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Biomedical subjects

D Jaramillo

Publications and source records attributed to D Jaramillo.

At least 73 records · Page 4Linked to original sources
PubMed1992

Voiding cystourethrography in children: value of digital fluoroscopy in reducing radiation dose.

Voiding cystourethrography is a commonly used fluoroscopic procedure in children that can directly irradiate the gonads. As a consequence, much attention has been given to reducing the dose of radiation received during the procedure. A digital fluoroscope, especially adapted for use in children, was evaluated for potential reduction of the dose of radiation during the procedure. Entrance and midplane doses were calculated on child-sized phantoms by using the digital fluoroscope, digital spot films, and 105-mm spot films. Subsequently, data were collected on 47 children, grouped by ages (neonate to 1 year, 1-5 years, and 5-7 years), in whom voiding cystourethrography was performed by using the same exposure factors as those for the phantoms. On the basis of the exposure doses for the phantoms and recorded clinical peak kilovoltages, milliamperes, milliseconds, and fluoroscopic time, average skin and ovarian doses were calculated for each group of children. These doses were compared with previously reported doses for fluoroscopic and radionuclide voiding cystourethrography. Results of line-pair resolution studies for the digital spot films and 105-mm spot films were similar. Images from the digital device and 105-mm images obtained on a conventional fluoroscope were considered equally adequate for clinical decision making. The average midplane and skin doses with digital spot films for children less than 5 years old were equal to or less than 0.66 and 2.37 mGy, respectively, as opposed to 1.37 and 5.32 mGy with the 105-mm spot films. Previously reported ovarian doses range from 2.52 to 10.0 mGy for fluoroscopic voiding cystourethrography and from 0.04 to 0.05 mGy for radionuclide voiding cystourethrography. The use of digital spot films reduced dose approximately 50% compared with 105-mm spot films; the ovarian dose was 0.62 mGy greater than that for radionuclide voiding cystourethrography.

Child↗
PubMed1992

Cartilaginous epiphysis and growth plate: normal and abnormal MR imaging findings.

The cartilaginous structures at the ends of growing bones constitute the "growth mechanism." These structures are not visible on radiographs, but they can be seen with MR imaging. Improved definition of cartilaginous abnormalities by MR imaging may permit earlier detection and treatment of these disorders and thus prevent bone deformity. This pictorial essay contains examples of normal and abnormal growth cartilage as seen with MR imaging. The indications for MR imaging in the evaluation of certain growth disorders are discussed, and the usefulness of MR imaging in certain clinical situations in which the role of this technique is still evolving is illustrated.

Bone Diseases↗
PubMed1991

Coexisting nephrolithiasis and cholelithiasis in premature infants.

Though the coexistence of nephrolithiasis and cholelithiasis in premature infants is extremely rare, we report four patients seen in a two year period. All patients weighed less than 1100 grams at birth, developed severe bronchopulmonary dysplasia, and all had Grade III or IV bilateral intraventricular hemorrhages. All four infants received prolonged furosemide therapy lasting at least 28 consecutive days. The renal stones disappeared in all four upon cessation of therapy, while in none have the gallstones disappeared after a mean follow-up period of 13 months. Ultrasound was superior in identifying and monitoring these stones. Their presence resulted in manipulating diuretic therapy which then was shown to limit renal and possibly biliary complications.

Bronchopulmonary Dysplasia↗
PubMed1991

Videofluoroscopic analysis of the infant swallow.

A better understanding of the abnormal infant swallowing mechanism requires better knowledge of the normal infant swallow. Twenty-one full-term infants under six months of age were examined using videofluoroscopy of the swallowing portion of upper gastrointestinal examinations. Components of the oral and pharyngeal stages of swallowing were evaluated. Results showed high reliability between two raters in obtaining measurement data. There was variability in suck and oral transit time, which was correlated to the number of sucks per swallow. All infants appeared to move their tongue in a "stripping" motion, and collected the material in various sites in the oral cavity or oropharynx before initiation of the swallow. The incidence of nasopharyngeal reflux was low (9.5%). The majority of infants demonstrated a slight residue in their valleculae and hesitation in the cervical esophagus. These findings indicate that videofluoroscopy provides an objective and systematic method for analyzing the infant swallowing mechanism.

