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D H Porter

Publications and source records attributed to D H Porter.

At least 19 recordsLinked to original sources
PubMed1992

Image-directed percutaneous biopsy. A comparison of cytologic and histologic findings.

BACKGROUND: Image-directed biopsies may be collected as histologic or cytologic specimens. METHODS: In 34 patients, the results of aspiration cytologic examination were compared prospectively with core tissue biopsy findings obtained and diagnosed independently using the same image-guided procedure. RESULTS: Cytologic examination disclosed 22 patients with positive or suspicious findings of malignancy; there was one false-suspicious result. Seventeen patients with such results were discovered by examining the core biopsy specimens. Cytologic findings also were more definitive in diagnosing malignancy. Those in whom an immediate interpretation could be done were more likely to have adequate cytologic specimens (88%) than those without (62%). One to five passes were done, but all 21 patients with definitive findings of either benign or malignant by cytologic examination underwent three or fewer passes. The three patients with positive biopsy results, but less definitive cytologic findings, all underwent only one cytologic pass. CONCLUSIONS: Therefore, it was concluded that cytologic examination is more sensitive and definitive than biopsy in diagnosing lesions using image guidance. Immediate interpretation and/or multiple passes increase the diagnostic yield. However, more than three aspiration cytologic passes appear to yield diminishing returns.

Biopsy, Needle↗
PubMed1992

Role of superficial femoral artery puncture in the development of pseudoaneurysm and arteriovenous fistula complicating percutaneous transfemoral cardiac catheterization.

Of 13,203 transfemoral diagnostic and therapeutic cardiac catheterization procedures performed between January 1, 1980 and December 31, 1990, 73 (0.55%) were complicated by pseudoaneurysm (PA) formation, and 15 (0.11%) by arteriovenous fistulas (AVF). The rate of PA increased progressively from 0.44% (1980-1987), to 0.59% (1987-1989), to 0.92% (1990), with no corresponding change in the incidence of AVF. The rising incidence of PA complicating transfemoral cardiac catheterization was associated closely with the use of larger diameter catheters and aggressive antiocoagulation during coronary interventions, but findings during surgical repair suggested that puncture of the superficial femoral (SFA), rather than the common femoral artery (CFA), was an important avoidable cause of some PA and AVF. A technique for fluoroscopic localization of the puncture site to avoid inadvertent SFA puncture and the associated increased risk of complication is proposed.

Aneurysm↗
PubMed1992

Peripheral directional atherectomy: 4-year experience.

Directional atherectomy alone or with supplemental percutaneous transluminal angioplasty was used to treat peripheral vascular lesions in 77 patients (85 procedures). Lesions involved 17 iliac arteries, 45 infrainguinal arteries, and 23 laser extremity vein bypass grafts. Technical success, defined as reduction of stenosis diameter to 30% or less of the normal vessel diameter, was achieved in 78 of 85 (92%) cases. The complication rate was 21% (18 of 85 procedures). Most complications were minor and were related to puncture sites. Patients underwent noninvasive follow-up studies, including measurement of ankle-brachial index and segmental pressures, plethysmography, and clinical examination. The mean follow-up period was 13.5 months. The probability of 1-, 2-, and 3-year patency for lesions treated with atherectomy alone was 92%, 84%, and 84%, respectively. Kaplan-Meier survival analysis revealed no difference in 2- to 3-year patency rate on the basis of lesion location or presence of calcification, eccentricity, or ulceration. Diabetic patients, however, had a higher restenosis rate than did patients who were not diabetic (P less than .03).

Aged↗
PubMed1992

The Simon nitinol filter: evaluation by MR and ultrasound.

In this prospective blinded study of inferior vena caval (IVC) patency, 18 patients underwent 25 duplex ultrasound (US) and magnetic resonance (MR) angiography examinations over an eight-month period following Simon nitinol filter placement. Clinical examination for lower extremity venous stasis and plain abdominal radiography were also performed. Twenty-three of 24 MR examinations and 11 of 24 US examinations were judged technically adequate by the blinded observers. One technically adequate US exam was false positive for intraluminal caval thrombus. Thirteen technically inadequate US examinations missed 3 complete caval occlusions and 2 partial occlusions. MR identified all patients with complete or partial caval occlusion. The authors conclude that duplex US reliably confirms IVC patency only when strict criteria for technical adequacy and interpretation are met (good visualization of filter and IVC above and below filter). MR, although expensive, more reliably identifies nonoccluding intraluminal thrombus and caval occlusion. It should be the noninvasive study of choice in symptomatic patients with venous stasis and patients with recurrent pulmonary emboli.

Adult↗
PubMed1991

Renal artery imaging: a prospective comparison of intra-arterial digital subtraction angiography with conventional angiography.

This study describes a systematic comparison of intra-arterial digital subtraction angiography (DSA) of the main renal arteries with conventional angiography (CA), the currently accepted "gold standard" for the diagnosis of renal artery stenosis. Twenty-five patients scheduled for abdominal aortography for various indications underwent first DSA then CA. The DSA and CA images were evaluated for number of renal arteries, presence and grade of renal artery stenosis, presence of post-stenotic dilation or fibromuscular changes, and diagnostic and pictorial adequacy of the images. DSA was found to be diagnostically adequate in 92% of cases, compared with 96% for CA. In evaluating significant main renal artery stenosis, which the authors assumed to be any stenosis greater than 50%, there were 10 such stenoses seen by CA. DSA also detected 10 cases, but there was 1 false positive and 1 false negative, yielding a sensitivity of 90% and a specificity of 98%. There was also close correlation of DSA and CA for the few cases of post-stenotic dilatation and fibromuscular dysplasia encountered. The authors conclude that DSA is an acceptable substitute for CA in the evaluation of patients for main renal artery stenosis.

