John Thomas Mehigan

Measurement of collateral cerebral hemispheric blood pressure by ocular pneumoplethysmography

A new technic of ocular pneumoplethysmorgraphy for the simultaneous determination of blood pressures in the ophthalmic artery branches of the internal carotid arteries is described. It provides a noninvasive, atraumatic method for assessing hemispheric blood flow. When performed with simultaneous carotid compression, it provides a means for assessing the availability of collateral blood flow to the ipsilateral cerebral hemisphere. Clinical applications related to carotid artery disease and carotid artery surgery are discussed.

Early experience with cryopreserved saphenous vein allografts as a conduit for complex limb-salvage procedures

PURPOSE The lack of a suitable alternative to autogenous vein is often the limiting factor for complex lower extremity vascular reconstruction, especially when previously placed grafts have failed. Cryopreserved saphenous vein allografts have been used as an alternative conduit. This report reviews our early experience with this conduit in a series of complex redo revascularization procedures for limb salvage when no suitable autogenous vein was available. METHODS Thirty-five patients underwent 39 lower extremity bypass grafts on 36 limbs. These patients had undergone a combined total of 72 prior revascularization procedures on the symptomatic limb, an average of two procedures per patient. Only five bypasses were performed as a primary procedure. There were 18 men and 17 women with a mean age of 71 years. Sixteen of the patients had diabetes. Thirty-four bypasses were performed for rest pain or ulceration, four for disabling claudication, and one for replacement of an aneurysmal vein graft. There were 35 femorotibial, three below-knee femoropopliteal, and one femoropedal reconstruction. Twenty-five grafts were constructed with cryopreserved vein only, whereas 14 were composite grafts; 10 were constructed with polytetrafluoroethylene, one with Dacron, and three with spliced native saphenous vein. The mean follow-up was 9 months (range 1 to 25 months). RESULTS There was one early death (< 30 days) and two late deaths. Two patients died with a patent graft. There have been 12 early graft closures and an additional 17 late failures, resulting in primary cumulative graft patency rates of 67%, 56%, 43%, 28%, and 14% at 1, 3, 6, 12, and 18 months, respectively. Surgically correctable causes, including technical error and anastomotic stenosis, could be identified in 13 of the 29 graft failures. Salvage of failed grafts resulted in secondary cumulative graft patency rates of 87%, 77%, 61%, 46%, and 37% at these same intervals. There was no significant difference in primary or secondary graft patency rates related to diabetes, ABO graft compatibility, graft composition or orientation, indication for surgery, state of the outflow tract, or site of distal anastomosis. Limb salvage was attained in 24 (67%) of the 36 limbs. Two amputations were necessary despite patent grafts. CONCLUSIONS Because of the poor overall graft patency rates, cryopreserved saphenous vein allografts should be used only as a last resort when no alternative autogenous conduit is available. Unless patency rates superior to those achievable with currently available prosthetic or biologic conduits can be attained by adjunctive measures such as routine anticoagulation or immunosuppressive therapy, the use of cryopreserved saphenous vein allografts for lower extremity revascularization should be deferred until improved preparation techniques provide a more durable conduit.

Selective absorption of ultraviolet laser energy by human atherosclerotic plaque treated with tetracycline

Tetracycline is an antibiotic that absorbs ultraviolet light at 355 nm and preferentially binds to atherosclerotic plaque both in vitro and in vivo. Tetracycline-treated human cadaveric aorta was compared with untreated aorta using several techniques: absorptive spectrophotometry, which demonstrated a distinct absorptive peak at 355 nm in tetracycline-treated plaque that was absent in treated normal vessel; ultraviolet microscopy, which showed that treated atheroma acquired the characteristic fluorescence of tetracycline under ultraviolet light; and tissue uptake of radiolabeled tetracycline, which showed 4-fold greater uptake by atheroma than by normal vessel. In addition, intravenous tetracycline administered to patients undergoing vascular surgery demonstrated characteristic fluorescence in surgically excised diseased arteries. Because of tetracyclines unique properties, we exposed tetracycline-treated and untreated aorta to ultraviolet laser radiation at a wavelength of 355 nm. We found enhanced ablation of tetracycline-treated atheroma compared with untreated atheroma. The plaque ablation caused by ultraviolet laser radiation was twice as extensive in tetracycline-treated vs nontreated plaque (2.2 +/- 0.25 mm vs 1.3 +/- 0.55 mm, p less than 0.017). This study demonstrates the potential of tetracycline plaque enhancement for the selective destruction of atheroma by ultraviolet laser radiation.

