Cerebral palsy lifetime care – four musculoskeletal conditions

Cerebral palsy (CP) has always been considered a static condition in the neurological sense. Secondary and associated conditions that occur in the patient with CPcan progress over time and cause unwanted sequelae. This paper discusses four musculoskeletal conditions that present across the lifetime and can lead to progressive loss of function in the patient with CP. Patella alta can be particularly painful in the early adult years, limiting mobility particularly when associated with crouch gait. Adults with lower-extremity weight-bearing status having hip dysplasia, progressive over time, often develop pain and severe degenerative arthritis, with or without arthrodesis. Spondylolysis, particularly at the L5 S1 level, is fairly common in the ambulatory adult with diplegia and may, if not diagnosed early, progress to spondylolisthesis. Cervical stenosis appears to be more prevalent in adults with spastic quadriparesis and dystonia and is often associated with myelomalacia and/or radiculopathy. All four of these conditions may be lessened, or even prevented, with intervention and diagnosis in the younger years. Possible interventions and outcomes over time are discussed in the context of multidisciplinary team management of the individual with CP.     

Validating an automated sleep spindle detection algorithm using an individualized approach

The goal of the current investigation was to develop a systematic method to validate the accuracy of an automated method of sleep spindle detection that takes into consideration individual differences in spindle amplitude. The benchmarking approach used here could be employed more generally to validate automated spindle scoring from other detection algorithms. In a sample of Stage 2 sleep from 10 healthy young subjects, spindles were identified both manually and automatically. The minimum amplitude threshold used by the prana ^® (PhiTools, Strasbourg, France) software spindle detection algorithm to identify a spindle was subject‐specific and determined based upon each subject’s mean peak spindle amplitude. Overall sensitivity and specificity values were 98.96 and 88.49%, respectively, when compared to manual scoring. Selecting individual amplitude thresholds for spindle detection based on systematic benchmarking data may validate automated spindle detection methods and improve reproducibility of experimental results. Given that interindividual differences are accounted for, we feel that automatic spindle detection provides an accurate and efficient alternative approach for detecting sleep spindles.     

Incidence and risk factors for preincision hypotension in a noncardiac pediatric surgical population

Background: Routine monitoring of blood pressure is an essential part of perioperative care in adults and children. It is however not known whether intraoperative hypotension (IOH) is clinically important in the ‘healthy’ pediatric patient. This may be partly due to the lack of data on the incidence and consequences of IOH in this group of patients. We utilized the Brain Trauma Foundation definition of hypotension to describe the incidence of preincision hypotension (PIH) in a large pediatric noncardiac surgical population and identified risk factors for the occurrence PIH. Methods: We examined the electronic perioperative records of all children aged 1–17 years undergoing general anesthesia for noncardiac surgeries between January 2005 and June 2007 in our institution. Frequency and factors associated with PIH were computed. Binary logistic regression with forward step‐wise algorithm was used to examine factors associated with PIH. Results: There were 22 263 children of whom 57.6% were males. Most (94.9%) cases were elective, American Society of Anesthesiologists (ASA) I–II (79.5%) procedures. Inhalational induction was predominantly used in this cohort (67%) although 33% of patients had propofol either as a sole induction agent or as part of a ‘co‐induction’ regime. Single or multiple episodes of PIH occurred in 35.8% of patients. PIH was more common in patients with ASA ≥ III (P < 0.001); those with preoperative hypotension (P < 0.001); and following intravenous induction (P < 0.001) as well as propofol co‐induction (P < 0.001). On multivariate analysis the following were significant predictors of PIH: baseline hypotension, propofol co‐induction, age, ASA ≥ III, and long preincision period. Conclusion: Preincision hypotension is common in the pediatric surgical population undergoing general anesthesia. Factors independently predictive of PIH included high ASA status, pre‐existing hypotension, propofol co‐induction prolonged preincision period and adolescent age group. The importance of blood pressure monitoring, prompt recognition of hypotension and use of appropriate intervention is emphasized.     

