Assessment of peripheral vascular disease in patients with diabetes. Two case studies.

This report proposes that perfusion scanning in combination with arteriography be included in the diagnostic work-up of the diabetic patient who, because of peripheral vascular complications, is a candidate for surgery. Two cases are reported which illustrate the extremes of the findings: abnormal arteriogram-normal scan indicating large-vessel disease without significant small-vessel involvement. It is suggested that these patients are candidates for vascular reconstruction. The other extreme is the normal arteriogram-abnormal scan indicating small-vessels disease without significant large-vessel involvement. It is apparent that these patients are not candidates for vascular reconstruction.

Food cobalamin malabsorption occurs frequently in patients with unexplained low serum cobalamin levels.

Malabsorption of food-bound or protein-bound cobalamin with normal absorption of free cobalamin has been described in studies of patients with gastric dysfunction. We used the egg-yolk cobalamin absorption test to study 47 patients selected not because of known gastric disorders but because they had low serum cobalamin levels with normal Schilling test results. Their egg test results were significantly lower than in normal controls, while Schilling test results were normal. Twenty of the subjects had egg test excretion below 1.5%. No features distinguished them from the 27 who excreted more than 1.5% other than the presence of lower pepsinogen I:II ratios. Eight of 19 tested patients with food cobalamin malabsorption had no evidence of abnormal gastric status by blood tests and/or gastric analysis. Also noteworthy was the finding of food cobalamin malabsorption in 60% of tested patients who had neurologic, cerebral, or psychiatric abnormalities. Food cobalamin malabsorption appears to be associated frequently with otherwise unexplained low cobalamin levels. Low cobalamin levels in patients with normal Schilling test results cannot be dismissed as insignificant without also testing for food cobalamin malabsorption, whether or not the patients have known gastric dysfunction.

Unsuspected pernicious anemia in a patient with sickle cell disease receiving routine folate supplementation.

Although the issue of folate supplementation in sickle cell anemia remains controversial, routine supplementation has become common. The major drawback to indiscriminate folate therapy is the potential of masking findings of vitamin B12 (cobalamin) deficiency. This has been dismissed as a problem in sickle cell anemia because of the generally young age of the patients. However, because young blacks, especially women, are at higher risk for developing pernicious anemia than whites, sickle cell anemia and pernicious anemia can be expected to coexist occasionally. In this article we describe such a patient and recommend that routine folate supplementation should not be given in sickle cell anemia before determining the vitamin B12 status.

Radioiodine dosimetry in patients with end-stage renal disease receiving continuous ambulatory peritoneal dialysis therapy.

In patients with end-stage renal disease (ESRD), Na131I dosages for thyroid cancer may have to be reduced to avoid excess radiation doses to red marrow, because radioiodine is primarily excreted by kidneys. In ESRD patients receiving continuous ambulatory peritoneal dialysis (CAPD) therapy (three to five 2-L exchanges daily) creatinine clearance rates are very low (mean, 7 mL/min), and radioiodine clearance rates may be proportionately reduced. Thus, radioiodine kinetic studies were performed in two hypothyroid CAPD patients with thyroid cancer, in eight euthyroid CAPD patients, and in eight thyroid cancer patients with normal renal function. All received Na131I or Na123I orally, with serial blood, urine, and/or dialysate sampling for 24-70 h. Dosimetry calculations were performed using the MIRDOSE3 computer program. In CAPD patients, serum radioiodine half-times were 5 times longer, and radioiodine clearance rates by urine plus dialysate were 20% of those in patients with normal renal function. Na131I dosages for the two CAPD patients with thyroid cancer were reduced from 150 mCi [5.6 gigabecquerels (GBq)] to 26.6 mCi (0.98 GBq) and 29.9 mCi (1.11 GBq), respectively, resulting in radiation doses to red marrow and total body comparable to those in patients with normal renal function who received a mean of 148 mCi (5.5 GBq) Na131I. Thus, in patients receiving continuous ambulatory peritoneal dialysis therapy, 5-fold reductions in radioiodine clearance rates require 5-fold decreases in Na131I dosages to avoid excessive radiation doses to total body and red marrow.

A new objective criterion for determining, noninvasively, the healing potential of an ischemic ulcer.

