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PubMed2004

Power Doppler ultrasound imaging for quantification of urinary bladder neck blood flow changes.

This study was designed to evaluate power Doppler imaging for assessment of urinary bladder neck blood flow in comparison with laser Doppler flowmetry (LDF) in an animal model. Transrectal power Doppler ultrasound (US) and LDF of the urinary bladder neck were performed in three anesthetized pigs during comparative cystometry. Normal saline (NaCl) was used for the first run, followed by a second run with 0.2 mol/L potassium chloride (KCl). Standardized sonographic equipment settings (Acuson Sequoia 512); MountainView, CA) were used for power Doppler imaging. Computer-assisted calculation of color pixel density (CPD) of power Doppler images was performed using Scion Image) software image analysis. Tissue perfusion units (TPU) were measured using a BLF21 laser Doppler flowmeter (Transonic Systems Inc., Ithaca, NY, USA). The power Doppler results were compared with the findings obtained by LDF. NaCl filling resulted in a mean CPD increase at the bladder neck from 18.65 (+/- 1.78) at empty bladder to 37.8 (+/- 1.84) at 100 mL and to 88.32 (+/- 1.35) at full bladder capacity (C(max)) of 270 mL, respectively. With KCl filling, a mean CPD increase from 18.65 (+/- 1.78) to 59.63 (+/- 0.5) at 100 mL and 110.82 (+/- 2.98) at full bladder capacity (270 mL) was observed. The CPD increase was significantly higher for KCl than with NaCl (p < 0.001). With NaCl filling, bladder neck blood flow increased from 22 TPU (empty) to 46 TPU (100 mL) and 62.5 TPU at C(max), compared to 22 TPU, 50 TPU and 102.5 TPU with KCl. CPD and TPU measurements showed a strong correlation at p = 0.01. In conclusion, transrectal power Doppler US image quantification is a feasible and accurate method for assessing blood flow changes in the urinary bladder neck.

Animals↗
PubMed2001

Comparing Early to Middle Miocene floras and probable vegetation types of Oberdorf N Voitsberg (Austria), Bohemia (Czech Republic), and Wackersdorf (Germany).

The Early Miocene vegetation of western Styria, Austria, is reconstructed on the basis of detailed investigations of leaves and diaspores from the mining area Oberdorf N Voitsberg. In this paper, the flora and probable vegetation are compared with other assemblages of similar age from the Czech Republic and Germany to elucidate the diversity of wetland and mesophytic plant communities. The floristic composition and the vegetational units represented in Oberdorf are compared to the middle part of the Most Formation (M Most Fm), Cypris Shale, Mydlovary Formation (Mydlovary Fm) of Bohemia, and the Wackersdorf mining area of Bavaria. Among these sites, Oberdorf is extremely poor in hydrophytes and reed-like monocotyledons, indicating rare pond-like habitats as well as possibly more closed swamp forest conditions than, e.g. in the M Most Fm. In Oberdorf, relatively high pH-values in the lignite-forming swamps and the possible scarcity of acidic, nutrient-poor (sandy) soils have probably influenced the floristic composition of the azonal communities. The peat-forming associations in all regions share the abundance of Glyptostrobus europaeus. However, distinct differences in the accompanying elements, such as Taxodium dubium (present and abundant only in the M Most Fm) indicate even stronger floristic variability of Early(/Middle) Miocene peat-forming and riparian plant communities than previously expected. The virtual absence of Pinus, Engelhardia, Comptonia, and probably also of Quercus kubinyii/Quercus drymeja in the megafossil record of Oberdorf can possibly be explained by the edaphic conditions. The abundance of Sequoia abietina (absent in all the other compared sites), which we assign to riparian (and mesophytic) forests in Oberdorf, may have been favoured by rich alluvial soils.In the mesophytic associations, thermophilous elements of the Lauraceae, Mastixiaceae, Symplocaceae, and Rutaceae are diverse. Usually they include Trigonobalanopsis rhamnoides/Trigonobalanopsis exacantha, an evergreen Fagaceae. This assemblage type corresponds with the Younger Mastixioid Flora sensu Mai. The Younger Mastixioid Flora is best developed in Wackersdorf, less distinct in Oberdorf, and likely in the Cypris Shale and Mydlovary Fm. It is not traceable in the M Most Fm.

Journal Article↗
PubMed1998

New concept in echocardiography: harmonic imaging of tissue without use of contrast agent.

