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Y Itzchak

Publications and source records attributed to Y Itzchak.

At least 37 records · Page 2Linked to original sources
PubMed1998

CT angiography of superior mesenteric artery syndrome.

OBJECTIVE: Our purpose was to describe the use of CT angiography and three-dimensional (3D) reconstruction in the diagnosis of superior mesenteric artery syndrome in three patients. CONCLUSION: CT angiography combined with 3D reconstructions is a noninvasive technique that may have a complementary diagnostic role similar to that of angiography in patients with a classic clinical presentation suggestive of superior mesenteric artery syndrome. CT angiography combined with 3D reconstructions should be considered in patients who might otherwise require angiography.

Adult↗
PubMed1998

Virtual bronchoscopy in children: early clinical experience.

OBJECTIVE: Virtual bronchoscopy is a new noninvasive technique that provides an internal view of the tracheobronchial tree. The purpose of our study was to assess the role of this technique as compared with fiberoptic bronchoscopy in the evaluation of suspected compression or narrowing of the trachea and main bronchi in children. CONCLUSION: Preliminary results suggest that virtual bronchoscopy may have a useful complementary role to fiberoptic bronchoscopy in evaluation of the tracheobronchial tree of children.

Adolescent↗
PubMed1998

A sequence of object-processing stages revealed by fMRI in the human occipital lobe.

Functional magnetic resonance imaging was used in combined functional selectivity and retinotopic mapping tests to reveal object-related visual areas in the human occipital lobe. Subjects were tested with right, left, up, or down hemivisual field stimuli which were composed of images of natural objects (faces, animals, man-made objects) or highly scrambled (1,024 elements) versions of the same images. In a similar fashion, the horizontal and vertical meridians were mapped to define the borders of these areas. Concurrently, the same cortical sites were tested for their sensitivity to image-scrambling by varying the number of scrambled picture fragments (from 16-1,024) while controlling for the Fourier power spectrum of the pictures and their order of presentation. Our results reveal a stagewise decrease in retinotopy and an increase in sensitivity to image-scrambling. Three main distinct foci were found in the human visual object recognition pathway (Ungerleider and Haxby [1994]: Curr Opin Neurobiol 4:157-165): 1) Retinotopic primary areas V1-3 did not exhibit significant reduction in activation to scrambled images. 2) Areas V4v (Sereno et al., [1995]: Science 268:889-893) and V3A (De Yoe et al., [1996]: Proc Natl Acad Sci USA 93:2382-2386; Tootell et al., [1997]: J Neurosci 71:7060-7078) manifested both retinotopy and decreased activation to highly scrambled images. 3) The essentially nonretinotopic lateral occipital complex (LO) (Malach et al., [1995]: Proc Natl Acad Sci USA 92:8135-8139; Tootell et al., [1996]: Trends Neurosci 19:481-489) exhibited the highest sensitivity to image scrambling, and appears to be homologous to macaque the infero-temporal (IT) cortex (Tanaka [1996]: Curr Opin Neurobiol 523-529). Breaking the images into 64, 256, or 1,024 randomly scrambled blocks reduced activation in LO voxels. However, many LO voxels remained significantly activated by mildly scrambled images (16 blocks). These results suggest the existence of object-fragment representation in LO.

Adult↗
PubMed1998

Ultrasound prenatal diagnosis of the Nail-Patella syndrome.

The Nail-Patella syndrome (NPS) is an autosomal dominant connective-tissue disorder characterized by the absence or hypoplasia of the nails and patella, posterior illiac horns, elbow deformities, congenital nephropathy cervical ribs and eye problems. The presence of the posterior iliac horns is pathognomonic and have been observed in more than 80 per cent of cases. In this report, we present the first case of prenatal diagnosis of NPS by ultrasound. The possible kidney involvement, combined with other, milder, complications make the prenatal diagnosis of this syndrome worthwhile.

Adult↗
PubMed1997

In vivo 23Na NMR studies of myotonic dystrophy.

Myotonic dystrophy is an inherited multi-system disease. Its pathophysiology leading to muscle malfunction and damage is not well understood. 23Na NMR spectroscopy was applied here for an in vivo comparative study of the calf muscles of 7 myotonic dystrophy patients at various stages of the disease and 11 healthy volunteers. Both the total sodium content, expressed as the ratio of the 23Na and 1H water signals, and the fast transverse relaxation time, T2f, determined from the triple quantum-filtered spectra, increased in correlation with the severity of the disease. The results demonstrate that 23Na NMR enables the quantitation of myotonic dystrophy progression.

