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Tony P Smith

Publications and source records attributed to Tony P Smith.

At least 19 recordsLinked to original sources
PubMed2006

Retrieval of the Günther Tulip and OptEase filters using the recovery cone removal system.

The Recovery Cone Removal System was evaluated in vitro to determine its feasibility as an alterative retrieval device for the Günther tulip and OptEase inferior vena cava filters. The cone removal system was then used electively in eight patients to determine feasibility and safety in vivo and subsequently in a single patient when wire-snare removal failed. The Recovery Cone Removal System allowed in vitro and in vivo retrieval in all cases without difficulty or complication. The Recovery Cone Removal System offers an alternative to the wire-snare-based retrieval systems for removal of the Günther tulip and OptEase filters.

Adult↗
PubMed2006

Radiation hand exposure during restoration of flow to the thrombosed dialysis access graft.

PURPOSE: To determine radiation dose to the hands of interventional radiologists during restoration of flow to thrombosed dialysis access grafts. MATERIALS AND METHODS: Sixty-two procedures were performed in 54 patients with thrombosed synthetic arteriovenous hemodialysis access grafts. For each procedure, five staff interventional radiologists wore thermoluminescent ring dosimeters on each hand. Overall hand doses were obtained, and patient and graft factors as well as technical factors were analyzed to determine the effects on hand exposure. RESULTS: The mean right hand and left hand exposures were 0.78 mSv and 0.55 mSv (78 and 55 mrem), respectively, and there was a significant difference between the two (P = .01). There was a significant difference among the interventionalists, mostly based on the lower doses associated with a single operator (P < .01). Not unexpectedly, fluoroscopy times (P < .01) and, to a lesser degree, the number of angiographic runs (P = .05) were significant factors influencing hand radiation dose. Patient sex, age and location of the graft, previous thrombosis, the number of previous interventions, and success or failure of the procedure were not significant factors in hand dose. CONCLUSIONS: Hand exposure during the restoration of flow to thrombosed dialysis access grafts is relatively high and is greater for the right hand than for the left. The exposures are dependent on technical factors, most notably fluoroscopy times, not on patient- or graft-related factors.

Adult↗
PubMed2006

Embolization in the external carotid artery.

The technical skill set of peripheral interventional radiologists is well-suited to the performance of most transcatheter embolization procedures in the external carotid artery (ECA). These procedures center in large part on hypervascular tumors, epistaxis, and trauma. ECA embolization in the trauma patient is well-defined, albeit in small patient series. The transcatheter treatment of epistaxis is still mostly reserved for cases that are intractable to conservative therapy. Preoperative embolotherapy for vascular tumors remains popular, although it is somewhat controversial in terms of its risk-benefit ratio. The purpose of this review is to highlight pertinent anatomy, selected technical procedural aspects, and the available literature to better characterize the role of ECA embolization in the hands of the practicing peripheral interventionist.

Carotid Artery, External↗
PubMed2005

Intra-arterial thrombolytic therapy in peri-coronary angiography ischemic stroke.

BACKGROUND: Intra-arterial thrombolysis (IAT) for peri-coronary angiography (CA) stroke may be safe and efficacious. However, IAT may increase the risk of intracranial hemorrhage (ICH). METHODS: A retrospective study was performed involving 3 university hospitals. All peri-CA IAT-treated cases were identified. Patient demographics, stroke severity, angiographic findings, thrombolytic use, modified Rankin Scale (mRS), ICH, and mortality were determined. RESULTS: A total of 21 patients with post-left CA stroke were treated with IAT (mean age 71.8+/-12.3 years). Arterial occlusion was found in 14 (66.7%) and 7 (33.3%) of the anterior and posterior circulation, respectively. Mean time-to-therapy was 36+/-12 minutes from the time the neurological deficit was noted. mRS < or =2 occurred in 10 of 21 (48%) patients. Patients with younger age and shorter time-to-IAT had more complete arterial recanalization and clinical recovery. Symptomatic ICH occurred in 3 (14%) cases, and 4 (19%) patients died. CONCLUSIONS: Peri-CA IAT appears to be feasible and safe without increased risk of symptomatic ICH and death when compared with the previously reported IAT literature.

