Locating the ventral intermediate thalamic nucleus for deep brain stimulation surgery: analysis of a case series comparing CT and MR targeting

BACKGROUND

Deep brain stimulation (DBS) surgery targeting the ventral intermediate thalamic nucleus (Vim) has proven efficacy in the treatment of tremor.

AIMS

The primary aim is to investigate whether there is a statistically significant difference in patient outcomes when CT-guided targeting of the Vim is compared with MRI-guided targeting.

METHODS

This is a retrospective study concerning patients undergoing Vim-targeted DBS at the Department of Neurosurgery, Royal Victoria Infirmary in Newcastle (9th August 2012 to 4th January 2019). Fahn-Tolosa-Marin Tremor Scale (FTM TS) and EQ-5D scores were collected from patient notes. Statistical analysis was performed using IBM® SPSS® Statistics Version 24. Independent samples t-tests were used to compare means.

RESULTS

Independent samples t-test did not reveal a statistically significant difference between CT (n = 10; FTM TS mean = 65.40, SD = 11.40; EQ-5D mean = 39.50, SD = 17.87) and MR (n = 7; FTM TS mean = 60.57, SD = 7.50; EQ-5D mean = 32.14, SD = 9.94) groups in pre-surgery FTM TS (t(15) = 0.977, p = 0.344) and EQ-5D (t(15) = 0.982, p = 0.342) scores. No statistically significant difference between the CT (FTM TS mean = 24.12, SD = 20.47; EQ-5D mean = 75.56, SD = 15.63) and MR (FTM TS mean = 22.86, SD = 6.72; EQ-5D mean = 70.43, SD = 15.48) groups was revealed at 1 year assessment of FTM TS (t(14) = 0.155, p = 0.879) and EQ-5D (t(14) = 0.654, p = 0.524). The median difference between pre- and post-surgery FTM TS and EQ-5D scores in the CT group at 1 year was 43.00 and 35.00, respectively. The MR patient group median difference in pre- and post-surgery at 1 year was 35.00 and 35.00 respectively.

CONCLUSION

No statistically significant difference between CT and MR image-guided targeting patient groups was detected.

Patient selection and outcome of deep brain stimulation for multiple sclerosis-associated tremor

INTRODUCTION

Tremor is a disabling symptom of multiple sclerosis (MS), with limited treatment modalities. Thalamic ventral-intermediate-nucleus (VIM) deep brain stimulation (DBS) is a method of neuromodulation. We describe the long-term outcomes of our carefully selected patients who underwent VIM DBS for their MS-associated tremor.

METHODS

Patients were referred from the regional neurology units. Pre-operative assessments included suitability for anesthesia, tremor quantification by the Fahn-Tolosa-Marin scores, and quality-of-life (EQ5D) measures. Exclusion criteria included prominent cerebellar symptoms such as ataxia and dysmetria, intracranial pathology such as ventriculomegaly, cerebellar plaques and thalamic abnormality, and comorbid psychiatric symptoms. Seven patients (3M:4F) underwent DBS for MS-associated tremor between September 2013 and February 2019. Mean age was 42 years (±SD 8 years). DBS was performed at a mean of 13 years (±SD 9 years) after diagnosis of MS.

RESULTS

There were no postoperative surgical complications. All patients showed improvement in FTM tremor scores, by up to 61% at 6 months postoperatively. There was an improvement of 30-175% in quality-of-life scores at 6 months. Improvement of tremor and quality of life, over baseline, was sustained over a long period of follow-up (mean 26.6 months ± SD 20.7 months), including our longest duration at 72 months.

CONCLUSION

With careful selection, DBS is a safe, efficacious intervention for MS-tremor and can positively impact on tremor and quality of life, with effects over a long period. As patients live longer with MS and the advent of new therapies, DBS should be considered for selected patients.

DBS in tremor with dystonia: VIM, GPi or both? A review of the literature and considerations from a single-center experience

BACKGROUND

Deep brain stimulation (DBS) is an established treatment for dystonia and tremor. However, there is no consensus about the best surgical targeting strategy in patients with concomitant tremor and dystonia. Both the thalamic ventral intermediate nucleus (VIM) and the globus pallidus pars interna (GPi) have been proposed as targets. Few cases using them together in a double-target approach have also been reported.

