Current developments in endovascular in situ bypass grafting.
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Angioscopy↗
Biomedical subjects
D Rosenthal
Publications and source records attributed to D Rosenthal.
Minimally invasive in situ bypass.
Since the report of a successful femoropopliteal in situ saphenous vein bypass in 1962, surgeons have attempted to make this bypass a less invasive operation and simplify the two principal technical components of the operation: (1) rendering the saphenous vein valves incompetent and (2) occluding the venous side branches. To accomplish this bypass, however, a long incision that is the length of the leg over the course of the saphenous vein is often necessary, which can be fraught with hazard, especially in patients with diabetes in whom wound complications can be devastating. An angioscopically assisted technique that allows the surgeon to perform valvulotomy and occlude venous side branches from within the saphenous vein--a minimally invasive in situ vein bypass--has been developed. This article discusses preclinical, fluoroscopic clinical, and angioscopic clinical studies of minimally invasive in situ bypass.
Animals↗
Spinal cord ischemia after abdominal aortic operation: is it preventable?
PURPOSE: Spinal cord ischemia after operation on the abdominal aorta is a rare event that is attributed to variations in the spinal cord blood supply. The purpose of this study was to evaluate the possible causes of this devastating event. METHODS: A survey of patients among the members of the Southern Association for Vascular Surgery was performed, and 18 patients were identified with spinal cord ischemia manifested by paraplegia or paraparesis after abdominal aortic operation. RESULTS: Preoperative computed tomographic, magnetic resonance, and aortographic results did not visualize the greater radicular artery (Adamkiewicz's artery) in any patient. Eleven patients underwent resection of infrarenal abdominal aortic aneurysms (AAAs): seven of these patients had tube grafts, three had aortobifemoral grafts, and one had an aortobiiliac graft. Five other patients underwent placement of aortobifemoral grafts, and one patient underwent aortobiiliac graft placement for occlusive disease. One patient underwent suprarenal AAA resection with an interposition graft to a previous aortobiiliac graft. The mean operative time was 3 hours and 39 minutes (range, 2 hours and 45 minutes to 6 hours and 30 minutes), with a mean aortic cross-clamp time of 48 minutes (range, 24 to 97 minutes). Sixteen aortic cross-clamps were placed infrarenally and two suprarenally (one in a case of ruptured AAA, the other a suprarenal AAA). Seventeen proximal anastomoses were end to end. The average minimum systolic blood pressure during the aortic cross-clamping was 96 mm Hg (range, 80 to 130 mm Hg). All the patients had internal iliac artery flow preserved with either prograde perfusion (10 patients) or retrograde perfusion (eight patients), and one patient underwent unilateral internal iliac artery ligation because of aneurysmal disease. One aortobifemoral-graft limb necessitated thrombectomy, but no cases of massive peripheral embolization occurred. When paraplegia was suspected after operation (6 to 20 hours after surgery), five patients underwent lumbar drainage. No clinical improvement was noted. CONCLUSION: Interference with pelvic blood supply from prolonged aortic cross clamping, intraoperative hypotension, aortic embolization, and interruption of internal iliac artery circulation have all been suggested as possible causes of spinal cord ischemia. In this survey, none of these factors proved to be significant as the sole cause of spinal cord ischemia. In the performance of an aortic operation with an end-to-end proximal anastomosis in the presence of severe external or internal iliac artery disease, there may be an increased incidence of spinal cord ischemia despite appropriate surgical techniques to ensure internal iliac perfusion. Spinal cord ischemia after abdominal aortic operations appears to be a tragically unpredictable, random, and unpreventable event.
Anastomosis, Surgical↗
Comparison between the transabdominal and retroperitoneal approaches for aortic reconstruction in patients at high risk.
