Cyclic seasonal variation in plasma lipid and lipoprotein levels: the Lipid Research Clinics Coronary Primary Prevention Trial Placebo Group.

Seasonal plasma lipid and lipoprotein cycles were studied in 1446 hypercholesterolemic 35-59 year-old men followed for 7 years as the placebo group of the Lipid Research Clinics (LRC) Coronary Primary Prevention Trial (CPPT). Separate periodic time series were calculated for each study participant; mean parameter estimates were obtained by vector algebra. Highly significant (p less than 0.001) synchronous sinusoidal seasonal cycles, peaking in the first month of winter, were demonstrated for plasma levels of total (TOT-C), low-density lipoprotein (LDL-C), and high-density lipoprotein (HDL-C) cholesterol. Their mean seasonal changes (nadir to zenith) were 7.4, 6.4, and 0.8 mg/dl, respectively. An irregular but statistically significant seasonal pattern was also observed for plasma triglyceride (TG) levels, with peak levels in the autumn. The variation of these seasonal effects among subgroups and geographic locales and their correlation with seasonal weight and dietary patterns yielded few clues as to their underlying etiologic mechanisms.

Contrast-enhanced peripheral MR angiography from the abdominal aorta to the pedal arteries: combined dynamic two-dimensional and bolus-chase three-dimensional acquisitions.

UNLABELLED: Wang Y, Winchester PA, Khilnani NM, et al. Contrast-enhanced peripheral MR angiography from the abdominal aorta to the pedal arteries: Combined dynamic two-dimensional and bolus-chase three-dimensional acquisitions. Invest Radiol 2001;36:170-177. RATIONALE AND OBJECTIVES: To obtain reliable contrast-enhanced peripheral MR angiography for imaging peripheral vascular disease from the abdominal aorta to the pedal arteries. METHODS: A protocol consisting of contrast-enhanced, dynamic two-dimensional (2D) acquisition at the feet and calf and bolus-chase three-dimensional (3D) acquisition from the abdominal aorta to the calf was developed and applied in patients with peripheral vascular disease. The performance of this integrated protocol was assessed in 89 consecutive patients. RESULTS: The bolus-chase 3D acquisition was of diagnostic quality in 100% of the acquisitions in the abdomen, 96% in the thigh, and 43% in the calf. The poor quality of the calf acquisitions was due to insufficient spatial resolution, poor arterial signal, and venous contamination. Diagnostic-quality images were obtained in 100% of the dynamic 2D acquisitions of the calf and 98% of the feet. CONCLUSIONS: The combined dynamic 2D and bolus-chase 3D contrast-enhanced MR angiography technique provides diagnostic images of the entire lower extremity.

Quantification of visual fields for statistical analysis.

The importance of visual fields in the study of ocular vascular disorders prompted the development of a method to convert visual fields plotted on a Goldmann perimeter into a digital form so that the data could be analyzed and stored by a computer. An instrument called a scotometer was designed to measure the visual fields and the various scotomata, and a data coding form was developed to facilitate the entry of the data into the computer. After extensive testing, this method is now being used in several clinical trials. Statistics have been computed that support the reliability of the coding process.

Ostial renal artery stent placement in patients 75 years of age or older.