METHODS

We reviewed the literature on this topic, summarizing results of different target choices. Additionally, we retrospectively report a case series of nine patients with sporadic dystonia and severe tremor treated with a double-target strategy at our center. Outcome measures were the Burke-Fahn-Marsden Dystonia Rating Scale (BFM) and Eq-5d scale.

RESULTS

In published studies of patients with dystonia and tremor, VIM-DBS is highly effective on tremor but raise some concerns about dystonia's control, while GPi-DBS is more effective on dystonia but does not always relieve tremor. GPi + VIM-DBS shows good efficacy but is rarely reported and reserved for selected patients. In our patients, the double-target strategy obtained a significant and durable improvement in tremor, dystonia, and quality of life. Additionally, compared with a cohort of patients with tremor treated with VIM-DBS only, significantly lower frequency and intensity of VIM stimulation were required to control tremor.

CONCLUSION

Our findings and published evidence seem to support the double-targeting approach as a safe and effective option in selected patients with tremor-dominant dystonia. This strategy appears to provide a more extensive control of either dystonia or tremor and may have a potential for limiting stimulation-related side effects.

The AMPA receptor antagonist perampanel suppresses epileptic activity in human focal cortical dysplasia

Focal cortical dysplasia (FCD) is one of the most common malformations causing refractory epilepsy. Dysregulation of glutamatergic systems plays a critical role in the hyperexcitability of dysplastic neurons in FCD lesions. The pharmacoresistant nature of epilepsy associated with FCD may be due to a lack of well‐tolerated and precise antiepileptic drugs that can target glutamate receptors. Here, for the first time in human FCD brain slices, we show that the established, noncompetitive α‐amino‐3‐hydroxy‐5‐methyl‐4‐isoxazolepropionic acid (AMPA) receptor antagonist, perampanel has potent antiepileptic action. Moreover, we demonstrate that this effect is due to a reduction in burst firing behavior in human FCD microcircuits. These data support a potential role for the treatment of refractory epilepsy associated with FCD in human patients.

An in vivo model of postinflammatory hyperpigmentation and erythema: clinical, colorimetric and molecular characteristics

BACKGROUND

Postinflammatory hyperpigmentation (PIH) is a common, acquired pigmentary disorder of the skin associated with significant quality-of-life impairment, especially in individuals with skin of colour. Current treatment for PIH is limited, largely due to a poor understanding of disease pathogenesis and the lack of a representative disease model.

OBJECTIVES

This study is intended to further develop, update and validate our previously designed in vivo model of acne-induced PIH/postinflammatory erythema (PIE) using different concentrations of trichloroacetic acid (TCA), a medium-depth chemical peel.

METHODS

Twenty-nine patients with skin types II-VI and clinician-confirmed presence of two or more truncal acne pustules and PIH/PIE were included. On the basis of Investigator's Global Assessment (IGA), clinical polarized photography (CPP), colorimetry and Skindex, we experimentally determined an optimum TCA concentration and assessed our model's ability to exhibit a dose-response relationship between degree of inciting insult and severity of resulting pigmentation. We also performed differential microRNA profiling and pathway analysis to explore the potential of microRNAs as molecular adjuncts to our model.

RESULTS

Application of TCA 30% produced lesions indistinguishable from acne-induced PIH and PIE lesions on the basis of colorimetry data without causing epidermal necrosis. Application of progressively increasing TCA doses from 20% to 30% resulted in concentration-dependent increases in CPP, IGA and colorimetry scores at all timepoints during the study. miRNA-31 and miRNA-23b may play a role in PIH pathogenesis, although further validation is required.

CONCLUSIONS

Our TCA-based in vivo model, using TCA concentrations between 20% and 30% with an optimum of 30%, enables the quantitative assessment of the pigmentary response to varying degrees of cutaneous inflammation in a fashion that mirrors natural acne-induced PIH and PIE.

532 CARING FOR AND CARING ABOUT OLDER PEOPLE LIVING WITH SEVERE FRAILTY DURING COVID-19

Introduction

An ongoing study collected survey and interview data from older people with frailty living in the community near end-of-life during the Covid-19 pandemic.

Methods

Unstructured interviews with older people with frailty living in the community (N = 10), which included accounts from unpaid carers (N = 5), were video and audio recorded between October–November 2021. Six of these older people have died since fieldwork completion. A face-to-face survey collected data from a further 10 older people. Participants ages ranged from 70–99, 11, men, and 9 women, living in owned, rented, or sheltered accommodation, with Clinical Frailty Scores of 6 (N = 8), 7 (N = 9), and 8 (N = 3).