Adolescent↗
PubMed1997

Coronary calcium measurements by double helical computed tomography. Using the average instead of peak density algorithm improves reproducibility.

RATIONALE AND OBJECTIVES: Coronary calcium (CC) measured by fast computed tomography (CT) was proposed recently as a noninvasive method of monitoring the coronary atherosclerotic process. Assessment of the reproducibility of CC measurements (mainly interstudy variability) is essential for consistent interpretation of serial studies. METHODS: The authors scanned 74 patients (50 men and 24 women) twice on the same day to determine the interstudy variability of a new scoring algorithm, using the average instead of conventional peak CT density values. RESULTS: Nineteen patients had no calcium on either scan. In the remaining 55 patients, interstudy variability was decreased by 31% using the average algorithm (32%-23%; P < 0.001). CONCLUSIONS: Using the average instead of conventional peak density score provides better reproducible measurements of calcium by double helical CT.

Adult↗
PubMed1997

Coronary artery calcification in women with syndrome X: usefulness of double-helical CT for detection.

PURPOSE: To determine the usefulness of double-helical computed tomography (CT) for detection of diseased coronary arteries in women with anginal pain, positive exercise stress test results, and angiographically normal coronary arteries (syndrome X). MATERIALS AND METHODS: Double-helical CT of the coronary arteries was performed in 81 consecutive women who were referred for coronary angiography for evaluation of chest pain. Patients were classified into three groups according to stress test and angiographic results: normal (normal exercise test results and angiographically normal coronary arteries), syndrome X (abnormal exercise test results and angiographically normal coronary arteries), and coronary artery disease (at least one diseased vessel seen at angiography). RESULTS: The prevalence of coronary calcification in the syndrome X group was 63% (10 of 16 patients) compared with 96% (45 of 47 patients) in the coronary artery disease group (P = .002) and 22% (four of 18 patients) in the normal group (P = .02). The lowest total coronary calcification score and logarithmic transformed data were found in the normal group (2.9 +/- 0.7), statistically significantly higher values were found in the syndrome X group (4.3 +/- 1.5), and the highest values were found in the coronary artery disease group (5.1 +/- 2.0; for trend, P = .03). CONCLUSION: Double-helical CT may be useful in detection of atherosclerosis in women with syndrome X who demonstrate normal coronary arteries at angiography.

Calcinosis↗
PubMed1996

[Ultrasound-guided aspiration of pleural fluid].

We review the outcome of guided, percutaneous, catheter drainage of pleural collections in 102 patients over a 2-year period. In 87% diagnostic aspiration of small or loculated collections was performed. Drainage of malignant and nonmalignant effusions in high-risk patients, or after failure of drainage without imaging guidance, was performed in 13%. All aspirations were successful and the only complication was a small pneumothorax in a single patient. If the collection was a small pneumothorax in a single patient. If the collections were large and easy to aspirate, we marked the best location for aspiration on the skin and sent the patient back to the ward for aspiration. We conclude that the use of sonography increases the proportion of successful drainage of small pleural collections and results in few complications.

Catheterization↗
PubMed1996

Takayasu arteritis in Israel--update.

Takayasu disease in our Israeli series consists of 56 patients, and has been detected only in Sephardic and oriental Jews as well as in Arabs and Bedouin. Suspicion of Takayasu disease should be raised whenever renal artery stenosis and involvement of the aorta and its branches occur in patients from oriental origin.

Adolescent↗
PubMed1996

Absence of coronary calcification on double-helical CT scans: predictor of angiographically normal coronary arteries in elderly women?

PURPOSE: To test the hypothesis that angiographically normal coronary arteries in elderly women are identifiable by the absence of coronary calcification on double-helical computed tomographic (CT) scans. MATERIALS AND METHODS: Forty-eight consecutive women (age range, 60-76 years) underwent coronary angiography for chest pain evaluation, as well as double-helical CT. Thirty women (mean age, 65 years +/- 5) had coronary artery disease (CAD), defined as any angiographic disease, and 18 women (mean age, 66 years +/- 4) had angiographically normal coronary arteries. RESULTS: Women with angiographically normal coronary arteries had lower coronary calcification scores than those of patients with CAD: 5.7 +/- 11 versus 580 +/- 634, respectively (P = .0004). Seven women with angiographically normal coronary arteries demonstrated mild coronary calcification (score < 50). Of the 11 women without coronary calcification, none had CAD. Thus, the absence of coronary calcification on double-helical CT scans in elderly women was predictive of angiographically normal coronary arteries with 61% sensitivity, 100% specificity, and 85% accuracy. CONCLUSION: Double-helical CT is an accurate, noninvasive modality for diagnosing angiographically normal coronary arteries in elderly symptomatic women.