BACKGROUND: Endocardial border detection is important for echocardiographic assessment of left-ventricular function. Second harmonic imaging of contrast agents enhances this border detection. We discovered that harmonic imaging improves tissue visualisation even before contrast injection. We therefore sought objectively to demonstrate the degree of enhancement of endocardial and myocardial visualisation. METHODS: An ATL HDI-3000 scanner with software for contrast harmonic imaging was used to record short-axis images of the left ventricle in 27 patients with possible myocardial disease and 22 controls, in the fundamental mode and with harmonic imaging. A computer program measured the relative grey-scale values within six segments of the endocardium and myocardium. An Acuson Sequoia scanner equipped with software for tissue harmonic imaging was used to investigate the reproducibility of ejection-fraction calculations in 22 patients with ischaemic heart disease. FINDINGS: Harmonic imaging produced brighter endocardium within each segment. Relative to the mean grey value of the total imaging sector, the values for harmonic and fundamental imaging were 171.5 vs 85.6% (p<0.0001) in end diastole and 194.1 vs 106.7% (p<0.0001) in end systole. Results for the myocardial segments were also significantly better for harmonic imaging. Structure enhancement of similar magnitude was seen among patients and healthy controls. Use of harmonic imaging reduced the proportion of unacceptable images by 14-46% in different views and improved the reproducibility of biplane ejection-fraction measurements. INTERPRETATION: In comparison with fundamental imaging, the relative endocardial and myocardial brightness is enhanced by harmonic imaging.

Aged↗
PubMed1981

The Parkmedic Program: prehospital care in the national parks.

The Parkmedic Program provides training and on-going supervision of national park rangers involved in advanced prehospital medical care in Yosemite, Kings Canyon, and Sequoia National Parks in California. This includes intravenous catheterization and drug administration in emergency situations. Course structure, experience to date, and recommendations for future programs are presented.

Adult↗
PubMed1995

Use of epinephrine for anaphylaxis by emergency medical technicians in a wilderness setting.

STUDY OBJECTIVE: To describe a case series of emergency medical technician-basic (EMT-B)-administered epinephrine for anaphylaxis in a wilderness setting. DESIGN: Case series of patients in anaphylaxis who received epinephrine subcutaneously from EMT-Bs. SETTING: National park rural/wilderness emergency medical service system covering 863,000 acres and serving approximately 2 million annual visitors. PARTICIPANTS: Prehospital care providers were National Park Service rangers with EMT-B training. Patients in the series were visitors to Sequoia and Kings Canyon National Parks with anaphylaxis resulting from insect stings. INTERVENTION: Subcutaneous administration of epinephrine by EMT-Bs trained in recognition, understanding, and treatment of anaphylaxis. RESULTS: Eight patients with anaphylaxis resulting from Hymenoptera stings, from June 1992 through September 1993, received EMT-B-administered epinephrine. All patients improved clinically after treatment with epinephrine within 25 minutes. No major side effects occurred. CONCLUSION: Our data suggest that EMT-B-administered epinephrine is safe when used by EMT-Bs in the rural/wilderness setting, with appropriate physician supervision. Further study in large trials will be required to demonstrate safety and efficacy.

Adolescent↗
PubMed1999

[The Doppler color detection of internal mammary artery anastomoses and a functional assessment of their patency].

BACKGROUND: Left internal mammary artery coronary graft patency is usually evaluated invasively by cardiac catheterization. The objective of this study was to assess the ability of a high-frequency transthoracic Doppler echocardiographic system in the evaluation of patency and flow velocities changes in left internal mammary artery. METHODS: Twenty-two patients (63 +/- 9 years, 17 male) who had previously undergone left internal mammary artery to left anterior descending artery were evaluated by transthoracic echocardiography, with an Acuson Sequoia C256 equipment (Acuson, Mountain view, USA), placing the transducer (5 MHz) in the second-third left intercostal space. Left internal mammary artery flow was considered to be found in the presence of one systolic/diastolic biphasic blood flow. Dipiridamol 0.5 mg/kg was administered in absence of contraindications in order to evaluate the flow reserve. RESULTS: In 16 patients (73%), a biphasic systolic-diastolic flow was visualized. Peak velocity of systolic and diastolic waves was 38 +/- 13 and 37 +/- 15 cm/s, respectively. Eleven patients received i.v. dipiridamol 0.5 mg/kg. After dipiridamol, systolic and diastolic velocities rose from 32 +/- 8 to 43 +/- 14 cm/s (p = 0.0429) and from 25 +/- 8 to 50 +/- 17 cm/s (p = 0.0002), respectively (an increasing of 33 +/- 22% and 103 +/- 46% over the baseline, respectively). CONCLUSION: This descriptive study shows that a non-invasive functional evaluation of left internal mammary artery grafts by a transthoracic approach with a high-frequency echocardiographic equipment is possible.