Aged↗
PubMed2005

Angiographic diagnosis and endovascular management of nonvariceal gastrointestinal hemorrhage.

Diagnostic angiography still plays an essential role in the diagnosis of patients,particularly those with acute lower GI bleeding. Transcatheter therapy appears to be a viable treatment alternative in selected patients with GI bleeding. Many interventionists today believe embolotherapy to be more effective initially and to have better long-term results, specifically less rebleeding, than vasopressin infusion with at least equal complication rates. Unfortunately, direct comparison of the two techniques in a randomized, controlled fashion has not been performed. Small patient series, such as those summarized here, suggest that the results of the two techniques are essentially equal, and ischemic complications appear more prevalent with embolotherapy. The use of embolotherapy--either empirically based on endoscopic or surgical findings or directed against a site found to have contrast extravasation-represents the current intervention of choice in the case of upper GI bleeding refractory to endoscopic intervention. Head-to-head studies directly comparing the efficacy, morbidity, and mortality associated with endovascular or surgical correction of bleeding from the upper GI tract is needed. Although the current tide favors embolotherapy in the lower GI tract, infusion of vasoconstricting agents deserves more attention. To that end, there is a great need for scientific data regarding the safety and efficacy of transcatheter therapy for upper and lower GI bleeding.

Angiography↗
PubMed2005

Thrombolytic therapy of acute ischemic stroke: correlation of angiographic recanalization with clinical outcome.

BACKGROUND AND PURPOSE: The effect of vessel patency, following recombinant tissue plasminogen activator (rtPA) administration, on clinical outcome in acute ischemic stroke (AIS) has been controversial. We studied the effect of recanalization following intraarterial (IA) and intravenous/IA (IV/IA) rtPA on clinical outcome in AIS. METHODS: Recanalization was classified angiographically as complete (as compared with unoccluded vessel, thrombolysis in myocardial infarction classification [TIMI] 3), none (with no change from prethrombolysis, TIMI 0), and partial (when a change in the flow from baseline was noted, TIMI 1-2). Outcomes were symptomatic intracranial hemorrhage (sICH), 90-day modified Rankin scale (< or = 2 as a good outcome), and 3-month mortality. RESULTS: Ninety-six patients had either combined IV/IA (41) or IA (55) rtPA for AIS during a 7-year period. Any recanalization occurred in 69%; 55% of those had a good outcome versus 23% in the rest (Odds ratio = 3.9; 95% confidence interval [CI] = 1.4-11.2; P = .007). Only 24% had complete recanalization; 74% had a good outcome versus 36% in the nonrecanalization group (OR = 5.1; 95% CI = 1.6-16.8; P = .002). When adjusted to time to therapy and vessel occluded, these results lessened but remained significant. The sICH rate with any recanalization was 7.6% versus 13.3% in patients with persistent clot (relative risk (RR) = 0.6; 95% CI = 0.2-2.0; P = .45). Death occurred in 19.7% of those whose vessels recanalized versus 33.3% in the rest (RR = 0.56; 95% = 0.26-1.19; P = .2). CONCLUSION: A total of 24% and 69% of patients had complete and any recanalization, respectively, following endovascular rtPA therapy of AIS. The degree of recanalization was directly related to time to therapy and associated with good clinical outcome without an increase in the rate of adverse effect.

Aged↗
PubMed2004

Transhepatic catheter access for hemodialysis.

PURPOSE: To retrospectively review the authors' experience regarding the safety and functionality of transhepatic hemodialysis catheters. MATERIALS AND METHODS: Sixteen patients (seven men and nine women aged 21-77 years; mean age, 51.6 years) underwent placement of 21 transhepatic hemodialysis catheters. Transhepatic catheters were placed in the absence of an available peripheral venous site (11 patients) or for preservation of a single remaining venous site to achieve permanent vascular access. Safety was assessed by means of complications encountered, and catheter functionality was assessed by means of total access site service interval. Catheter patency was described by using a Kaplan-Meier survival curve, and number of catheter days were compared according to patient sex by using a two-sample t test. RESULTS: Technical success was achieved in all patients. The mean total access site service interval was 138 catheter days (range, 0-599 days), and there was no significant difference according to patient sex (P =.869). Of the 16 catheters placed initially, five became dislodged and required an additional access procedure to be performed. These 21 catheters required 30 exchanges in 10 patients (48%) (range, 1-6 exchanges per patient). The most common reason for catheter exchange was device failure. There were six complications among 21 catheters placed (29%), including one death from massive intraperitoneal hemorrhage on the day after catheter placement. CONCLUSION: Transhepatic hemodialysis catheters offer a viable option to patients with limited options; however, there are maintenance issues and complications.

