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T S Riles

Publications and source records attributed to T S Riles.

95 records · Page 6Linked to original sources
PubMedDate not supplied

The carotid bifurcation plaque: pathologic findings associated with cerebral ischemia.

Embolization from or decreased flow through cervical carotid and vertebral arteries causes ischemic stroke syndromes. Specific pathologic findings were studied in 50 symptomatic patients who underwent 69 carotid endarterectomies. Detailed analyses of their carotid plaques included correlations between photographs of gross specimens, microscopic findings, angiograms, preoperative symptoms and long-term postoperative follow up. Carotid plaques were primarily fibrous with significant (greater than 70%) stenoses encountered in 70% of the arteries. Stenoses were due to simple fibrous thickening in only 20%; the remainder due to intraplaque hemorrhage, atheromatous debris and, least often, luminal thrombus with or without ulceration. Intramural hemorrhage was frequent in plaques associated with focal neurologic symptoms and may have preceded localized collections of atheromatous debris. Ulceration occurred in 1/3 of all plaques, symptomatic or not. It is concluded that the carotid plaques start as fibrointimal thickening evolving to symptomatic stages by the occurrence of one or more of a number of pathologic changes, intraplaque hemorrhage being prominent. A single rational therapeutic regimen seems impossible until patients can be classified according to their pathologic changes diagnosed non-invasively.

Arteriosclerosis↗
PubMedDate not supplied

Successful limb reperfusion using prolonged intravascular shunting in a case of an unstable trauma patient--a case report.

When peripheral vascular injuries present in conjunction with life threatening emergencies, controlling hemorrhage from a peripheral blood vessel may take initial priority, however, sacrificing a limb to preserve life is a well-established dictum. The use of intravascular shunts has allowed arterial and venous injuries to be controlled and temporized while treating other injuries. Typically, intravascular shunts are used for short time periods while orthopedic injuries are repaired or other life threatening injuries are managed. The following case demonstrates the long-term use of an intravascular arterial shunt to treat a traumatic transection of the common femoral artery and vein in a patient with an open pelvic fracture from blunt trauma. A 20-year-old woman fell between a subway platform and an oncoming train. She sustained a crush injury to her lower extremity and pelvis as she was pinned between the train and platform. The patient presented with active hemorrhage from a groin laceration, quickly became hemodynamically unstable, and was brought to the operating room. In addition to a pelvic fracture with massive pelvic hematoma she sustained a complete transection of the bifurcation of the common femoral artery (CFA), the common femoral vein (CFV), and associated orthopedic injuries. Vascular shunts were placed in the common femoral artery and vein. The patient became hypotensive from an expanding retroperitoneal hematoma. Pelvic bleeding was controlled with angioembolization and the venous injury was repaired. At this time the patient became cold, acidotic, and coagulopathic. It was thought unsafe to proceed with the arterial repair and it was elected to keep her arterial shunts in place and perform a planned reexploration in 24 hours after correcting her physiologic status. The patient returned to the operating room for an elective repair of her CFA the following day. Her shunt had remained patent throughout this time. She underwent a reverse saphenous vein graft from her CFA to her SFA. After a prolonged hospital course she was ultimately transferred to a rehabilitation center with intact pulses in both lower extremities. This case demonstrates the effectiveness of prolonged (>6 hours) use of an intravascular shunt as part of damage control surgery for peripheral arterial and venous injuries. In a patient who would otherwise undergo an amputation for their injury, the risk of shunt thrombosis, or infection, during damage control resuscitation may not be a contraindication for placement.

Adult↗
PubMedDate not supplied

Diagnosis of carotid artery stenosis: comparison of 2DFT time-of-flight MR angiography with contrast angiography in 50 patients.

Fifty patients underwent 2DFT time-of-flight MR angiography and intraarterial contrast angiography for evaluation of possible carotid atherosclerotic disease. The MR angiography technique employed contiguous axial flow-sensitive (short TR/TE) slices that were reformatted and postprocessed by using a maximum-intensity projection algorithm to provide 16 angiographic views of the carotid arteries. Both studies were independently reviewed by two observers in a blinded manner. Carotid arteries were categorized as normal, mildly stenotic, moderately stenotic, severely stenotic, or occluded. For the 94 carotid arteries available for review, one observer reported a 70% agreement between the two techniques and the second observer reported a 56% agreement (p = .0001). The best correlation was in the severely stenotic category and the worst was in the occluded category. Agreement between observers was 67% for MR angiography and 72% for contrast angiography, which was similar to that between the two techniques. Although not all carotid atherosclerotic disease was visualized equally well, 2DFT time-of-flight MR angiography had a good overall correlation with the "gold standard" of intraarterial contrast angiography, supporting its use as a screening technique. While further improvements are needed, use of MR angiography as the primary diagnostic tool for many patients with suspected carotid stenosis should continue to increase.

Aged↗
PubMedDate not supplied

Early complications of carotid surgery.

The early complications of carotid endarterectomy are attributed to clamping ischemia, intraoperative embolization, and thrombosis of the newly endarterectomized carotid artery. An unusual mechanism is due to intracranial hemorrhage. The differential diagnosis can usually be established by a combination of oculoplethysmography, CT scanning of the brain, exploration of thrombosed carotid arteries, and repeat angiographic studies. Other complications, including acute myocardial infarction, wound hemorrhage, and infection, are discussed.

Brain Diseases↗