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Z Jamil

Publications and source records attributed to Z Jamil.

At least 19 recordsLinked to original sources
PubMed2001

In-stent restenosis after carotid angioplasty-stenting: incidence and management.

PURPOSE: Carotid angioplasty-stenting (CAS) has been advocated as an alternative to carotid endarterectomy (CEA) in patients with restenotic lesions after prior CEA, primary stenoses with significant medical comorbidities, and radiation-induced stenoses. The incidence of restenosis after CAS and its management remains ill defined. We evaluated the incidence and management of in-stent restenosis after CAS. METHODS: Patients with asymptomatic (61%) and symptomatic (39%) carotid stenosis of > or = 80% underwent CAS between September 1996 and May 2000; there were 50 procedures and 46 patients (26 men and 20 women). All patients were followed up clinically and underwent duplex ultrasonography (DU) at 3- to 6-month intervals. In-stent restenoses > or = 80% detected with DU were further evaluated by means of angiography for confirmation of the severity of stenosis. RESULTS: No periprocedural or late strokes occurred in the 50 CAS procedures during the 30-day follow-up period. One death (2.2%) that resulted from myocardial infarction was observed 10 days after discharge following CAS. During a mean follow-up period of 18 +/- 10 months (range, 1-44 months), in-stent restenosis was observed after four (8%) of the 50 CAS procedures. Angiography confirmed these high-grade (> or = 80%) in-stent restenoses, which were successfully treated with balloon angioplasty (3) or angioplasty and restenting (1). No periprocedural complications occurred, and these patients remained asymptomatic and without recurrent restenosis over a mean follow-up time of 10 +/- 6 months. CONCLUSIONS: We recommend CAS for post-CEA restenosis, primary stenoses in patients with high-risk medical comorbidities, and radiation-induced stenoses. In-stent restenoses occurred after 8% of CAS procedures and were managed without complications with repeat angioplasty or repeat angioplasty and restenting.

Aged↗
PubMed1999

Patency and limb salvage for polytetrafluoroethylene bypasses with vein interposition cuffs.

Polytetrafluoroethelene (PTFE) is often utilized in patients with limb-threatening ischemia requiring infrainguinal revascularization in the absence of autologous saphenous vein. To increase long-term patency of PTFE grafts, vein interposition cuffs have been recommended as adjunctive procedures. The purpose of this study was to assess the efficacy of vein interposition cuffs on the long-term patency and limb salvage of patients requiring prosthetic bypass grafts for limb-threatening ischemia. Prosthetic bypass grafts with vein interposition cuffs (PTFE/VC) were performed on 56 limbs in 55 patients (32 men, 23 women; mean age of 67 years) from October 1993 to January 1998. Grafts were prospectively evaluated every 3 months for the first 12 months and biannually thereafter with duplex ultrasonography. PTFE/VC and PTFE bypasses at the popliteal level appear to have comparable patencies. However, PTFE/VC appear to offer an improved patency and limb salvage for infrapopliteal bypasses in patients with critical limb ischemia. When infrapopliteal revascularization is required in the absence of autologous saphenous vein, we recommend the use of PTFE with vein interposition cuffs.

Aged↗
PubMed1999

Mandibular subluxation for distal internal carotid exposure: technical considerations.

PURPOSE: Carotid endarterectomy (CEA) has become one of the most commonly performed vascular procedures, because of the beneficial outcome it has when compared with medical therapy alone and because of the anatomic accessibility of the artery. In cases of distal carotid occlusive disease, high cervical carotid bifurcation, and some reoperative cases, access to the distal internal carotid artery may limit surgical exposure and increase the incidence of cranial nerve palsies. Mandibular subluxation (MS) is recommended to provide additional space in a critically small operative field. We report our experience to determine and illustrate a preferred method of MS. METHODS: Techniques for MS were selected based on the presence or absence of adequate dental stability and periodontal disease. All patients received general anesthesia with nasotracheal intubation before subluxation. Illustrations are provided to emphasize technical considerations in performing MS in 10 patients (nine men and one woman) who required MS as an adjunct to CEA (less than 1% of primary CEAs). Patients were symptomatic (n = 7) or asymptomatic (n = 3) and had high-grade stenoses demonstrated by means of preoperative arteriography. RESULTS: Subluxation was performed and stabilization was maintained by means of: Ivy loop/circumdental wiring of mandibular and maxillary bicuspids/cuspids (n = 7); Steinmann pins with wiring (n = 1); mandibular/maxillary arch bar wiring (n = 1); and superior circumdental to circummandibular wires (n = 1). MS was not associated with mandibular dislocation in any patient. No postoperative cranial nerve palsies were observed. Three patients experienced transient temporomandibular joint discomfort, which improved spontaneously within 2 weeks. CONCLUSION: Surgical exposure of the distal internal carotid artery is enhanced with MS and nasotracheal intubation. We recommend Ivy loop/circumdental wiring as the preferred method for MS. Alternative methods are used when poor dental health is observed.

