Scar sign of renal oncocytoma: Magnetic resonance imaging appearance and lack of specificity

This case report illustrates the magnetic resonance imaging (MRI) appearance of a typically asymptomatic renal oncocytoma as a homogeneous mass of medium signal with a stellate central region of decreased signal, representing the central scar. The MRI was correlated with computed tomography (CT), ultrasound (US), and gross pathologic appearance. The appearance of a central scar is not specific for oncocytoma and does not exclude renal cell carcinoma, as illustrated by a second case.     

Optimal use of coronary care units: A review

Patients at a low probability of acute cardiac pathology constitute a considerable proportion in many coronary care units (CCUs), such that physicians should consider more effective alternatives than CCU admission “to rule out myocardial infarction.” In this article, strategies to increase the efficiency of managing patients with acute chest pain are reviewed. Algorithms aiming to improve the diagnostic accuracy of the general practitioner have been developed but require an electrocardiogram recorded at the home of the patient. Another method of triage encompasses the identification in the emergency room of the hospital of patients at a low probability of acute cardiac pathology by using predictive models that include laboratory assessments. A third strategy includes alternatives to CCUs for patients at a low risk of acute cardiac pathology, such as the creation of a simple observation unit. Finally, some investigators have sought to identify patients with good prognosis for early transfer from the CCU to lower levels of care. It is concluded that a combination of these approaches will be most efficient, and that the most appropriate choice will be determined by local circumstances.     

Contralateral reinnervation of midline muscles in nonidiopathic facial palsy.

The purpose of this study was to analyze contralateral reinnervation of the facial nerve in eight patients with complete facial palsy after surgery or trauma and seven healthy volunteers. All patients had contralateral reinnervation of facial muscles as demonstrated by electrical nerve stimulation versus none of the control subjects. Four patients had facial muscle movements at the site of the damaged nerve. In one patient this was entirely the result of contralateral reinnervation, whereas the other three patients had innervation both ipsilaterally and contralaterally. This implies that renewed facial muscle activity should be examined considering the origin of the reinnervation, either contralateral or ipsilateral. Contralateral reinnervation is a common phenomenon after total facial palsy and can occur alongside ipsilateral reinnervation. It can be mistaken for adequate reinnervation of the damaged nerve, causing postponement of dynamic reconstruction therapy.     

MR imaging of extraabdominal desmoids: differentiation from other neoplasms.

A retrospective review of MR images of 36 patients with histologically proved extraabdominal desmoids was done to define the MR characteristics of these tumors and to determine if MR could be used to differentiate desmoids from other benign and malignant soft-tissue neoplasms. The desmoids evaluated included eight primary and 30 recurrent lesions. Our study was conducted in parallel with another study in which the MR appearance of 95 benign and malignant soft-tissue masses was evaluated, and the MR images of these masses were compared with our findings. The four desmoids from that study are included in our data. The signal intensity of the tumor on T1- and T2-weighted images was graded relative to the intensities of muscle and fat. Homogeneity, margin, neurovascular and bone involvement, and fibrosis (low-signal regions within the tumor on both T1- and T2-weighted images) were evaluated. On MR imaging, the desmoids showed inhomogeneous signal (97%), poor margination (89%), neurovascular involvement (58%), and bone involvement (37%). Fibrosis was present in 88% of primary desmoids and 90% of recurrent ones, and intermediate signal (greater than that of muscle and less than that of fat) was present in 75% and 50% of these, respectively. Our results show that the MR features of desmoids have characteristics that are commonly found in malignant tumors (inhomogeneous signal, poor margination, and neurovascular involvement). MR features of desmoids that distinguish them from malignant neoplasms are the presence of fibrosis and intermediate signal in the regions of the tumor.     

Inversion lateral ankle trauma: differential diagnosis, review of the literature, and prospective study

This study is comprised of 71 patients with inversion injuries. The purpose of this article is to present a logical and orderly approach in evaluating these injuries. A comprehensive review of the literature concerning diagnostic techniques and mechanisms of injury related to inversion ankle trauma is presented. Inversion ankle injuries are frequently misdiagnosed as simple sprains when frequently there are other pathologies present. The standard approach of evaluating inversion ankle injuries is often inadequate.     

Autologous whole plasma fibrin gel. Intraoperative procurement.

Fibrin glue is a relatively recent addition to the armamentarium of hemostatic agents for surgical use. Its efficacy has been repeatedly demonstrated in almost all surgical disciplines and subspecialties. Its use in the United States has been limited because of the risk of viral transmission associated with the use of human plasma. Previous authors have described techniques that limit this risk, but they are frequently impractical, expensive, or cumbersome. We describe the use of patients' own fresh plasma to make fibrin gel at the operative field. It provided hemostasis at least as good as that from heterologous plasma glue in 40 cardiac surgical patients. Autologous whole plasma fibrin gel is inexpensive and safe and eliminates the risk of viral transmission associated with glue derived from heterologous donor plasma.     

Effects of nisoldipine on coronary collateral perfusion and hemodynamics in chronically instrumented dogs

The effect of a new dihydropyridine slow-channel calcium blocking agent, nisoldipine, on hemodynamics and myocardial blood flow in normal and collateral-dependent areas distal to a chronic coronary artery occlusion were studied in chronically instrumented, conscious dogs. Nisoldipine produced significant and dose-related decreases in arterial blood pressure, an elevation of heart rate and large increases in coronary blood flow velocity. In dogs with an Ameroid constrictor previously implanted to enhance coronary collateral development, this agent produced large increases in perfusion distal to a chronic coronary artery occlusion. In addition, despite a reduction in arterial pressure, nisoldipine preserved renal cortical, intestinal and skeletal muscle blood flow while increasing tissue flow within liver and cerebral cortex. Thus, nisoldipine increases oxygen supply to collateral-dependent myocardium in the presence of reduced driving pressure for collateral perfusion.