Angiography↗
PubMed1991

Magnetic resonance imaging: a reliable test for the evaluation of proximal atherosclerotic renal arterial stenosis.

Symptomatic renal artery stenosis is a significant and treatable clinical problem. A reliable and accurate noninvasive method of screening for renal artery stenosis has not yet been found. We used magnetic resonance imaging to study 37 patients who had undergone recent renal angiography. Fourteen patients had normal renal arteries by angiography. In 23 patients either unilateral or bilateral stenosis or occlusion was present. The disease process in all patients appeared to be atherosclerosis. The average age of the 37 patients was 68 years. The magnetic resonance scans and angiograms were read independently by two different radiologists, each of whom was blinded to the clinical history and the results of the other study. Renal arterial stenoses found on angiogram and magnetic resonance scans were graded as absent (0% to 24%), mild (25% to 49%), moderate (50% to 74%), or severe (75% to 99%). The magnetic resonance imaging results concurred with the angiographic findings in 70 of 77 arteries (91%). Magnetic resonance imaging predicted the presence of a greater than 50% stenosis of the renal artery with a sensitivity of 100% and a specificity of 94%. Magnetic resonance imaging may prove to be the best noninvasive screening test for proximal atherosclerotic renal arterial stenosis.

Adult↗
PubMed1990

Abdominal aorta and renal artery stenosis: evaluation with MR angiography.

A blinded, prospective study with magnetic resonance (MR) angiography was performed to study patients who had undergone abdominal aortography. In 55 renal arteries among 25 patients, MR angiography had a sensitivity of 100% for detecting renal artery stenosis of 50% or greater and a specificity of 92%. With MR angiography, the degree of renal artery stenosis was overgraded in four of 55 renal arteries: Mild stenosis was overgraded as moderate stenosis in two arteries and as a severe stenosis in one, and a moderate stenosis was overgraded as a severe stenosis in one. The number of renal arteries was correctly determined in all cases. The renal arteries could be well evaluated only in the proximal third of the vessel, precluding detection of more distal stenoses. Atherosclerotic plaque uniformly appeared dark on gradient-echo images and was easily differentiated from bright, flowing blood in the aortic lumen. MR angiography enabled correct grading of the presence of atherosclerotic plaque and stenoses of the abdominal aorta in 22 of 25 patients (88%). The authors conclude that MR angiography has the potential to be a useful screening technique for patients with suspected renal artery stenosis and disorders of the abdominal aorta, but further clinical studies are warranted.

Angiography↗
PubMed1990

Simultaneous occurrence of superficial and deep thrombophlebitis in the lower extremity.

Forty-two consecutive patients diagnosed with superficial phlebitis were seen during a 5-year period. Thirty-five of the 42 patients were outpatients. The diagnosis of superficial phlebitis was made by the presence of palpable subcutaneous cords in the course of the greater saphenous vein or its tributaries in association with tenderness, erythema, and edema. The presence of concurrent deep venous thrombosis (DVT) was assessed by impedance plethysmography in 37 patients, compression venous ultrasonography in 3 patients, and venography in 8 patients. Five of the 42 patients (12%) had DVT. Four of these five patients had a positive impedance plethysmographic or ultrasonographic test result followed by a confirmatory venogram. The fifth patient had a positive ultrasonographic test result, but no venogram was performed. Two of the five patients had clots that involved the popliteal or femoral veins. Four of 23 patients (17%) with superficial phlebitis at or above the knee had DVT. Only 1 of the 19 patients (5%) with superficial phlebitis below the knee had DVT. Three of the five patients with both superficial phlebitis and DVT had undergone surgery recently. All but 3 of the 42 patients (93%) had varicose veins. No patients had clinically apparent pulmonary emboli. DVT occurred in 17% of the patients with above-knee extension of the superficial phlebitis. In the clinical management of superficial lower-limb thrombophlebitis, noninvasive tests should be performed to guide therapy. When superficial phlebitis develops after recent surgery or the superficial phlebitis extends above the knee, diagnostic surveillance should be especially strict. When the noninvasive test results are equivocal, phlebography is indicated to rule out DVT.

Female↗
PubMed1989

Simon nitinol inferior vena cava filter: initial clinical experience. Work in progress.

The Simon nitinol filter for percutaneous interruption of the vena cava to prevent pulmonary embolism is currently undergoing a multicenter clinical trial. Preliminary clinical results are reported as work in progress. The results in 44 patients at two centers are analyzed in detail, and major events are reported from 103 patients in 17 centers in the United States during a 10-month period. The filter was successfully inserted via the femoral or jugular route in all patients through a 9-F catheter. The placement procedure was easy and without significant complications. Follow-up studies included plain radiography, ultrasonography, magnetic resonance (MR) imaging, and clinical evaluation. No filter migration or perforation occurred among the 103 patients. Symptomatic occlusions occurred in 7%-9%, comparable to other series, and some asymptomatic occlusions were detected with MR imaging only. The implications of occlusion of the filter are discussed.

Adult↗
PubMed1988

Cholecystojejunostomy intussusception.

Intermittent prolapse of a jejunal loop into the gallbladder lumen was observed following cholecystojejunostomy in a patient with advanced carcinoma of the pancreas. This unusual complication was documented by cholangiography and sonography.

Aged↗