Results

Topics raised in relation to the pandemic included loss of social contact and increased loneliness, concern about not physically getting out, and losing physical function. Older people struggled to gain access to health and social care for support and previously received services were withdrawn. Most participants did not have access to internet and relied heavily on families to facilitate virtual contact with health professionals. Families and friends were the main anchor in facilitating social and health care including chasing up medications, liaising with social care to ensure quality and consistency of care provided, and monitoring older people’s health. Where older people’s conditions worsened family provided intense support, though family carers described the strain and unsustainability of this provision. Older people and their families felt they had been forgotten.

Conclusions

These are insights from hard-to-reach population that are frequently invisible. Greater examination of the impact of using communication technologies in care provision on those with poor access to and capabilities with using these technologies is required. Unpaid carers need more information and resources to support the care they provide and to facilitate access to appropriate social and health care services for those they care for.

CSF Rhinorrhea After Endonasal Intervention to the Skull Base (CRANIAL) - Part 2: Impact of COVID-19

BACKGROUND

During the coronavirus disease 2019 (COVID-19) pandemic, concerns have been raised regarding the increased risk of perioperative mortality for patients with COVID-19, and the transmission risk to healthcare workers, especially during endonasal neurosurgical operations. The Pituitary Society has produced recommendations to guide management during this era. We sought to assess contemporary neurosurgical practice and the effects of COVID-19.

METHODS

A multicenter prospective observational cohort study was conducted at 12 tertiary neurosurgical units (United Kingdom and Ireland). Data were collected from March 23 to July 31, 2020, inclusive. The data points collected included patient demographics, preoperative COVID-19 test results, operative modifications, and 30-day COVID-19 infection rates.

RESULTS

A total of 124 patients were included. Of the 124 patients, 116 (94%) had undergone COVID-19 testing preoperatively (transsphenoidal approach, 97 of 105 [92%]; expanded endoscopic endonasal approach, 19 of 19 [100%]). One patient (1 of 116 [0.9%]) had tested positive for COVID-19 preoperatively, requiring a delay in surgery until the infection had been confirmed as resolved. Other than transient diabetes insipidus, no other complications were reported for this patient. All operating room staff had worn at least level 2 personal protective equipment. Adaptations to surgical techniques included minimizing drilling, draping modifications, and the use of a nasal iodine wash. At 30 days postoperatively, no evidence of COVID-19 infection (symptoms or positive formal testing results) were found in our cohort and no mortality had occurred.

CONCLUSIONS

Preoperative screening protocols and operative modifications have facilitated endonasal neurosurgery during the COVID-19 pandemic, with the Pituitary Society guidelines followed for most of these operations. We found no evidence of COVID-19 infection in our cohort and no mortality, supporting the use of risk mitigation strategies to continue endonasal neurosurgery in subsequent pandemic waves.

17 Conversations on Living and Dying: Facilitating Advance Care Planning for Older People Living with Frailty. A Qualitative Study

Introduction

Advance care planning (ACP) is a process that supports people to articulate their future care preferences. This process is a priority for older people living with frailty due to their vulnerability to sudden deterioration, something that has been highlighted during the current pandemic. However, ACP is uncommon for older people living with frailty, hindering choice and person-centred end-of-life care. This study aimed to identify the barriers, facilitators and behaviours required to support cognitively-able, community-dwelling older people living with frailty to engage with ACP. Findings will inform the development an ACP intervention underpinned by behavioural change theory.

Methods

Semi-structured interviews with community-dwelling older people living with frailty (Clinical Frailty Score 6 or 7) and family members were audio-recorded, filmed and transcribed verbatim. A thematic analysis framework was developed using a recent systematic review, and expanded to reflect new themes.

Results

Ten older people living with frailty and eight family members were interviewed. The older people’s median age was 85 and seven were female. Family members were spouses (n = 4) and children (n = 4). The key findings were that: the meaning of ACP could be unclear and at times confusing; many of the older people believed ACP was not relevant to them; relationships and relational autonomy were of greater relevance to older people than autonomous decision-making; older people were more interested in living well now than in planning for the future.