Aged↗
PubMed2001

Development of three-dimensional power Doppler ultrasound imaging of fetoplacental vasculature.

To develop an off-line system for three-dimensional (3-D) ultrasound (US) reconstruction of fetoplacental vasculature using colour segmentation and reconstruction software and to determine sources of error in fully freehand ultrasound image acquisition. US images were acquired freehand with the Acuson Sequoia (5C 2-MHz transducer) using power Doppler. After digital transfer to a personal computer, CQ Analysis software (Kinetic Imaging Ltd, Liverpool, UK) was used to segment the colour information from these images, and the resulting 8-bit grey-scale images were used for 3-D rendering using commercial software (VoxBlast, Vaytek Inc., Fairfield, IA, USA). 2-D scanning, software and freehand acquisition accuracy were assessed using a linear test rig and distance and volume phantoms (Dansk Phantom Service Ltd); 2-D scanning accuracy was within 1.3%, and software reconstruction accuracy within 1% for x and y planes and up to 3% for the z plane. Fully freehand acquisition was associated with a 12% to 18% mean percentage error in distance measurement in the plane of acquisition. Volumetric reconstruction inaccuracy was between 1.5% and 19.7% for precisely separated images and between 16.2% and 39.2% for fully freehand image acquisition. Rendered 3-D US vascular images clearly delineated vascular anatomy within the placenta and cord. Fully freehand 3-D US does have a role in off-line reconstruction of vascular anatomy, although variability in the z plane precludes its use for volumetric measurement. (E-mail: a.welsh@ic.ac.uk)

Female↗
PubMed2004

Cl K-edge X-ray spectroscopic investigation of enzymatic formation of organochlorines in weathering plant material.

The contribution of halocarbons from plant weathering to the total organohalogen budget of terrestrial systems is gaining recognition. To evaluate the formation of such halocarbons, speciation of chlorine in Sequoia sempervirens (redwood) needles was examined in the presence of an external chloroperoxidase (CPO) enzyme using Cl K-edge X-ray absorption spectroscopy. The Cl forms in fresh and naturally weathered needles and in model laboratory reactions were compared. To provide a straightforward analogue to the enzymatic chlorination in plants, chlorination reactions were conducted for phenol, a common moiety of plant macromolecules. Plant material chlorination was also examined in the presence of hypochlorite in an ancillary mechanistic investigation. The dominant form of Cl in fresh, unreacted plant material was found to be inorganic Cl-, which was partially converted to organochlorine in the presence of CPO. Chlorination is affected by the nature of reactant (CPO, H2O2) addition, reaction time, and temperature. The organochlorines produced in these laboratory investigations closely resemble those produced during the natural weathering of redwood needles. A striking consistency in chlorine speciation observed among the various sample types suggests that (i) CPO produced by terrestrial organisms could play a vital role in the generation of organochlorines associated with the degradation of plant material and (ii) initial targets of enzymatic chlorination might include lignin-like macromolecules rich in aromatic character and hydroxyl groups. These findings lend further credibility to a significant biogenic contribution to the global organohalogen burden by elucidating a probable route of enzymatic chlorination of natural organic matter in terrestrial systems.

Chloride Peroxidase↗
PubMed1999

Sequoiatones A and B: Novel Antitumor Metabolites Isolated from a Redwood Endophyte.

Sequoiatones A and B were isolated from the fungus Aspergillus parasiticus, an endophytic fungus of the coast redwood, Sequoia sempervirens. The compounds were isolated from the methanol extract of the mycelial mat of the fungus when grown in liquid culture for 21 days. The compounds were isolated because of their brine shrimp lethality, which served as an excellent guide for chromatographic purification. Full details of the isolation and characterization of sequoiatones A and B are provided herein, along with the test results from the NCI human tumor 60 cell-line screen.

Journal Article↗
PubMed2006

Natural history of periocular capillary haemangiomas: changes in internal blood velocity and lesion volume.

