A. Grignon
Université de Montréal
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Featured researches published by A. Grignon.
Circulation | 2004
Marie-Josée Raboisson; Jean-Claude Fouron; J. Lamoureux; Line Leduc; A. Grignon; F. Proulx; S. Gamache
Background—In the twin-to-twin transfusion syndrome (TTTS), pressure rather than volume overload is increasingly considered as a key factor in the pathogenesis of the cardiomyopathy of the recipient twin. If this is the case, cardiac dysfunction should be among the first signs observed with TTTS. The objective of this study was to determine whether intertwin differences in myocardial function are modified early in the course of TTTS and whether they can help to differentiate this condition from intrauterine growth restriction (IUGR). Methods and Results—Eight variables were analyzed on the first fetal echocardiography on 21 pairs of twins with TTTS and 11 with IUGR. No difference was found between the 2 groups for the cardiothoracic ratio, pulsatility indices in the umbilical and middle cerebral arteries, and peak velocity of the middle cerebral artery. Significant difference was found for ventricular septal thickness, but with no association with the conditions under study. With TTTS, left ventricular shortening fraction was consistently greater in the donor twins, and myocardial performance indices (MPIs) were elevated in the recipient twins. This increase in MPI was caused by a lengthening of the isovolumic periods compared with those of the donor twin: left ventricular and right ventricular isovolumic periods 0.105±0.047 and 0.097±0.026 seconds, respectively, for the recipient twins versus 0.0561±0.46 and 0.065±0.03 seconds, respectively, for the donor twins (P<0.001). These changes in the isovolumic periods were mainly due to significant prolongation of isovolumic relaxation times. A change in left ventricular MPI ≥0.09 combined with a change in right ventricular MPI ≥0.05 would identify a TTTS with a sensitivity of 75% and a false-positive rate of 9%. Conclusions—The observed diastolic function impairment goes along with the pressure-overload pathogenic concept proposed in TTTS. Assessment of intertwin difference in MPI is a valuable tool for early differential diagnosis between TTTS and isolated IUGR.
Pediatric Radiology | 1987
Denis Filiatrault; D. Longpré; Heidi Patriquin; Gilles Perreault; A. Grignon; J. Pronovost; Jacques Boisvert
During a 5.5-year retrospective study (1979–84) 170 children with blunt abdominal trauma were investigated with intravenous urography (IVU), ultrasound (US) and scintigraphy. For the investigation of the last 71 children (after 1982) a 4th generation CT scanner was available in the same department. The results of radiologic investigations were compared with clinical outcome in 157 and results at laparotomy in 13 children. During the study period, real time US became the first line screening tool, and was combined with IVU in suspected renal trauma. In spite of permanent accessibility of CT since November 1982, the latter was used only in complex diagnostic problems or in children with multiple injuries (8% of the series). There were no deaths resulting from abdominal trauma. During the study, the incidence of splenectomy and exploratory laparotomy decreased, and no diagnostic peritoneal lavage were performed after 1980.
Pediatric Radiology | 2004
Sanna Toiviainen-Salo; Laurent Garel; A. Grignon; Josée Dubois; Françoise Rypens; Jacques Boisvert; Gilles Perreault; Jean Claude Décarie; Denis Filiatrault; Chantale Lapierre; Marie-Claude Miron; Nancy Bechard
This review article aims at summarizing the data regarding fetal and neonatal hydronephrosis, at correlating controversial data with the differences in the practice of obstetrical sonography from one country to another, and finally, at presenting our own criteria for fetal renal collecting system dilatation along with our own guidelines of postnatal investigation.
American Journal of Medical Genetics | 1999
Nathalie Brun; Yves Robitaille; A. Grignon; Brian H. Robinson; Grant A. Mitchell; Marie Lambert
Pyruvate carboxylase (PC) is a key enzyme in the gluconeogenesis and anaplerotic metabolic pathways. PC deficiency is a rare autosomal recessive disorder with three clinical presentations: an infantile form, a severe neonatal form, and a benign form. We report brother and sister sibs with the severe form of PC deficiency. Both had macrocephaly and severe ischemia-like brain lesions at birth and died in the first week of life with intractable lactic acidemia. In the girl, increased head circumference and periventricular leukomalacia (PVL) were detected on fetal ultrasonography at 29.4 weeks of gestation. PC activity in cultured skin fibroblasts was <2% of control. This is the first reported case of ischemia-like brain lesions documented prenatally in PC deficiency. The lesions were detected at a time of maximal periventricular metabolic demand. We postulate that energy deprivation induced by PC deficiency impairs astrocytic buffering capacity against excitotoxic insult and compromises normal microvascular morphogenesis and autoregulation, both mechanisms leading to cystic degeneration of the periventricular white matter. Discovery of cystic PVL on cerebral ultrasound at birth in a newborn infant presenting with primary lactic acidemia is highly suggestive of PC deficiency. Moreover, PC deficiency should also be considered when ischemia-like brain lesions are documented by fetal ultrasonography.