Deglutition↗
PubMed1991

Bone marrow: ultrasmall superparamagnetic iron oxide for MR imaging.

An ultrasmall superparamagnetic iron oxide (USPIO) preparation was evaluated as a potential intravenous contrast agent for magnetic resonance (MR) imaging of bone marrow. One hour after administration of USPIO (40, 80, and 160 mumols of iron per kilogram body weight) in rats and rabbits, T1 and T2 relaxation times were, respectively, approximately 30%, 50%, and 65% lower than precontrast relaxation times. Maximum decrease in relaxation times of marrow occurred within 1-24 hours after intravenous administration; thereafter, relaxation times slowly returned to normal within 7 days. In vivo MR imaging of rabbits and rats confirmed that USPIO decreases signal intensity of red and yellow marrow. The decrease was most marked with gradient echo pulse sequences. An animal model of intramedullary tumor demonstrated the potential of USPIO to enable differentiation between tumor and normal red marrow. USPIO-enhanced MR imaging improves detection of smaller tumors and allows differentiation of tumor deposits from islands of hyperplastic or normal red marrow.

Animals↗
PubMed1991

Epiphyseal marrow in infancy: MR imaging.

Hypointense epiphyseal marrow on T1-weighted magnetic resonance images often suggests disease. To determine whether hypointense marrow sometimes represents normal red marrow in a recently ossified epiphyseal center, the authors studied 38 infants without known marrow disease. Patients with hypointense epiphyseal marrow on T1-weighted images were younger (3.9 months +/- 3.2) than those with hyperintense marrow (9.6 months +/- 3.9) (P less than .001). T1-weighted imaging and histologic correlation were also performed in animals. The signal was hypointense and the marrow was red in the epiphyseal centers of all newborn animals, while all 6-week-old animals had hyperintense signal and yellow marrow. The authors conclude that hypointense marrow on T1-weighted images represents normal red marrow in a recently formed ossification center in newborn rabbits and lambs, and the same is probably true in humans. Epiphyseal marrow becomes hyperintense within a few months of development of the secondary center of ossification.

Animals↗
PubMed1990

Familial superior mesenteric artery syndrome.

Five members of a family of eight, including the father and four daughters, presented with symptoms previously attributed to the superior mesenteric artery syndrome. The four daughters also had radiographic studies supporting that diagnosis. This familial clustering raises the possibility of a genetic predisposition to this symptom and radiographic complex.

Adolescent↗
PubMed1990

Posttraumatic growth-plate abnormalities: MR imaging of bony-bridge formation in rabbits.

The formation of a bony bridge across the growth plate was studied with magnetic resonance (MR) imaging, tomography, and histologic examination in 12 rabbits. Histologic studies performed 0-8 weeks after the creation of a defect in the physis demonstrated transphyseal bone formation with no evidence of cartilage repair. Gadolinium enhancement indicated the development of vascularity through the plate, which preceded the formation of a bony bridge. Enhancement was faint at 4 days after surgery, was inhomogeneous at 1 week, was maximal at 2 weeks, and decreased at 3 weeks and beyond as the lesion was replaced by bone. A dark rim representing bone deposition at the periphery of the lesion was seen at 2 weeks. At 4 weeks and beyond, the bridge was seen as a dark band of dense bone or as a wider area that was isointense with adjacent fatty marrow. Abnormality in the cartilage and development of transphyseal vascularity, which precede the formation of a bony bridge after trauma, can be detected with MR imaging.

Animals↗
PubMed1990

The cloacal malformation: radiologic findings and imaging recommendations.

