Biomedical subjects

J Canady

Publications and source records attributed to J Canady.

10 recordsLinked to original sources

PubMed2006

Structure and function of the superior temporal plane in adult males with cleft lip and palate: pathologic enlargement with no relationship to childhood hearing deficits.

BACKGROUND: In a previous study from our lab, adult males with non-syndromic cleft lip and/or palate (NSCLP) were shown to have significantly lower temporal lobe gray matter volume than matched controls. The current study was designed to begin a regional analysis of specific subregions of the temporal lobe. The superior temporal plane (STP) is a brain region involved in the governance of auditory processing and aspects of language. The cognitive deficit of subjects with NSCLP is characterized by specific deficits in language; therefore this region of the temporal lobe is particularly important to investigate in this population. The STP has been found to be structurally abnormal in subjects with dyslexia, another developmental disorder involving language deficit. The hypothesis for the current study was that the STP in subjects with NSCLP would be structurally abnormal and that the abnormality would be related to cognitive deficit, but not to developmental hearing deficit. METHODS: Manual tracing of the STP in NSCLP males and matched controls was performed on magnetic resonance imaging (MRI) scans. Ratios of STP to total temporal lobe gray matter volume were calculated and compared across groups. In addition, the morphology of the STP was correlated to cognitive function as well as measures of hearing deficit during infancy and childhood. RESULTS: Despite overall deficit in temporal lobe gray matter, the STP is disproportionately large in subjects with NSCLP compared to controls. Further, gray matter volume of the STP was inversely correlated with IQ and language test scores in CLP subjects. Hearing loss throughout childhood and adulthood was not significantly correlated with brain morphology. CONCLUSIONS: The structure of the superior temporal plane in adult males with NSCLP was disproportionately large. This abnormally increased volume was directly related to IQ, with greater STP volume being associated with lower cognitive functioning, thus characterizing the finding as 'pathologic enlargement'. Moreover, there was no relationship between the structure of the STP and measures of childhood hearing impairment, supporting the notion that the language deficits of this population are more likely due to abnormal brain development than to the effects of hearing deficit during childhood.

Adolescent↗

PubMed2001

Increased incidence of a midline brain anomaly in patients with nonsyndromic clefts of the lip and/or palate.

BACKGROUND AND PURPOSE: Nonsyndromic clefts of the lip and palate (CLP) are developmental craniofacial abnormalities that are often associated with cognitive dysfunction. This study was designed to evaluate, in patients with CLP, the presence of a specific midline brain anomaly (enlarged cavum septi pellucidi [CSP]) that has been shown in other developmental syndromes to be related to poor cognitive function. METHODS: Brain images were obtained using magnetic resonance imaging on 49 adult men with CLP and 75 healthy controls. Size of CSP was measured using consecutive coronal images. RESULTS: The incidence of large CSP in the CLP group was 8% (4 of 49), significantly higher than that found in the control group. In 2 of these 4 subjects, the anomaly was complete nonfusion of the septal leaflets, known as a combined CSP and cavum vergae. Furthermore, there was a significant inverse relationship of IQ and CSP in CLP patients that was not present in controls. That is, in individuals with CLP, the larger the CSP, the lower the IQ. CONCLUSIONS: Adult men with CLP have an increased prevalence of enlarged CSP. Moreover, this anomaly is directly related to cognitive deficits. This study provides further evidence that the development of the face and the development of the brain are intimately related and that defects in craniofacial development are most likely associated with defects in brain development.

Adult↗

PubMed2001

Investigations of a pressure-sensitive theory of marginal velopharyngeal inadequacy.

PURPOSE: This two-part project was designed to test a pressure-sensitive theory of marginal velopharyngeal inadequacy (MPVI). Specifically, are select subgroups of children with MPVI perceived as hypernasal because they fail to achieve consistent closure during vowels and semivowels while demonstrating adequate closure during pressure consonants? METHODS: In part one, 36 children with cleft palate and other craniofacial anomalies were examined using a clinical assessment protocol that included nasometry and perceived ratings of hypernasal resonance. Children with nasalance percentages above threshold during low-pressure (LP) productions and below threshold for high-pressure (HP) productions were placed in one group (group 1), while children with nasalance percentages below threshold for both LP and HP sentences were placed in another (group 2). Children in the two groups were age- and sex-matched. In part two, endoscopic data were examined for 10 additional children who received nasometry, perceived hypernasal resonance scores, and videoendoscopy on the same day and who received higher mean nasalance measures during production of LP sentences than during production of HP sentences. RESULTS: The results of part one confirmed that children in group 1 were perceived as being significantly more hypernasal than children in group 2 (mean(group 1) = 2.17, mean(group 2) = 1.50; t = 2.75, p =.01). However, results of endoscopic testing failed to demonstrate a consistent observable physiologic pattern of velopharyngeal inadequacy that would confirm the theory that some patients with MVPI are perceived as being hypernasal because of difficulty achieving velopharyngeal closure during vowels and semivowels. CONCLUSIONS; The findings provide partial support for a pressure-sensitive theory of MVPI and demonstrate the value of using both HP and LP sentences to evaluate patients with MVPI.