Pediatric Radiology | 1991
Laurent Garel; Denis Filiatrault; Mary L. Brandt; A. Grignon; Jacques Boisvert; Gilles Perreault; Heidi Patriquin
A retrospective study from 1980 to 1990 shows 29 ovarian cysts in 27 patients diagnosed by prenatal ultrasound performed between 28 and 38 weeks of gestation. Ten patients underwent surgery, 17 patients were observed with serial ultrasound. Delayed good quality sonograms after spontaneous resolution of the cyst in a selected group of 7 patients showed restoration of a normal ovarian anatomy. The size of the cyst and/or its sonographic characteristics are the 2 main factors for deciding a conservative or a surgical management.
American Journal of Obstetrics and Gynecology | 1985
Evelyne Rey; Louise Duperron; Robert J. Gauthier; Michel Lemay; A. Grignon; Jacques LeLorier
The role that the new antiarrhythmic agents, such as verapamil and amiodarone, might play in the therapeutic strategy of tachycardia-induced fetal heart failure remains to be determined.
Pediatric Radiology | 2000
Laurent Garel; Josée Dubois; G. Azzie; Denis Filiatrault; A. Grignon; Salam Yazbeck
Objective. To assess the effectiveness of preoperative manual detorsion in acute testicular torsion.¶Materials and methods. Between June 1998 and March 1999, seven patients presenting with testicular torsion underwent manual manipulation under US monitoring in order to restore the flow to the testis prior to surgery (orchidopexy). All detorsions were lateral in direction. The success of the manoeuvre was assessed both clinically and sonographically and confirmed at surgery.¶Results. Six manoeuvres were successful in restoring flow to the testis. The failed attempt in the seventh patient was due to failure to manipulate beyond an initial 1 1/2 rotations (540 °).¶Conclusions. Preoperative detorsion is the fastest way to relieve testicular ischaemia. However, manual detorsion of the spermatic cord is not a substitute for surgical exploration and bilateral orchidopexy is still necessary.
Ultrasound in Obstetrics & Gynecology | 2006
G. Gorincour; Françoise Rypens; S. Toiviainen-Salo; A. Grignon; R. Lambert; F. Audibert; Laurent Garel; J.-C. Fournet
To evaluate the functional prognosis of kidneys affected prenatally by urinomas.
Pediatric Radiology | 1990
Heidi Patriquin; Gilles Perreault; A. Grignon; Jacques Boisvert; Denis Filiatrault; Laurent Garel; Hervé Blanchard
A study was conducted on 156 children, in whom the portal veins were measured using standard real time ultrasonography. Knowledge of the normal dimension may be important in patients with liver disease.
Fetal Diagnosis and Therapy | 2015
Gabriella Martillotti; Isabelle Boucoiran; Amélie Damphousse; A. Grignon; Eric Dubé; Ahmed Moussa; Sarah Bouchard; Lucie Morin
Introduction: The objective of the study was to establish the predictive value of prenatal ultrasound markers for complex gastroschisis (GS) in the first 10 days of life. Material and Methods: In this retrospective cohort study over 11 years (2000-2011) of 117 GS cases, the following prenatal ultrasound signs were analyzed at the last second- and third-trimester ultrasounds: intrauterine growth restriction, intra-abdominal bowel dilatation (IABD) adjusted for gestational age, extra-abdominal bowel dilatation (EABD) ≥25 mm, stomach dilatation, stomach herniation, perturbed mesenteric circulation, absence of bowel lumen and echogenic dilated bowel loops (EDBL). Results: Among 114 live births, 16 newborns had complex GS (14.0%). Death was seen in 16 cases (13.7%): 3 intrauterine fetal deaths, 9 complex GS and 4 simple GS. Second-trimester markers had limited predictive value. Third-trimester IABD, EABD, EDBL, absence of intestinal lumen and perturbed mesenteric circulation were statistically associated with complex GS and death. IABD was able to predict complex GS with a sensitivity of 50%, a specificity of 91%, a positive predictive value of 47% and a negative predictive value of 92%. Discussion: Third-trimester IABD adjusted for gestational age appears to be the prenatal ultrasound marker most strongly associated with adverse outcome in GS.