Conclusions

Older people living with frailty need to be engaged with ACP in a way that helps them to understand what ACP is and why it is relevant for them. Professionals need to develop their skills in assessing readiness and facilitating ACP conversations with this population at the older person’s pace. Reframing ACP to include living well now alongside encouraging family inclusion would also relate better to this populations’ lives.

The stability of care preferences following acute illness: a mixed methods prospective cohort study of frail older people

Background

Patient preferences are integral to person-centred care, but preference stability is poorly understood in older people, who may experience fluctuant illness trajectories with episodes of acute illness. We aimed to describe, and explore influences on the stability of care preferences in frail older people following recent acute illness.

Methods

Mixed-methods prospective cohort study with dominant qualitative component, parallel data collection and six-month follow up. Study population: age ≥ 65, Rockwood Clinical Frailty score ≥ 5, recent acute illness requiring acute assessment/hospitalisation. Participants rated the importance of six preferences (to extend life, improve quality of life, remain independent, be comfortable, support ‘those close to me’, and stay out of hospital) at baseline, 12 and 24 weeks using a 0–4 scale, and ranked the most important. A maximum-variation sub-sample additionally contributed serial in-depth qualitative interviews. We described preference stability using frequencies and proportions, and undertook thematic analysis to explore influences on preference stability.

Results

90/192 (45%) of potential participants consented. 82/90 (91%) answered the baseline questionnaire; median age 84, 63% female. Seventeen undertook qualitative interviews. Most participants consistently rated five of the six preferences as important (range 68–89%). ‘Extend life’ was rated important by fewer participants (32–43%). Importance ratings were stable in 61–86% of cases. The preference ranked most important was unstable in 82% of participants.

Preference stability was supported by five influences: the presence of family support; both positive or negative care experiences; preferences being concordant with underlying values; where there was slowness of recovery from illness; and when preferences linked to long term goals. Preference change was related to changes in health awareness, or life events; if preferences were specific to a particular context, or multiple concurrent preferences existed, these were also more liable to change.

Conclusions

Preferences were largely stable following acute illness. Stability was reinforced by care experiences and the presence of family support. Where preferences were unstable, this usually related to changing health awareness. Consideration of these influences during preference elicitation or advance care planning will support delivery of responsive care to meet preferences. Obtaining longer-term data across diverse ethnic groups is needed in future research.

CSF rhinorrhoea after endonasal intervention to the anterior skull base (CRANIAL): proposal for a prospective multicentre observational cohort study

BACKGROUND

The endonasal transsphenoidal approach (TSA) has emerged as the preferred approach in order to treat pituitary adenoma and related sellar pathologies. The recently adopted expanded endonasal approach (EEA) has improved access to the ventral skull base whilst retaining the principles of minimally invasive surgery. Despite the advantages these approaches offer, cerebrospinal fluid (CSF) rhinorrhoea remains a common complication. There is currently a lack of comparative evidence to guide the best choice of skull base reconstruction, resulting in considerable heterogeneity of current practice. This study aims to determine: (1) the scope of the methods of skull base repair; and (2) the corresponding rates of postoperative CSF rhinorrhoea in contemporary neurosurgical practice in the UK and Ireland.

METHODS

We will adopt a multicentre, prospective, observational cohort design. All neurosurgical units in the UK and Ireland performing the relevant surgeries (TSA and EEA) will be eligible to participate. Eligible cases will be prospectively recruited over 6 months with 6 months of postoperative follow-up. Data points collected will include: demographics, tumour characteristics, operative data), and postoperative outcomes. Primary outcomes include skull base repair technique and CSF rhinorrhoea (biochemically confirmed and/or requiring intervention) rates. Pooled data will be analysed using descriptive statistics. All skull base repair methods used and CSF leak rates for TSA and EEA will be compared against rates listed in the literature.

ETHICS AND DISSEMINATION

Formal institutional ethical board review was not required owing to the nature of the study - this was confirmed with the Health Research Authority, UK.

CONCLUSIONS

The need for this multicentre, prospective, observational study is highlighted by the relative paucity of literature and the resultant lack of consensus on the topic. It is hoped that the results will give insight into contemporary practice in the UK and Ireland and will inform future studies.