Adult↗
PubMed1999

Hemodialysis access: influence of the human immunodeficiency virus on patency and infection rates.

PURPOSE: The complication rate for patients who are dialysis dependent and infected with the human immunodeficiency virus (HIV) and the role of viral indicators (CD4 counts) as predictors of these complications are poorly characterized. To determine the influence of HIV status and viral activity on graft patency and infection rates, we retrospectively reviewed our results. METHODS: Between June 1993 and March 1997, the charts of 104 patients (HIV+, n = 42; HIV-, n = 62) who required 112 hemodialysis access grafts were reviewed. Of the 112 procedures, 55 (48%) were autologous arteriovenous fistulae (AVF) procedures (HIV+, n = 23; HIV-, n = 32) and 57 (52%) were prosthetic expanded polytetrafluoroethylene grafting procedures (HIV+, n = 27; HIV-, n = 30). Transcutaneous catheter procedures were excluded from the study. The autologous AVF procedures consisted of direct and transposed AVFs. Patency rates were determined by means of life-table analysis. Infection rates and CD4 counts were compared with the chi2 test and the Fisher exact test. Significance was accepted at a P value of.05 or less. RESULTS: The cumulative 12-month and 24-month patency rates for prosthetic grafts in patients who were HIV+ were 49% and 21%, respectively, versus 77% and 45% for patients who were HIV-. The differences in the prosthetic graft patency rates between these two groups were significant (P </=.05). The cumulative 12-month and 24-month patency rates for autologous AVF procedures did not differ significantly. The AVF procedure patency rates were 72% and 51%, respectively, in patients who were HIV+ versus 54% and 50% for patients who were HIV-. The prosthetic graft infection rate for patients who were HIV+ and HIV- were 30% and 7%, respectively ( P =.04). However, the infection rates in autologous AVF procedures did not differ between the groups (9% vs 0%; P>.05). The mean CD4+ cell counts were 174: CD4+ counts that were less than 200 did not correlate with or predict the development of infection (P >.05). CONCLUSION: Our data showed that prosthetic graft infection rates were increased and patency rates were decreased in patients who were HIV+ as compared with patients who were HIV- and HIV+ with autologous AVFs. There were no differences in patency rates or infection rates in patients who had undergone autologous access procedures. Long-term graft patency rates were not affected by HIV status, and CD4+ lymphocyte counts were not predictive of infection development. Because the prosthetic graft infection rates exceeded those rates of autologous access procedures, we recommend the vigorous use of autologous AVFs in all patients who are HIV+, regardless of CD4+ count.

Blood Vessel Prosthesis Implantation↗
PubMed1999

Carotid restenosis: operative and endovascular management.

PURPOSE: Surgical management of carotid restenosis (CR) after carotid endarterectomy (CEA) has been associated with a higher perioperative complication rate than that of primary CEA. We recently used carotid angioplasty-stenting (CAS) as an alternative to operative management in patients who had undergone CEA within three years, and we retrospectively compared these results with those of operative management of CR and the overall results of CEA. METHODS: CEA was performed on 1065 adult patients (58% symptomatic, 42% asymptomatic), 62% of whom were men (n = 660) and 38% of whom were women (n = 405), from 1989 to 1997. Before our initiation of a program of CAS, 16 operative procedures (1.9% of CEAs) were performed for CR in 14 adult patients (7 women and 7 men). During the last 20 months, CAS was used in the management of 17 CRs (16 patients; 9 women and 7 men). RESULTS: The 30-day stroke morbidity-death rate for all CEAs (n = 1065) was 1.4%; 11 strokes (1. 0%) occurred (4 major strokes with disability and 7 strokes with minor or no disability), and 4 deaths (0.4%) occurred (2 deaths caused by myocardial infarction, 1 caused by intracranial hemorrhage, and 1 caused by stroke). Operative management of CR (n = 16) included patch angioplasty in 12 cases (autologous vein patches in 10 cases and synthetic patches in 2 cases), whereas interposition grafting was used in 4 cases (saphenous vein in 3 instances and synthetic [polytetrafluoroethylene] in one case). No strokes or deaths were observed. One recurrent laryngeal nerve palsy occurred (6.2%). Among the 16 patients undergoing 17 CAS procedures, the technical procedures were accomplished in all patients. No strokes or deaths occurred. No recurrent restenoses (50% or greater) have been identified within or adjacent to the CAS procedures. CONCLUSION: CR caused by myointimal hyperplasia can be managed by operative techniques or CAS with comparable periprocedural complications. Although long-term follow-up will be required to determine the incidence of recurrent restenosis, CAS may become the preferred procedure in these cases. A randomized clinical trial ultimately will be necessary to determine the role of CAS, as compared with that of operative management.