AIM: Although the clinical characteristics of childhood periocular capillary haemangiomas are well known, serial measurements of blood velocity and lesion size are unknown. This investigation was designed to measure the changes in maximum blood velocity and estimated size of lesion in children with capillary haemangioma not requiring active intervention. STUDY DESIGN: Retrospective case-note review for a cohort of children with capillary haemangioma involving the eyelid and orbit. PATIENTS AND METHODS: Children with periocular capillary haemangioma, under the care of the Orbital unit at Moorfields Eye Hospital between 1996 and 2005, were monitored clinically and with repeated ultrasonographic examination. Volume estimates were calculated as an ovoid based on the three maximum orthogonal measurements for the haemangioma, and blood velocity was assessed by Colour Flow Mapping, Colour Doppler Energy Imaging, and Spectral Doppler techniques using a Sequoia 512 Acuson scanner. RESULTS: Twenty-four children (12 boys) had initial assessment by 18 months of age, and the haemangioma increased in size in 14/24 (58%), the increase being between 4 and 931% of initial volume estimate. The largest measured size for an individual haemangioma appears inversely related to the child's age at measurement, this mirroring a similar trend in measurements for the maximum blood velocity. Blood velocity measurements also tend to decrease with time, the peak velocity being before 1 year of age in the majority (15/24; 62%). In many children, both volume estimates and blood velocities show a cyclic variation-this occurring with increasing intervals between the maxima, before a final decay in both parameters. Although, for the whole group, there was no correlation (correlation coefficient=0.29) between estimated size and measured blood velocity, some individual children showed a significant correlation between the two parameters. The age at maximum blood velocity appeared to precede the age at maximum volume in most children, and in many there was an orbital anomaly detectable on ultrasonographic examination, even with complete clinical resolution of the haemangioma. CONCLUSIONS: Ultrasonographic examination of periocular capillary haemangiomas show that these lesions have a very high blood velocity in feeding vessels-about 2-3 orders of magnitude greater than normal capillary beds-and that the velocity and volume of such lesions undergo a cyclic variation during their natural history. Evidence suggests that both velocity and volume decrease with time, although often not returning to zero on ultrasonography (unlike the clinical resolution of the lesions). In most children, blood velocity peaks before volume estimates and this might suggest that decreasing perfusion leads to later tissue atrophy and involution of the haemangioma.

Blood Flow Velocity↗
PubMed2001

Power Doppler dual-frame triggering of myocardial contrast echocardiography: a quantitative video intensity analysis.

AIM: The purpose of this study was to define the pattern of myocardial contrast observed during triggered dual-frame power Doppler imaging. METHODS AND RESULTS: Ten patients with no previous history of myocardial infarction underwent a continuous intravenous infusion of Optison at 0.5 ml/min. Triggered, sequential dual-frame power Doppler imaging was performed from an apical four-chamber view using a prototype Acuson Sequoia imaging system. The average triggering interval was once every four cardiac cycles, and the average interval between sequential frames was 50 msec. Video intensity analysis was performed in five myocardial regions of interest, and the percent decrease in video intensity of the destruction frames in each region of interest was determined by subtracting the destruction frame video intensity from the fill frame video intensity. The percent decrease in video intensity varied significantly by myocardial location (P < 0.001), with greater destruction seen in the apical than in the basal regions. CONCLUSION: This preliminary study demonstrates that power Doppler dual-frame triggering produces nonuniform decreases in video intensity, which likely represent nonuniform microbubble destruction. These results have important implications for the interpretation of myocardial perfusion patterns using this technique.

Contrast Media↗
PubMed2002

The in vitro and in vivo ultrasonographic appearances of the angio-seal percutaneous closure device.

PURPOSE: To assess the ultrasound appearances of the Angio-Seal device in an animal model and in twenty patients following catheterization of the femoral artery. MATERIALS AND METHODS: Ten patients were scanned within 8 hours of their procedure (early group) and 10 at two to four days (delayed group) using Acuson Aspen and Sequoia scanners. Colour flow images were taken and Doppler spectral analysis was performed proximal proximal to, at and distal to the Angio-Seal device. Early and delayed in vitro images were taken in a water bath in which the Angio-Seal device was deployed across a normal porcine aorta for comparison. RESULT: In the ten early patients colour and Doppler drop out were seen in 100 percent and 90 percent respectively compared with 90 percent and 60 percent in the delayed group. The device was seen in 30 percent and 90 percent in early and delayed groups respectively. In the in vitro study the components of the device were seen and a posterior acustic shadow noted. This shadow was less obvious and the polymer anchor more easily seen in the delayed group. CONCLUSION: The Angio-Seal device produces a consistent artifact when scanned soon after deployment. These appearances could potentially be mistaken for a vascular occlusion by the unwary in the appropriate clinical setting of acute post catheterisation lower limb ischaemia however an awareness of the normal sonographic appearances of this device would make this misinterpretation unlikely.