Nightguard Vital Bleaching of Tetracycline-Stained Teeth: 54 Months Post Treatment

Abstract: Purpose: The purpose of this longitudinal whitening study was to determine the stability, post-treatment side effects, and patient satisfaction after 6 months of active treatment of tetracycline-stained teeth with 10% carbamide peroxide at 0 and 54 months post treatment.
Materials and Methods: Twelve patients who completed the study (80%) were contacted and asked to participate in a survey concerning their whitening experience. Subjects were asked whether there had been any change in the shade of their teeth after treatment, and if they had experienced any side effects that they believed were treatment-related. Eight of the twelve patients underwent clinical examination.
Results: Ten patients (83%) reported no obvious shade change or only a slight darkening not noticed by others. Two (17%) reported a slight darkening that is probably noticeable by other people, but no one reported moderate darkening or significant darkening back to original shade. All respondents (n = 12) denied having to have a crown or root canal that they believed was treatment-related. Examiners who compared preoperative and post-treatment photographs and Vita shade values were in agreement with the patients' perceptions of shade change. The degree of improvement was significant for both the immediate (0 mo) and the 54-month post-treatment comparison with the pretreatment shade (p < .005 and p < .01 respectively).     

Changes in Salmonid Communities Associated with Pesticide Runoff Events

Two agricultural runoff events involving the pesticide azinphos-methyl occurred in July 2002 on the Wilmot River, Prince Edward Island, Canada, resulting in the death of thousands of fish. The fish communities from three sites on this river had been sampled in 2001, permitting comparisons of brook trout (Salvelinus fontinalis) and rainbow trout (Oncorhynchus mykiss) populations before and after the events. Samples taken immediately after the runoff events suggested that brook trout suffered higher mortality than rainbow trout. Young-of-the-year fish were more affected than older age classes for both species. Sampling in 2003, a year after the pesticide runoff events, revealed salmonid communities that were still skewed towards rainbow trout, and a decrease in the 1+ age class density (2002’s young of the year) at affected sites. These results suggest a differential effect of the pesticide azinphos-methyl on salmonid species and age classes under natural conditions, and a subsequent change in population and community structure. The possibility of these pesticide runoff events selecting for rainbow trout, an exotic species, is a consideration in management of agriculturally impacted rivers.     

AUTOFLUORESCENCE GUIDED BIOPSY FOR THE EARLY DIAGNOSIS OF BLADDER CARCINOMA

Purpose

We validate the usefulness of laser-induced autofluorescence for the detection of bladder carcinoma.

Materials and Methods

We obtained and analyzed fluorescence spectra from 75 patients in whom bladder cancer was suspected. Tissue fluorescence was excited by a nitrogen laser using a quartz optical fiber placed in gentle contact with the area of interest. The laser-induced autofluorescence spectrum was recorded using an intensified optical multichannel analyzer system. Spectra were corrected for the spectral response of the optical system, and the ratios of laser-induced autofluorescence intensities (I) at 385 and 455 nm. (I₃₈₅/I₄₅₅) were determined. We had previously established this ratio as a diagnostic algorithm. We included only suspicious bladder lesions (erythematous, edematous, raised and so forth) that were difficult to diagnose by cystoscopy as well as areas from which random biopsies were obtained. The fluorescence ratio algorithm was applied to 130 bladder areas.

Results

Of the 130 biopsies obtained during routine cystoscopy 107 (82%) were nonmalignant by histological classification. In contrast, because laser-induced autofluorescence effectively guides biopsies towards malignant lesions, only 30 biopsies (72% fewer) would have been obtained from nonmalignant tissue if the fluorescence ratio that identifies 95% of malignant lesions (95th percentile) had been selected as the decision criterion during standard cystoscopy.

Conclusions

By guiding the surgeon to suspicious lesions that are most likely to be malignant, laser-induced autofluorescence substantially decreases the number of biopsies obtained from nonmalignant tissue during cystoscopy to diagnose bladder carcinoma.     

