PubMed HealthSearch

Biomedical subjects

L Needleman

Publications and source records attributed to L Needleman.

At least 19 recordsLinked to original sources

Treatment of iatrogenic femoral artery injuries with ultrasound-guided compression.

Iatrogenic injuries of the groin are becoming more common after increasingly sophisticated vascular intervention. These injuries are accurately detected by duplex and color Doppler ultrasonography. Recent treatment of these lesions by ultrasound-guided compression repair (UGCR) has been described. During a 1-year period we identified 18 femoral artery injuries, including 17 pseudoaneurysms and one arteriovenous fistula. Three of the pseudoaneurysms thrombosed spontaneously before attempted treatment. The remaining 15 lesions underwent a trial of UGCR. Successful closure was accomplished in 10 patients (56%). Seven of these lesions were successfully treated during the initial session, and thrombosis was accomplished after repeat compression in three additional lesions. Three patients who were given anticoagulants had a failed UGCR, but their pseudoaneurysms thrombosed after administration of anticoagulants was discontinued. Two patients had failed UGCR and required operation. Seven (88%) of eight patients who were not given anticoagulants were successfully treated. In contrast only two (29%) of seven patients given therapeutic doses of anticoagulant medication were successfully treated by the technique. There was no statistical difference between mean pseudoaneurysm diameter, mean width and length of pseudoaneurysm neck, or depth of pseudoaneurysm neck from skin surface in patients in whom successful initial closure was achieved when compared with those patients in whom the initial attempt failed. UGCR is a safe, simple, noninvasive technique that can be used to treat many femoral artery injuries that traditionally were treated with surgery. The technique can be applied by any laboratory that has the necessary ultrasonography equipment and is currently the method of choice for treating uncomplicated iatrogenic femoral artery injuries at our institution.

Adult

Transnasal US of the esophagus: preliminary morphologic and function studies.

High-frequency catheter-based ultrasound (US) transducers can be inserted into the esophagus transnasally to evaluate esophageal wall structures. Studies were performed in two sheep esophagus specimens in vitro, in 17 healthy human subjects, and in 16 patients with esophageal abnormalities (eight with achalasia, four with scleroderma, three with esophageal carcinoma, and one with esophagitis). In the sheep specimens, endoluminal US delineated seven layers of the esophageal wall; these results correlated closely with histologic findings. Real-time US of the normal esophageal wall was performed during resting and swallowing. Muscles at the lower esophageal sphincter (LES) were shown to be thicker than muscles in the body of the esophagus. Thickening of the muscular layers at the LES in achalasia, dilated blood vessels within the submucosa in esophagitis, and fibrotic changes within the muscular layers in scleroderma were demonstrated. Extramural structures adjacent to the esophagus were also seen. These preliminary results suggest that transnasal esophageal US may become an important diagnostic tool in evaluation of the esophagus.

Adult

Can detection of the yolk sac in the first trimester be used to predict the outcome of pregnancy? A prospective sonographic study.

Recent reports have indicated that identification of the yolk sac should precede the detection of the embryo in a normal first-trimester sonographic examination and that failure to visualize a yolk sac strongly suggests an abnormal intrauterine pregnancy. A first-trimester prospective study was performed in 163 normal and 49 abnormal consecutive singleton gestations. All women were examined both abdominally and transvaginally, with pregnancy outcome determined by delivery of a normal infant or a spontaneous abortion. The yolk sac was analyzed in all patients in whom an embryo was not identified (n = 76). When the yolk sac was identified, the following was found: by the abdominal approach with the mean sac diameter (MSD) less than 27 mm (n = 15), nine gestations were normal and six were abnormal, and by the transvaginal approach with the MSD less than 18 mm (n = 13), seven gestations were normal and six were abnormal. The presence of a yolk sac was not consistently predictive of a normal early pregnancy. When the yolk sac was also not identified, the following was found: abdominally with the MSD less than 27 mm (n = 41), 19 gestations were normal and 22 were abnormal, and transvaginally with the MSD less than 18 mm (n = 11), six gestations were normal and five were abnormal. Absence of the yolk sac was not consistently predictive of a spontaneous abortion. When using the MSD range (20-27 mm abdominally and 7-16 mm transvaginally), over which the yolk sac but not the embryo should be identified sonographically, the yolk sac was again not consistently visualized. On abdominal sonograms, the yolk sac was present and absent in three and 10 patients, respectively, for both normal and abnormal pregnancies. On transvaginal sonograms, the yolk sac was present and absent in seven and five normal gestations and in six and four abnormal gestations, respectively. The results of this study suggest that detection of the yolk sac in the first trimester is not an early predictor of pregnancy outcome.

Female

Prospective comparison of vaginal and abdominal sonography in normal early pregnancy.