Peripheral vascular perfusion studies using intravenously administered thallium-201 were performed on 13 patients suffering from ischemic ulcer of the lower extremities. Scintillation camera views and point counting over the lesion and adjacent region were utilized to define qualitatively and quantitatively the relative hyperemia of the lesion. The preliminary findings demonstrate that when the relative hyperemia was equal to or greater than 1.5, 100% (seven of seven) went on to heal their ulcer with conservative management. Of those without this degree of hyperemia, 83% (five of six) will require amputation. Based on this limited series, noninvasive assessment of the relative hyperemia of an ischemic ulcer using thallium-201 is a new, useful, and objective indicator of the healing potential of a so-called ischemic ulcer.

Imaging of medullary thyroid carcinoma and hyperfunctioning adrenal medulla using iodine-131 metaiodobenzylguanidine.

Scintigraphy with radiolabeled metaiodobenzylguanidine was performed in a patient with MEN Type IIa having a pheochromocytoma of the right adrenal gland, adrenomedullary hyperplasia of the left adrenal gland and a primary medullary thyroid carcinoma. The scintigraphic findings demonstrate visualization of all the above mentioned pathologies.

Accumulation of 99mTc-glucoheptonate in acutely infarcted myocardium.

The distribution of 99mTc-glucoheptonate in normal mice and its accumulation in acutely infarcted myocardium were studied in animals. Rapid blood clearance and low concentration of the tracer in normal myocardium were found in tissue distribution studies performed in mice. Experimental myocardial infarction was performed in nine dogs. Four hours after the intravenous injection of 99mTc-glucoheptonate the uptake ratio of the myocardial infarcted area to normal myocardium was 20:1; to blood, 9:1; and to lung, 6:1. The greatest concentration of radiopharmaceutical in the infarcted tissue was noted in areas that had 20-40% of normal perfusion. Regions of infarction were clearly defined by external gamma scintigraphy. Clinical investigation of this tracer in humans appears warranted.

Accumulation of 99mTc-diphosphonate in malignant pleural effusions: detection and verification.

Increased accumulation of radioactivity was observed in two cases of malignant pleural effusions during the performance of routine bone scans with 99mTc-diphosphonate. This previously unreported finding was verified both qualitatively and quantitatively by appropriate scanning and laboratory techniques.

A useful, objective criterion for determining the healing potential of an ischemic ulcer.

Peripheral vascular perfusion studies utilizing intra-arterial injections of radioactive microspheres were performed on 60 patients who had ischemic ulcers of the lower extremity. Point counting over the lesion and adjacent areas was utilized to qualitate and quantitate the relative hyperemia of the lesion. When this this relative hyperemia ulcers healed. In those without this degree of hyperemia only approximately 10% eventually had their ulcers healed without surgical intervention. Assessment of relative hyperemia of the ulcer bed is a useful, objective, prognostic indicator of the healing potential of an "ischemic" ulcer.

Osteosarcoma presenting as intestinal obstruction.

Osteosarcoma commonly presents with osseous and pulmonary metastases. We present an unusual case of extraosseous metastatic abdominal chondroblastic osteosarcoma presenting as intestinal obstruction.

Radioactive tracers in peripheral vascular disease.

The use of radioactive tracers in the diagnostic and therapeutic evaluation of the patient with peripheral arterial or venous disease has proven to be clinically useful. Their application has provided a means by which the regional distribution of perfusion at the level of the microcirculation, at rest and under various stresses, can be assessed. Graft patency can be determined simply and repeatedly, and the relative perfusion of "ischemic" ulcers can be used to assess their healing potential. The presence of arteriovenous shunts can be verified, localized, and quantified. Venous thrombi can be detected, and the competence of the venous valvular system and muscle pump as well as the hemodynamics of the venous system can be quantified.

Radiosynovectomy's clinical applications and cost effectiveness: a review.

It is apparent that from the work of the authors and many others, including the work of Rivard, Sledge, Zuckerman, among others, that radiosynovectomy has an important role to play in providing effective treatment of affected joints associated with rheumatoid arthritis and other forms of arthritis as well as the hemophiliac joint. The treatment offers relief from the effects of recurrent joint effusion with an approximately 60% to 66% favorable response and from recurrent hemarthrosis in the hemophiliac joint with an approximately 75% to 80% favorable response. The impact of providing radiosynovectomy as an alternative to surgical synovectomy is seen, where postoperative side effects such as joint stiffness are avoided, improved quality of life is repeatedly documented, and the cost savings in health care dollars, particularly evident in the hemophiliac joint in this relatively small population, are potentially enormous. With almost two million people in the United States suffering from rheumatoid arthritis, the potential savings in health care dollars is also enormous. As with any use of in vivo radiopharmaceuticals, the potential for radiation-induced damage exists. However, with a 25 plus year record of use, more optimally configured radiopharmaceuticals, and the addition of maneuvers to minimize potential joint leakage, the risk of radiation induced damage appears to be minimal. It appears as though radiosynovectomy is an effective as well as cost-effective alternative to surgical synovectomy and is becoming the procedure of choice particularly in the hemophiliac patient with recurrent hemarthrosis and synovitis who has failed medical therapy. It is also the procedure of choice in patients for whom surgery is contraindicated because of the presence of clotting factor inhibitors.

