Search PubMed⌕ Search

Biomedical subjects

J N Dacher

Publications and source records attributed to J N Dacher.

At least 19 recordsLinked to original sources
PubMed2006

[Myocarditis versus myocardial infarction in diabetic patients: a new role for non invasive imaging].

A young diabetic patient was referred to our institution for clinical symptoms of myopericarditis. Cardiac MRI and MDCT of the coronary arteries were performed successively. They demonstrated an acute myocardial infarction related to a left circumflex coronary artery occlusion which was treated by stent angioplasty. This case suggests that cardiac MR and possibly cardiac MDCT could be proposed in patients with a suspected myopericarditis, especially if diabetes mellitus is associated.

Adult↗
PubMed2005

[Management of abdominal trauma in children].

Management of abdominal trauma in children has considerably changed over the last fifteen years. This is mainly due to advances in imaging techniques combined with a more conservative approach. Non-surgical management is frequently preferred with close clinical and biological surveillance, in addition to comprehensive imaging evaluation. The imaging work up must be adapted to this conservative approach. The increasing availability of helical CT technology and Doppler US imaging can be used to advantage in the evaluation of these patients. Euratom Directive 97-43 identifies children as a particular subgroup of patients with regards to exposure to ionizing radiation thus requiring us to reconsider the routine use of CT in this patient subpopulation and promoting the use of alternate imaging techniques. Based on a review of the literature as well as our own experience, where we currently favor US with selective use of CT, the advantages and pitfalls of each imaging technique will be reviewed. Ultimately, the imaging protocol for each patient should be based on availability, expertise, and individual clinical setting.

Abdominal Injuries↗
PubMed2004

[Non-invasive coronary angiography by multidetector spiral computed tomography and magnetic resonance imaging].

Coronary angiography is the reference standard to confirm the presence and severity of coronary stenoses. Given the invasiveness of this procedure, a noninvasive mean allowing to visualize coronary anatomy would be of obvious clinical interest. Multidetector spiral computed tomography and magnetic resonance imaging are new and promising techniques for noninvasive detection of significant coronary stenoses. The purpose of this article is to review the present knowledge on these noninvasive techniques.

Coronary Angiography↗
PubMed2004

[Section planes for cardiac MRI].

The recent developments of synchronized cardiac MRI are a unique opportunity for the radiology community to integrate cardiac imaging. This educational aticle aims to help radiologists and technicians to obtain cardiac planes comparable to those of cardiac ultrasound and gated SPECT. Of course, cardiac planes described herein for MRI also apply to multi-detector CT.

Aorta, Thoracic↗
PubMed2004

[Anomalies of myocardial contractility: CT and MR appearance].

Cardiac output relies on an appropriate contractile function. It is mandatory to recognize kinetic alterations of the myocardium and to precise their extent (i.e. segmental, regional or global), to quantify their consequences on the function of the cardiac pump, and to assess if the underlying disease is reversible or fixed.

Cardiomyopathy, Hypertrophic↗
PubMed2004

[Cardiac tumors].

Metastases are the most frequent tumors of the heart even though they seldom are recognized. Most primary cardiac tumors are benign. The main role of imaging is to differentiate a cardiac tumor from thrombus and rare pseudotumors: tuberculoma, hydatid cyst. Echocardiography is the fist line imaging technique to detect cardiac tumors, but CT and MRI are useful for further characterization and differential diagnosis. Myxoma of the left atrium is the most frequent benign cardiac tumor. It usually is pedunculated and sometimes calcified. Sarcoma is the most frequent primary malignant tumor and usually presents as a sessile infiltrative tumor. Lymphoma and metastases are usually recognized by the presence of known tumor elsewhere of by characteristic direct contiguous involvement. Diagnosing primary and secondary pericardial tumors often is difficult. Imaging is valuable for diagnosis, characterization, presurgical evaluation and follow-up.

Adult↗
PubMed2004

[Cardiomyopathies].

Cardiomyopathies include a wide variety of cardiac diseases. The value of MR imaging is not only to provide information about cardiac function, but also to detect the underlying cause of the disease.

Cardiomyopathy, Dilated↗
PubMed2003

Endosonography in the evaluation of anal function after primary repair of a third-degree obstetric tear.