Aged↗
PubMed1995

Ultrasonographic evaluation and clinical correlation of intratesticular lesions: a series of 39 cases.

OBJECTIVE: To assess the accuracy, specificity and sensitivity of ultrasonography (US) for diagnosing testicular tumours. PATIENTS AND METHODS: Ultrasonography of the scrotum was performed in 39 patients (mean age 20.3 years, range 3-61) referred to the hospital because of pain, tenderness, appearance of a mass in the scrotum or swelling of the scrotum after trauma. RESULTS: Intratesticular lesions were detected by US in 35 patients and four had no suspicious findings after surgical exploration of the scrotum based solely on clinical findings. In five patients the findings on US were compatible with neoplasm, but at surgery or follow-up, no tumour was found. In one case, the US findings suggested inflammation, but on exploration 3 weeks later, an embryonal cell carcinoma was found. CONCLUSIONS: While very sensitive in differentiating an intra-from an extratesticular lesion, and in ruling out a testicular tumour (sensitivity 96.6%), the US examination is less specific (specificity 44.4%) as the US pattern of different benign process may be similar to those of tumours. The positive predictive value (85.3%) and the accuracy (84.6%) imply that when an intratesticular lesion is detected on US, even when there is no clinical suspicion of neoplasm, exploration of the scrotum is indicated.

Adolescent↗
PubMed1995

Calcification of coronary arteries: detection and quantification with double-helix CT.

PURPOSE: To evaluate the accuracy of double-helix computed tomography (CT) in coronary artery calcification detection and quantification. MATERIALS AND METHODS: One hundred sixty patients with coronary disease (135 men, 25 women; age range, 45-62 years), of whom 138 had obstructive (stenosis of > 50% of diameter; n = 129) or mild (< 50% stenosis; n = 9) coronary artery disease (CAD) and 22 had normal coronary arteries (per angiographic findings), and 56 age-matched healthy control subjects underwent double-helix CT. RESULTS: Double-helix CT findings indicated that calcification was significantly more prevalent in patients with CAD (> 83%) than in patients with normal coronary arteries (27%) or in healthy control subjects (34%; P < .01). Sensitivity in detecting obstructive CAD was high (91%); however, specificity was low (52%) because of calcification in nonobstructive lesions. Comparison of double-helix CT and angiographic findings indicated that double-helix CT was 84% accurate with positive and negative predictive values of 89% and 59%, respectively. CONCLUSION: Double-helix CT is a useful noninvasive method for detection and quantification of coronary artery calcification.

Adult↗
PubMed1993

In vivo 31P NMR studies of paraplegics' muscles activated by functional electrical stimulation.

The bioenergetics of paralyzed muscles of spastic paraplegic patients under functional electrical stimulation (FES) was studied in vivo using 31P NMR. The protocol included rest, 3 min of induced tetanic isometric contraction through surface electrodes and 40 min of recovery. The continuous stimulation, the force recording and the 31P NMR measurements were sampled simultaneously inside the whole body imager. Normal values were found for the phosphorous metabolite ratios at rest. During contraction, prominent changes were detected including: a) accumulation of inorganic phosphate (Pi) accompanied by an unusually strong signal in the phosphomonoester (PME) region, b) phosphocreatine (PCr) decline, and c) a decrease in the intracellular pH. In the following recovery period the physiological state of the muscle was monitored and quantitated by 31P NMR. No metabolic and mechanical irreversible damage was detected in the paraplegics' muscles activated by FES under our experimental conditions.

Adult↗
PubMed1992

Acute severe combined demyelination.

We present a second case in which Guillain-Barré syndrome (GBS) and acute disseminated encephalomyelitis (ADEM) appeared simultaneously, both in acute and fulminant form. The patient, a 10-year-old girl, presented with acute onset of coma and flaccid, are-flexic quadriparesis. The elevated CSF protein levels and delayed F waves fulfilled the criteria of GBS and an MRI study revealed extensive multifocal demyelination compatible with a diagnosis of ADEM. Prompt clinical response followed by complete recovery was achieved by treatment with corticosteroids. It is suggested that acute severe combined demyelination might constitute a separate entity in which the demyelinating process, involving simultaneously the central and the peripheral nervous systems, indicates immune response against a component of the myelin of one system carrying cross-antigenicity with the other.

Acute Disease↗