The role of astrocytes in seizure generation: insights from a novel in vitro seizure model based on mitochondrial dysfunction

Approximately one-quarter of patients with mitochondrial disease experience epilepsy. Their epilepsy is often severe and resistant towards conventional antiepileptic drugs. Despite the severity of this epilepsy, there are currently no animal models available to provide a mechanistic understanding of mitochondrial epilepsy. We conducted neuropathological studies on patients with mitochondrial epilepsy and found the involvement of the astrocytic compartment. As a proof of concept, we developed a novel brain slice model of mitochondrial epilepsy by the application of an astrocytic-specific aconitase inhibitor, fluorocitrate, concomitant with mitochondrial respiratory inhibitors, rotenone and potassium cyanide. The model was robust and exhibited both face and predictive validity. We then used the model to assess the role that astrocytes play in seizure generation and demonstrated the involvement of the GABA-glutamate-glutamine cycle. Notably, glutamine appears to be an important intermediary molecule between the neuronal and astrocytic compartment in the regulation of GABAergic inhibitory tone. Finally, we found that a deficiency in glutamine synthetase is an important pathogenic process for seizure generation in both the brain slice model and the human neuropathological study. Our study describes the first model for mitochondrial epilepsy and provides a mechanistic insight into how astrocytes drive seizure generation in mitochondrial epilepsy.

Multiple-aetiology enteric infections involving non-O157 Shiga toxin-producing Escherichia coli--FoodNet, 2001-2010

We describe multiple-aetiology infections involving non-O157 Shiga toxin-producing Escherichia coli (STEC) identified through laboratory-based surveillance in nine FoodNet sites from 2001 to 2010. A multiple-aetiology infection (MEI) was defined as isolation of non-O157 STEC and laboratory evidence of any of the other nine pathogens under surveillance or isolation of >1 non-O157 STEC serogroup from the same person within a 7-day period. We compared exposures of patients with MEI during 2001-2010 with those of patients with single-aetiology non-O157 STEC infections (SEI) during 2008-2009 and with those of the FoodNet population from a survey conducted during 2006-2007. In total, 1870 non-O157 STEC infections were reported; 68 (3.6%) were MEI; 60 included pathogens other than non-O157 STEC; and eight involved >1 serogroup of non-O157 STEC. Of the 68 MEI, 21 (31%) were part of six outbreaks. STEC O111 was isolated in 44% of all MEI. Of patients with MEI, 50% had contact with farm animals compared with 29% (P < 0.01) of persons with SEI; this difference was driven by infections involving STEC O111. More patients with non-outbreak-associated MEI reported drinking well water (62%) than respondents in a population survey (19%) (P < 0.01). Drinking well water and having contact with animals may be important exposures for MEI, especially those involving STEC O111.

Gap junction networks can generate both ripple-like and fast ripple-like oscillations

Fast ripples (FRs) are network oscillations, defined variously as having frequencies of > 150 to > 250 Hz, with a controversial mechanism. FRs appear to indicate a propensity of cortical tissue to originate seizures. Here, we demonstrate field oscillations, at up to 400 Hz, in spontaneously epileptic human cortical tissue in vitro, and present a network model that could explain FRs themselves, and their relation to 'ordinary' (slower) ripples. We performed network simulations with model pyramidal neurons, having axons electrically coupled. Ripples (< 250 Hz) were favored when conduction of action potentials, axon to axon, was reliable. Whereas ripple population activity was periodic, firing of individual axons varied in relative phase. A switch from ripples to FRs took place when an ectopic spike occurred in a cell coupled to another cell, itself multiply coupled to others. Propagation could then start in one direction only, a condition suitable for re-entry. The resulting oscillations were > 250 Hz, were sustained or interrupted, and had little jitter in the firing of individual axons. The form of model FR was similar to spontaneously occurring FRs in excised human epileptic tissue. In vitro, FRs were suppressed by a gap junction blocker. Our data suggest that a given network can produce ripples, FRs, or both, via gap junctions, and that FRs are favored by clusters of axonal gap junctions. If axonal gap junctions indeed occur in epileptic tissue, and are mediated by connexin 26 (recently shown to mediate coupling between immature neocortical pyramidal cells), then this prediction is testable.

