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Biomedical subjects

H L Cohen

Publications and source records attributed to H L Cohen.

At least 91 records · Page 5Linked to original sources
PubMed1989

Complicated appendiceal inflammatory disease in children: pylephlebitis and liver abscess.

Five children with complicated appendiceal inflammatory disease are reported. They presented with nonspecific signs and symptoms, but three had liver abscess and two had inflammation of the portal vein. The inflamed portal vein may act as a conduit to the liver for bacteria, or it may become thrombosed and cause portal hypertension and hypersplenism. In one child, symptomatic portal hypertension developed 10 years after the initial disease. In children, an ultrasonic finding of a focal liver mass of low-to-mixed echogenicity or the presence of low-attenuation areas on computed tomographic scans should suggest the possibility of a hepatic abscess, and the radiologist has a major role in suggesting complicated inflammatory disease of the appendix as the cause. Similarly, when portal vein thrombosis or portal hypertension are found, the radiologist should consider complicated inflammatory disease of the appendix as the cause.

Adolescent↗
PubMed1989

Spontaneous perforation of the common bile duct in children.

The authors describe radiologic findings in five patients with spontaneous perforation of the common bile duct (a rare disorder). The patients were 5 weeks, 9 weeks, 3 months, 11 months, and 2 1/2 years old at presentation. The most common presenting complaints were jaundice and abdominal distention (due to ascites). Sonographic findings included ascites in three patients, a loculated fluid collection around the gallbladder in two patients, and both in one patient. The biliary tree was undilated in all patients. Results of hepatobiliary scintigraphy definitely demonstrated that intraperitoneal fluid originated from the biliary tract. Intraoperative cholangiography was used to confirm the diagnosis at surgery. All children were successfully treated with surgery. Recognition of these findings on sonograms and subsequent confirmation with scintigraphy are important to prevent delays in diagnosis of a potentially fatal condition.

Child, Preschool↗
PubMed1989

Calcification of the ductus venosus: a cause of right upper quadrant calcification in the newborn.

The authors report three cases of ductus venosus calcification as an additional cause of vascular liver calcification in the newborn. All three infants had umbilical venous catheters. The calcification may be caused by extravasated fluids given through the catheter or by local trauma due to catheter insertion. An obliquely oriented, paravertebral "tram-track" calcification in the right upper quadrant, particularly in a premature infant with a history of umbilical venous catheterization, should suggest the diagnosis of calcified ductus venosus.

Calcinosis↗
PubMed1989

Ultrasound of the pediatric upper gastrointestinal tract.

Fluid aided ultrasound examination of the neonatal upper gastrointestinal tract has been highly successful in the evaluation of hypertrophic pyloric stenosis. It can diagnose midgut volvulus. It has proved helpful in triaging significant gastroesophageal reflux. We have used this technique in evaluation of malrotation and in the diagnosis of duodenal atresias and stenoses. Its usefulness will be properly assessed by further investigation and diagnostic experience. If it merely saves radiation when used as a triaging tool, it serves a significant purpose. If it can prove a primary diagnostic modality, patients can only benefit.

Gastrointestinal Diseases↗
PubMed1988

Cardiovascular function is altered by picomole injections of glutamate into rat medulla.

Local neural circuitry in the nucleus tractus solitarius (NTS) involved in cardiovascular control was studied by injecting nanoliter volumes of excitatory amino acids into the structure. Experiments were performed on urethane-anesthetized, artificially ventilated rats. Multibarrel micropipettes were used for pressure ejection of drugs or a dye for marking ejection sites. Ejected volumes, ranging from 200 pl to 25 nl, were directly monitored for every injection. Injections of as little as 200 fmol of L-glutamate in 200 pl into the medial and lateral NTS region rostral to the obex elicited marked, site-specific decreases in arterial pressure and heart rate. The majority of these responses were eliminated by blockade of parasympathetic and sympathetic neural outflow. At sites caudal to obex, in the commissural region of the NTS, L-glutamate injections produced marked elevations in heart rate and arterial pressure which were sympathetically mediated. Responses to L-glutamate were attenuated by concurrent injection of glutamic acid diethyl ester and DL-2-amino-4-phosphonobutyrate, or lidocaine. These results indicate a heterogeneity in the spatial organization of brain-stem circuitry underlying cardiovascular control that has not been previously described.

Animals↗
PubMed1987

Age-related changes in power spectra of efferent phrenic activity in the piglet.

Power spectral analysis of phrenic nerve discharge in neonatal swine revealed the presence of both high-frequency oscillations (HFO) (95-150 Hz) and medium-frequency oscillations (MFO) (15-35 Hz). The HFO was shown to be age-related; the MFO was not. The data indicated that at least one manifestation of maturation of the respiratory rhythm generator is the increase with age of the frequency of the HFO.