PURPOSE: The purpose of this study was to compare the transabdominal approach with the retroperitoneal approach for elective aortic reconstruction in the patient who is at high risk. METHODS: From January 1992 through January 1997, 148 patients underwent aortic operations: 92 of the patients were classified as American Society of Anesthesia (ASA) class IV. Forty-four operations on the patients of ASA class IV were performed with the transabdominal approach (25 for abdominal aortic aneurysms and 19 for aortoiliac occlusive disease), and 48 operations were performed with the retroperitoneal approach (27 for abdominal aortic aneurysms and 21 for aortoiliac occlusive disease). There were no significant differences between the groups for comorbid risk factors or perioperative care. RESULTS: Among the patients of ASA class IV, eight (8.7%) died after operation (retroperitoneal, 3 [6.26%]; transabdominal, 5 [11.3%]; P =.5). There was no difference between groups in the number of pulmonary complications (retroperitoneal, 23 [47.9%]; transabdominal, 19 [43.2%]; P =.7) or in the development of incisional hernias (retroperitoneal, 6 [12.5%]; transabdominal, 5 [11.3%]; P =.5). The retroperitoneal approach was associated with a significant reduction in cardiac complications (retroperitoneal, 6 [12.5%]; transabdominal, 10 [22.7%]; P =.004) and in gastrointestinal complications (retroperitoneal, 5 [8.3%]; transabdominal, 15 [34.1%]). Operative time was significantly longer in the retroperitoneal group (retroperitoneal, 3.35 hours; transabdominal, 2.98 hours; P =.006), as was blood loss (retroperitoneal, 803 mL; transabdominal, 647 mL; P =.012). The patients in the retroperitoneal group required less intravenous narcotics (retroperitoneal, 36.6 +/- 21 mg; transabdominal, 49.5 +/- 28.5 mg; P =.004) and less epidural analgesics (retroperitoneal, 39.5 +/- 6.4 mg; transabdominal, 56.6 +/- 9.5 mg; P =.004). Hospital length of stay (retroperitoneal, 7.2 +/- 1.6 days; transabdominal, 12.8 +/- 2.3 days; P =.024) and hospital charges (retroperitoneal, $35,587 +/- $980; transabdominal, $54,832 +/- $1105; P =.04) were significantly lower in the retroperitoneal group. The survival rates at the 40-month follow-up period were similar between the groups (retroperitoneal, 81.3%; transabdominal, 78.7%; P =.53). CONCLUSION: In this subset of patients who were at high risk for aortic reconstruction, the postoperative complications were common. However, the number of complications was significantly lower in the retroperitoneal group. Aortic reconstruction in patients of ASA class IV appears to be more safely and economically performed with the retroperitoneal approach.
Abdomen↗
Quantitative assessment of cross-sectional muscle area, functional status, and muscle strength in men with the acquired immunodeficiency syndrome wasting syndrome.
The acquired immunodeficiency syndrome wasting syndrome (AWS) in men is characterized by the loss of lean body mass out of proportion to weight. Although the wasting syndrome has been thought to contribute to reduced functional capacity, the relationships among lean body mass, muscle size, functional status, and regional muscle strength have not previously been investigated in this population. In this study, 24 eugonadal men with the AWS (weight <90% of the ideal body weight or weight loss >10% from preillness maximum) underwent determination of body composition by dual energy x-ray absorptiometry (DXA), 40K isotope analysis, urinary creatinine excretion, and quantitative computed tomographic analysis of cross-sectional muscle areas of the midarm and thigh. Overall exercise functional capacity was evaluated using the 6-min walk test, and performance of upper and lower extremities was determined with the quantitative muscle function test. Subjects were 37 +/- 1 yr of age and weighed 95.5 +/- 3.0% of ideal body weight, with a body mass index of 21.9 +/- 0.7 kg/m2 and an average weight loss of 15 +/- 1%. The mean CD4 count among the subjects was 354 +/- 70 cells/mm3, and viral load was 58,561 +/- 32,205 copies. Sixty-two percent of subjects were receiving protease inhibitor therapy. The subjects demonstrated 90% of the expected muscle mass by the creatinine height index method. Overall performance status on the Karnofsky scale was highly correlated to weight (r = 0.51; P = 0.018; by body mass index), lean body mass (r = 0.46; P = 0.036; by DXA), and body cell mass (r = 0.47; P = 0.037; by 40K isotope analysis). Cross-sectional muscle area of the upper extremity was the best predictor (P < 0.001) of Karnofsky score, accounting for 52% of the variability in a stepwise regression analysis. Upper body muscle strength was most significantly predicted by lean body mass (by DXA; r2 = 0.78; P < 0.0001), whereas lower body strength and performance on the 6-min walk test were best predicted by lower extremity cross-sectional muscle area (r2 = 0.70; P < 0.0001 and r2 = 0.26; P = 0.030, respectively). These data demonstrate that cross-sectional muscle area is highly predictive of functional status and muscle strength in men with the AWS.