Absorbable Implants↗
PubMed2001

Guidance by ultrasound of intra-articular injections in the knee and hip joints.

OBJECTIVE: To develop and assess a stable method for ascertaining the placement of intraarticular injections for osteoarthritis (OA) in the hip and knee. METHODS: Injections into the hip or knee joint with e.g. hyaluronan or cortisone were performed under the guidance of ultrasound. For this purpose an Acuson Sequoia apparatus and a 8-15 MHz transducer were used. After perforation of the capsule with a 21 G needle, 0.5-1 ml of atmospheric air and 1 ml lidocain 1% was injected with simultaneous recording of the ultrasound signals. This procedure was undertaken before the injection of the medication through the in situ needle. RESULTS: In the hip joint the injected air could readily ascertain the placement of the injection with a sharp echoic contrast forming on the ultrasound picture respecting the joint cavity. In the knee joint the procedure gave the best results in joints which have a small amount of fluid in either the suprapatellar bursa or in a pouch regularly observed over the lateral joint margin. However, also in some so-called 'dry' knee joints the air could be traced in the bursa by ultrasound. CONCLUSION: By the injection of air, it is possible to test the placement of intraarticular injections in both hip and knee joints. This procedure will give a supplementary documentation of the injection as compared to a mere ultrasonographic demonstration of the position of the needle in the joint. The method is proposed as a tool for both learning purposes and quality assurance in daily therapy.

Adjuvants, Immunologic↗
PubMedDate not supplied

[Evaluation of the reproducibility of Doppler ultrasonographic measurements in obstetrics].

BACKGROUND: Are obstetric doppler ultrasonographic measurements of the fetal and maternal flow parameters reproducible? PATIENTS AND METHODS: For internal quality management, doppler ultrasonographic measurements were performed on 81 patients (random screening sample) with an Acuson Sequoia Ultrasound at the Universitätsfrauenklinik Marburg. Successively two experienced investigators measured the umbilical artery, medial cerebral artery, and the uterine arteries. The correlation between the measurements of the two investigators was presented in a spread chart. In order to exclude systematic differences between the measurements, linear regression was analyzed and the distance to the abscissa was calculated. A relative divergence of more than 20% was determined as a non corresponding measurement. RESULTS: The distance of the linear regression to the abscissa was calculated for the four vessels: umbilical artery 0.4 (95% CI; 0.124 - 0.486), medial cerebral artery 0.9 (95% CI; 0.534 - 1.264), right uterine artery 0.2 (95% CI; 0.124 - 0.305), and left uterine artery 0.2 (95% CI; 0.121 - 0.317). Concerning the four arteries, a divergence of more than 20% between the two investigators was found: umbilical artery 16%, medial cerebral artery 42%, right uterine artery 28%, and left uterine artery 37%. CONCLUSIONS: Because the interobserver variability was surprisingly high and acceptable correlation could be stated only for the umbilical artery, internal quality standards are essential. Routine use of different devices should be made after careful consideration only, especially if clinical decisions are to be based on them.

Blood Flow Velocity↗
PubMed2005

De Quervain's subacute thyroiditis -- colour Doppler sonography findings.

AIM: De Quervain's subacute nonsuppurative thyroiditis has been well characterised clinically: there usually is pain in the region of the thyroid due to local pressure. Typically, the patient feels generally ill with fever. Signs of inflammation (raised ESR and CRP) are measurable laboratory parameters. Occasionally, there is transient hyperthyroidism followed by hypothyroidism. Little data is available on the vascularisation of the thyroid in this clinical entity. PATIENTS AND METHODS: Twenty-one patients with confirmed De Quervain's subacute thyroiditis were investigated and the findings were analysed retrospectively (clinical features, sonography, cytology in some cases). Ultrasound devices (Siemens Elegra and Acuson Sequoia) with 7 and 12 MHz ultrasound transducers and modern technology (harmonic imaging, panorama imaging and sensitive colour Doppler units with standardised instrument settings) were used. RESULTS: The structures of the thyroid was found to be inhomogeneous. The hypoechoic to nonechoic areas corresponded to the inflamed areas. An alteration in the morphology and topographic distribution was observed in the course of the illness. Normal or slightly increased vascularisation in the echogenically "healthy" regions of the thyroid were found in colour Doppler sonography. The peak systolic velocity (PSV) in the afferent arteries (superior and inferior thyroid arteries) was in the normal range (< 40 cm/s). The hypoechoic/nonechoic map-like areas showed a reduction or complete absence of blood flow. CONCLUSION: De Quervain's subacute thyroiditis can be conclusively diagnosed by sonography in more than 90 % of cases based on the history, typical clinical features and clinical test parameters indicating signs of inflammation. Colour Doppler sonography can be useful in differential diagnosis of unclear cases.