Renal artery stent placement has been shown to improve blood pressure (BP) and stabilize renal function in patients with atherosclerotic renovascular disease. However, limited data are available in patients > or = 75 years of age. We analyzed the prestent characteristics and clinical outcomes of patients aged > or = 75 years who underwent renal artery stenting at our institution. We compared these data with those from the remainder of our stent cohort. Nineteen of 89 (21.3%) stent patients were > or = 75 years old. Before intervention, those > or = 75 years were significantly more likely to be women (84.2% v 55%; P = .02), current or former smokers (78.6% v 36.8%; P = .002), and on a greater number of antihypertensive medications (3.68 v 2.80; P = .048). Average clinical follow-up was similar in both groups (23.9 v 23.2 months; P > .05). At last available follow-up, there were more deaths in those > or = 75 years (7/19 v 5/70; P = .038). No significant difference was found in the incidence of dialysis after intervention (3/19 v 7/70). Seventy-four percent of those > or = 75 years had improved BP, 21% were stable, and 5% were worse. Renal function was improved in 26%, stable in 53%, and worse in 21%. Among those > or = 75 years, there was a significant decrease in systolic BP (186.9 to 144.4; P < .01). There was a trend toward decreased diastolic BP and medications. These clinical results did not differ significantly from patients <75 years. Patients > or = 75 years of age with atherosclerotic renovascular disease have a higher incidence of mortality 2 years after renal artery stent placement, but they seem to derive clinical benefit comparable to younger patients.

Prevention of recurrent pulmonary edema in patients with bilateral renovascular disease through renal artery stent placement.

Pulmonary edema and congestive heart failure (both referred to here as PE) have been reported to be complications of bilateral renal artery stenosis or unilateral stenosis in a solitary functioning kidney (both referred to as BRAS). The goals of this study were to determine whether a history of PE was more common in patients with BRAS than in those with unilateral stenosis and a normal contralateral kidney (URAS), and whether recurrent PE could be prevented by renal artery stent placement. We evaluated 90 consecutive patients with renovascular disease who were treated with percutaneous renal artery stent placement. History and clinical follow-up were obtained through chart review and phone contact with referring physicians. Mean follow-up was 18.4 months after stent placement. Twenty-three of 56 (41%) subjects with BRAS had a history of PE before revascularization, compared with four of 34 (12%) subjects with URAS (P = .05). Twenty-five of the 27 patients with history of PE had adequate clinical follow-up. Seventeen of the 22 (77%) subjects with BRAS and history of PE had no further PE after stent placement in one or both renal arteries. The five BRAS subjects with recurrent PE after stent placement had evidence of stent thrombosis or restenosis. In contrast, only one of three (33%) URAS subjects with a history of PE remained free of PE after stent placement. We conclude that PE is a common complication of BRAS, but not of URAS. In patients with BRAS, recurrent PE can be prevented by successful stent placement in one or both renal arteries.

13CO2 isotopic laser used through the operating channel of laser laparoscopes: a comparative study of power and energy density losses.

OBJECTIVE: To evaluate the power transmission, spot size, power density, and energy density of a new isotopic carbon dioxide (13CO2) laser compared with a conventional CO2 laser. METHODS: Experiments were performed in a laboratory using a conventional CO2 laser and an isotopic 13CO2 laser. Two laparoscopes with 5-mm and 7.5-mm operating channels were connected to a standard coupler and to each of the lasers. Standardized measurements were made of power transmission and spot size using both nitrogen purge gas and CO2 purge gas at rates of 1-20 L/minute. Power density and energy density were calculated for continuous mode and ultrapulse mode transmission, respectively. RESULTS: The isotopic 13CO2 laser power transmission was higher and proportional to input power, while spot size was smaller compared with the conventional laser and was insensitive to power level or purge rate. Power density and energy density were markedly higher with the isotopic 13CO2 laser, reaching the threshold for complete ablation, and were much more predictable. The 7.5-mm operating channel generally had superior operating results compared with the 5-mm channel because of the smaller spot size and higher power transmission. CONCLUSIONS: The isotopic 13CO2 laser is associated with much higher power density and energy density capabilities than are conventional CO2 lasers. At surgery, we have noted less thermal injury, faster ablation, more precise and predictable tissue effects, and greater control of tissue effect with the isotopic 13CO2 laser than with other CO2 lasers. These results are attributed to the improved beam propagation through CO2 insufflation gas measured in the laboratory. Thermal injury can be varied according to the required surgical situation and can be kept to an absolute minimum at high-pulse energy.

Delayed epistaxis resulting from external carotid artery injury requiring embolization: a rare complication of transsphenoidal surgery: case report.