Adult↗
Representations of reproductive technology in women's narratives of infertility.
This paper explores the ways in which the notion of reproductive technology is represented in the narratives of infertility told by a sample of Australian women. These narratives suggest that reproductive technology has been configured as the alternative instrument in realising the quest for a child. Because reproductive technology was represented in complex and changing ways in the narratives of individual women, it would have been inappropriate to divide the women into two groups as users and non-users of reproductive technology. The women were consulted at each stage of the research to ensure that what was inferred from their stories remained true to their narrative construction of themselves.
Adult↗
Reoperation for herniated thoracic discs.
OBJECT: In this review the authors address the surgical strategies required to resect residual herniated thoracic discs. METHODS: Data obtained in 15 patients who had undergone prior thoracic discectomy and who harbored residual or incompletely excised symptomatic thoracic discs were reviewed retrospectively. The surgical procedures that had failed to excise the herniated discs completely included 11 posterolateral approaches, one thoracotomy, and three thoracoscopy-guided surgical procedures. Of the lesions that were incompletely resected or residual, there were 13 central calcified, two soft. 12 extradural, and three intradural discs. Indications for reoperation were often multiple in each patient and included misidentification of the level of disc disease at the initial operation (five cases), abandoning the procedure because of intraoperative spinal cord injury (three cases), inadequate visualization of the pathological entity (eight cases), migration of a soft disc fragment within the spinal canal (one case), and intradural disc extension (three cases). The symptoms at the time of reoperation included myelopathy in 13 patients and radicular pain in two patients. The mean interval before reoperation was 150 days (range 1 day-4 years). The reoperation procedures included one thoracotomy and 14 video-assisted thoracoscopic procedures performed ipsilateral (11 cases) or contralateral (four cases) to the site of the initial surgery. The herniated disc material was excised completely in all 15 cases without causing new neurological deficits. Reoperation complications included atelectasis in three patients, intercostal neuralgia in two, a loosened screw that required removal in one, residual intradural disc herniation that required a second reoperation in one patient, and a cerebrospinal fluid leak in one patient. Of the 13 patients who experienced myelopathy prior to operation, 10 recovered neurological function and three stabilized. All patients with radicular pain improved. CONCLUSIONS: Calcified, large, broad-based, centrally located, or transdural thoracic disc herniations can be difficult to resect. These lesions require a ventral operative approach to visualize the dura adequately for a safe and complete resection.
Calcinosis↗
Irreversible binding of poly(ADP)ribose polymerase cleavage product to DNA ends revealed by atomic force microscopy: possible role in apoptosis.
During apoptosis, DNA undergoes fragmentation and caspase-3 cleaves poly(ADP-ribose) polymerase (PARP) into both a 24-kDa fragment containing the DNA binding domain and an 89-kDa fragment containing the catalytic and automodification domains. Atomic force microscopy revealed that recombinant full-length PARP bound to plasmid DNA fragments and linked them into chainlike structures. Automodification of PARP in the presence of NAD+ resulted in its dissociation from the DNA fragments, which, nevertheless, remained physically aligned. A recombinant 28-kDa fragment of PARP containing the DNA binding domain but lacking the automodification domain irreversibly bound to and linked DNA fragments in the absence or presence of NAD+. Identical results were obtained on incubation of internucleosomal DNA fragments from apoptotic cells with the products of cleavage of recombinant PARP by purified caspase-3. The 24-kDa product of PARP cleavage by caspase-3 may contribute to the irreversibility of apoptosis by blocking the access of DNA repair enzymes to DNA strand breaks.
Animals↗
A challenging question regarding the use of topical corticosteroids for mycosis fungoides.
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Administration, Topical↗
Assessing outcomes, costs, and benefits of emerging technology for minimally invasive saphenous vein in situ distal arterial bypasses.