Aged↗
PubMed1998

A strategy for increasing use of autogenous hemodialysis access procedures: impact of preoperative noninvasive evaluation.

PURPOSE: We studied the efficacy of preoperative noninvasive assessment of the upper extremity to identify arteries and veins suitable for hemodialysis access to increase our use of autogenous fistulas (AF). METHODS: From Sep. 1, 1994, to Apr. 1, 1997, 172 patients who required chronic hemodialysis underwent segmental upper extremity Doppler pressures and duplex ultrasound with mapping of arteries and veins. The following criteria were necessary for satisfactory arterial inflow: absence of a pressure gradient between arms, patent palmar arch, and arterial lumen diameter 2.0 mm or more. The criteria necessary for satisfactory venous outflow were venous luminal diameter greater than or equal to 2.5 mm for AF and greater than or equal to 4.0 mm for synthetic bridging grafts (BG) and continuity with distal superficial veins in the arm. Intraoperative and duplex ultrasound measurements were compared. Contemporary experience was compared with the 2-year period (1992 to 1994) before implementation of the protocol. RESULTS: During the period from Sep. 1, 1994, to Apr. 1, 1997, 108 patients (63%) had AF, 52 (30%) had prosthetic BG, and 12 (7%) had permanent catheters (PC) placed. Early failure was seen in 8.3% of AFs. Primary cumulative patency rates were 83% for AF and 74% for BG at 1 year (p < 0.05), with a mean clinical follow-up of 15.2 months. No postoperative infections were observed with AF, whereas six infections (12%) were observed with BG and two (17%) with PC insertion. During the period from June 1, 1992, to Aug. 31, 1994, 183 procedures were performed with a distribution of 14% AF, 62% BG, and 24% PC. In this earlier period the AF early failure rate was 36%, and the patency rates were 48%, 63%, and 48% for AF, BG, and PC, respectively (mean follow-up, 13.8 months). CONCLUSION: A protocol of noninvasive assessment increased use of AFs. The cumulative patency rate of AFs was improved, and early failure rates were reduced when compared with the preceding institutional experience. Routine noninvasive assessment is recommended to document adequacy of arterial inflow and delineate venous outflow to maximize opportunities for AF.

Arm↗
PubMed1998

Patency of infrainguinal polytetrafluoroethylene bypass grafts with distal interposition vein cuffs.

Polytetrafluoroethylene (PTFE) prosthetic bypasses in the lower extremity have poor patency rates, particularly in limb salvage cases. Patency and limb salvage rates of PTFE bypasses supplemented by distal interposition vein cuffs were assessed in patients requiring revascularization for critical limb ischemia, in the absence of a suitable autologous saphenous vein. Between October 1993 and April 1996, 163 patients underwent 185 infrainguinal bypasses. Forty-three limbs in 42 patients (12 women, 30 men; mean age 67 years) did not have a suitable autologous saphenous vein (24%) and had femoropopliteal (20) and infrapopliteal (23) bypasses performed. Patients were examined prospectively at 3-month intervals during the first year and at 6-month intervals thereafter to determine graft patency and limb salvage. Postoperative anticoagulation with warfarin was used in 26 patients. Indications for operation included limb salvage in 41 extremities (21 rest pain/ulceration or gangrene, 20 rest pain alone), and disabling claudication in two. Patients were followed clinically for 2-30 months (mean 10 months). Cumulative 2-year life-table patencies for all grafts, femoropopliteal and infrapopliteal bypasses were 64%, 75% and 62%, respectively. Previous primary patencies at the authors' institution for PTFE bypasses without vein cuffs were 35%, 46% and 12% for the same categories. Cumulative life-table limb salvage for all PTFE/vein cuff bypasses in the present series was 76% compared with 37% in previous PTFE bypasses without vein cuffs. Adjunctive use of distal interposition vein cuffs improves prosthetic graft patency, while producing satisfactory limb salvage. Postoperative anticoagulation did not influence graft patency. PTFE/vein cuff for lower-extremity revascularization shows good 2-year patency and is an acceptable alternate conduit in patients with critical limb ischemia when autologous saphenous vein is absent.

