Stereotactic Radiosurgery for Trigeminal Neuralgia in Patients With Multiple Sclerosis: A Multicenter Study.

BACKGROUND: Facial pain response (PR) to various surgical interventions in patients with multiple sclerosis (MS)-related trigeminal neuralgia (TN) is much less optimal. No large patient series regarding stereotactic radiosurgery (SRS) has been published. OBJECTIVE: To evaluate the clinical outcomes of MS-related TN treated with SRS. METHODS: This is a retrospective cohort study. A total of 263 patients contributed by 9 member tertiary referral Gamma Knife centers (2 in Canada and 7 in USA) of the International Gamma Knife Research Consortium (IGKRF) constituted this study. RESULTS: The median latency period of PR after SRS was 1 mo. Reasonable pain control (Barrow Neurological Institute [BNI] Pain Scores I-IIIb) was achieved in 232 patients (88.2%). The median maintenance period from SRS was 14.1 months (range, 10 days to 10 years). The actuarial reasonable pain control maintenance rates at 1 yr, 2 yr, and 4 yr were 54%, 35%, and 24%, respectively. There was a correlation between the status of achieving BNI-I and the maintenance of facial pain recurrence-free rate. The median recurrence-free rate was 36 mo and 12.2 mo in patients achieving BNI-I and BNI > I, respectively (P = .046). Among 210 patients with known status of post-SRS complications, the new-onset of facial numbness (BNI-I or II) after SRS occurred in 21 patients (10%). CONCLUSION: In this largest series SRS offers a reasonable benefit to risk profile for patients who have exhausted medical management. More favorable initial response to SRS may predict a long-lasting pain control.

Short-term Detection of Imidacloprid in Streams after Applications in Forests.

Imidacloprid, a neonicotinoid insecticide, is a major component of hemlock woolly adelgid (HWA) [ (Annand)] management programs that are critical to protecting forest health in the eastern United States. However, the impact of imidacloprid soil applications in forests on some aquatic macroinvertebrate species by leaching into aquatic systems is uncertain. The time for residues from imidacloprid soil applications to migrate from treated hemlocks to nearby streams and the concentrations at which imidacloprid may occur after initial migration is unknown. The presence and concentration of imidacloprid in three streams adjacent to recently treated hemlock (soil drench >10 m from stream channels) were assessed in the Big South Fork National River and Recreation Area. Two standard water grabs were collected monthly for 1 yr from a location downstream from imidacloprid-treated areas. Samples were analyzed using liquid chromatography tandem mass spectrometry (limit of detection = 0.025 µg L). Imidacloprid was detected in all treatment streams during a single rain event that occurred 184 to 196 d after treatments, and concentrations ranged from 0.053 to 0.833 µg L. Imidacloprid was not detected on any other sampling date from treatment streams. All observed positive detections exceeded the USEPA freshwater invertebrate chronic endpoint (0.01 µg L). One stream sample exceeded the USEPA freshwater invertebrate acute endpoint (0.39 µg L). However, previous macroinvertebrate community assessments in streams with similar concentrations did not indicate negative effects to aquatic fauna. These findings help characterize the risk of imidacloprid treatments to stream macroinvertebrates within 1 yr of soil applications.

The Benefits of Implementing an Early Mobility Protocol in Postoperative Neurosurgical Spine Patients.