Aging↗
PubMed1987

Diagnostic sonography of the fetal genitourinary tract.

Fetal diagnosis has vastly improved over the last decade. Ultrasound has become the imaging modality of choice. As real-time equipment has improved technologically, the ability to deduce subtle abnormalities has greatly increased. The fetal genitourinary tract may be evaluated for renal dysplasias, anomalies, or obstruction. Points of obstruction and, at times, the exact cause of obstruction may be deduced. Abnormalities of the ureter, bladder, urethra, scrotum, or reproductive system can be detected. Early diagnosis allows for proper individual or family counseling for hereditable disorders and chromosomal abnormalities. The perinatology team can be alerted to an abnormality that may require early neonatal surgical or medical intervention. Early treatment can prevent significant deterioration of renal function. The possibilities of prenatal intervention may be considered.

Amniotic Fluid↗
PubMed1987

Pediatric urosonography: an update.

Improvements in ultrasound technology have brought marked changes in the work-up of common pediatric clinical problems. This paper reviews the impact of ultrasound on genitourinary problems in infants and children.

Adrenal Gland Neoplasms↗
PubMed1987

Neonatal duodenum: fluid-aided US examination.

In 261 infants with vomiting, 11 duodenal abnormalities were diagnosed with fluid-aided ultrasound (US). These abnormalities included duodenal obstruction, malrotation with and without associated volvulus, incomplete rotation, and duodenal stenosis. US was the initial modality used in the evaluation of vomiting in these neonates and young infants. The overall sensitivity and specificity of fluid-aided US evaluation of duodenal abnormalities were 100% and 99%, respectively. (Workup bias limits the reliability of these figures.) Fluid-aided US examination of the stomach and duodenum provided a dynamic view of duodenal rotation and anatomy, and at the very least provided a method of triaging those infants who may require surgery, upper gastrointestinal series, or follow-up US to make a definitive diagnosis.

Duodenal Obstruction↗
PubMed1987

Ultrasonic "double track" sign in hypertrophic pyloric stenosis.

Ultrasound has been used in the diagnosis of hypertrophic pyloric stenosis since the first reports of its use with contact B mode scanners. Real-time imaging has allowed measurements of pyloric diameter, length, and muscle wall thickness. Wall thickness measurements taken with the pylorus in longitudinal (elongated) view improve diagnostic accuracy. Fluid aided real-time examination of 10 cases showed the ultrasound equivalent of the "double track" sign. This finding is the result of pyloric fluid compressed into smaller tracks as it is impinged upon circumferentially by the thickened circular muscle. This sign, previously seen in barium studies, although nonspecific, may prove to be a sensitive diagnostic criterion.

Female↗
PubMed1986

Renal candidiasis of the infant: ultrasound evaluation.

Sonographic diagnosis of 3 cases of renal candidiasis led to early diagnosis and treatment. Echogenic densities within a dilated pyelocalyceal system appeared to be the classic finding for obstructing candidal bezoars or candidal pyonephrosis in the premature neonate. Sonography was useful in guiding diagnostic and therapeutic percutaneous nephrostomies of very premature (900 and 750 g) infants. The ultrasonic findings of moderate echogenicity within dilated collecting systems in premature infants suggest pyonephrosis. Candidiasis should be considered as a prime cause.

Candidiasis↗
PubMed1986

Age-related responses to stimulation of cardiopulmonary receptors in swine.

Cardiovascular responses to stimulation of cardiopulmonary receptors were evaluated in standard breed developing swine (1-2 days, 1-2 wk, and 2 mo of age) and sexually mature miniswine anesthetized with 0.25-0.50% halothane in O2. Cryptenamine, a mixture of veratrum viride alkaloids (VVA), was administered as right atrial or left ventricular bolus injections in doses of 5-20 micrograms/kg. In developing swine, mean aortic pressure (AoP) decreased after 10-20 micrograms/kg VVA in 1- to 2-wk olds and after 5-20 micrograms/kg VVA in 2-mo olds. Bradycardia was always elicited. Renal (Ren) and femoral (Fem) vasodilation occurred in the 1- to 2-wk-old and 2-mo-old groups after 5-20 micrograms/kg VVA. Mesenteric (Mes) vasodilation was elicited with 10-20 micrograms/kg VVA in the 1- to 2-wk-old group and with 5-20 micrograms/kg VVA in 2-mo olds. In the 1- to 2-day-old group, VVA did not significantly alter Ren, Fem, and Mes vascular resistance. In mature miniswine, 20 micrograms/kg VVA elicited decreases in AoP and heart rate that were similar in magnitude to responses obtained with only 5 micrograms/kg VVA in dogs. Cardiovascular responses to VVA were abolished after bilateral vagotomy but were not altered after denervation of the carotid sinuses. The results indicate postnatal maturation of the Bezold-Jarisch reflex in swine.

Aging↗