Aged↗
PubMed1997

Vein transposition in the forearm for autogenous hemodialysis access.

PURPOSE: We describe a technique of superficial venous transposition in the forearm used for the formation of an arteriovenous fistula for hemodialysis access. These modifications of the single-incision radiocephalic fistula are designed to increase options for arteriovenous fistulas by using veins and arteries that are suitable for use but are not in immediate proximity. METHODS: Arteries and veins suitable for a primary arteriovenous fistula were identified and mapped using duplex ultrasound in 89 patients. Separate incisions were used in the majority of cases, and the selected forearm vein was mobilized, angiodilated, and transposed into a subcutaneous tunnel on the volar aspect of the forearm. Before initiation of hemodialysis, duplex ultrasound scanning was performed, and the location that was most suitable for cannulation was identified. Repeat scans were performed at 3-month intervals for analysis of patency. RESULTS: Superficial venous transpositions were performed using a single incision in 13 instances in which the vein was in immediate proximity to the radial artery (type A). Dorsal-to-volar forearm transposition (type B) was performed in 30 veins with anastomoses to the radial (n = 26), ulnar (n = 2), or brachial (n = 2) arteries. Volar-to-volar forearm transposition (type C) was performed in the remaining 46 veins, with anastomoses to the radial (n = 42), ulnar (n = 2), or brachial arteries (n = 2). Successful hemodialysis was accomplished in 81 of 89 patients (91%). The primary cumulative patency rate was 84% at 1 year and 69% at 2 years. The mean duration of follow-up was 14.3 months. CONCLUSIONS: The use of superficial venous transposition for the formation of autogenous hemoaccess was associated with ease of cannulation by dialysis personnel, high maturation rates, reduced early failure rates, and enhanced patency rates. We recommended the use of these technical modifications to increase the use of autogenous fistulas in the forearm.

Adult↗
PubMed1997

Outcome of complex venous reconstructions in patients with trauma.

PURPOSE: The role of complex venous reconstructions (CVRs) in patients with major trauma remains a controversial topic. This study evaluates the patency and clinical outcome of CVRs in a major urban trauma center. METHODS: Between 1979 and 1994 the records of 92 patients with 100 injuries to the iliac, femoral, and popliteal venous system were reviewed. The incidence of edema, pulmonary embolism, and limb loss was documented in 75 men and 17 women (mean age of 27 years, range 14 to 59 years). The 30-day patencies were assessed in all patients with either impedance plethysmography (n = 16), venography (n = 40), or duplex scan (n = 36). Long-term patencies were assessed in 14 patients monitored for 0.5 to 9 years (mean 3.2 years). RESULTS: Mechanisms of injury consisted of 58 gunshot wounds, 23 stab wounds, 6 shotgun wounds, and 5 blunt injuries. There were 112 associated injuries, 41 of which were concomitant arterial injuries. Forty-five of the 100 venous injuries were repaired with CVRs and included 6 (13%) spiral vein grafts, 8 (18%) panel vein grafts, 8 (18%) reversed saphenous vein interposition grafts, 8 (18%) end-to-end repairs, and 15 (33%) vein patch repairs. Thirty-day patency rates for these repairs were 50%, 50%, 75%, 88%, and 87%, respectively, and an overall patency rate of 73% was observed. The remaining 55 injuries were treated with ligation (n = 27) or lateral venorrhaphy (n = 28). The cumulative 30-day patency rate for all venous repairs was 81% (59 of 73). Fourteen patients, nine of whom had CVRs, were available for long-term follow-up. In this group CVRs demonstrated a 100% patency. One patient with a spiral vein graft repair of the common femoral vein had severe reflux causing intermittent edema and mild lipodermatosclerosis. No pulmonary emboli, limb loss, or deaths were identified in patients undergoing CVRs. CONCLUSION: Patients with CVRs had a 30-day patency rate of 73%. Of this group panel and spiral vein grafts were less successful, exhibiting only a 50% 30-day patency rate, whereas end-to-end and vein patch repairs were successful in 88% and 87% of cases, respectively. Our overall evaluation suggests that use of CVRs results in successful venous repair; however, the postoperative patency of interposition panel and spiral grafts suggests selective use of these techniques.