Adolescent↗

PubMed2001

Transient radiculopathy after 5% lidocaine or 0.75% bupivacaine spinal anesthesia in 3 surgical positions.

The present study was conducted to compare the incidence of transient radicular irritation (TRI) after spinal anesthesia with 5% lidocaine or 0.75% bupivacaine in the supine, prone, and lithotomy surgical positions. A non-rAndomized survey approach was used. The convenience sample consisted of 243 adults receiving spinal anesthesia for elective surgery at 1 of 3 hospitals. Patients were questioned by telephone postoperatively to determine whether they had experienced TRI. Statistical analysis using the Fisher exact test revealed no significant difference in TRI incidence between local anesthetics in the supine or prone position groups. In the lithotomy position group, the incidence of TRI was significantly higher in patients receiving 5% lidocaine. Further, chi 2 testing revealed no significant difference in TRI incidence between surgical position groups when position alone was considered. The findings suggest that TRI after spinal anesthesia occurs more frequently with 5% lidocaine than with 0.75% bupivacaine only when patients undergo surgery in the lithotomy position. Providers need to consider the risks and benefits of 5% lidocaine when selecting an agent for spinal anesthesia, especially with patients undergoing surgery in the lithotomy position. When lidocaine is used, providers should discuss TRI as a risk of spinal anesthesia with patients during preanesthetic counseling.

Adult↗

PubMed2000

Abnormal brain morphology in patients with isolated cleft lip, cleft palate, or both: a preliminary analysis.

OBJECTIVE: The aim of this study was to determine whether adult men with cleft lip and palate (CLP) have aberrant cerebral morphology. DESIGN: Brain morphology of 14 adult men with isolated CLP were analyzed and compared with 14 healthy controls matched for sex, age, and parental socioeconomic status. SETTING: The research took place at a large, tertiary care hospital, with participation on an outpatient basis. PARTICIPANTS: The 14 males with CLP were recruited from a large cleft lip and palate registry, while their 14 matched controls were selected from a registry of healthy volunteers collected via the Mental Health Clinical Research Center. RESULTS: The males with CLP have significantly smaller cerebellar size (p = .04), significantly larger frontal lobes (p = .02), and significantly smaller temporal and occipital lobes (p = .02; p = .009, respectively). No significant difference in gray/white matter ratios or laterality were found. CONCLUSIONS: Adult males with CLP have a significantly different pattern of brain morphology, compared with healthy controls, which is most likely due to aberrant cerebral development. This study highlights the complex interaction and interdependence of craniofacial and cerebral development.

Adult↗

PubMed2000

Symmetrical peripheral gangrene: a new presentation of an old disease.

This report concerns two cases and a review of the literature on the subject of symmetrical peripheral gangrene. Symmetrical peripheral gangrene is defined as symmetrical distal ischemic damage in two or more sites in the absence of major vascular occlusive disease. It occurs in patients who are septic and have disseminated intravascular coagulation and in nonseptic patients who have cardiogenic or hypovolemic shock. The syndrome is devastating and rare, and controlled studies of its etiology and management are lacking. Recommendations are presented for its prevention and treatment. Cooperative multicenter studies may be necessary to obtain valid data about its prevention and management.

Aged↗

PubMed1991

Endovascular management of arterial intimal defects: an experimental comparison by arteriography, angioscopy, and intravascular ultrasonography.