Vaginal and abdominal sonography were prospectively compared in 309 consecutive pregnancies of which 175 were normal. Two sonographic criteria of normal were analyzed: (1) the presence of an embryo compared with average gestational sac size and (2) the presence of embryonic cardiac activity compared with crown-rump length. Vaginally, 100% (160/160) of embryos were visualized when the average sac diameter was greater than or equal to 12 mm. Abdominally, an embryo was noted in 99.2% (123/124) of gestational sacs greater than or equal to 27 mm. Vaginal sonography revealed cardiac motion in all embryos of greater than or equal to 5 mm (149/149 cases); abdominal sonography revealed cardiac activity in 100% (132/132) of embryos with a crown-rump length of greater than or equal to 9 mm. One-third of normal embryos less than 5 mm crown-rump length did not demonstrate cardiac activity. The study demonstrates through objective comparison that vaginal sonography is superior to abdominal sonography for detection of an intrauterine embryo and its cardiac activity before 8 menstrual weeks. The diagnosis of embryonic demise should not be made by vaginal sonography in embryos measuring less than 5 mm crown-rump length without a heartbeat, and an empty gestational sac of less than 12 mm average diameter should not be diagnosed as blighted ovum by vaginal scans. In these cases follow-up vaginal sonography is suggested.

Abdomen

Detection of retained products of conception following spontaneous abortion in the first trimester.

A retrospective analysis was performed to determine whether ultrasound could reliably rule in or out retained products of conception (POC) in women after first-trimester spontaneous abortions (miscarriages). Ninety-seven first-trimester pregnancies with pathologically proven results from dilatation and curettage (D&C) were studied within 7 days of ultrasound examination (60% within 2 days), either by the abdominal or a combination of abdominal and vaginal approaches. Cases were eliminated if there was clinical evidence of a spontaneous evacuation of POC during the interval between the ultrasound and the D&C. POC were diagnosed only if chorionic villi were evident pathologically. The pertinent ultrasound findings were related to the endometrium (thickness, echogenicity, a gestational saclike structure or a space-occupying collection). The results indicated that ultrasound could correctly diagnose POC in all of the cases by detecting a gestational sac or collection (77 cases), or a thickened endometrium of greater than 5 mm (6 cases). Ultrasound was less reliable in ruling out retained POC. When only a thin endometrial stripe of less than 2 mm was present, there was little likelihood of having POC (1 of 7 cases) with a moderately thick endometrium of 2 to 5 mm not diagnostic. Vaginal ultrasound added little new information and failed to change the ultrasound interpretation.

Abortion, Incomplete

Anterior protrusion of retroperitoneal processes. A mimic of lesser sac or gastrohepatic masses.

The space between the left lobe of the liver and the lesser curvature of the stomach normally contains intraperitoneal structures. These include the gastrohepatic recess of the greater peritoneal cavity, the medial recess of the lesser sac and the interposed gastrohepatic ligament. An anterior protrusion of retroperitoneum can project into this space, dorsal to the posterior reflection of the medial compartment of the lesser sac. Tumors that extend into this fossa are anterior and medial to the fundic and upper body region of the stomach. These tumors may cause confusion regarding their origin if the radiologist is not aware of the existence of this retroperitoneal protrusion. Between 1982, and 1986, 183 patients with pancreatic cancer were hospitalized at our institution, 63 of whom had computed tomography (CT) scans of the abdomen. Four of these patients (6.3%) demonstrated direct tumor extension anterior to the stomach. During this same period, four large benign retroperitoneal tumors also exhibited this finding. Masses in the gastrohepatic interval between the liver and stomach can be extensions of retroperitoneal processes and should not be assumed to represent intraperitoneal involvement.

Diagnosis, Differential

Color Doppler imaging of the iliofemoral region.

Color Doppler imaging has been used to evaluate a variety of abnormalities in the iliofemoral region. This pictorial essay demonstrates how use of color Doppler techniques aids in the diagnoses of iliofemoral pseudoaneurysms, fluid collections, aneurysms, arteriovenous fistulas and malformations, venous thrombosis, vascular grafts, and soft-tissue masses including tumors and benign lymphadenopathy.

Color

Usefulness of a short femur in the in utero detection of skeletal dysplasias.

In 28 fetuses studied during a 4 1/2-year period, the initial femur was below 2 standard deviations (SDs) of the mean when compared with the biparietal diameter. These fetuses were considered at risk for skeletal dysplasias and were followed up. Studies were performed at a mean gestational age of 26.7 weeks (range, 15.3-41.0 weeks). Group 1 had a femur length 1-4 mm below the 2-SDs line (range, -2.0 to -4.0 SDs); no other abnormalities were detected. Interval examination of 12 femurs showed that 10 either remained shortened to the same degree or had a growth spurt. At birth, all subjects were healthy except one with mild growth retardation and one with a chromosomal abnormality. Of the two subjects that failed to continue normal growth, one was healthy and the other was a heterozygous achondroplastic dwarf. Group 2 had greater femoral shortness; all measurements were more than 5 mm below the 2-SD line (range, -4.3 to -31.0 SDs). All had fetal abnormalities and significant skeletal dysplasias. The authors conclude that the number of millimeters below the 2-SDs line is an accurate, easy criterion for evaluation of femoral length.