Continuous ambulatory peritoneal dialysis. Technique of catheter insertion and management of associated surgical complications.

Fifty-seven patients initiated continuous ambulatory peritoneal dialysis. All patients were generally pleased with this form of dialysis and particularly enjoyed the greater mobility and decreased dietary restriction. Complications associated with continuous ambulatory peritoneal dialysis include peritonitis, pericatheter infection, catheter malfunction, dialysate leak, and hernias of the abdominal wall.

Video angioscopy as an alternative to intraoperative arteriography

Improved technology has made available the technique of video angioscopy. When applied routinely, it can provide a high yield of important technical detail in a graphically precise and easily applicable manner, at the time of a great variety of vascular reconstructions, and complications are rare. Although not entirely replacing intraoperative arteriography, its multiple attractive characteristics make it substantially more useful in many circumstances. Familiarity with the technique will enable vascular surgeons to more rapidly utilize new methods of therapy, such as lasers, as well as improve already existing ones.

Diffuse arterial narrowing as a result of intimal proliferation: A delayed complication of embolectomy with the Fogarty balloon catheter ☆ ☆☆

Most complications of embolectomy with the Fogarty balloon catheter are recognized early and have received ample attention in the surgical and radiologic literature. However, the delayed complication of diffuse arterial narrowing causing severe ischemia has received little emphasis, perhaps because follow-up arteriography is not always performed. This report describes five patients--women 43 to 62 years of age--with progressive leg ischemia discovered 2 to 4 months after embolectomy with the balloon catheter. Angiography showed a characteristic pattern of severe, smooth narrowing of that portion of the artery in which balloon embolectomy was performed. Pathologic examination of arterial specimens, available in two of the five patients, revealed marked intimal cellular proliferation, which narrowed the arteries severely without evidence of thrombosis, significant atheromatosis, or active arteritis. The cause appears to be intimal damage by the balloon. Embolectomy with the balloon catheter should be done especially carefully in relatively young women.

Lower extremity atheromatous embolization.

Eleven patients with lower extremity atheromatous microembolization are described. The diagnostic feature of sudden, often repetitive, episodes of focal ischemia, patent major arteries of the legs, and arteriographic demonstration of nonocclusive atheromas of the proximal arterial tree are characteristic. Successful removal of the causative lesion in these patients has prevented further ischemic episodes.

Planned approach to the management of malignant invasion of the carotid artery.

A planned approach to the evaluation and management of patients with tumor involvement of the cervical carotid artery is presented. Preoperative arteriography and determination of carotid back-pressure permitted a rational approach in these high risk patients. One patient found to have an extremely low carotid back-pressure was advised not to undergo carotid resection. Six patients with satisfactory carotid back-pressure tolerated carotid resection and reconstruction.

Subclavian-carotid transposition for the subclavian steal syndrome

The clinical experience with twelve patients who underwent subclavian-carotid transposition for the subclavian steal syndrome is related. The technical details of the procedure as well as the satisfactory clinical results are described, and the characteristics making it out procedure of choice are summarized.

Snuffbox arteriovenous fistula for hemodialysis

Abstract Blood access for hemodialysis by means of an autogenous fistula placed in the anatomic snuffbox location is described. Because of anatomic differences, this location is preferred to that of the traditional Brescia-Cimino fistula.