BACKGROUND: Disruption of the anal sphincter occurs in 0.6%-6% of women during delivery and almost half have persistent defecatory symptoms despite primary repair. Our aim was to prospectively analyse anal endosonography and rectoanal manometry after primary repair of a third-degree obstetric tear in order to compare the findings with the clinical outcome. METHODS: Twenty-one women aged 27-41 (mean 31.5 years) who had undergone primary suture of a third-degree disruption of the anal sphincter were interviewed on their pelvic floor function and explored by manometry and endosonography 4 months after delivery. RESULTS: Twelve women had anal incontinence. External sphincter defect was identified on endosonography in 22% continent and in 91% incontinent women (P < 0.01). The presence of an external sphincter defect was associated with anal incontinence in 91.7%. Surgical repair was identified on endosonography in 88% continent women and in 25% incontinent women (P < 0.03). The combination of a visible surgical repair and absence of defect was highly associated with normal continence (91.7%). Squeezing pressures were higher in continent women (87 +/- 23 cm H2O) than in incontinent women (48 +/- 36 cm H2O; P = 0.04), but no anal pressure threshold could achieve better results than endosonography in predicting the clinical outcome. CONCLUSION: After primary repair of a third-degree obstetric tear, endosonographic pattern of the anal sphincter correlates with the continence status.

Adult↗
PubMed2003

Impact of Wiener filter in determining the left ventricular volume and ejection fraction using thallium-201 gated SPECT.

Patient morphology, as well as the acquisition and reconstruction parameters, may influence the evaluation of the left ventricular volume (LVV) and left ventricular ejection fraction (LVEF) using gated single-photon emission computed tomography (SPECT). The purpose of this study was to examine the influence of gender and reconstruction filter on the measurement of LVV and LVEF using 201Tl gated SPECT. Using a static torso phantom, a female shape was created by the addition of two saline solution-filled balloons fixed on the anterior rib cage. The following parameters were similar for all acquisitions: 90 degrees dual-head gamma camera; 32 projections; 64x64 matrix (pixel size=6.77x6.77 mm); two 20% energy windows centred at 70 and 167 keV. The following acquisition times were tested: 1.25, 10, 20, 30 and 40 s per projection, leading to a total of 10 successive acquisitions. The effect of over-sampling was tested by 2.5 post-acquisition zooming. All SPECT images were successively reconstructed using filtered back-projection with Butterworth and Wiener filters. The effect of gender and reconstruction filter was also studied in 30 patients (15 males and 15 females) with a low likelihood of coronary artery disease. LVVs were calculated using QGS software. By multivariate analysis, the following factors influenced the accuracy of phantom measurement using QGS software: zooming (F=49, P<0.0001), phantom shape (F=61, P<0.0001) and filter type (F=240, P<0.0001). LVV was underestimated in the female shape phantom, even when using the Wiener filter. In patients, LVV and LVEF measurements were independently influenced by gender (P<0.0001) and filter (P<0.0001), but not by zooming. In conclusion, it was demonstrated that LVV was significantly decreased in the female shape phantom, suggesting a significant impact of breast interposition. This underestimation was minimized by use of the Wiener filter. In patients, the impact of the Wiener filter on the assessment of LVVs and LVEF was powerful, but independent of gender, and failed to correct the underestimation of LVVs and the overestimation of LVEF in females.

Algorithms↗
PubMed2003

[Ultrasound and dynamic contrast-enhanced MR imaging of a multifocal hemangioendothelioma in an infant].

Multifocal liver hemangioendothelioma is a rare tumor occurring in children less than 6-months-old. It can be life threatening during the first year of life because of possible hemorrhage or high output heart failure. Slow and often spontaneous recovery is the rule. The association of ultrasound and contrast-enhanced dynamic MR seems sufficient to establish the diagnosis.

Gadolinium↗
PubMed2003

[MR Colonography].

MR Colonography is a new non invasive technique for colonic imaging. The first studies in man appeared in 1997-1998. MR Colonography requires an endoluminal contrast and combines volumetric acquisition with sophisticated image post-processing referred as virtual endoscopy. New technical developments such as fecal tagging were recently introduced. MR Colonography now enters into a phase of clinical evaluation. This article describes the available technique as well as pitfalls and artifacts with regard to our own experience.

Artifacts↗
PubMed2002

[Prenatally detected multicystic renal dysplasia and associated anomalies of the genito-urinary tract].

