Noninvasive vascular imaging in the diagnosis and treatment of adventitial cystic disease of the popliteal artery.

This brief case report describes the successful outcome after surgical excision of multiple adventitial cysts of the popliteal artery in a 75-year-old man with rapidly worsening claudication. It highlights several unsettled points concerning the diagnosis, cause, and management of cystic adventitial disease of the popliteal artery and compares duplex ultrasound, computed tomography, and magnetic resonance angiography in the noninvasive diagnosis and treatment of this condition.

Strategies to increase the use of autogenous arteriovenous fistula in end-stage renal disease.

The purpose of this retrospective study was to review our experience with a consecutive group of end-stage renal disease (ESRD) patients using simple strategies to increase the use of autogenous vascular access, and determine whether the current trend of using synthetic bridge-graft fistula (BGF) rather than autogenous arteriovenous fistula (AVF), could be reversed, despite an aging population and broadening criteria for hemodialysis. All patients for vascular access surgery had careful preoperative clinical examination of the arm veins with outflow occlusion to determine the venous anatomy and continuity. Where no veins were apparent or their continuity in doubt, selective preoperative venography was performed. Where veins were unsatisfactory for forearm AVF, new or modified surgical procedures to use both the basilic and cephalic veins in the upper arm were performed. Intraoperative angioscopy was used to monitor vein quality and surgical technique. Ninety-eight primary vascular access procedures were performed in 76 patients, 75 (76.5%) AVF (forearm, n = 41; upper arm, n = 34) and 23 (23.5%) BGF. Forty-one of 76 (54%) had already had at least one previous access procedure prior to this study. More than one access procedure was needed in 16 patients. Preoperative venography was performed in 22 (22.4%) and intraoperative angioscopy in 45 (45.9%) of the 98 procedures. The number of revisions required to maintain patency was significantly higher for BGF (37 revisions in 14/23) than AVF (16 revisions in 13/75) (p < 0.0001, Poisson test) with an annualized secondary revision rate of 1.168 for BGF and 0.173 for AVF (p < 0.0001, Poisson test). AVF had both longer primary (p = 0.0001, log rank test) and secondary patency (p = 0.038, log rank test) than BGF. AVF as the primary vascular access can be significantly increased and the current trend of using BGF reversed with the use of simple clinical strategies to evaluate the suitability of the arm veins for vascular access.

Diagnosis of parathyroid adenomas: efficacy of measuring parathormone levels in needle aspirates of cervical masses.

OBJECTIVE: The purpose of this study was to assess the value of measuring parathormone levels in percutaneous needle aspirates of suspicious cervical lesions in patients with hyperparathyroidism to confirm whether the lesion represents abnormal parathyroid tissue. SUBJECTS AND METHODS: The study group consisted of 66 patients with hyperparathyroidism in whom 80 cervical lesions were aspirated and levels of parathormone in the aspirates were measured. CT guidance was used for two patients and sonographic guidance for the remainder. The lesions selected for aspiration were demonstrated on either sonography or CT and had either an unusual position (separate from the thyroid gland or were intrathyroidal) or configuration (irregular shape or atypical heterogeneous sonographic texture). In 15 patients, an indeterminate, posteriorly located intrathyroidal mass was detected and felt most likely to represent a thyroid nodule by sonographic criteria. These masses were aspirated to rule out atypical parathyroid adenomas. In patients who had been previously explored for hyperparathyroidism and presented with persistent or recurrent hypercalcemia, all indeterminate, cervical, potentially parathyroid masses were aspirated for parathormone determination. The level of parathormone in each aspirate was measured by using an immunoradiometric assay. RESULTS: Levels of parathormone were increased in the aspirates in 37 of the 45 patients in whom sonography showed classic lesions suggestive of parathyroid adenoma. This included the 25 patients who had previously undergone exploratory surgery. At surgery, all 37 had parathyroid adenomas in the indicated locations, for a specificity of 100%. In six patients, the results of the aspiration were false-negative. Parathyroid adenomas were suspected on sonograms and confirmed at surgery, but no parathormone was detected in the aspirate. Results of aspiration of indeterminate lesions were true-negative in two patients who had both characteristic and indeterminate lesions on sonography and in the 15 patients who had indeterminate lesions that were felt to be of thyroid origin. Aspirates contained no parathormone, and surgical findings confirmed the lesions were not of parathyroid origin. CONCLUSION: Our results show that increased levels of parathormone in percutaneous needle aspirates of cervical masses in patients with hyperparathyroidism confirm the mass is a parathyroid adenoma. Although absence or low levels of parathormone in the aspirates usually excludes a parathyroid adenoma, this is not absolute as sometimes the needle may miss the mass, rendering the parathormone value invalid (false-negative).

Arteriographic ablation of cervical parathyroid adenomas.

