Posttraumatic pseudomeningomyelocele (enlarging fracture?) in a vertebral body. Case report.

An unusual case is reported in which a posttraumatic peudomeningomyelocele developed over many years inside the body of a fractured lumbar vertebra, eroding the pedicle and causing progressive neurological deficit. The wall of the sac was mostly formed by the scalloped bar bone, and partly by a membrane resembling the dura. The terminal part of the conus medullaris and some nerve roots of the cauda equina formed the contents and parts of the wall of the outpouching of the subarachnoid space into the vertebral body. A comparison is drawn between this lesion and formation of an "enlarging fracture" of the skull. The surgical technique used for obliteration of this pseudomeningomyelocele is described.

The visiting lectureship on aboriginal health: an educational initiative at the University of Toronto.

Many recent reports on Aboriginal issues have identified three major deficits in Canadian universities: a lack of Aboriginal curriculum content, a lack of faculty role models, and low student enrollment. Many health professional schools have responded by recruiting more Aboriginal students and by introducing Native content into their curricula. This paper describes the six-year experience of the annual program of the Visiting Lectureship on Native Health at the University of Toronto as one of the ways to increase the Aboriginal curricular content. The three-week program covers the selected Aboriginal health issue by sequentially exploring its historical background, the extent of the current problem and its future solutions. Over six years, 37 Native speakers delivered 83 lectures, 19 public fora and 98 seminars and workshops to 3 universities and 12 professional and community agencies. Over 7,900 individuals have participated in the program and the response has been very positive.

Clinical differentiation of narrow QRS complex tachycardias.

Supraventricular tachycardias generally present with narrow QRS complexes and are quite commonly seen in the emergency department. Regular narrow QRS complex tachycardias occur in all age groups and may be associated with minimal symptoms, such as palpitations, or, present with hemodynamic compromise resulting in syncope. While history and physical examination are indispensable, they usually do not lead to a definitive diagnosis. The diagnosis is made by careful analysis of the 12-lead ECG. Therapy is based on hemodynamic assessment and understanding of the tachycardia mechanism.

Clinical approach to wide QRS complex tachycardias.

Wide QRS complex tachycardia is a frequently encountered arrhythmia in the emergency department and presents a diagnostic challenge to the emergency physician. The history, physical examination, chest radiograph, and electrocardiogram analysis are important in making the correct diagnosis. The diagnosis of ventricular tachycardia is supported by, 1) a history of prior myocardial infarction or congestive heart failure; 2) a physical examination showing cannon A-waves in the jugular venous pulsation or variable heart sounds; 3) a chest radiograph showing cardiomegaly or evidence of prior cardiac surgery; and 4) characteristic ECG features that include AV dissociation, fusion-capture beats, QRS concordance, or, typical morphologic features in leads V1 and V6. This article presents the diagnostic and therapeutic approaches to wide QRS tachycardias.

Permanent cardiac pacing.

Implantation of a permanent pacemaker is the most commonly performed surgical operation involving the heart. The modern cardiac pacemaker is a complex device that can sense and pace in both the atrium and ventricle. It also modulates the pacing rate based on sensed physiologic parameters. This article reviews the fundamental principles of pacemaker technology and provides the emergency physician with approaches to common pacemaker problems.

Implantable cardioverter defibrillators.

Implantable cardioverter defibrillators have proven to be an effective therapy for life-threatening ventricular arrhythmias. Given the ever-increasing number of patients who have these devices, increasing numbers of patients are likely to present to emergency departments with defibrillator-related problems. This article discusses normal device function, indications for implantation, and technique of implantation. It also focuses on the evaluation and management of patients with these devices presenting to the emergency department.

Spongy left ventricular myocardium in an adult.

"Spongy left ventricular myocardium," or noncompaction of left ventricular myocardium, is a rare disorder of endomyocardial morphogenesis. It is usually seen in the pediatric population and is often associated with other congenital cardiac malformations. We describe an adult with noncompaction of left ventricular myocardium without associated congenital cardiac anomalies.

Adenosine-induced ventricular fibrillation.

The use of adenosine has been suggested as a diagnostic tool in the evaluation of wide ORS complex tachycardia. However, adenosine shortens the antegrade refractoriness of accessory atrioventricular connections and may cause acceleration of the ventricular rate during atrial fibrillation. We observed ventricular fibrillation in 2 patients who presented to the emergency department with pre-excited atrial fibrillation and were given 12 mg of adenosine.

A comparative bacteriological profile and antibiogram of dacryocystitis.

INTRODUCTION: Dacryocystitis is an infection and an inflammation of the lacrimal sac and is an important cause of ocular morbidity in India. OBJECTIVE: To isolate and identify the bacterial patterns associated with dacryocystitis and to determine their antibacterial sensitivity pattern. MATERIALS AND METHODS: A total of 100 lacrimal swab materials were subjected to bacterial analysis. Children less than 8 years were not included in the study. RESULTS: The chances of chronic dacryocystitis were more than acute dacryocystitis and were commonly found in the age group of 41 - 50 years. Females were more vulnerable to the infection than males. From a 100 samples a total of 122 bacterial isolates were obtained. Both Gram positive and Gram negative bacteria were equally distributed in the study. The most common organism associated with the infection was S. aureus. The antibacterial sensitivity showed more effectiveness towards Gram positive isolates than Gram negative isolates. CONCLUSION: Both Gram positive and Gram negative organism are associated with with chronic dacryocystitis. Knowledge of the bacteriology of dacryocystitis and the susceptibility of the bacteria towards antibiotics will better guide a clinician in the choice of the medication for the most appropriate drug for the treatment.

Dilution induced thickening in hydrotrope-rich rod-like micelles.

Dilution induced changes in the microstructure and rheological behavior of micelles formed by a cationic surfactant-anionic hydrotrope mixture has been investigated in the hydrotrope-rich region. The surfactant used is cetyltrimethylammonium bromide (CTAB) and the hydrotropic salt is sodium 3-hydroxy naphthalene 2-carboxylate (SHNC). The concentration of the mixture is varied from 0.5% to 10.0% w/w (φ=0.005-0.100) at a fixed weight ratio of hydrotrope to surfactant (85:15). Rheological studies indicate Newtonian flow behavior at low and high volume fractions (0.005 and 0.100) while a shear thinning behavior is observed at intermediate volume fractions. The zero-shear viscosity η(0) also passes through a maximum upon changes in the concentration. The most striking feature in our study is that a low viscosity Newtonian fluid transforms to a viscoelastic fluid, upon dilution, and then again to a Newtonain fluid. Small angle neutron scattering studies of 10.0% micellar solution show the presence of rod-like aggregates. Upon dilution, the scattering intensity per unit concentration shows an increase in the low q-region. The nature of pair distance distribution function and subsequent model fitting indicates a transition from rod-like micelles to unilamellar vesicles upon dilution. This behavior is explained in terms of the volume fraction dependant solubilization of hydrotropes in the rod-like micelles and consequent changes in the composition of the mixed micelles.