Percutaneous Nd:YAG Laser Coagulation of Ventricular Myocardium in Dogs Using a Special Electrode Laser Catheter

A novel catheter system was used for intracardiac electrogram recordings, ventricular pacing and continuous-wave Nd:YAG laser (1,064 nm) irradiation of ventricular myocardium in eight dogs. Radiation at a power of 10 W for 3, 5, and 10 seconds was delivered through a 400 microns optical fiber. Power density was 15 W/mm2. A total of 96 laser injuries (12 per dog) were produced in selected sites in both the right and the left normal canine ventricle. Ventricular arrhythmias were noted during 12 of 96 (12.5%) laser pulses. Programmed electrical stimulation performed during control study immediately (all dogs) at 2 days (two dogs), and 4 months (4 dogs) following the experiments showed no episodes of sustained or nonsustained ventricular tachycardia. Radiation energies up to 50 J (10 W over 5 s) caused focal injuries of homogeneous coagulation/fibrosis localized to the target area, without vaporizing tissue and forming craters. Morphometrically and histologically there was a direct relationship between the energy of radiation delivered, and the extent and severity of the injury produced. The maximum size of lesions measured 7/11 mm (diameter/depth). Using a special catheter system laser coagulation of myocardium can be accomplished percutaneously. This method can create controlled subendocardial injuries without major side effects and appears to overcome most disadvantages of transcatheter high energy direct-current shocks when used as a regular course of procedure in ablation of arrhythmogenic tissue in the heart.     

Basement membrane components outline the tumour islands in cylindroma

The main histological feature of cylindroma is the deposition of sheaths of a‘hyalinized’ material contiguous to the tumour cell clusters. Although ultrastructural studies of this material have revealed a basement membrane-like structure, its exact nature has remained unclear. Using immuno-staining with affinity-purified antibodies directed against distinct basement membrane components, we have shown that type IV collagen and laminin are major constituents of this zone. In addition, cell culture studies indicated that both proteins are synthesized by the tumour cells. The immunohistological data make it clear that the tumour matrix between the tumour cell islands is composed not only of basement membrane components, but also is composed of other connective tissue constituents, i.e. type I and III collagen and fibronectin.     

Impact of chronic condition status and severity on dental treatment under general anesthesia for Medicaid‐enrolled children in Iowa state

Objective: To assess the impact of chronic condition (CC) status and CC severity, respectively, on the odds of receiving dental treatment under general anesthesia (GA) for Medicaid‐enrolled children by age group. Methods: This was a retrospective analysis of Iowa Medicaid‐enrolled children <15 years (n = 62 721) from 2005 to 2008. 3M Clinical Risk Grouping Software identified each child’s CC status (yes/no) and assigned children with a CC into a hierarchal CC severity group (episodic/life‐long/complex). Multiple variable logistic regression models were used to identify the determinants of dental treatment under GA. Results: Less than 1% of children received dental treatment under GA. While there was no significant difference in dental treatment under GA by CC status for children <6, those with a life‐long CC were twice as likely to receive dental treatment under GA as demographically similar children with an episodic CC (P < 0.05). Children ages 6–14 with a CC were three times as likely as those without a CC to receive treatment under GA (P = 0.001). There was also a direct relationship between CC severity and dental treatment under GA use for older children. Those living in nonmetropolitan areas were more likely to receive treatment under GA as were children who previously received dental treatment under GA. Conclusions: Chronic condition status and severity were more important determinants of dental treatment under GA for Medicaid‐enrolled children ages 6–14 than for those <6. Understanding these relationships is a critical step in developing clinical strategies and interventions aimed at preventing dental disease for Medicaid‐enrolled children whose reasons for needing dental treatment under GA are modifiable.     

Continuous acid-base assessment of the human fetus during labour by tissue pH and transcutaneous carbon dioxide monitoring

Summary. Simultaneous monitoring of fetal tissue pH (t-pH) and transcutaneous carbon dioxide (Tc- P co₂) was performed in 30 labours. Both t-pH and Te- P co_-2 at delivery were positively correlated with pH ( r = 0·69) and P co₂( r = 0·68) of the umbilical artery blood. A tissue/transcutaneous standard base excess (t-SBE) was derived from the t-pH and the Tc- P co₂ and calculated for 13 fetuses a t delivery; there was a correlation with standard base excess of umbilical artery blood. An analysis of t-pH and Tc- P co₂ changes during the last hour of labour revealed that only infants who were born with decreased pH of the umbilical artery blood had decreasing t-SBE, while all others had a constant t-SBE.     

Increased tone of the rectal wall in response to feeding persists in patients with cauda equina syndrome

The aim was to study fasting and postprandial rectal tone in patients with cauda equina injury. Electromechanical barostat measurement of rectal tone was made in 13 healthy volunteers and in five patients during a 10 min recording, while fasting and for 1 h after a 1000 kCal intake. A prompt decrease of rectal volume was observed in all control subjects and patients. The delay between the end of the meal and the onset of the rectal response was always less than 3 min in the five patients as well as in the control group. The rapidity of the rectal response to feeding observed in our five patients suggests that the rectal response was mediated via a neural or neurohumoral pathway despite severe injury of the sacral parasympathetic supply.     

Team-based approach reduces learning curve in robot-assisted laparoscopic radical prostatectomy

AIM: We assessed the team approach in reducing the learning curve during our 2-year experience transiting from open to robot-assisted laparoscopic radical prostatectomy (rLRP). METHODS: A team of three urologists progressed through assistant phase to console phase to obtain competency in robotic prostatectomy. One hundred patients underwent rLRP by this team using the da Vinci robotic surgical system from 1 February 2003 to 15 May 2005. RESULTS: The immediate perioperative outcome was divided into three corresponding time frames and the results demonstrated gradual improvement in outcome parameters. The mean set-up time and dissection time were 24+/-14 min and 182+/-52 min, respectively. The mean perioperative blood loss was 272+/-240 mL, and 7% of patients (n=7) required blood transfusion. The mean duration of bladder catheterization was 8.4+/-4.1 days, and mean hospital stay was 2.9+/-1.6 days. There was no perioperative mortality or conversion to open radical prostatectomy. Major complications (4%) included urethrovesical leak requiring re-operation, postoperative cerebrovascular accident, and transient ureteric obstruction. Minor complications (7%) included minor urethrovesical leak, bladder neck stenosis, and urinary tract infection. Mean follow up was 6.6+/-5.0 months. Pathological assessment showed pT2 disease in 55% and pT3 in 45% of specimens. CONCLUSIONS: A team-based approach to robot-assisted LRP helped to reduce the learning curve of the procedure for individual surgeons and continued to show significantly lower perioperative blood loss, transfusion requirements and postoperative pain compared to open radical retropubic prostatectomy.