Acute Disease↗
PubMed2000

Is the technically limited echocardiographic study an endangered species? endocardial border definition with native tissue harmonic imaging and Optison contrast: a review of 200 cases.

OBJECTIVE: Our goal was to determine whether contrast adds diagnostic value to both fundamental and native tissue harmonic imaging (NTHI) for endocardial border definition. METHODS: Two hundred consecutive patients who underwent stress echocardiography imaging were studied in either fundamental (n = 52) or NTHI mode (n = 148) with an Acuson Sequoia echocardiographic system. Contrast agent (Optison) was administered (0.5 to 1 mL) for enhancement of endocardial borders. Two- and 4-chamber views were analyzed before and after administration of contrast at peak stress for grading of 5 endocardial border segments. Scores from 0 to 5 were assigned to each study for all the images both before and after contrast (0 = 0 segments completely visualized; 5 = 5 segments completely visualized). RESULTS: The use of Optison contrast significantly enhanced border definition when imaging was performed in either fundamental or NTHI mode. Addition of contrast resulted in better endocardial border definition in fundamental mode (4.1 + or - 1.0 versus 2.3 + or - 1.3, P <.001). However, in NTHI mode, the presence of contrast resulted in enhanced definition of endocardial border compared with its absence (4.8 + or - 0.5 versus 3.3 + or - 1.1, P <.001). The combination of NTHI and contrast resulted in more visualization of endocardium when compared with the combination of fundamental imaging and contrast (4.8 + or - 0.5 versus 4.1 + or - 1.0, P <.001). In addition, interobserver agreement for border detection increased from 83% in fundamental mode without contrast to 95% with the use of NTHI with Optison (P <.001). CONCLUSION: As defined in 200 cases, the combination of NTHI with Optison contrast results in nearly complete and consistent endocardial border definition.

Albumins↗
PubMed2000

Localization of the ventricular preexcitation site in Wolff-Parkinson-White syndrome with Doppler tissue imaging.

PURPOSE: The objective of this study was to evaluate the ability of Doppler tissue imaging (DTI) to localize the ventricular emergence site of accessory atrioventricular pathways (Wolff-Parkinson-White syndrome). METHODS: Thirty-three patients were studied prospectively by Doppler tissue imaging (128XP and Sequoia 256 echocardiographic systems; Acuson, Mountain View, Calif) before investigation of Wolff-Parkinson-White syndrome and after radiofrequency ablation of the accessory pathways. The normal appearance of the ventricular contractions was defined in a group of 10 control subjects. The preexcitation zone was determined as a zone of maximum acceleration in "DTI acceleration mode" or as a coded contraction zone in "DTI velocity mode," at the time of the delta wave or before the onset of the QRS complex. RESULTS: The earliest ventricular activation site was correctly localized for 12 of the 15 left-sided pathways (8 anterior or anterolateral, 2 lateral or posterolateral, 2 inferior). When wall motion abnormalities were detected in the left ventricle by DTI, the left-sided localization was confirmed by electrophysiologic exploration. For the right-sided pathways, the localization was correct in only 4 of 11 cases (3 posteroseptal and 1 anterolateral). After effective ablation in all patients, the abnormalities corresponding to the electrophysiologic data disappeared totally in only 11 of 16 patients. CONCLUSION: In the presence of Wolff-Parkinson-White syndrome, DTI localizes contraction abnormalities associated with early activation of a part of the ventricle. However, the interpretation of the images remains difficult because the normal coding of the contraction of the ventricular walls depends on the incidence for which they are investigated. This noninvasive examination seems to be an effective tool for localizing the left-sided accessory pathways of the left ventricle, in particular in the anterior, anterolateral, or inferior walls.

Adult↗