Adolescent↗
PubMed1997

Carotid arterial trauma: assessment with the Glasgow Coma Scale (GCS) as a guide to surgical management.

Management of carotid arterial injuries associated with focal neurological deficit or altered state of consciousness (SCON) remains unresolved. Experience with these injuries in one particular hospital was reviewed and the Glasgow Coma Scale (GCS) utilized to assist with clinical stratification of these patients. A literature review was also conducted to better define indications for repair or ligation of carotid injuries. From 1978 to 1990, 34 patients with carotid arterial injuries were reviewed with reference to the GCS, focal deficit, hypotension, anatomic site and mechanism of injury. The literature from 1952 to 1993 was surveyed for carotid artery injuries (1316 patients). Outcome of treatment with or without repair was compared with pre-operative neurologic status. Thirty-four patients with injuries of the common (24) or internal (10) carotid arteries were managed with repair (68%), ligation (24%) or observation (9%). The SCON was normal in 18 patients; 16 patients (88%) underwent repair and all remained normal. All patients with GCS 9-14 regained a normal SCON after surgical repair, while 10 patients with GCS < 8 had repair (5), ligation (3), and non-operative management (2); five returned to normal, four died and one remained comatose. However, outcomes correlated poorly with management. Of 1316 patients cited in the surgical literature, patients with no deficit and patients with pre-operative deficits did significantly better after repair as compared with ligation (P<0.001). In comatose patients, management did not affect outcome. It is concluded that carotid arterial injuries should be repaired in patients with normal neurologic evaluation, focal pre-operative neurologic deficits and in patients with GCS > 9. Comatose patients with GCS < 8 do poorly regardless of management. The GCS provides an objective for stratification of patients with altered SCON who benefit from repair of carotid arterial injuries.

Adult↗
PubMed1996

A program of operative angioplasty: endovascular intervention and the vascular surgeon.

PURPOSE: Vascular surgeons are ideally suited to select and perform endovascular interventions either as primary therapy or as an adjunct to bypass surgery. Attaining proficiency in endovascular techniques is an important goal in the training of vascular surgeons. We report our initial experience with a program of endovascular intervention performed in the operating room by vascular surgeons. METHODS: During the previous three years, we performed 109 angioplasty procedures, 60 aortoiliac (55%), 32 femoropopliteal (29%), and 17 popliteal/tibial (16%), using guidewires and angioplasty balloons directed by intraoperative digital subtraction C-arm arteriography with road-mapping capabilities. Indications for angioplasty included disabling claudication in 59 patients (54%), rest pain in 18 (17%), and tissue loss in 32 (29%). Angioplasty was accompanied by stent placement in 39 of 60 aortoiliac procedures (65%) and in two of 32 femoral procedures (6%). In 16 cases (15%), the endovascular procedure was performed in conjunction with a bypass procedure. In selected cases (15, 14%), duplex scanning was the sole diagnostic method used before surgery to identify the lesion, eliminating the need for preoperative arteriographic scans. Segmental pressure measurements, duplex ultrasound scans, and treadmill exercise testing as indicated were performed before and after surgery. The efficacy of the endovascular intervention was assessed at 3-month intervals during the first year and at 6-month intervals thereafter. RESULTS: A successful results was defined using criteria recommended by the Ad Hoc Subcommittee on Reporting Standards for Endovascular Procedures from the Society for Vascular Surgery/International Society for Cardiovascular Surgery. This included the combination of symptomatic improvement, obtaining an anatomically successful result with < 30% residual lumen stenosis, and elimination of the translesion gradient with an improvement in high thigh-brachial index or ankle-brachial index greater than 0.15. Initial success was achieved in 55 of 60 aortoiliac (92%), 28 of 32 femoropopliteal (88%), and 16 of 17 popliteal/tibial (94%) angioplasty procedures. Clinical follow-up has been achieved in all cases, with continued clinical success rates of 80%, 75%, and 82% for aortoiliac, femoropopliteal, and popliteal/tibial angioplasty procedures, respectively, with a mean follow-up of 15.7 months. CONCLUSION: These results confirm the value of a program in which C-arm technology was used by vascular surgeons in the performance of angioplasty and stenting procedures in the operating room. This experience in therapeutic endovascular intervention will facilitate the credentialing process for future vascular surgeons.