Bone Diseases, Developmental

Color Doppler artifact in anechoic regions.

For color Doppler imaging, several types of signal processing are employed in order to produce acceptable images of blood flow in blood vessels while suppressing color in moving solid tissue. The processing can produce an artifact in which color may arise from noise or from tissue motion and fill anechoic regions preferentially. This artifact may complicate the differentiation of areas with blood flow from anechoic regions without flow. By using four different color Doppler ultrasound units to image a tissue-equivalent phantom containing anechoic cylinders, artifactual color resulted when gain was raised sufficiently. This color was concentrated in anechoic regions of a gray-scale image that did not contain flow. In two instruments, this artifact was only observed when the transducer was vibrated, simulating tissue motion. In these instruments, the identification of low-frequency, high-amplitude Doppler signals is used to locate moving solid tissue and so suppress color in these regions. In the other two instruments, the presence of echoes within the image suppressed the assignment of color. With both types of processing, color may appear artifactually in echo-free regions without flow, such as fluid collections. Presence or absence of flow should be confirmed by Doppler spectral analysis. An understanding of the origin and appearance of artifactual color can prevent its occurrence from detracting from the usefulness of color Doppler imaging.

Aorta, Abdominal

Absence of end-diastolic umbilical artery blood flow predicts poor fetal outcome despite normal blood gases.

A case is reported in which the fetal acid-base status was assessed by means of cordocentesis in a fetus without end-diastolic umbilical artery blood flow. The absence of end-diastolic flow was not associated with acidosis or hypoxia. However, the fetal condition deteriorated 3 days later, which suggests that even with a normal fetal acid-base status, an extended margin of safety cannot be assumed with the absence of end-diastolic umbilical flow.

Acid-Base Equilibrium

Circle of Willis in newborns: color Doppler imaging of 53 healthy full-term infants.

To establish the usual pattern of flow in the circle of Willis in newborns, the authors scanned 53 healthy full-term infants within 3 days of birth with color Doppler imaging. All examinations were performed and images interpreted by the same experienced individuals. The basilar, internal carotid (ICA), and anterior and middle cerebral arteries were seen in all infants. Vertebral, posterior cerebral, superior cerebellar, and posterior communicating (PCoA) arteries were seen in most infants. PCoA flow was from the ICA toward the posterior cerebral artery in 73 (98.6%) of the 74 vessels that were seen. Flow in the anterior communicating artery was seen in six infants, indicating dependence of an anterior cerebral artery on contralateral ICA perfusion. Two pitfalls involving the distal portion of the ICA were noted: This vessel could be confused with the proximal portion of the anterior cerebral artery or cavernous sinus if real-time images were not interpreted carefully. Variant patterns of flow included tortuous basilar arteries (n = 2), reversed PCoA flow (n = 1), and inferior angulation of the proximal portions of the anterior cerebral arteries (n = 2). Color Doppler imaging allows a detailed analysis of the circle of Willis in newborns and detection of some anatomic variations.

Cerebral Arteries

Hand-held and automated sonomammography. Clinical role relative to X-ray mammography.

A retrospective analysis of 73 patients who had undergone X-ray mammography (XRM), automated sonomammography (ASM), and hand-held sonomammography (HSM) was performed to evaluate the clinical role of both types of sonomammography (SM) relative to XRM. The results were classified on the basis of mammographic and sonographic findings. Clinical and/or surgical proof was obtained in all 73 patients. The SM was complementary to XRM, depending on the radiographic breast density. When comparison was made between ASM (4.5 MHz) and the HSM (7.5 MHz), the pathologic condition was better identified by HSM in 86% of the cases. Moreover, in no cases was ASM better than HSM.

Adult

Neonatal brain: color Doppler imaging. Part I. Technique and vascular anatomy.

Color Doppler imaging (CDI) can demonstrate the relative direction and velocity of blood flow in color, superimposed on a conventional gray-scale ultrasound image that depicts stationary tissue. Twenty-five infants were studied with portable CDI in the coronal, sagittal, and axial planes. Bilateral antegrade flow was noted in the anterior, middle, and posterior cerebral arteries in all patients. Multiplanar CDI can image flow in the circle of Willis and its tributaries and branches.

Arteries

Neonatal brain: color Doppler imaging. Part II. Altered flow patterns from extracorporeal membrane oxygenation.

Extracorporeal membrane oxygenation (ECMO), a lifesaving procedure in neonates with severely impaired lung function, requires ligation of the right common carotid artery. In an investigation of the collateral pathways that maintain perfusion of the brain after right common carotid artery ligation, ten infants were studied with color Doppler imaging during and after ECMO. The circle of Willis was seen in all infants, and in every case there was retrograde flow in the distal internal carotid artery and the proximal (A1) segment of the anterior cerebral artery. Bilateral flow in the middle cerebral arteries and in distal branches of the anterior cerebral arteries was also seen, documenting flow to both cerebral hemispheres.

Carotid Arteries