BACKGROUND: Instrumentation for a minimally invasive angioscopic in situ peripheral arterial bypass (MIAB) with catheter-directed side-branch occlusion has recently been approved for use. Despite the attractiveness of this approach (2 short incisions), benefits such as lower morbidity and shorter hospitalizations remain undocumented. To justify wide acceptance, minimally invasive surgical techniques must match conventional procedures in durability and cost while enhancing patient comfort. Often such comparisons are difficult during the implementation phase of a new procedure. OBJECTIVE: To compare the outcomes of the MIAB procedures with a concurrent group of patients undergoing conventional in situ bypass procedures. DESIGN: Retrospective review. SETTING: University medical center. PATIENT: The first 20 consecutive MIAB procedures in 19 patients performed between August 1, 1995, and July 31, 1997, were compared with 19 contemporaneous consecutive conventional in situ bypass procedures performed at the same institution. MAIN OUTCOME MEASURES: Operative time, postoperative length of stay, hospital costs, complications, primary assisted and secondary patency, limb salvage, and survival. RESULTS: The patient groups were comparable with respect to age, sex, incidence of smoking, coronary artery disease, hypertension, diabetes, renal failure, cerebrovascular disease, indication, and distal anastomosis level. The median operative time was significantly greater for the MIAB group (6.6 hours vs 5.7 hours; P=.009), and intraoperative completion arteriography more frequently showed retained arteriovenous fistulas in the MIAB group (55% vs 21%; P=.05). The median postoperative length of stay and total cost were 6.5 days and $18,000 for the MIAB group and 8 days and $27,800 for the conventional group (P > or = .05). There were no significant differences in major complications (10% in the MIAB group vs 11% in the conventional group), wound complications (10% vs 11%, respectively), primary assisted patency at 1 year (68%+/-11% vs 78%+/-10%, respectively), secondary patency at 1 year (79%+/-10% vs 88%+/-8%, respectively), limb salvage at 1 year (85%+/-10% vs 94%+/-6%, respectively), or patient survival at 1 year (89%+/-8% vs 61%+/-13%, respectively). CONCLUSION: Patients undergoing the MIAB procedure avoided lengthy vein exposure incisions without sacrificing short-term results. There was a trend toward decreased hospital stay and cost, which may be further realized as the clinical experience broadens. Although longer follow-up and larger cohorts will always be required to define durability, immediate access to outcomes and costs on small numbers of patients facilitates the early assessment of emerging technology.
Adult↗
PSA immunoreactivity in a parotid oncocytoma: a diagnostic pitfall in discriminating primary parotid neoplasms from metastatic prostate cancer.
Prostate-specific antigen (PSA) is secreted by both normal and neoplastic acinar cells of the prostate gland, and the immunohistochemical detection of PSA is widely accepted as an excellent method for confirming the prostatic origin of metastatic tumor implants in men with prostate cancer. Less recognized is the observation that certain nonprostatic tissues and their neoplastic counterparts also secrete PSA. As one example, salivary gland ducts and certain salivary gland neoplasms have been reported to be immunoreactive for PSA. Potentially, this nonspecificity could be a diagnostic pitfall when using immunoperoxidase on fine-needle aspiration (FNA) biopsy specimens to differentiate metastatic prostate cancer from primary salivary gland tumors. We report on a case where strong PSA immunoreactivity of a parotid oncocytoma led to its confusion with metastatic prostate cancer.
Acid Phosphatase↗
Voice recognition--an emerging necessity within radiology: experiences of the Massachusetts General Hospital.
Voice recognition represents a technology that is finally ready for prime time use. As radiology services continue to acquire a larger percentage of the shrinking health-care dollar, decreasing operating costs and improved services will become a necessity. The benefits of voice recognition implementation are significant, as are the challenges. This report will discuss the technology, experiences of major health-care institution with implementation, and potential benefits for the radiology practice.
Humans↗
Diagnosis of aortocaval fistula by computed tomography.
A case of an aortocaval fistula documented by contrast-enhancement computed tomography is reported. In the presence of a large abdominal aortic aneurysm, the computed tomography (CT) triad findings of: (1) vena caval effacement, (2) loss of the fat plane between the aorta and vena cava, and (3) rapid flow of contrast from the aorta into a dilated inferior vena cava is characteristic of an aortocaval fistula.
Aged↗
The valvular apparatus in venous insufficiency: a problem of quantity?
