Biomedical subjects

G Telman

Publications and source records attributed to G Telman.

5 recordsLinked to original sources

PubMed2006

Cerebral hemodynamics in symptomatic and asymptomatic patients with severe unilateral carotid stenosis before and after carotid endarterectomy.

BACKGROUND: Data concerning hemodynamic status prior to and after carotid endarterectomy (CEA) in symptomatic and asymptomatic patients is insufficient. Transcranial Doppler (TCD) provides information regarding compensatory collateral flow as well as mechanisms of cerebral autoregulation in patients with carotid stenosis. PATIENTS AND METHODS: Forty eight symptomatic and 81 asymptomatic patients with unilateral severe carotid stenosis were examined by TCD before and in early postoperative period after CEA. RESULTS: Cigarette smoking was the only risk factor significantly more frequent in symptomatic patients. Preoperative anterior cerebral artery (ACA) and middle cerebral artery (MCA) asymmetry, basilar artery velocity and number of ophthalmic arteries with reversed flow, were not significantly different between the two groups. Pulsatility index, cerebrovascular reactivity and flow acceleration on the side of stenosis were significantly lower in symptomatic patients. After surgery there was a significant improvement of all TCD parameters in symptomatic as well as asymptomatic patients. CONCLUSIONS: The exhausted ability of cerebral autoregulation is an important factor differentiating between symptomatic and asymptomatic patients with severe carotid stenosis. Successful surgery provides good recovery of cerebral hemodynamics in both symptomatic and asymptomatic patients.

Aged↗

PubMed2003

Assessment of ophthalmic artery collateral pathway in the hemispheric cerebral hemodynamics in patients with severe unilateral carotid stenosis.

The role of ophthalmic artery collateral pathway in hemispheric hemodynamics in patients with severe carotid stenosis is controversial. The aim of the present study was to address this question comparing the asymmetry of the velocity in middle and anterior cerebral arteries (MCAs and ACAs) and cerebrovascular reactivity (CVR) in MCA on stenotic side in the patients with unilateral severe stenosis of internal carotid artery (ICA) in patients with and without ophthalmic artery collateral pathway. The cohort of 118 patients with carotid stenosis was prospectively assembled. Fifty patients who had severe unilateral ICA stenosis (71%-99%) by Duplex Ultrasound (DUS) were observed by transcranial Doppler (TCD). Cerebral blood flow velocity in MCA and ACA in both sides, direction of blood flow in ophthalmic artery (OA) and CVR on the side of stenosis were determined. There were 14 patients with retrograde blood flow in OA (Group I). The remaining 36 patients with anterograde flow in OA composed Group II. The degree of interarterial asymmetry of peak and mean velocity (Vpeak and Vmean) in MCA and ACA and CVR in MCA were compared in both groups. The degree of ACA asymmetry by Vpeak was 44.0% +/- 6.9% in Group I and 38.3% +/- 3.9% in Group II (p = 0.49), by Vmean 40.3% +/- 6.7% and 36.6% +/- 3.8% (p = 0.63) respectively. The degree of MCA asymmetry by Vpeak was 24.2% +/- 2.8% in Group I and 19.5% +/- 5.0% in Group II (p = 0.42), by Vmean 23.5% +/- 2.9% and 20.6% +/- 5.1% (p = 0.63) respectively. CVR in Group I was 26.1% +/- 6.1%, in Group II 29.0% +/- 6.7% (p = 0.65). The ophthalmic collateral pathway has no influence on hemispheric cerebral hemodynamics in patients with severe unilateral carotid stenosis.

Aged↗

PubMed2002

The nature of microemboli in patients with artificial heart valves.

Cognitive decline has recently been found to be associated with microemboli in cerebral vessels in patients with artificial heart valves. The authors sought to determine the nature of such microemboli, that is, whether they are gaseous or solid, by comparing their characteristics to those of artificially generated air emboli in patients with patent foramen ovale (PFO). Three hundred and forty-eight microemboli were recorded in 11 patients with artificial valves (all taking coumadin), and 86 microemboli were recorded in response to intravenous injection of saline agitated with air in 8 PFO patients. No difference in intensity, duration, or relative velocity of microemboli was found between groups. The authors conclude that microemboli generated from artificial heart valves are generally gaseous and not solid.

Adult↗

PubMed1999

Monitoring of the extracranial and intracranial course of single emboli of cardiac origin: a preliminary report.

Simultaneous monitoring of emboli in extracranial and intracranial arteries recorded with identical probes, in a patient with an artificial cardiac valve, allowed the identification and characterization of pairs of signals, which most likely represent single emboli flowing through the common carotid artery into the middle cerebral artery. This technique offers new insight into emboligenesis with obvious therapeutic implications.

Carotid Artery Diseases↗

PubMed1996

[Post-shock optic neuropathy].

A case of rare, post-shock optic neuropathy is presented. In most cases, it occurs after blood loss or decrease in blood pressure. We present a woman, aged 47, with this condition in whom 3 possible causes, hypoxia, hypercoagulability and vasodilatation, coexisted. Neurologists and ophthalmologists should be aware of this rare condition, because prompt treatment with steroids and hemodynamic stabilization may significantly improve outcome.

Blood Coagulation Disorders↗