PURPOSE: To analyze the prevalence of genitourinary malformations associated with multicystic dysplastic kidney (MCDK). PATIENTS: and method: A retrospective analysis of medical and imaging records of 54 neonates who had the prenatal diagnosis of MCDK was carried out. All infants had the following examinations during their first month of life: ultrasound, voiding cystourethrography and intravenous urography. Genital and urinary abnormalities were recorded. RESULTS: Vesicoureteric reflux was present ipsilaterally in 17% cases, on the opposite side in 31% cases. Ureteropelvic junction obstruction was found on the opposite side in 7% cases. Four cases of megaureters, one child with ureteric duplication, 3 boys with posterior urethral valves, 1 with reflux into the ejaculatory duct, one case of megacystis with reflux and one child with ureterocele were identified. Genital anomalies were: 2 cases of seminal vesicle cysts, one case of absent testis, 5 children with inguinal hernia, one boy with incomplete foreskin and one with hypospadias. CONCLUSION: Embryology may explain the highest prevalence of genito-urinary abnormalities on both sides in neonates with MCDK. Hence, a prompt clinical and uroradiological evaluation in these patients with a single functional kidney should be performed.

Abnormalities, Multiple↗
PubMed2002

[Imaging of a foreign body in the submandibular space].

Foreign bodies in the oral cavity are infrequent in children. In spite of a negative clinical exploration, US and CT showed the suction cup of a rubber-tipped dart in the left submandibular space of a 3 year-old child. Surgery could be guided by these investigations.

Abscess↗
PubMed2002

[Vesicoureteric reflux and functional voiding dysfunction in children].

PURPOSE: To analyze the efficacy of the different treatments of vesicoureteric reflux (VUR) associated with reflex bladder sphincter dyssynergia (RBSD). PATIENTS AND METHODS: The medical records of 33 children (28 girls) aged 4 to 12 years presenting reflex bladder sphincter dyssynergia and vesicoureteric reflux have been reviewed. The most common clinical symptom was urinary tract infection. Voiding dysfunction included: dysuria, urinary leak, enuresia, urgency, constipation. In most cases, vesicoureteric reflux was low grade (grade 1, n=9; grade 2, n=18; grade 3, n=6) and bilateral (n=18). Three types of treatments have been utilized: reimplantation, reeducation, medical treatment (diet, antibio-prophylaxis, anti-cholinergics). RESULTS: Eleven children (2 with a solitary kidney) underwent early reimplantation which was effective on vesicoureteric reflux but 6 of them had post-operative voiding dysfunction and 5 had a new episode of urinary infection. Six had reeducation first then they underwent reimplantation. Sixteen children had an exclusive medical treatment (13 with reeducation). In 9 children vesicoureteric reflux disappeared (one child still complains of voiding dysfunction). In 7, voiding dysfunction improved but vesicoureteric reflux is still present. CONCLUSION: The management of vesicoureteric reflux associated with reflex bladder sphincter dyssynergia is complex. Surgery should certainly not be the initial treatment. However, it can remain useful if one wishes to get complete resolution of reflux.

Anti-Bacterial Agents↗
PubMed2001

Neurological presentation of a congenital disorder of glycosylation CDG-Ia: implications for diagnosis and genetic counseling.

The congenital disorders of glycosylation (CDG) constitute a new group of recessively inherited metabolic disorders that are characterized biochemically by defective glycosylation of proteins. Several types have been identified. CDG-Ia, the most frequent type, is a multisystemic disorder affecting the nervous system and numerous organs including liver, kidney, heart, adipose tissue, bone, and genitalia. A phosphomannomutase (PMM) deficiency has been identified in CDG-Ia patients and numerous mutations in the PMM2 gene have been identified in patients with a PMM deficiency. We report on a French family with 3 affected sibs, with an unusual presentation of CDG-Ia, remarkable for 1) the neurological presentation of the disease, and 2) the dissociation between intermediate PMM activity in fibroblasts and a decreased PMM activity in leukocytes. This report shows that the diagnosis of CDG-Ia must be considered in patients with non-regressive early-onset encephalopathy with cerebellar atrophy, and that intermediate values of PMM activity in fibroblasts do not exclude the diagnosis of CDG-Ia.

Age of Onset↗