Abnormal venous valvular function may produce venous reflux and venous insufficiency. While valvular agenesis is a known, but rare cause of venous insufficiency. While valvular agenesis is a known, but rare cause of venous insufficiency, little work has been done on the relative number of greater saphenous vein (GSV) valves in patients with venous insufficiency. This study investigates whether the GSV in patients with symptomatic venous insufficiency has fewer valves than the GSV of patients without venous insufficiency. The number of GSV valves in patients (n = 51) with symptomatic venous insufficiency undergoing saphenectomy (VI) were compared with the number of GSV valves in patients (n = 26) without venous insufficiency undergoing in situ GSV bypass under angioscopic surveillance who served as a control group. The two groups differed, as expected, in age and sex distribution. The VI group had a mean of 25.7 +/- 11.0 centimeters of GSV between valves, while the control group had 19.0 +/- 9.7 centimeters of GSV between valves (F = 6.99; p = 0.01). The mean number of valves in the saphenous veins of the two groups also differed significantly: VI = 2.3 +/- 0.83 versus control (CTRL) = 4.8 +/- 2.01 (F = 61.86; p < 0.0001). That properly functioning valve leaflets help maintain physiologic antegrade venous flow is indisputable. This study, however, suggests that the relative lack of valves may be related to the development of venous insufficiency. This report documents that patients with symptomatic reflux in the GSV have significantly fewer valves than patients with apparently normal functioning saphenous veins.
Adult↗
Transposed basilic vein versus polytetrafluorethylene for brachial-axillary arteriovenous fistulas.
BACKGROUND: Both transposed basilic vein (BV) and polytetrafluorethylene (PTFE) upper arm arteriovenous fistulas (AVF) are common angioaccess operations. To evaluate the patency and complication rates after AVF, a concurrent series of patients was reviewed. METHODS: Ninety-eight patients underwent brachial artery to axillary vein AVF: 30 BV and 68 PTFE. The PTFE grafts were performed in the standard fashion, whereas the basilic veins were translocated subcutaneously to the brachial artery. RESULTS: Risk factors were similar between the two groups. Basilic vein AVF had better patency at 24 months (70% BV versus 46% PTFE, P = 0.023). The dialysis access complications were higher in the BV group (20%) versus PTFE (5%), but the PTFE group had a higher infection rate (10%) than BV (0%). CONCLUSIONS: The primary and secondary patency rates were superior in the BV AVFs. The BV AVF preserves the venous outflow tract after AVF thrombosis for a future PTFE AVF operation.
Arteriovenous Shunt, Surgical↗
A new therapeutic approach to the fetus with congenital complete heart block: preemptive, targeted therapy with dexamethasone.
BACKGROUND: Therapy of established congenital complete heart block in the fetus has resulted in improved survival but persistence of heart block. This exposes the infant to the morbidity of heart block, including the risk of sudden death and pacemaker implantation. CASE: A 35-year-old gravida 2, para 1, with Sjogren syndrome and a previous pregnancy complicated by congenital complete heart block presented during her second pregnancy. Intensive fetal monitoring with echocardiography was employed. Early evidence of myocardial dysfunction and dysrhythmia was found, dexamethasone therapy was initiated, and the dysfunction and dysrhythmia resolved. The pregnancy went to term without further complication. CONCLUSION: This represents a new and successful strategy to identify very early signs of myocardial disease in a fetus at high risk of congenital complete heart block, enabling targeted, preemptive therapy.
Adult↗
Northern blot identification of mRNA containing sequence for protein allergen, Alt a1, in eight strains of Alternaria alternata.
BACKGROUND: Concentrations of Alt a1, a major allergen from Alternaria alternata extracts, exhibit significant batch-to-batch variability. This variability may result from basic strain-related genetic differences or from environmental influences such as growth conditions or extraction methods. OBJECTIVE: The objective of this work is to determine if strain-to-strain allergen variability in Alternaria alternata, Alt a1 allergen occurs at the nucleic acid level. METHODS: We compared the content of mRNA for a segment known to contain sequence coding for the reported N-termini of this allergen in eight strains of Alternaria obtained from three individual sources grown under identical conditions. RNA was extracted from rapidly growing mycelia and analyzed by northern blot analysis for the content of a specific segment containing sequence for the Alt a1 allergen. Blots were also analyzed for the content of a specific 5.8S rRNA segment. RESULTS: The size of the mRNA for this protein was about 700 bases. Sequence for the specific segment was found in all of the eight strains tested. When normalized for extraction variabilities using the content of 5.8S rRNA, the calculated concentrations of Alt a1 mRNA of seven of the eight strains were similar. CONCLUSIONS: The results of these experiments suggest that this Alt a1 related allergen sequence is found in many strains of Alternaria and that variabilities in allergen protein content noted previously result from posttranslational events.
Allergens↗