OBJECTIVE AND IMPORTANCE: Delayed epistaxis resulting from trauma to branches of the external carotid artery is an infrequent but potentially serious complication of transsphenoidal surgery. We report two cases of severe, delayed epistaxis in patients who had undergone transsphenoidal surgery. In both cases, noninvasive treatment failed, necessitating endovascular intervention. CLINICAL PRESENTATION: The first patient, a 52-year-old woman with a prolactinoma, underwent a second transsphenoidal resection 18 months after the first surgery. She was readmitted on postoperative Day 15 with massive epistaxis. The second patient, a 40-year-old woman, had undergone two transsphenoidal surgeries, 14 years apart, for an adrenocorticotropic hormone-secreting adenoma. She was readmitted with massive epistaxis on postoperative Day 17. INTERVENTION: Both patients were initially treated with nasal balloon packing but experienced recurrent hemorrhage when the balloon was deflated, necessitating referral to the interventional radiology department for embolization. At arteriography, the first patient was found to have a pseudoaneurysm of the medial branch of the left internal maxillary artery, which was subsequently embolized. Arteriography in the second patient revealed an abnormally dilated midline branch of the right internal maxillary artery in the nasal septum; this vessel was occluded at arteriography. CONCLUSION: Delayed massive epistaxis is a rare but significant complication of transsphenoidal surgery. Injury to branches of the external carotid artery, along with injury to the internal carotid artery, should be suspected in patients who present with delayed epistaxis after transsphenoidal surgery. Angiography performed in patients with refractory bleeding should include selective external carotid injections. Epistaxis that is refractory to anterior and posterior nasal packing may be effectively treated with endovascular embolization.

Is Hughes-Stovin syndrome Behçet's disease?

Hughes-Stovin syndrome (HSS) is a rare clinical disorder, which has been described as the presence of pulmonary artery aneurysm in the setting of systemic thrombosis. The term "Incomplete Behçet's Disease" has also been used to describe this syndrome due to the clinical and histopathological similarities between Behçet's disease and HSS. Indeed, pulmonary involvement can be indistinguishable between these two conditions of unknown pathophysiology. We describe an HSS patient who presented with a recurrent pulmonary artery aneurysm, review the clinical and pathological manifestations of HSS, discuss its similarities to Behçet's disease, and finally make the argument that HSS is in fact Behçet's disease.

In vitro model to evaluate the relative efficacy of catheter-directed thrombolytic strategies.

RATIONALE AND OBJECTIVES: Catheter-directed thrombolytic therapy has become an accepted treatment for many vascular occlusions. However, the relative rates of lysis of the different methods of drug administration have not been quantified. We developed an in vitro model to simulate and quantify local lytic therapy of a thrombotic vascular occlusion and tested it by evaluating three catheter-directed lytic strategies. METHODS: Seven-centimeter-long segments of 125I-fibrinogen-labeled thrombus made from recently expired human blood from a blood bank were formed in plastic tubes and were placed in a flowing stream of saline. Using multisidehole catheters, the clots were "treated" with intrathrombic saline or urokinase administered by drip infusion or forced injection using identical total doses of drug and volumes of fluid. Using endhole catheters, saline or urokinase was drip infused into the leading edge of the thrombus using the same protocol. A collimated scintillation detector was used to quantify the amount of activity remaining in the thrombus during each experiment, and the resultant time-activity curves for the different trials were compared. RESULTS: Forced-injection administration of urokinase using a multisidehole catheter produced the fastest lysis, resulting in a half-life of 42 min. The other infusion methods were slower, with half-lives of 153 min for multisidehole urokinase drip infusion, 365 min for endhole urokinase drip infusion, and more than 1,000 min for multisidehole catheter forced injection of saline and multisidehole and endhole saline drip infusion. The differences among these groups were reproducible and statistically significant. CONCLUSION: Results suggest that a simple and inexpensive in vitro model simulating lysis of a vascular occlusion can produce reproducible quantitative data. The data demonstrate that forced injection of lytic agents with a multisidehole catheter enhances the rate of thrombolysis and that the enhancement is not primarily attributable to the mechanical effect of this mode of administration.

