamic changes occurring in asymptomatic patients with unilateral internal carotid artery (ICA) occlusion by use of DSC-MRI with transcranial Doppler (TCD) measurement of the breath-holding index (BHI). METHODS: Nine patients with asymptomatic unilateral ICA occlusion underwent DSC-MRI and TCD examination. One patient was excluded from final analysis because of severe movement artifacts. On a separate workstation, regional cerebral blood volume (rCBV), regional cerebral blood flow (rCBF), and regional mean time to peak (rMTT) were calculated on the basis of signal decay rate during the passage of gadolinium bolus through the sampled volume in the territory of the middle cerebral artery. TCD-BHI was calculated in all patients. Six healthy subjects underwent the same MR protocol as the patients. RESULTS: Compared with control subjects, patients with unilateral ICA occlusions had hemodynamic changes in the ipsilateral hemisphere: rCBF was significantly lower than in controls (P <.01), and r MTT was significantly increased in both white (WM) and gray matter (GM) in the affected side (WM: P <.01; GM: P <.05). No statistically significant difference in rCBV was found in the group of patients (occluded versus contralateral, P <.1) or between the patient and control groups (occluded side versus controls, P <.1). The correlation of rCBV and BHI showed a strong relation of the two variables, showing a decrease of the latter when the former increased. CONCLUSION: DSC-MRI is a valuable tool for measuring hemodynamic changes in the presence of carotid disease with hemodynamic impairment. In our opinion, hemodynamic changes and efficiency of collateral pathways can be evaluated in occlusive carotid disease by using paired measurement of BHI and DSC-MRI. In the patient group, MR-determined rCBV and TCD-determined BHI showed a significant inverse correlation, suggesting similar significance of the two indices.

Angiography, Digital Subtraction↗
PubMedDate not supplied

Blood pressure changes in feeders to cerebral arteriovenous malformations during therapeutic embolization.

We recorded blood pressures in feeding arteries of cerebral arteriovenous malformations with microcatheters before, during, and after embolization in awake patients. Our embolization results corroborate reports of intraoperative measurements that show an immediate increase in blood pressure after ligation. Demonstration of abrupt hemodynamic changes gives additional credence to the theory of normal perfusion pressure breakthrough and to theories of neurologic change based on vascular steal phenomena. Furthermore, pressure changes occurred earlier than visible slowing of flow during the embolization, suggesting that this is a more sensitive guide with which to monitor the progress of the embolization than is serial angiography.

Adult↗
PubMed1980

The inflammatory responses of rats depleted of lymphocytes or with an artificial obstruction of the thoracic duct.

Rats selectively depleted of lymphocytes by chronic drainage from the thoracic duct during a 3-day period presented a marked lymphopenia, and decreased responses to carrageenin injected into one of the hind paws. The intensity of the inflammatory responses in thse animals was restored by the i.v. administration of suspensions of viable or lysed lymphocytes, collected from the spleen or lymph of normal animals. A spontaneous reversal of the depressed responses to carrageenin was observed 40 days after the period of lymph drainage, when lymphocyte counts were again normal in blood. If highly inbred rats were used, the i.v. injection of syngeneic lymphoid cells was equally effective in restoring the inhibityed inflammatory responses resulting from lymphocyte depletion. Artificial obstruction of the thoracic duct, with interruption of lymphocyte recirculation, was followed by decreased lymphocyte counts in blood and severely depressed inflammatory responses to carrageenin. This unresponsive state was corrected as the animals recuperated, probably coincidentally with the development of collateral lymph channels and as the temporarily disturbed blood picture returned to normal. It is concluded that lymphocytes can participate in the development of non-immune inflammation through the release of pro-inflammatory factors. This release is independent of previous sensitization of the cells.

Animals↗
PubMed1997

[Overview of the most frequent clinical manifestations of peripheral arterial occlusive disease in the elderly, its diagnosis and stage-related therapy].