Aged↗
PubMed1994

The significance of calf muscle pump function in venous ulceration.

PURPOSE: Patients with clinically evident chronic venous insufficiency were evaluated to relate the degree of insufficiency and calf muscle pump dysfunction to venous ulceration. METHODS: Sixty-nine limbs in 55 patients with chronic venous insufficiency by Society for Vascular Surgery/International Society for Cardiovascular Surgery Classification were compared in three groups: classes 1 and 2 with no history of ulceration (19 limbs); class 3 with healed ulceration (20 limbs); and class 3 with active ulcers (30 limbs). Air plethysmography measurements of outflow fraction, venous volume, venous filling time, venous filling index, ejection fraction, ejection volume, residual volume fraction, and residual volume were made. In 62 of the 69 limbs, color-flow duplex ultrasonography was used to determine the pattern of reflux. RESULTS: The outflow fraction was normal in 84%, 75%, and 77% of nonulcerated, healed, and ulcerated limbs. The venous filling index was abnormal in most limbs (nonulcerated 95%, healed 90%, ulcerated 98%) but not significantly different among groups. Differences in calf muscle pump function were significant. Ulcerated limbs had significantly poorer ejection fractions (p = 0.0002) and greater residual volume fractions (p = 0.0006) than nonulcerated or healed limbs. By ultrasonography, deep and superficial vein incompetence was present in most limbs and was not statistically different among groups. Although venous insufficiency was not measurably different among groups, limbs with active venous ulcers had significantly poorer calf muscle pump function than those with healed ulcers or with no history of ulceration. CONCLUSION: Venous insufficiency is necessary but not sufficient to cause ulceration, and a deficiency of the calf muscle pump is significant to the severity of venous ulceration.

Adult↗
PubMed1991

Carotid endarterectomy for asymptomatic carotid stenosis: a ten-year experience with 120 procedures in a fellowship training program.

Performance of carotid endarterectomy for asymptomatic carotid stenosis has been restricted during recent years because of concern of reported complications in as high as 10-15% of patients, as well as limited long-term data on stroke protection. During the last 10 years, we have studied immediate and long-term results of carotid endarterectomy for asymptomatic disease in 120 patients. Operations were performed by a clinical vascular fellow with a staff surgeon in attendance in 113 (94%) cases with the remainder performed by the staff surgeon. Patients' mean age was 66 years; 82% were men. Risk factors included hypertension (56%), smoking (52%), coronary artery disease (32%), diabetes (24%), and hypercholesterolemia (6%). Arteriographic severity of stenoses was 80-99% in 74%, 60-79% in 22%, and 40-59% in 4% of cases. Postoperative complications included two transient neurological events (1.7%). No permanent strokes or deaths occurred. Using the life table method, cumulative stroke rate was 4.5% for ipsilateral events and 7.3% for contralateral events, confirming the high degree of stroke protection afforded by carotid endarterectomy in this population. Since these results were accomplished in a fellowship training program, we regard adequacy of this experience as the most influential factor in accomplishing this record. Surgeons who are unable to achieve comparable results should consider abandonment of the procedure or an extended period of additional training.

Aged↗
PubMed1991

Intravascular ultrasonography: validation studies and preliminary intraoperative observations.