Retained nephrostomy thread providing a nidus for atypical renal calcification.

Percutaneous nephrostomy (PCN) is a commonly performed procedure. The indications have expanded from merely providing emergency decompression of obstruction to being the initial step of many interventional procedures including percutaneous nephrolithotomy, ureteral stenting dilation and biopsy. Nephrostomy tube design has evolved from a simple trocar to the current self-retaining loop catheters. These catheters contain a suture which, when secured, locks the loop of the catheter in order to prevent accidental removal of the catheter. We present a case where incomplete removal of the locking suture providing the nidus for calcification within the renal pelvis.

The relationship of histologic and clinical factors in laryngeal papillomatosis.

Laryngeal papillomatosis is a disease that can lead to many surgical procedures, especially in children, and is potentially lethal. In this study, we reviewed 83 cases that yielded 902 separate laryngoscopy specimens to determine if any clinical or histologic findings were prognostic. "Juvenile" (n = 73) and "adult" (n = 10) cases were classified according to the number of separate lesions and the number of recurrences, but not necessarily according to age. Four prognostic indicators were constructed for the juvenile group and were analyzed by linear regression. Three new microscopic classifications were used: papillary, acanthomatous, and angiokeratotic. In juvenile cases, the last two categories appeared to be somewhat prognostic, along with several other factors. Some histopathologic findings contradicted classic descriptions. Differences in clinical manifestation and similarities in histopathology may suggest differential responses to the same causal agent.

Determinants of foster care placement for the maltreated child.

This study examined the records of the North Carolina Central Registry of Child Abuse and Neglect to determine which social, family, and child characteristics were most influential in the decision to place a child in foster care. These records contained all theoretically relevant factors as well as demographic data. Analysis included the computation of odds ratios for foster care for each of 250 variables. A maximum likelihood logistic regression model was constructed to obtain the independent and cumulative contribution of each factor. Some expected variables such as parental stress factors (substance abuse) and types of abuse (burns and scalds) placed a child at a significant risk for placement in foster care (p less than 0.01). However, less obvious factors such as referral source (law enforcement agencies) or geographic area also placed children at risk. Overall, the model explained little of the variance of these decisions (R2 = 0.168) and poorly predicted placement (sensitivity 66.3 per cent, specificity 74.6 per cent). Using existing data, we were unable to adequately describe the decision process in selecting foster care.

Renal vascular disease as a cause of hypertension.

In spite of our comprehensive understanding of renovascular hypertension, diagnostic tests based on the pathophysiology of the disease have been disappointing in their sensitivity and specificity. They are particularly unreliable in the setting of bilateral disease and renal dysfunction. The recent results of vascular surgery and renal angioplasty combined with the use of metallic stents have shown dramatic benefits in revascularization even in the setting of renal artery occlusion, ostial renal artery stenosis, and renal dysfunction. Timely diagnosis and intervention are imperative, and, therefore, we recommend the early use of arteriography using digital subtraction angiographic techniques for the definitive diagnosis.

Erroneous pressure measurement due to artificially deformed vessel during angioplasty.

Percutaneous transluminal angioplasty is a commonly performed procedure. The clinical success of such a procedure is determined by the combination of the post-procedure angiographic appearance and the pressure gradient across the lesion. This case demonstrates the importance of recognizing the anatomical variation if proper pressure measurements are to be obtained.

Endometrial papillary adenocarcinomas: two clinicopathological types.