The peripheral artery occlusive disease is a widely spread disease and its diagnosis, treatment options and consequences are frequently underestimated. Especially for the old patient, preservation of an extremity may mean mobility and quality of life. The increasing life expectancy and behaviour of prosperity including a lack of mobility are causing a rise in the frequence of atherosclerotic diseases. The prevalence of occlusive vascular diseases in patients between 55 to 64 years of age is currently 11% and is, therefore, a wide-spread disease. However, the socio-economic relevance of the occlusive vascular diseases is frequently underestimated. It causes both very high direct costs (treatment procedures, prostheses etc) as well as high indirect costs (permanent disability). Therefore, early diagnosis and treatment plays an important role in the avoidance of a progression of the disease. For an early diagnosis of the stage I of occlusive vascular diseases it makes sense to examine the vessels of patients at risk (i.e. diabetes mellitus, hypertension, hyperlipidemia, nicotine abuse, and overweight). Dopplerultra-sound and oscillometry are highly sensitive and specific diagnostic measures. The eradication of risk factor and the treatment of the secondary diseases plays the most important role in this disease stage without symptoms. A specific vessel training is indicated during stage II to encourage the development of collateral blood flow. Additionally, an interventional diagnostic and therapy should be considered in this stage with limitations in the daily activities. The administration of vasoactive drugs is controversly discussed. The acetylsalicylic acid (ASA) is remaining the most investigated substance for reducing the progress of the arteriosclerotic process. The administration of ticlopidine is justified in cases of ASA-allergies. The stages III and IV are characterized by pain at rest and necrosis. Firstly, the indication for a transcutaneous transluminal angioplasty, thrombolysis or bypass-surgery should be proofed. If procedures of revascularization are not possible, prostaglandines may improve the pain at rest and wound healing. Beside the stage of the occlusive vascular disease, the presence of risk factors, the physical status of the patient, and the location of the occlusion are of great importance for the decision about the treatment procedure.

Adult↗
PubMed1998

[A rare mediastinal-hilar pseudotumor: esophageal and azygos vein varices].

Mediastinal pseudotumors are present in less than 5% of patients with long-standing portal hypertension. These pseudotumors may be caused by para-esophageal collateral vessels or greatly dilated azygos or hemiazygos veins. Enhanced CT seems to be the best tool for the diagnosis and in evaluating the overall status of portosystemic collateral vessels. In this case report, MRI ruled out tissular mass by showing vascular signal.

Aged↗
PubMed2001

Global myocardial blood flow and global flow reserve measurements by MRI and PET are comparable.

Coronary flow reserve (CFR) measurements have been widely used in assessing the functional significance of coronary artery stenosis because they are more sensitive in predicting major cardiac events than angiographically detected reductions of coronary arteries. Myocardial blood flow can be determined by measuring coronary sinus (CS) flow with velocity-encoded cine magnetic resonance imaging (VEC-MRI). The purpose of this study was to compare global myocardial blood flow (MBF) and CFR measured using VEC-MRI with MBF and CFR measured using positron emission tomography (PET). We measured MBF at baseline and after dipyridamole-induced hyperemia in 12 male volunteers with VEC-MRI and PET. With VEC-MRI, MBF was 0.64 +/- 0.09 (ml/min/g) at baseline and 1.59 +/- 0.79 (ml/min/g) at hyperemia, which yielded an average CFR of 2.51 +/- 1.29. With PET, MBF was 0.65 +/- 0.20 (ml/min/g) at baseline and 1.78 +/- 0.72 (ml/min/g) at hyperemia, which yielded an average CFR of 2.79 +/- 0.97. The correlation of MBFs between these two methods was good (r = 0.82, P < 0.001). The CFRs measured by MRI correlated well with those measured using PET (r = 0.76, P < 0.004). These results suggest that MRI is a useful and accurate method to measure global MBF and CFR. Therefore, it would be suitable for studying risk factor modifications of vascular function at an early stage in healthy volunteers.

Adult↗
PubMed2003

How the stiffness of meniscal attachments and meniscal material properties affect tibio-femoral contact pressure computed using a validated finite element model of the human knee joint.