: Background: Despite the known benefits of early postsurgical mobility, there are no clear recommendations on early mobility among uncomplicated postoperative neurosurgical spine patients. PURPOSE: The purpose of this quality improvement initiative was to establish an NP-led early mobility protocol to reduce uncomplicated postsurgical spine patients' length of stay (LOS) in the hospital and eliminate the variability of postsurgical care. A secondary objective was to educate and empower nursing staff to initiate the early mobility protocol independently and incorporate it in their practice to improve patient care. METHODS: Two neurosurgery NPs led an interprofessional team to develop the early mobility protocol. Team members provided preadmission preoperative education to communicate the necessity for early mobility and provide information about the protocol. New nursing guidelines called for patient mobility on the day of surgery, within six hours of arrival on the medical-surgical unit. Nurses were empowered to get patients out of bed independently, without a physical therapy consultation; they also removed urinary catheters and discontinued IV opioids when patients' status permitted. RESULTS: Over a one-year period, implementation of the protocol resulted in a nine-hour reduction in LOS per hospitalization in neurosurgical spine patients who underwent lumbar laminectomies. The protocol also allowed nurses more autonomy in patient care and was a catalyst for patient involvement in their postoperative mobility. Given the success of the protocol, it is being replicated by other surgical services throughout the organization. CONCLUSIONS: This low-cost, high-reward initiative aligns with the strategic plan of the organization and ensures that high-quality, patient-centered care remains the priority. NPs in other institutions can modify this protocol to promote postoperative mobility in their organizations.

Cervical laminoforaminotomy for radiculopathy: Symptomatic and functional outcomes in a large cohort with long-term follow-up.

BACKGROUND: The efficacy and safety of cervical laminoforaminotomy (FOR) in the treatment of cervical radiculopathy has been demonstrated in several series with follow-up less than a decade. However, there is little data analyzing the relative effectiveness of FOR for radiculopathy due to soft disc versus osteophyte disease. In the present study, we review our experience with FOR in a single-center cohort, with long-term follow-up. METHODS: We examined the charts of patients who underwent 1085 FORs between 1990 and 2009. A cohort of these patients participated in a telephone interview designed to assess improvement in symptoms and function. RESULTS: A total of 338 interviews were completed with a mean follow-up of 10 years. Approximately 90% of interviewees reported improved pain, weakness, or function following FOR. Ninety-three percent of patients were able to return to work after FOR. The overall complication rate was 3.3%, and the rate of recurrent radiculopathy requiring surgery was 6.2%. Soft disc subtypes compared to osteophyte disease by operative report were associated with improved symptoms (P < 0.05). The operative report of these pathologic subtypes was associated with the preoperative magnetic resonance imaging (MRI) interpretation (P < 0.001). CONCLUSIONS: These results suggest that FOR is a highly effective surgical treatment for cervical radiculopathy with a low incidence of complications. Radiculopathy due to soft disc subtypes may be associated with a better prognosis compared to osteophyte disease, although osteophyte disease remains an excellent indication for FOR.

Self-administered preoperative antiseptic wash to prevent postoperative infection after deep brain stimulation.

BACKGROUND: Prevention of surgical site infections is critical in deep brain stimulation (DBS). In the present study, we tested the ability of a self-administered preoperative alcohol-based (70% ethyl alcohol) preparation to reduce the rate of postoperative infection after DBS surgery. METHODS: This Institutional Review Board-approved retrospective review was conducted at our institution between January 2005 and October 2007 (mean follow-up, 23 months). The participants comprised a consecutive sample of 172 patients with movement disorders who underwent DBS surgery at our institution. Starting in January 2007, all patients were required to use the alcohol-based preparation. These patients (n = 48) were instructed to self-administer the wash on the night before surgery and the morning of surgery. Before this time, no self-administered wash was used (n = 122). RESULTS: There was no difference in preoperative skin cleansing between the 2 groups, and all patients received intravenous antibiotics immediately before and after surgery for 24 hours. We compared the rate of postoperative infection in the 2 groups and reviewed other possible factors underlying infection. We found 11 cases of infection (6.47%), all in the group without the preoperative antiseptic wash. The infection rate was 9.02% in the group without the preoperative wash and 0 in the group with the preoperative wash (P < .029). There was no difference between the 2 groups in terms of mean age, duration of operative procedure, or number of microelectrode tracts attempted. CONCLUSIONS: Our results support the incorporation of this self-administered antiseptic wash into our standard antiseptic protocol for patients undergoing DBS surgery.

Intracerebral microdialysis during deep brain stimulation surgery.