In some cases of primary hyperparathyroidism, in particular where neck exploration has been unsuccessful, an alternative to surgical therapy may be desirable. We studied the acute and chronic metabolic effects of attempted angiographic destruction by angiographic contrast infusion of solitary parathyroid adenomas in 18 patients with symptomatic disease. Fourteen patients had failed prior surgery; 4 patients had not undergone prior surgery but were extremely high surgical risks. Cervical adenomas were present in 17 of 18 subjects; mediastinal adenoma in 1 of 18. Sixteen patients underwent selective parathyroid venous catheterization, which facilitated subsequent arteriographic localization. Selective arteriographic localization and attempted angiographic ablation were performed in all subjects with standard contrast, renografin-60. Laboratory studies, including serum calcium and PTH, were frequently performed before and after attempted angiographic parathyroid ablation. In all patients serum calcium fell to normal or subnormal levels within 48 h of attempted ablation. Prolonged follow-up (mean, 35.1 months) revealed that ablation was curative in 12 of 18 (sustained normocalcemia) and partially effective in 1 of 18 patients. For the entire group serum calcium fell from 3.14 +/- 0.07 at presentation to 2.42 +/- 0.07 mmol/L at the end of follow-up (or before surgery in unsuccessful cases; P less than 0.001). In 4 of 5 failed cases hypercalcemia recurred within 2 weeks. All 5 failed cases underwent curative surgery, aided by accurate localization achieved during angiographic procedure. Several transient complications and 1 case of permanent hypoparathyroidism were noted. We conclude that angiographic ablation of cervical parathyroid adenomas can be considered as an extension of diagnostic angiographic procedures in selected cases of primary hyperparathyroidism who have failed prior surgery of possibly in rare cases where surgery is contraindicated.

Remote biomedical spectroscopic imaging of human artery wall.

We discuss a general technique, laser spectroscopic imaging (LSI), remote acquisition of spectroscopic images of biological tissues and tissue conditions. The technique employs laser-induced spectroscopic signals, collected and transmitted via an array of optical fibers, to produce discrete pixels of information from which a map or image of a desired tissue characteristic is constructed. We describe a prototype LSI catheter that produces spectral images of the interior of human arteries for diagnosis of atherosclerosis. The diagnostic is based on the fact that normal artery wall and atherosclerotic plaque exhibit distinct fluorescence spectra in the 500-650 nm range when excited by 476-nm laser light; the fluorescence from blood is minimal. The catheter is composed of 19 optical fibers enclosed in a transparent, protective shield. Argon ion laser radiation is used for excitation, and an optical multichannel spectral analyzer is used for detection. Sequential sampling is used to minimize crosstalk among fibers and reduce blurring of the image. Computer-processed 19-pixel spectroscopic images are produced of fresh cadaver artery in vitro. Regions of normal tissue, plaque, and blood are identified, and the diagnoses are confirmed histologically and by direct spatial correlation. The results demonstrate the concept of using this laser catheter system for real-time imaging.

Pancreatic masses that angiographically simulate intrasplenic lesions.

Major improvements in the resolving power of computed tomography and ultrasound over the last decade have greatly improved the preoperative evaluation of abdominal masses. Angiography is, however, still often required for vascular mapping and assistance in the differential diagnosis. Although the site of origin of an avascular, intrasplenic mass may be the spleen, our experience and review of the literature indicates that such primary or secondary splenic masses are relatively rare. A primary pancreatic mass often a pseudocyst is a more frequent cause and should figure prominently in the differential diagnosis.

A comparison of Hexabrix and Renografin 60 in peripheral arteriography.

Fifty-one patients were analyzed after a randomized double-blind study comparing Hexabrix and Renografin 60 in peripheral arteriography. The arteriographic studies and the volumes of contrast material used in both groups were similar. Hexabrix caused significantly less pain and discomfort than Renografin 60, and the diagnostic quality of the radiographs was comparable. A slightly higher incidence of minor side effects was noted in the Hexabrix group, mostly nausea and vomiting and urinary retention.

Catheter hysterosalpingography.

The authors describe a 5-F catheter which is simpler to use than the standard vacuum cannula when performing hysterosalpingography.

A nonoperative technique for establishment of a gastrostomy in the dog.

Gastrostomies have been performed nonoperatively under local anaesthesia using a simultaneous percutaneous and endoscopic approach. This technique has been modified to be done under fluoroscopy without the need for endoscopy. The technique and results in five dogs are described.

A comparison of hexabrix and Renografin 60 in peripheral arteriography.

Fifty-one patients were analyzed after a randomized double-blind study comparing Hexabrix and Renografin 60 in peripheral arteriography. The arteriographic studies and the volumes of contrast material used in both groups were similar. Hexabrix caused significantly less pain and discomfort than Renografin 60, and the diagnostic quality of the radiographs was comparable. A slightly higher incidence of minor side effects was noted in the Hexabrix group, mostly nausea and vomiting and urinary retention.

The cervical split: a pseudofracture.

A horizontal lucent line projecting over a cervical vertebral body on lateral radiographs and simulating a fracture is described. The pseudofracture line results from the lucency between contiguous proliferative osteophytes at the uncinate process/vertebral articulation. Associated disc space narrowing was seen in all of our eleven cases. The origin of this pseudofracture line, cases illustrating this phenomenon, and additional projections helpful for clarification are presented.