Perfusion of ischemic ulcers of the extremity: a prognostic indicator of healing.

Forty patients with an ischemic ulcer of the lower extremity had peripheral vascular perfusion studies, performed with intra-arterial injections of aggregated technetium Tc 99m serum albumin microspheres (15mu to 30mu in diameter), in an attempt to develop an objective prognostic criterion for healing. The association between ulcer healing and the presence or absence of diabetes mellitus, palpable peripheral pulses, and patent trifurcation vessels on the arteriogram was reviewed and no association was noted. When, however, there was a relative hyperemia of the ulcer bed in comparison to the adjacent tissue of at least 3.5:1, as determined by counting the amount of radioactivity per unit area, 86% of patients went on to heal their ulcers. In those without this degree of hyperemia, only 11% were healed with conservative nonsurgical management. The results have shown that relative hyperemia of the ulcer bed is a clinically useful prognostic indicator in the patient with ischemic ulcer disease.

Inconsistent effects of the proline12 --> alanine variant of the peroxisome proliferator-activated receptor-gamma2 gene on body mass index in children and adolescent girls.

OBJECTIVE: To ascertain whether variation in peroxisome proliferator-activated receptor-gamma (PPAR-gamma), a nuclear ligand-dependent transcription factor affecting both adipocyte differentiation and insulin sensitivity, influences body mass index (BMI). DESIGN: Association study. SETTING: Academic research environment. PATIENT(S): Children with premature pubic hair and adolescent girls with hyperandrogenism. INTERVENTION(S): Assay for P12A and P115Q variants and measure BMI. MAIN OUTCOME MEASURE(S): BMI and PPAR-gamma genotypes. RESULT(S): Fourteen subjects were heterozygous for P12A; two were homozygous. None carried the P115Q allele. No significant differences in BMI or basal androstenedione concentrations between P12 carriers and noncarriers were found. Thirty-nine subjects had BMI values at two time points; mean BMI was significantly greater in the P12A carriers at time point 2. Those P12A carriers obese at time point 1 became more obese; lean mutation carriers tended to remain lean. Annual rate of increase in BMI was significantly greater in the P12A carriers than the noncarriers. CONCLUSION(S): Our findings suggest that P12A may be a genetic marker indicating risk for obesity persisting into adolescence. Future studies are needed to determine whether the divergent effects of P12A persist into adulthood, to elucidate the mechanism of this effect, and to replicate our findings in other populations.

Gated intracoronary thallium201 scintigraphy: feasibility and potential clinical advantages.

Visualization of ventricular walls with true global motion and myocardial thickening is not possible with use of present scintigraphic techniques. When thallium 201 (201TI) is injected intravenously (IV), only about 5% reaches the myocardium. However, if 201TI is injected intracoronarily, 100% reaches, and approximately 88% localizes in, the myocardium, which results in higher count rates than when given IV, permitting acceptable acquisition times for gated true wall motion studies. The authors describe a new technique using intracoronary (IC) 201TI to acquire high count rate, high contrast, and short acquisition time in gated true wall motion studies. Thirteen patients were studied at rest with gated IC thallium. Six of these patients also had resting IV 201TI myocardial studies. After routine coronary angiography, 0.75 mCi of 201TI was injected into each coronary artery. Multiple sequential one-minute gated studies were obtained in LAO and RAO projections, followed by sequential five-minute images for two hours to determine 201TI redistribution kinetics. Regions of interest over segments of left and right ventricles and background permitted definition of temporal and spatial distributions. Three one-minute gated studies were summed with a total count of 2,100 K for a three-minute acquisition. Myocardium-to-background ratios were as high as 13:1 with a mean of 11.4:1 in the IC study compared with 2.3:1 in the IV studies. Washout half-time in normal myocardium was 95 +/- 5 min. The detectability and size of perfusion defects were different on gated diastolic and systolic, nongated, and IV studies. Questionable defects seen on nongated studies or after IV administration were easily noted on gated diastolic images.(ABSTRACT TRUNCATED AT 250 WORDS)

Aortic ejection fraction: a new hemodynamic parameter and its relationship to aortic insufficiency.