Adult↗
PubMed2004

Sepsis in the interventional radiology patient.

Interventional radiologists often treat patients who are at risk of becoming acutely septic while in the radiology department. Identifying those most at risk and initiating treatment plans before the acute situation are fundamental to this difficult group of patients. Treatment plans for life-threatening infection are based on controlling the source of infection and administering appropriate systemic antimicrobial therapy as well as volume and cardiopulmonary support. The purpose of this review is to provide a framework for the diagnosis and treatment of sepsis in the interventional radiology patient.

Humans↗
PubMed2004

Antibiotic prophylaxis in interventional radiology.

Despite several decades of advances in both minimally invasive techniques and antibiotic therapy, infection remains one of the more common complications of invasive procedures. Interventional radiology (IR) has traditionally been believed to be associated with lower infection rates than surgery. However, new interventional techniques, as well as more aggressive therapeutic interventions, have presented new challenges in relation to pharmacological management of postprocedural infection and pain. The risk of infection associated with IR procedures can never be completely eliminated, and the reasons for this are manifold, including more virulent organisms, ongoing and newly emerging antibiotic resistance, increased numbers of immunocompromised patients, and the adoption into everyday interventional practice of more aggressive interventional techniques such as chemoembolization, uterine fibroid embolization, and complex biliary intervention. Despite the widespread use of prophylactic antibiotics in IR, and the widely held belief that they are beneficial and are the standard of care, randomized controlled clinical trials have never validated the use of antibiotics in this setting. As such, an argument could be made not to use antibiotics at all for prophylaxis in IR. The purpose of this article is to discuss some of the issues relating to the use of prophylactic antibiotics, and what choice of antibiotics physicians make when they decide to use prophylaxis for IR procedures.

Antibiotic Prophylaxis↗
PubMed2004

Early carotid artery stenting and angioplasty in patients with acute ischemic stroke.

OBJECTIVE: To determine the safety of early percutaneous endovascular carotid angioplasty and stenting (CAS) after an ischemic stroke. METHODS: The neurointerventional database was reviewed for patients who underwent CAS after an acute ischemic stroke in two university hospitals. Clinical and radiological data were reviewed. Outcomes were worsening stroke, new stroke, or stroke-related death up to 30 days after the procedure. Procedure-related complications were also documented. RESULTS: A total of 38 patients with 39 procedures were identified. The mean age was 67 +/- 15 years; 31 of 38 patients were Caucasian and 24 were female. Hypertension was found in 21 patients, peripheral vascular disease in 12, diabetes in 13, and coronary artery disease in 18. The median initial National Institutes of Health Stroke Scale score was 8. The carotid artery showed severe to high-grade stenosis in 28 patients, dissection was present in 6, and the rest had an acute occlusion treated with thrombolysis followed by CAS. The mean time from stroke onset to CAS was 55 +/- 34 hours. The mean degree of stenosis at baseline was 86 +/- 11%. In 37 procedures, complete recanalization was achieved, defined as less than 10% residual narrowing; in 2 procedures, the residual stenosis was mild (10-20%). Neurological deterioration occurred after three procedures (7.7%), with minor nondisabling stroke in two and death from intracranial hemorrhage in one. CONCLUSION: If deemed necessary and in certain circumstances, early CAS seems to be safe after acute ischemic stroke if infarction volume is small and neurological deficit is mild.

Aged↗
PubMed2003

Transjugular biopsy of the liver in pediatric and adult patients using an 18-gauge automated core biopsy needle: a retrospective review of 410 consecutive procedures.