In an effort to prevent degeneration of articular cartilage associated with meniscectomies, both meniscal allografts and synthetic replacements are subjects of current interest and investigation. The objectives of the current study were to (1) determine whether a transversely isotropic, linearly elastic, homogeneous material model of the meniscal tissue is necessary to achieve a normal contact pressure distribution on the tibial plateau, (2) determine which material and boundary condition (attachments) parameters affect the contact pressure distribution most strongly, and (3) set tolerances on these parameters to restore the contact pressure distribution to within a specified error. To satisfy these objectives, a finite element model of the tibio-femoral joint of a human cadaveric knee (including both menisci) was used to study the contact pressure distribution on the tibial plateau. To validate the model, the contact pressure distribution on the tibial plateau was measured experimentally in the same knee used to create the model. Within physiologically reasonable bounds on five material parameters and four attachment parameters associated with a meniscal replacement, an optimization was performed under 1200 N of compressive load on the set of nine parameters to minimize the difference between the experimental and model results. The error between the experimental and model contact variables was minimized to 5.4%. The contact pressure distribution of the tibial plateau was sensitive to the circumferential modulus, axial/radial modulus, and horn stiffness, but relatively insensitive to the remaining six parameters. Consequently, both the circumferential and axial/radial moduli are important determinants of the contact pressure distribution, and hence should be matched in the design and/or selection of meniscal replacements. In addition, during surgical implantation of a meniscal replacement, the horns should be attached with high stiffness bone plugs, and the attachments of the transverse ligament and deep medial collateral ligament should be restored to minimize changes in the contact pressure distribution, and thereby possibly prevent the degradation of articular cartilage.

Adult↗
PubMed2001

Prediction of acute left main coronary artery obstruction by 12-lead electrocardiography. ST segment elevation in lead aVR with less ST segment elevation in lead V(1).

OBJECTIVES: We sought to determine the electrocardiographic (ECG) features associated with acute left main coronary artery (LMCA) obstruction. BACKGROUND: Prediction of LMCA obstruction is important with regard to selecting the appropriate treatment strategy, because acute LMCA obstruction usually causes severe hemodynamic deterioration, resulting in a less favorable prognosis. METHODS: We studied the admission 12-lead ECGs in 16 consecutive patients with acute LMCA obstruction (LMCA group), 46 patients with acute left anterior descending coronary artery (LAD) obstruction (LAD group) and 24 patients with acute right coronary artery (RCA) obstruction (RCA group). RESULTS: Lead aVR ST segment elevation (>0.05 mV) occurred with a significantly higher incidence in the LMCA group (88% [14/16]) than in the LAD (43% [20/46]) or RCA (8% [2/24]) groups. Lead aVR ST segment elevation was significantly higher in the LMCA group (0.16 +/- 0.13 mV) than in the LAD group (0.04 +/- 0.10 mV). Lead V(1) ST segment elevation was lower in the LMCA group (0.00 +/- 0.21 mV) than in the LAD group (0.14 +/- 0.11 mV). The finding of lead aVR ST segment elevation greater than or equal to lead V(1) ST segment elevation distinguished the LMCA group from the LAD group, with 81% sensitivity, 80% specificity and 81% accuracy. A ST segment shift in lead aVR and the inferior leads distinguished the LMCA group from the RCA group. In acute LMCA obstruction, death occurred more frequently in patients with higher ST segment elevation in lead aVR than in those with less severe elevation. CONCLUSIONS: Lead aVR ST segment elevation with less ST segment elevation in lead V(1) is an important predictor of acute LMCA obstruction. In acute LMCA obstruction, lead aVR ST segment elevation also contributes to predicting a patient's clinical outcome.

Acute Disease↗
PubMed1995

Renal arteries: evaluation with optimized 2D and 3D time-of-flight MR angiography.

PURPOSE: To compare two-dimensional (2D) and three-dimensional (3D) time-of-flight (TOF) techniques in magnetic resonance (MR) angiography of renal arteries. MATERIALS AND METHODS: In 46 patients, MR angiography was performed with 3D tilted optimized non-saturating excitation (TONE), 3D fast imaging with steady precession (FISP), and 2D fast low-angle shot (FLASH) during breath holding. Intraarterial angiography was used as a reference. MR angiograms were evaluated for stenoses, length of renal arteries, accessory arteries, venous overlap, and image quality. RESULTS: The 3D TONE sequence was best for detection of severe stenoses (sensitivity, 100%; specificity, 89%), delineation of accessory arteries, and image quality. Overlap of renal veins was the most important disadvantage of 2D FLASH. Decreased saturation effects, however, can be advantageous in 2D TOF imaging. CONCLUSION: Use of the 3D TONE sequence provided improved image quality and diagnostic value compared with 3D FISP technique. The 2D TOF sequence can be useful in combination with the 3D TONE sequence.

Adult↗