Pulsations of the ascending aorta during fluoroscopy in patients with aortic insufficiency (AI) have been described. The authors present their observations of a similar phenomenon in patients who have AI undergoing scintiangiography. In addition, this paper describes a technique to validate and quantitate this finding. They studied 17 patients with documented AI and 14 subjects of a control group. First-pass studies were acquired in the RAO 15 degrees projection. Regions of interest were placed over the proximal aorta during systole and diastole. An aortic ejection fraction (AF) was determined. The calculated AEF data were correlated with the presence or absence of AI. The mean AEF from the 17 AI patients was 27.1 +/- 7.2%, while the mean for the non-AI group was 12.0 +/- 6.5% with p less than .001. An AEF of 18% separates the two groups with a sensitivity, specificity, and accuracy of 88%, 86%, and 87% respectively. Preliminary data demonstrate a mean reduction in AEF of 12.2 percentage points in 7 AI patients who underwent aortic valve replacement. The AEF may be a useful new parameter to evaluate hemodynamic changes associated with aortic valve replacement in patients with aortic insufficiency.

Circumferential quantitative analysis of planar 201T1 myocardial scintigraphy in the diagnosis of coronary artery disease.

Methodology for the computer analysis of 201T1 myocardial perfusion images has been developed by several laboratories. Substantial evidence of the advantage of this approach over visual inspection alone has been reported. The currently available computer analyses use different algorithms to analyze 201T1 kinetics in the myocardium. The authors evaluated and compared two widely used software programs, Medical Data System (MDS): a mean-count profile, and the Cedars Sinai (CS): a maximal-count profile, of planar 201T1 scintigraphy for their ability to detect coronary artery disease (CAD).

Thallium 201 exercise scintigraphy for detection of multivessel coronary artery disease after transmural myocardial infarction.

Fifty patients with prior transmural myocardial infarction were studied with cardiac catheterization, coronary angiography, and thallium 201 exercise perfusion scintigraphy.Obstructive coronary disease involved two or three vessels in 37 patients. The sensitivity of a positive electrocardiographic test during exercise for detecting multivessel coronary disease was only 40 percent (15/37), and the sensitivity of a reversible defect on (201)Tl perfusion scintigraphy was 48 percent (18/37). The combination of exercise testing and (201)Tl scintigraphy detected multivessel coronary disease in 75 percent (28/37) (P < .05).New perfusion defects occurred in 61 percent (13/21) of patients with inferior myocardial infarction and multivessel coronary disease whereas it occurred in only 35 percent (5/14) of patients with prior anterior infarction and multivessel coronary disease (P < .05).(201)Tl exercise perfusion scintigraphy appears to be more sensitive for detecting significant multivessel coronary disease in the presence of previous inferior infarction compared with previous anterior infarction.Combined graded exercise testing and (201)Tl perfusion scintigraphy can reliably detect the presence of significant multivessel coronary disease after transmural myocardial infarction.

Detection of myocardial sarcoidosis by thallium 201 imaging.

Thallium 201 myocardial perfusion scanning revealed focal left ventricular defects at rest in four of 30 patients (13 percent) with systemic sarcoidosis. All the defects decreased in size during thallium stress imaging, a finding opposite of that usually seen in myocardial ischemia. Nine patients had abnormal right ventricular visualization at rest. Thus, 11 of 30 (37 percent) had abnormal resting myocardial scand. Two of the four patients with left ventricular defects were studied serially for up to 1.5 years to evaluate response to corticosteroid therapy. The myocardial defect diminished in one patient, whereas the second patient, maintained for 2 years on low doses of steroids, had no resolution. In patients suspected of focal myocardial involvement by sarcoidosis on thallium scanning dynamic changes in scan defects can occur during exercise which are the reverse of those usually seen in coronary artery disease. These defects probably represent myocardial sarcoid. Right ventricular uptake generally appears to correlate with the severity of pulmonary involvement by sarcoidosis, yet does not appear to be a specific finding.

B-cell immunoblastic sarcoma as a cause of a photopenic lesion on bone scintigraphy: an initial description.

Photopenic metastatic lesions on bone scintigraphy have been previously reported. However, this finding is not emphasized for B-cell immunoblastic sarcoma. We report a case of B-cell immunoblastic sarcoma, which presented as an aggressive pancoast tumor with extensive rib destruction. Bone scintigraphy findings demonstrated a photopenic lesion with high gallium avidity. Correlative chest radiograph and CT scan are described.