To determine the feasibility of the endovascular management of intimal defects while comparing the accuracy of arteriography with angioscopy and intravascular ultrasonography, we developed an in vivo model of arterial intimal flaps. In 10 superficial femoral arteries of five anesthetized mongrel dogs, intimal flaps were constructed and then imaged by arteriography, angioscopy, and intravascular ultrasound. A flexible microbiopsy forceps was used to remove each intimal flap under angioscopic guidance. Arteriographic lumen diameters were measured and cross-sectional areas calculated. Corresponding measurements by angioscopy and intravascular ultrasound with reduction in luminal area at the flap were obtained by use of computerized planimetry. Uniplanar arteriography identified 60% (6/10) of the intimal flaps, whereas angioscopy and intravascular ultrasound demonstrated 100%. Lumen diameter (in millimeters) measured by arteriography (3.4 +/- 0.6) correlated significantly with measurements by angioscopy (3.5 +/- 0.5, r = 0.77) and intravascular ultrasound (3.5 +/- 0.6, r = 0.96). Similarly, lumen area (square millimeters) by arteriography (9.2 +/- 2.9) correlated with measurements by angioscopy (8.9 +/- 2.2, r = 0.82) and intravascular ultrasound (8.6 +/- 2.7, r = 0.91). Reduction in lumen area by the flap by angioscopy (37 +/- 7%) and intravascular ultrasound (33 +/- 8%) also correlated significantly (r = 0.72). The intimal flaps were removed successfully in all 10 arteries as confirmed by arteriography, angioscopy, and intravascular ultrasound. We conclude that the endovascular management of intimal defects is possible. Additionally, angioscopy and intravascular ultrasound accurately evaluate lumen diameter and area while providing direct assessment of intimal defects.

Animals↗

PubMed1989

Use of naloxone in septic shock.

Experimental and clinical evidence show that endogenous opiates (endorphins) contribute to the pathophysiology of circulatory shock. The authors evaluated the effectiveness and safety of continuous infusion of naloxone in five septic patients with prolonged hypotension unresponsive to volume replacement and dopamine infusion. Naloxone (2 mg bolus) was intravenously administered and continued at 0.25 mg/hr for 24 to 48 hours. All five patients had significant increase in mean arterial pressure of between 20 and 30 mmHg (P less than 0.0012). Cardiac index, systemic vascular resistance, and pulmonary arterial pressure were not significantly altered; however, there was a significant difference in pulmonary capillary wedge pressure (P less than 0.034) and urinary output (P less than 0.0273). Subjects did not experience side effects with naloxone. We conclude that continuous infusion of naloxone can reverse endorphin-mediated hypotension in septic shock patients.

Aged↗

PubMed1987

Intestinal obstruction: still a lethal clinical entity.

A retrospective analysis of 70 consecutive patients with a clinical diagnosis of intestinal obstruction from January 1983 to September 1985 was reviewed. Mean age was 62 years. Etiological factors included adhesions 50 percent, malignancy 24 percent, volvulus 12 percent, diverticulitis 7 percent, hernias 4 percent, and radiation enteritis, mesenteric infarction, and perforation of the cecum in the remaining 3 percent. Complications included wound infection 9 percent (n = 6), intra-abdominal sepsis 7 percent (n = 5), and recurrent small bowel obstruction 4 percent (n = 3). Overall mortality was 24 percent (n = 7).Results of the univariant analysis showed no association between the clinical signs of intestinal obstruction, that is, fever, tachycardia, leukocytosis, and local tenderness, and gangrenous bowel. A multiple regression analysis showed, however, that only 14 percent of the variance was able to predict the gangrenous bowel based on clinical signs. In conclusion, the classical signs of intestinal obstruction are poor indicators for compromised bowel, and early surgical intervention will reduce the incidence of ischemic bowel and mortality.

Adolescent↗

PubMedDate not supplied

Role of heparin in reducing skeletal muscle infarction in ischemia-reperfusion.

Heparin continues to be recommended in the clinical management of limb ischemia to prevent extension of distal vascular thrombosis and increased rates of limb loss. However, heparin may also be responsible for reduced skeletal muscle injury. Although its mechanism of action has not been fully evaluated, we have investigated the ability of heparin to minimize skeletal muscle injury associated with the ischemia-reperfusion syndrome in an in vivo canine gracilis muscle model. Our findings demonstrated a significant reduction in the amount of skeletal muscle infarction, microvascular permeability, and H+ ion accumulation cumulation after preischemic heparinization. Diffuse intravascular coagulation also has been observed in observed in this model which may be prevented or reduced by the anticoagulant properties of heparin when administered prior to ischemia. However, heparin's protective effect may be independent of its anticoagulant activity. Heparin is a polycomponent drug with non-anticoagulant properties which may serve to reduce cellular injury during ischemia and reperfusion in several different ways. Microvascular injury is decreased by the restoration of normal intimal negative charge and through the binding and resultant inactivation of histamine, bradykinin and other vasoactive amines. Heparin inhibits the complement cascade which is known to determine ischemic infarct size. Other factors of importance in determining the extent of skeletal injury include neutrophil activation, chemotaxis, enzyme release, and free oxygen radical generation, all of which are decreased or modulated by heparin. Heparin is a complex substance and much more remains to be learned about its anticoagulant and nonanticoagulant properties as well as its protective effects on skeletal muscle injury in ischemia-reperfusion syndrome.

Animals↗