Thirty-four patients with primary endometrial papillary adenocarcinoma diagnosed in our institution from 1970 to 1982 were studied. Papillary adenocarcinomas represented 10% of all endometrial adenocarcinomas seen during this period. Papillary neoplasms were morphologically subclassified as either papillary serous adenocarcinoma or well-differentiated papillary adenocarcinoma, following review of the histological sections obtained prior to radiotherapy or chemotherapy. Twenty-five patients were found to have papillary serous adenocarcinoma, and nine had well-differentiated papillary adenocarcinoma. A control group of 305 patients with endometrial adenocarcinoma of nonpapillary type was compared with respect to age, race, and survival. Fifty percent of the patients with papillary serous adenocarcinoma were black and they were significantly older (p = 0.001) than the control group, with a mean age of 71 years. Thirty percent of the papillary serous adenocarcinoma group had deep myometrial invasion and peritoneal surface involvement by tumor. In 20% of these patients there was a discrepancy between the clinical stage and the surgical stage at laparotomy. Survival was markedly worse (p = 0.01) than that of the control group. Patients with well-differentiated papillary adenocarcinomas were similar to control patients with respect to age and racial status and had similar clinical survival outcome. We conclude that well-differentiated papillary adenocarcinoma of the endometrium is a distinct form of papillary adenocarcinoma, and must be morphologically and clinically distinguished from papillary serous adenocarcinomas because of its better prognosis. Morphological differentiation of these two papillary variants of endometrial adenocarcinoma is presented.

Type B aortic dissection complicating renal artery angioplasty and stent placement.

Percutaneous renal artery stent placement has been demonstrated to improve blood pressure control and stabilize renal function in patients with atherosclerotic renal artery disease. However, this procedure is not without risk of significant morbidity, and its effectiveness, as compared to alternative treatments, has not been adequately established. The authors report a case of acute type B aortic dissection complicating renal artery stent placement. The authors postulate that an intimal disruption occurred during initial balloon angioplasty, and that repeated application of radial, shear, and torque forces during stent placement may have extended the injury. The diagnosis of acute aortic dissection should be considered in patients with suggestive symptoms immediately after stent placement.

High-powered CO2 laser cystoscope for endoscopic bladder surgery.

BACKGROUND AND OBJECTIVE: The CO2 laser is potentially useful for the surgical treatment of superficial bladder tumors. High water absorption of the CO2 laser beam and the lack of a flexible fiber delivery system has hindered development of cystoscopes designed to evaporate bladder tumors. This report describes a cystoscope capable of delivering a high-power CO2 laser beam to all parts of the urinary bladder. STUDY DESIGN/MATERIALS AND METHODS: A rigid 24 Fr. cystoscope transmitting 80 Watts of power via an articulated arm and infrared waveguide was built. Beam manipulation is by reflection using a movable mirror. Smoke and urine are evacuated by continuous flow of CO2 purge gas. An isotopic laser delivering an 11.1 micron wavelength beam prevents resonant absorption. Conventional 30-70 degrees telescopes are used. Scope performance and lesion morphology were tested in four female pigs. RESULTS: A total of 80-85% of the incident energy is delivered to the mucosa. All areas of the bladder mucosa can be evaporated. All components tolerate wetting. Mucosa and lamina propria are evaporated with 30 Joules of delivered energy. Perforation occurs after 120-160 Joules are delivered to a single spot. CONCLUSION: The limitations of power, beam transmission, beam manipulation within a small cavity, and resistance to wetting have been overcome.

Therapeutic use of albumin.

Increasing use of normal human serum albumin may be contributing to the rising cost of medical care. To investigate whether albumin is extensively overused or abused, a study of the quality of albumin use was conducted in a Veterans Administration Hospital. Specific criteria for appropriate use were developed using guidelines defined at a national symposium. A review of use during a three-month period showed that surgery patients received 91% of the albumin administered during that period; of the total amount administered, 41% was used inappropriately; the decision to administer albumin to patients undergoing surgery appeared to be correct only 29% of the time; and an estimated $40,000 was spent on inappropriately used albumin at this hospital in 1977.