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J Alarcon

Publications and source records attributed to J Alarcon.

11 recordsLinked to original sources
PubMed2000

Fetal MRI in the evaluation of intrauterine myelomeningocele.

BACKGROUND: Accurate fetal imaging is essential to the practice of maternal-fetal medicine. While ultrasonography has been the traditional mainstay of fetal imaging, its ability to resolve critical features of central nervous system (CNS) anatomy remains limited. As interest in intrauterine therapy for myelomeningocele has increased, so has the need for more accurate, noninvasive imaging of the CNS. Fetal magnetic resonance imaging (MRI) promises to fill the gap left by ultrasound. METHODS: Thirty-seven MRI scans of fetuses previously diagnosed with myelomeningocele were reviewed by 2 neuroradiologists. The ability of fetal MRI to resolve the commonest CNS stigmata of spina bifida, and the incidence and extent of interobserver error, was assessed. In 4 cases, postnatal MRIs were also available. These were compared to the corresponding fetal studies. RESULTS: The imaging quality with the technique used in this study was excellent, even without the use of maternal or fetal sedation. There were no complications, and the imaging times were minimal. Interobserver error was minimal with respect to the evaluation of ventricular dilatation and hindbrain herniation, but moderate in the description and location of the spinal lesion. As had previously been documented with ultrasonography, a reduction was seen in hindbrain herniation when comparing pre- and postnatal MRIs. CONCLUSION: It is concluded that fetal MRI is an effective, noninvasive means of assessing fetal CNS anatomy. Its ability to resolve posterior fossa anatomy is superior to ultrasonography while, with respect to the evaluation of hydrocephalus and the level and nature of the spinal lesion, it may be equivalent to inferior. Inclusion of the fetal MRI into the standard diagnostic armamentarium will probably await the next major advance in speed and resolution. It is conceivable that, with further advances, MRI might supplant ultrasonography as the diagnostic tool of choice for evaluation of fetal anomalies including myelomeningocele.

Cranial Fossa, Posterior↗
PubMed1998

Inconsistency of emergency department triage. Emergency Department Operations Research Working Group.

STUDY OBJECTIVE: To measure the interrater and intrarater agreement of existing emergency department triage systems. METHODS: This 2-phase experimental study of triage nurses' and EMTs ratings for 5 scripted patient scenarios used in-person interviews and follow-up written surveys. RESULTS: Eighty-seven participants (> 90% of those eligible) with 55 (63%) completed both phases of the study. Interrater agreement on triage category was poor (kappa = .347 overall). Only 13 of 55 (24%) participants rated the 5 cases the same severity in both phases; Kendall correlation (iota-B) comparing phases 1 and 2 varied from .145 to .554. Estimates of admission probability varied widely. Estimates of the appropriate time to physician evaluation (from immediate to 24 hours) was often incongruous with severity ratings (e.g., 54% of those participants rating a case the lowest severity recommended evaluation within 8 hours). There was good agreement on estimated need for an ED monitored bed or diagnostic studies. CONCLUSION: Triage assessments (both interrater and intrarater) by experienced personnel are inconsistent using these 5 standardized patient scenarios. These results challenge the reliability of current ED triage practice.

Emergency Medical Technicians↗
PubMed1996

Diurnal and weekly variation of tardive dyskinesia measured by digital image processing.

The diurnal and weekly variability of tardive dyskinesia (TD) was assessed instrumentally by digital image processing. Weekly assessments were obtained in ten patients over a 6-week period. In six of the ten patients, assessments were obtained four times over a single 12-h period. Results indicate that TD movements measured by instrumental assessment vary from week to week and throughout the day. Factors that appear to have affected the variability were changes in medications and the time of day when the assessments were conducted.

Adult↗
PubMed1996

The epidemiology of HIV-1 infection in Peru, 1986-1990.

OBJECTIVE: To determine the extent of the HIV-1 epidemic in Peru. DESIGN: Part of a national serosurvey in Peru. METHODS: Between January 1986 and December 1990, 140,976 serum samples were tested for HIV-1 antibody. RESULTS: HIV-1 antibody was found in a high percentage of serum samples provided by 4300 homosexual men (26%), 2204 male sexually transmitted disease patients (10%), 145 drug users (13%), 269 hemophiliacs (10%), and 146 unlicensed female prostitutes (10%). In addition, the prevalence of HIV-1 infection increased substantially among these groups between the beginning and end of the survey period. A low but rising prevalence of HIV-1 antibody was found during this period among serum samples provided by 83,526 blood donors and 11,101 military personnel:total period prevalence, 0.25 and 0.32%, respectively. CONCLUSION: These data indicate that HIV-1 infection is epidemic in Peru among groups at high risk of sexually and parenterally transmitted diseases, and that the risk of infection appears to be low but possibly increasing among the general population.