bcl-2 PROTEIN IS STRONGLY EXPRESSED IN POST-TRANSPLANT LYMPHOPROLIFERATIVE DISORDERS

The aim of this study was to examine a series of Epstein–Barr virus (EBV)-driven post-transplant lymphoproliferative disorders (PTLDs), in order to ascertain the level of bcl-2 immunostaining; to explore the relationship between bcl-2 and p53 protein expression; and to see if any correlation exists between bcl-2 and EBV-latent membrane protein 1 (LMP-1). Seventeen renal and 11 heart/heart–lung PTLD cases were stained with antibodies to EBV-LMP-1, bcl-2 and p53, using paraffin-embedded tissue. All cases of PTLD strongly co-expressed bcl-2 and EBV-LMP. Positive staining was present in small lymphoid and larger immunoblastic cells. These two antibodies showed parallel staining intensity. p53 expression was noted in 13 of 17 renal PTLDs, but in ten of the positive cases only 5–10 per cent of cells were stained. Seven of the 11 heart/heart–lung cases showed 50–60 per cent of cells to be p53-positive; in the remaining four cases, 10–20 per cent of cells were positive. bcl-2 protein, as detected by immunohistochemistry, is markedly overexpressed in all cases of PTLD. This study also demonstrates a strongly positive correlation between bcl-2 expression and EBV-LMP-1 detection in PTLDs. An inverse pattern of p53 and bcl-2 immunoexpression is noted in PTLDs with ‘high grade’ histology: these show marked expression of bcl-2, while p53 is downregulated. A Fisher's exact test yielded a P value of 0·12 when comparing p53-positive renal PTLDs with p53-positive heart/heart–lung PTLDs, indicating that any difference seen is not statistically significant. The postulated mechanism for the positive correlation between bcl-2 and EBV-LMP-1 is that EBV upregulates bcl-2, either directly or indirectly, thus promoting cell survival and ultimately successful viral replication.     

Combined Use of a True-Bipolar Sensing Implantable Cardioverter Defibrillator in a Patient Having a Prior Implantable Spinal Cord Stimulator for Intractable Pain

Reported is a case involving a patient with a previously implanted spinal cord stimulator (SCS) who presented for an implantable. Cardioverter defibrillator (ICD). The SCS device was located in the left lower abdominal quadrant with a stimulation electrode array placed on the dorsal aspect of the spinal cord at the T-11 thoracic level. Interaction testing demonstrated that the bipolar sensing transvenous ICD system (Medtronic 7221Cx PCD) did not detect the stimulator's output at burst rates ranging from 20–130 pulses/s, even with the ICD set to its maximum sensitivity of 0.15 mV and the stimulator programmed to the highest patient tolerated output combinations of 5 V, 0.45 ms in the bipolar configuration and 3 V, 0.45 ms in the unipolar (i.e., case-electrode) configuration.     

Programmed Electrical Stimulation Protocols: Variations on a Theme

A series of prospective protocols were designed to determine the yield ratio (true positives vs. false positives = nonclinical) in various patient groups using a variety of programmed electrical stimulation (PES) variables. First, a PES protocol was used in 772 patients. Single, double, and triple extrastimuli were delivered in sequence (leaving each successive extrastimulus just beyond its refractory period before moving to the next extrastimulus) during sinus rhythm and two ventricular paced rates at the RV apex, before moving to the outflow tract and repeating the sequence and then moving on to isoproterenol infusion with the PES sequence repeated at the apex. This protocol met NASPE standards for induction of VT in patients with coronary artery disease and a history of VT, while failing to induce monomorphic VT in any control patient. The best yield ratios combined with the greatest likelihood of inducing clinical tachycardia were achieved with sinus rhythm and three extrastimuli, and pacing at the lower rate and three extrastimuli. Pacing at the faster rate and triple extrastimuli was highly inductive of clinical arrhythmias, but had a low yield ratio due to induction of more nonclinical arrhythmias than other steps. The next protocol was performed in 61 patients with inducible ventricular tachycardia. In each case, the protocol described above was completed at the RV apex, even if tachycardia was also induced at an earlier point in the protocol. This allowed for more accurate yield ratios to be established for each step in the protocol, since each patient was exposed to each of these steps. The results confirmed those of the first protocol described above. The next protocol compared extrastimuli delivered (1) in a straight sequential fashion (each extrastimulus decremented to its refractory period and then left just late enough to capture while the next extrastimulus was added and decremented in a similar fashion); versus (2) the tandem method, in which after reaching refractoriness, each extrastimulus was moved 50 msec beyond the refractory period and then decremented in tandem with the next extrastimulus. Preliminary analysis of this protocol in > 30 subjects indicates no significant difference in the number of clinical or nonclinical arrhythmias induced with these methods, although the tandem method was much more time consuming. We conclude that a simple sequential PES protocol, taken to refractoriness, is efficient and effective, and is not at a disadvantage compared to more complex or cumbersome protocols.