The imaging studies and records of 65 patients with the cloacal malformation seen from 1969 to 1989 were reviewed. The malformations were described according to cloacal configuration (urethral, vaginal), type of urinary-cloacal communication (urethral, vesical), and level of rectal communication (vaginal, cloacal, vesical, other). Lower urinary tract abnormalities were frequent (reflux, ureteral ectopia, bladder diverticula, bladder duplication, urachal remnants, urethral duplication), as were genital abnormalities (uterine duplication, vaginal duplication, uterine atresia, vaginal atresia), abnormalities of the bony pelvis (partial sacral agenesis, pubic diastasis), and renal abnormalities (agenesis, obstruction, horseshoe kidney). Contrast material studies of the cloaca and the distal limb of the colostomy with fluoroscopy in various projections were essential for diagnosis. Voiding cystourethrography was important for detecting vesicoureteric reflux. Sonography was of limited value for evaluation of the malformation but was valuable for imaging the kidneys. MR imaging revealed that spinal cord abnormalities cannot be predicted based on the appearance of the lumbosacral spine and are more common than previously thought.

Abnormalities, Multiple↗
PubMed1990

MR imaging of fractures of the growth plate.

In order to assess whether MR imaging could be used to evaluate posttraumatic abnormalities of the growth plate cartilage, 28 MR imaging examinations of 26 physeal fractures were performed from 4 days to 2 years after injury. Twelve patients were studied within 6 months of the fracture. MR imaging changed the Salter-Harris classification in six. Interruption of the growth plate detected on T2-weighted images was associated with subsequent growth anomaly in six of eight patients. Horizontal fracture of the physis without interruption was associated with growth disturbance in only one of four patients. Sixteen growth plates were studied beyond 6 months after injury. Twelve had physeal bars and abnormal growth. Of four patients without physeal abnormality on MR imaging, two had normal growth and two had mild deformity. Our results show that MR imaging defects abnormalities in the cartilage that are associated with subsequent growth disturbances and provides accurate mapping of physeal bridging and associated growth abnormalities that have already occurred.

Adolescent↗
PubMed1989

Sonography of testicular microlithiasis.

The sonographic appearance of testicular microlithiasis detected in a patient presenting with torsion is described. A "speckled" pattern of multiple, tiny bright echoes is produced by calcific concretions in the seminiferous tubules and seems to be characteristic of microlithiasis. Although this condition is not treatable, it should be recognized because it is often associated with extratesticular abnormalities and can obscure superimposed testicular disease.

Adolescent↗
PubMed1989

Apparent association between thymic cysts and prior thoracotomy.

Three male subjects, aged 8 months to 18 years, who had previously undergone thoracic surgery, developed mediastinal thymic cysts. Two cysts, both multilocular, were shown by plain radiography and computed tomography, and one was found incidentally during cardiac surgery. These three cysts constitute 15% of the 20 thymic cysts removed surgically or found at autopsy at the authors' hospital in the past 27 years. These cases and three previously reported cases in male adolescents and adults suggest that some thymic cysts are related to trauma during surgery.

Adolescent↗
PubMed1988

South American pemphigus foliaceus: study of an epidemic in El Bagre and Nechi, Colombia 1982 to 1986.

Between 1982 and 1986 we have had the chance to study 21 patients with pemphigus foliaceus of the 'fogo selvagem' type. The patients came from El Bagre and Nechi, rural areas of Colombia with some gold mining. This is the first outbreak of South American pemphigus foliaceus reported in Colombia. The majority of the patients were mestizo men, who worked as farmers or miners or both, with an average age of 44. Five patients were relatives. Eleven patients (52%) had mild disease, three (14%) moderate disease and seven (33%) severe disease. During hospitalization, three patients died due to complications or as a result of immunosuppressive treatment. Of the remaining 18 patients, 10 were in remission with treatment, one was in remission without treatment, while no information was available on the remaining seven.

Adult↗
PubMed1987

Pulmonary arterial hypertension as a manifestation of lupus erythematosus.

We present five patients with systemic lupus erythematosus (SLE) who developed pulmonary arterial hypertension and cor pulmonale in the course of their disease. The clinical features, as well as, the radiological manifestations of this rare manifestation of SLE are discussed. A vasculitic process is the most likely cause of this complication. Therapy is ineffective and the prognosis is poor.

Adult↗