Biomedical subjects

L Nazarian

Publications and source records attributed to L Nazarian.

6 recordsLinked to original sources

PubMed1998

Color Doppler hemodynamic evaluation of flow to normal hip.

This study was aimed to quantitate hemodynamic flow to the normal proximal femur and to evaluate the effect of internal rotation on blood flow measurements in the hip to assess the capability of Doppler ultrasonography to detect a simulated ischemic situation. Forty hips in 20 adult healthy volunteers age 22 to 62 years (mean age, 39.5 years) were examined in the supine position in neutral position and during internal rotation (simulated ischemia). Medial and lateral circumflex arteries and veins were examined using standard ultrasound equipment with color and power Doppler capabilities. Arterial pulsatility index and maximal arterial and venous velocities were determined. Pulsatility index values in the medial circumflex artery were significantly (P < 0.05) changed during internal rotation of the leg. A drop in pulsatility index of more than 1.4 on the right and 2.2 on the left hip with respect to the normal neutral position was considered abnormal. The peak systolic velocity did not change significantly. The venous return showed a consistent increase in flow velocity during internal rotation, but this was borderline in terms of significance. Participants older than 40 years showed more prominent changes in pulsatility index during internal rotation. Repeat measurements performed in 10 hips showed only a 5% mean change in the pulsatility index values from the previous series of measurements. Changes in pulsatility index values occurred when flow in the proximal femur was compromised (internal rotation). These changes were particularly significant in the medial circumflex artery, which is the primary vascular supply of the femoral head and neck. Changes also were observed in the circumflex veins (velocity increased) on internal rotation; however, they were not statistically significant. Doppler ultrasonography of the medial circumflex artery is a potential tool for the assessment and follow-up of hip vascularity.

Adult↗

PubMed1996

How much does inferior capsular shift reduce shoulder volume?

The purpose of this study was to quantitate the effect of inferior capsular shift on shoulder volume. Four fresh frozen cadaveric shoulders were analyzed. Volume before and after shift was determined using 3 techniques: (1) Magnetic resonance imaging sequences were digitized to computer and analyzed for volume via a 35-mm camera using Cue 2 software. The capsule was delineated by contrast between light and dark regions. Volume was calculated by summing the total area of respective slices. (2) Ultrasound images, obtained after surgical exposure of the capsule, were digitized. Volume was calculated using the formula for a prolate ellipsoid. (3) An 18-gauge needle was used to inject and evacuate saline via an anterior approach. Quantity of aspirated fluid provided a direct measure of volume. Inferior capsular shift was performed. After the operation, measurements were repeated. Inferior capsular shift reduced volume in all shoulders with each technique. On average, inferior capsular shift reduced joint volume by 57 %). A measurable reduction in shoulder joint volume is an effect of capsular shift. This measurement may have clinical application if volume is an indicator of instability or laxity.

Cadaver↗

PubMed1996

Laparoscopic liver sonography: preliminary experience in liver metastases compared with CT portography.

This study evaluated the ability of laparoscopic ultrasonography to detect, localize, and characterize focal liver masses. Laparoscopic ultrasonography and CT portography of the liver were performed in 13 patients with known or suspected malignancy. Laparoscopic ultrasonography directly influenced surgical management in four (31%) cases; three by detection of small focal masses and one by exclusion of masses suspected on CT portography. Laparoscopic ultrasonography provided guidance for biopsy or added important anatomic information in three cases. Laparoscopic ultrasonography was complementary to CT portography but added no additional information in three cases, and it failed to provide any information in two cases. Laparoscopic ultrasonography was falsely negative in one case. In this preliminary series, laparoscopic ultrasonography assisted surgeons in critical decision-making by either providing important new information, clarifying questionable areas, or complementing CT portography.

Adult↗

PubMed1992

Increased ambulatory utilization in IPA plans among children receiving hyposensitization therapy.

There is concern that children with chronic conditions are less likely to be enrolled in managed care systems and that they may not receive optimal care. We studied the relationship between enrollment in an Independent Practice Association (IPA) plan and utilization of ambulatory services among children in a suburban pediatric practice with one mild chronic condition--those receiving hyposensitization therapy for allergic diseases. Ambulatory utilization by IPA patients (N = 102) was determined by medical chart review for one year before and one year after each patient switched from Blue Cross to IPA coverage. Blue Cross hyposensitization patients (N = 57) matched for age served as controls. Patients receiving hyposensitization were more likely to have enrolled in an IPA than those not receiving hyposensitization (70% vs 45%, p < .001). Before enrollment pre-IPA patients had 41% fewer well-child care (WCC) visits than Blue Cross patients (p < .01); both underutilized WCC visits according to established guidelines. Controlling for age and baseline utilization, we found a significant increase in WCC and acute care visits after IPA enrollment (p < .05), but no change in hyposensitization visits or referrals. In this setting, there was no evidence for reduced access to ambulatory services but rather evidence for improved utilization of primary care.

Adolescent↗

PubMed1990

The effect of independent practice association plans on use of pediatric ambulatory medical care in one group practice.

We compared the use of pediatric ambulatory medical care of 640 children who switched from a traditional Blue Cross plan to more comprehensive independent practice association plans with that of matched patients who remained with Blue Cross in one large, suburban pediatric practice in Rochester, NY. A quasi-experimental, retrospective cohort design was used. Use of pediatric ambulatory medical care by patients in the independent practice association plan and control patients was determined by medical chart review for 1 year before and 1 year after each patient's switch. During the baseline year, patients who would join the independent practice association plan already had 19% more acute-illness visits than control patients. During the second year, patients in the independent practice association plan averaged 42% more acute-illness visits, 22% more well child-care visits, 93% more chronic-illness visits, 27% more after-hours visits, 53% more weekend visits, 185% more laboratory studies, and 70% more referrals. The shift toward independent practice association plans in this open-market setting increased use of ambulatory medical care for pediatric patients.

Ambulatory Care↗

PubMed1976

Compliance with short-term antimicrobial therapy: some techniques that help.

The effect of two reminder devices on compliance with a ten-day antimicrobial prescription was investigated in a health center population. The reminders, a clock printed on the prescription label with appropriate times circled and a 5 X 7 inch bright red sticker to be posted at home, were compared to a control group. A total of 158 patients were interviewed at home on the ninth or tenth day of therapy, and compliance estimated by measuring the amount of remaining medication. For children, both reminders improved compliance about two-fold over controls. The findings suggest that (1) several simple reminder devices can be effective and (2) the nature of the patient population may be a more important influence on compliance than the relationship to a physician or the type of health care system. In addition, the study demonstrates the influence of the pharmacist on patients' medication-taking behavior.

Anti-Infective Agents↗