Disease Outbreaks↗
PubMed1995

Insecticide-impregnated bed nets for malaria control: varying experiences from Ecuador, Colombia, and Peru concerning acceptability and effectiveness.

Between 1991 and 1994, an intervention program with permethrin- and lambdacyhalothrin-impregnated bed nets was carried out over a period of nine months in each of five endemic, malarious areas of Ecuador, Peru, and Colombia. This program was evaluated through household surveys, blood sampling, in-depth longitudinal studies, and entomologic analysis. Eighty-four communities (including approximately 35,000 individuals) were paired according to malaria incidence, size, and coverage with bed nets and then randomly allocated to intervention and control groups. The results showed that peoples' acceptance of the measure was related to their perception of an immediate protective effect against insects. The effectiveness of the bed nets, measured as a reduction of malaria incidence in intervention communities as against control communities, showed large variations between and within the study areas. The protective efficacy varied between 0% and 70% when looking only at the postintervention differences between intervention and control groups. The average protection was 40.8% when considering a four-month incidence of clinical malaria attacks and 28.3% when considering a two-week malaria incidence. Important factors for the success of the bed net program were insect susceptibility to pyrethroids, high coverage with impregnated bed nets, high malaria incidence, good community participation, high mosquito densities when people go to bed, and a high proportion of Plasmodium falciparum. In one area, where DDT spraying in the control communities was executed, the effectiveness of bed net impregnation was slightly better than that of spraying.

Adolescent↗
PubMed1991

Hepatic metastases: CT versus MR imaging at 1.5T.

A prospective multi-institutional study was performed to compare the sensitivity of computed tomography (CT) and high-field magnetic resonance (MR) imaging (1.5T) in the detection of hepatic metastases. T1-weighted and 72-weighted spin-echo (SE) MR images were compared with noncontrast, dynamic, and delayed CT. Sixty-nine oncology patients were studied. Noncontrast CT showed an overall sensitivity of 57%, dynamic CT 71%, delayed CT 72%, T1-weighted SE MR 47%, and T2-weighted SE MR 78%. Although there was no statistically significant (p less than 0.05) difference among dynamic CT, delayed CT, and T2-weighted SE MR, these three methods were significantly more sensitive (p less than 0.005) than noncontrast CT or T1-weighted SE MR. T2-weighted SE MR was significantly more sensitive (p less than 0.006) than CT or T1-weighted SE MR in the detection of small (less than 1 cm) lesions. CT was more sensitive in the detection of extrahepatic disease. These data confirm the superiority of T2-weighted SE over T1-weighted SE pulse sequences at 1.5T.

Adult↗
PubMed1988

Postoperative pulmonary complications: general anesthesia with postoperative parenteral morphine compared with epidural analgesia.

In a prospective study, patients undergoing abdominal cancer surgery were randomly allocated to receive either general anesthesia with fentanyl intravenously and postoperative analgesia with parenteral morphine (GA group) or general anesthesia combined with epidural bupivacaine and epidural morphine for postoperative pain relief (EP group). Analgesia was tested on a visual pain scale. Pulmonary complications were evaluated by clinical complications, blood gas analysis, x-ray film changes, and pulmonary volumes (vital capacity, forced expiratory volume in 1 second). Measurements were performed on the day before the operation and on the first 5 postoperative days. In the EP group the pain relief was significantly better on the first day (p less than 0.03). Whatever the criteria used, the rates of pulmonary complications were similar in the two groups: clinical complications 21% versus 26%, radiologic complications 50% versus 64% for GA and EP groups, respectively. Postoperative PaO2 and spirometric values were similar in the two groups. Postoperative epidural analgesia may improve the patient's comfort but does not decrease the incidence of pulmonary complications.

Abdomen↗
PubMed1979

[Not Available].

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History of Pharmacy↗
PubMedDate not supplied

Adenocarcinoma of the colon and rectum: a review of surgical treatment in 302 patients.

A retrospective study of 302 patients who underwent surgical treatment for colorectal carcinoma from 1952 to 1971 is presented. Resectability rate was 93.7 per cent. Operative mortality rate was 5 per cent. Complications were recorded in 12 per cent of cases. Recurrence at the anastomotic line occurred in 3.31 per cent. The actuarial five-year survival rate was 44.2 per cent for all types of cancer. The "no-touch" technique utilized after 1968 resulted in increased survival of patients who had Dukes' B and C cancers.

Adenocarcinoma↗