OBJECTIVE: The aim of our study was to evaluate the safety and efficacy of transjugular biopsy of the liver in a large population of patients using an 18-gauge automated core biopsy needle. MATERIALS AND METHODS: A total of 371 patients underwent 410 attempted transjugular biopsies of the liver during an 80-month period. Data collected included the retrospective review of patients' computerized medical records, clinical charts, and nursing documents. Patient demographic data, indications for liver biopsy, laboratory findings of coagulation values, procedural data including number of needle passes performed, and histologic description of the specimens were noted. Indications varied and included traditional contraindications to the percutaneous approach such as coagulopathy (53%) and ascites (29%). In one patient, the hepatic veins could not be catheterized because of angulation with the inferior vena cava, and in one patient, biopsy was performed using the femoral route because of occlusion of the jugular vein. All patients were followed up for a minimum of 24 hr after the procedure to determine complications. RESULTS: The mean number of needle passes per procedure was 3.4 (range, 0-18). Hepatic tissue was obtained in 409 procedures via the venous route (408 transjugular and one transfemoral), and a tissue diagnosis was achieved in 403 (98%). The six tissue samples were nondiagnostic because they were too small (n = 3) or too fragmented (n = 1) or because they did not contain hepatic tissue (n = 2). Ten complications (2.4%) occurred, including three intraperitoneal hemorrhages that resulted in one death. CONCLUSION: Transjugular biopsy of the liver using an automatic core biopsy needle is safe and produces adequate tissue specimens in a high percentage of patients.

Adolescent↗
PubMed2003

Delayed stenosis following placement of a polyethylene terephthalate endograft in the cervical carotid artery. Report of three cases.

Three patients with carotid artery (CA) pseudoaneurysms were treated using four polyethylene terephthalate endografts (Wallgraft endoprostheses). Two patients received a single graft and one patient with bilateral pseudoaneurysms received two grafts. Complete occlusion of the pseudoaneurysm with patency of the arterial lumen was achieved following endograft placement in all patients. The clinical follow-up interval ranged from 12 to 18 months and included angiography or ultrasonography studies or both. One patient experienced neurological symptoms, and in-graft stenosis ranging from 50 to 100% occurred in three of the four grafts. Although the Wallgraft endoprosthesis produced good initial results for the treatment of cervical CA pseudoaneurysms, as demonstrated on radiography, it was associated with a high rate of stenosis or occlusion in all three patients.

Adult↗
PubMed2002

Treatment of an iatrogenic petrous carotid artery pseudoaneurysm with a Symbiot covered stent: technical case report.

OBJECTIVE AND IMPORTANCE: Surgery involving the middle ear or the temporal bone may cause an injury to the petrous carotid artery resulting in a pseudoaneurysm. Conventional treatment of such pseudoaneurysms has ranged from carotid occlusion to conservative management. The use of a balloon-expandable stent and/or Guglielmi detachable coils may be effective in a partially healed pseudoaneurysm. This report details the case of an acute petrous carotid pseudoaneurysm after a myringotomy procedure that was effectively treated with an expanded polytetrafluoroethylene-covered stent. CLINICAL PRESENTATION: During a right myringotomy procedure, pulsatile blood was encountered in a 42-year-old woman with a history of repeated ear infections and bilateral middle ear ventilation tube placement. The blood was adequately tamponaded with gauze packing. Computed tomography of the temporal bone demonstrated a dehiscent carotid artery, and cerebral angiography revealed a 6-mm right petrous carotid pseudoaneurysm. INTERVENTION/TECHNIQUE: An 8-French guide catheter was positioned via a transfemoral approach into the cervical right internal carotid artery, and the patient was systemically heparinized. A 4- x 31-mm Symbiot covered stent (Boston Scientific/Scimed, Maple Grove, MN) was passed over a Choice PT exchange wire (Boston Scientific/Scimed) to cover the neck of the pseudoaneurysm, obliterating the pseudoaneurysm. The patient was given aspirin and clopidogrel after stenting, and ear exploration was possible later the same day. Follow-up computed tomographic angiography performed 6 weeks later verified patency of the stent. CONCLUSION: The use of an expanded polytetrafluoroethylene-covered stent may effectively treat intracranial internal carotid artery pseudoaneurysms in an acute setting. This treatment allows preservation of the parent artery and immediate treatment by reconstruction of the incompetent arterial wall to prevent potentially life-threatening hemorrhagic complications.

Adult↗