BACKGROUND: This report describes the use of microdialysis in conjunction with deep brain stimulation (DBS) surgery to assess extracellular levels of neurotransmitters within the human basal ganglia (BG). Electrical stimulation of the subthalamic nucleus (STN) is an efficacious treatment for advanced Parkinson's disease, yet the mechanisms of STN DBS remain poorly understood. Measurement of neurotransmitter levels within the BG may provide insight into mechanisms of DBS, but such an approach presents technical challenges. METHODS: After microelectrode recordings confirmed location of STN, a custom microdialysis guide cannula was inserted. A CMA (Stockholm, Sweden) microdialysis probe was then positioned to the same depth as the microrecording electrode in STN or 2mm inferiorly to record in the substantia nigra. The catheter was perfused at a rate of 2.0 microL/min with a sterile mock CSF solution and samples of extracellular fluid were collected at regular intervals. Dialysate samples were analyzed using high-pressure liquid chromatography (HPLC) detection procedures for quantitation of glutamate, gamma-aminobutyric acid (GABA), and dopamine. RESULTS: Levels of neurotransmitters were reliably identified in dialysate samples using HPLC. By monitoring concentrations of glutamate, GABA and dopamine, we were able to demonstrate what seemed to be a steady state baseline within approximately 30 min. CONCLUSION: Microdialysis during DBS surgery is a feasible method for assessing levels of glutamate, GABA and dopamine within the human BG. Obtaining a steady state baseline of neurotransmitter levels appears feasible, thus making future studies of intraoperative microdialysis during DBS meaningful.

Count data distributions and their zero-modified equivalents as a framework for modelling microbial data with a relatively high occurrence of zero counts.

In many cases, microbial data are characterised by a relatively high proportion of zero counts, as occurs with some hygiene indicators and pathogens, which complicates the statistical treatment under the assumption of log normality. The objective of this work was to introduce an alternative Poisson-based distribution framework capable of representing this kind of data without incurring loss of information. The negative binomial, and two zero-modified parameterizations of the Poisson and negative binomial distributions (zero-inflated and hurdle) were fitted to actual zero-inflated bacterial data consisting of total coliforms (n=590) and Escherichia coli (n=677) present on beef carcasses sampled from nine Irish abattoirs. Improvement over the simple Poisson was shown by the simple negative binomial (p=0.426 for chi(2) test for the coliforms data) due to the added heterogeneity parameter, although it slightly overestimated the zero counts and underestimated the first few positive counts for both data sets. Whereas, the zero-modified Poisson could not cope with the data over-dispersion in any of its parameterizations (p<0.001 for chi(2) tests), the parameterizations of the zero-modified negative binomial presented differences in fit due to approximation errors. While the zero-inflated negative binomial parameterization was apparently reduced to a negative binomial due to a non-convergence of the logit parameter estimate, the goodness of fit of the hurdle negative binomial parameterization indicated that for the data sets under evaluation (coliforms data with approximately 13% zero counts and E.coli data with approximately 42% zero counts), the zero-modified negative binomial distribution was comparable to the simpler negative binomial distribution. Thus, bacterial data consisting of a considerable number of zero counts can be appropriately represented by using such count distributions, and this work serves as the starting point for an alternative statistical treatment of this kind of data and stochastic risk assessment modelling.

Ventilator-associated pneumonia patients who do not reduce bacteria from the lungs have a worse prognosis.

The authors determined the significance of serial semi-quantitative bronchoalveolar lavage (BAL) culture results in patients undergoing therapy for ventilator-associated pneumonia. A total of 32 patients underwent at least 2 nonbronchoscopic BAL studies. Fourteen patients had methicillin-resistant Staphylococcus aureus (MRSA). Of these, 11 had more than 100 colony-forming units (cfu) of MRSA/mL of BAL from the follow-up BAL. Eighteen patients had an organism other than MRSA, and 7 of these patients had > 100 cfu of bacteria/mL of BAL from the follow-up BAL. Of the 18 patients with > 100 cfu of bacteria/mL of BAL at follow-up, 14 (79%) died, whereas only 5 of 14 (36%) patients who cleared their bacteria at follow-up died within 28 days. The inability to reduce the bacterial burden from the lower respiratory tract within the first few days of therapy for ventilator-associated pneumonia was associated with increased mortality.