Intravascular ultrasonography is emerging as an important imaging modality to assess the presence, distribution, and extent of atherosclerotic vascular disease. To determine the accuracy and clinical utility of intravascular ultrasonography, a flexible catheter-based system was used to generate two-dimensional, cross-sectional vascular images. In 23 arteries of 11 sheep 206 in vivo images demonstrated an echo-free lumen surrounded by three distinct concentric acoustic transitions corresponding to intima, media, and adventitia. Ultrasound measurements of lumen diameter and area correlated significantly with those of corresponding arteriographic measurements obtained by use of digital calipers (r = 0.91, r = 0.86). To evaluate clinical feasibility, intraoperative images (n = 160) were obtained in 10 patients undergoing vascular bypass or hemodialysis access procedures. The images depicted luminal configuration and arterial wall morphologic characteristics. Measurements of lumen diameter and lumen area correlated closely with corresponding intraoperative arteriography (r = 0.81, r = 0.79). The ultrasound images demonstrated arterial stenoses, intimal hyperplasia, intraluminal thrombus, polytetrafluoroethylene graft material, and anastomotic sites. We conclude that flexible catheter-based ultrasonography produces images that accurately demonstrate arterial wall architecture, lumen diameter, and area. Intraoperative application can produce images that provide unique information thus expanding the clinical potential of ultrasonography as a guidance system for vascular procedures.

Animals↗
PubMed1990

Diagnosis of acute deep venous thrombosis.

This article outlines the application of continuous-wave Doppler, plethysmographic techniques, and B-mode ultrasonography to the diagnosis of suspected deep venous thrombosis in ambulatory patients. Methodology is evaluated, and the diagnostic accuracy and application of these studies are reviewed. The authors' current algorithm for the application of these noninvasive studies also is presented.

Humans↗
PubMed1990

Reduced dependency on arteriography for penetrating extremity trauma: influence of wound location and noninvasive vascular studies.

Indications for arteriography in penetrating extremity trauma remain controversial. We reviewed our clinical experience in 454 patients (514 extremities) with penetrating trauma admitted during a prior 3 1/2-year period. Injuries were caused by stab wounds in 60 (11.7%) extremities and by gunshot wounds in 454 (88.3%) extremities. Thirty-three of the 60 stab wounds (55%) required urgent exploration, and 27 underwent arteriography. No arteriograms were positive for unsuspected arterial injury in this group. Forty-two of 454 gunshot wounds (9.3%) underwent mandatory exploration; arteriograms were performed on 412 extremities. Forty-four arteriograms (10.7%) demonstrated evidence of unsuspected arterial injuries. During the last year, randomly selected extremities (n = 23) have been studied with B-mode ultrasonography and segmental Doppler pressure measurements. Using the subsequent arteriography as the "gold" standard, sensitivity was 83% and specificity was 100%. Gunshot wounds were categorized according to location and positive arteriograms. Injuries to the lateral thigh and arm resulted in no positive arteriograms, while positive studies were observed in 11% of medial and posterior arm, 14% of antecubital fossa, 25% of forearm, 7.5% of medial and posterior thigh, 8% of popliteal fossa, and 26% of calf injuries. We recommend arteriography for gunshot injuries to identified high-risk areas, while clinical evaluation alone is accurate in all stab wounds to the extremities and gunshot wounds to the lateral thigh and outer arm. Preliminary data suggest expanded use of B-mode ultrasonography may further reduce our dependency on arteriography in these cases.

Adolescent↗
PubMed1990

Penetrating extremity trauma: identification of patients at high-risk requiring arteriography.

Indications for arteriography in patients with penetrating trauma to the extremities remain controversial. Some clinicians have recommended universal use of arteriography, whereas others prefer to rely on physical findings alone. To better define our indications for contrast studies, we reviewed clinical data on 306 patients (349 extremities) with penetrating trauma who were admitted during a prior 2-year period (1985 to 1987). Injuries were caused by stab wounds in 50 (14.3%) extremities and by gunshot wounds in 299 (85.7%) extremities. Twenty-seven of the 50 stab wounds (54%) required urgent exploration based on physical findings, whereas 23 underwent arteriography. None of these studies showed unsuspected arterial injury. Twenty-nine of 299 gunshot wounds (9.7%) underwent mandatory exploration, and arteriograms were performed on 270 extremities; findings in 30 studies (11.1%) were positive for unsuspected arterial injuries. Gunshot wounds were categorized according to location and number of arteriograms with positive results. Arteriograms of lateral thigh and upper arm injuries resulted in no positive outcomes. Positive study results were recorded in 22.9% of calf injuries, 20% of forearm and antecubital injuries, 9.5% of popliteal fossa injuries, 9.0% of medial and posterior thigh injuries, and 8.3% of medial and posterior upper arm injuries. We recommend arteriography for penetrating injuries to these high-risk areas. However, clinical evaluation alone is accurate for identification of arterial trauma with lateral thigh or upper arm wounds and stab wounds to the extremities.

Adolescent↗