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Walter Kucharczyk

Publications and source records attributed to Walter Kucharczyk.

5 recordsLinked to original sources

Interstitial Doppler optical coherence tomography.

Doppler optical coherence tomography (OCT) can image tissue structure and blood flow at micrometer-scale resolution but has limited imaging depth. We report a novel, linear-scanning, needle-based Doppler OCT system using angle-polished gradient-index or ball-lensed fibers. A prototype system with a 19-guage (diameter of approximately 0.9 mm) echogenic needle is constructed and demonstrates in vivo imaging of bidirectional blood flow in rat leg and abdominal cavity. To our knowledge, this is the first demonstration of Doppler OCT through a needle probe in interstitial applications to visualize deeply situated microcirculation.

Animals↗

Tranexamic acid and early saphenous vein graft patency in conventional coronary artery bypass graft surgery: a prospective randomized controlled clinical trial.

OBJECTIVE: Use of antifibrinolytic agents reduces the risk of bleeding and decreases the need for blood product use in patients undergoing cardiac surgery. The purpose of this study was to determine whether perioperative use of tranexamic acid decreases the rate of saphenous vein graft patency in the early postoperative period after conventional coronary artery bypass grafting surgery. METHODS: A total of 312 patients scheduled for elective coronary artery bypass grafting surgery with cardiopulmonary bypass were randomized to receive either tranexamic acid 100 mg/kg (n = 147) or placebo (n = 165) in a double-blinded fashion before the initiation of cardiopulmonary bypass. Saphenous vein graft patency was assessed with magnetic resonance imaging 5 to 30 days after surgery. RESULTS: Both groups were comparable with respect to baseline demographic data and surgical characteristics. A total of 237 (76%) patients underwent magnetic resonance imaging assessment. A total of 297 saphenous vein grafts were performed and 253 (85.2%; 95% confidence interval, 83.5%-86.9%) were seen in the tranexamic acid group, and 265 saphenous vein grafts were performed and 231 (87.2%; 95% confidence interval, 85.5%-88.9%) were seen in the placebo group (P = .4969). The blood loss and blood product transfusion rates in the tranexamic acid group were significantly lower than in the placebo group. There was no difference between groups with respect to postoperative morbidity and mortality. CONCLUSIONS: The administration of tranexamic acid before cardiopulmonary bypass did not seem to compromise early venous graft patency rates but reduced perioperative blood product transfusion rates. Consequently, tranexamic acid could be advocated for routine use in patients undergoing conventional coronary artery bypass grafting surgery.

Aged↗

Neuroradiologic screening in normal-pressure glaucoma: study results and literature review.

PURPOSE: To determine if there was an increased prevalence of intracranial compressive lesions in patients with clinically diagnosed normal-pressure glaucoma compared with a group of patients with progressive primary open-angle glaucoma. PATIENTS AND METHODS: In a prospective, comparative, observational case series, the authors performed cranial magnetic resonance imaging in patients with consecutively diagnosed normal-pressure glaucoma (n = 62) and progressive primary open-angle glaucoma with controlled intraocular pressures (n = 70). The prevalence of intracranial compressive lesions, demographic data, and clinical characteristics were compared between both groups. RESULTS: Four of the 62 (6.5%) patients with normal-pressure glaucoma had clinically relevant intracranial compressive lesions involving the anterior visual pathway, compared with none of the 70 patients with primary open-angle glaucoma (P = 0.039). CONCLUSIONS: Intracranial compressive lesions are an important diagnostic consideration in the workup of normal-pressure glaucoma.

Adenoma↗