Observation of a charged charmoniumlike structure in e+ e- → π+ π- J/ψ at sqrt[s] = 4.26 GeV

We study the process ee+ e- → π+ π- J/ψ at a center-of-mass energy of 4.260 GeV using a 525  pb(-1) data sample collected with the BESIII detector operating at the Beijing Electron Positron Collider. The Born cross section is measured to be (62.9±1.9±3.7)  pb, consistent with the production of the Y(4260). We observe a structure at around 3.9  GeV/c2 in the π(±)J/ψ mass spectrum, which we refer to as the Z(c)(3900). If interpreted as a new particle, it is unusual in that it carries an electric charge and couples to charmonium. A fit to the π(±)J/ψ invariant mass spectrum, neglecting interference, results in a mass of (3899.0±3.6±4.9)  MeV/c2 and a width of (46±10±20)  MeV. Its production ratio is measured to be R = (σ(e+ e- → π(±)Z(c)(3900)(∓) → π+ π- J/ψ)/σ(e+ e- → π+ π- J/ψ)) = (21.5±3.3±7.5)%. In all measurements the first errors are statistical and the second are systematic.

Observation of two new N* resonances in the decay ψ(3686)→ppπ0

Based on 106×10(6)ψ(3686) events collected with the BESIII detector at the BEPCII facility, a partial wave analysis of ψ(3686)→ppπ0 is performed. The branching fraction of this channel has been determined to be B(ψ(3686)→ppπ0)=(1.65±0.03±0.15)×10(-4). In this decay, 7 N* intermediate resonances are observed. Among these, two new resonances, N(2300) and N(2570) are significant, one 1/2+ resonance with a mass of 2300(-30-0)(+40+109)  MeV/c2 and width of 340(-30-58)(+30+110)  MeV/c2, and one 5/2- resonance with a mass of 2570(-10-10)(+19+34)  MeV/c2 and width of 250(-24-21)(+14+69)  MeV/c2. For the remaining 5 N* intermediate resonances [N(1440), N(1520), N(1535), N(1650) and N(1720)], the analysis yields mass and width values that are consistent with those from established resonances.

Evidence for the direct two-photon transition from ψ(3686) to J/ψ

The two-photon transition ψ(3686)→γγJ/ψ is studied in a sample of 1.06×10(8) ψ(3686) decays collected by the BESIII detector. The branching fraction is measured to be (3.1±0.6(stat)(-1.0)(+0.8)(syst))×10(-4) using J/ψ→e(+)e(-) and J/ψ→μ(+)μ(-) decays, and its upper limit is estimated to be 4.5×10(-4) at the 90% confidence level. This work represents the first measurement of a two-photon transition among charmonium states. The orientation of the ψ(3686) decay plane and the J/ψ polarization in this decay are also studied. In addition, the product branching fractions of sequential E1 transitions ψ(3686)→γχ(cJ) and χ(cJ)→γJ/ψ(J=0,1,2) are reported.

Development and Validation of Computed Tomography Derived Anthropometric Regression Equations for Estimating Abdominal Adipose Tissue Distribution

The purpose of this study was twofold: (1) to develop multiple regression equations for predicting computed tomography (CT) derived intra-abdominal (IAF), subcutaneous (SCF), and total (TOTF= IAF+SCF) abdominal adipose tissue areas from anthropometric measures in adult white males with a large range of age (18-71 years) and percent body fat (2.0-40.6); and (2) to validate the new and existing equations that used similar Hounsfield Units (HU) for determining IAF for estimating these fat depots. One hundred fifty-one white male subjects had IAF, SCF, and TOTF determined by a single CT scan, skinfold and circumference measures taken and body density determined. Linear intra-correlations and factor analysis procedures were used to identify variables for inclusion in stepwise multiple regression solutions. IAF was estimated from age, waist circumference, the sum of mid-thigh and lower thigh circumferences, and vertical abdominal skinfold. SCF was estimated from age, umbilicus circumference, chest and suprailiac skinfolds. TOTF was estimated from age, body mass index (BMI), chest skinfold, and umbilicus circumference. R2 for IAF, SCF, and TOTF was .73, .77, and .86 respectively. The existing and the new equations were validated on an independent sub-sample of 51 subjects. The only existing equation that met validation criteria had a validation R2 = .67 for IAF. All three new equations met validation criteria with R2 validations of .75, .79, and .85 for IAF, SCF, and TOTF respectively. It is concluded that the new equations might be used as an inexpensive estimation of IAF, SCF, and TOTF in adult white males varying greatly in age and percent body fat.

A prospective pilot study of two-session Gamma Knife surgery for large metastatic brain tumors

The purpose of this prospective study is to evaluate the efficacy and limitations of two-session Gamma Knife radiosurgery (GKS) alone for large metastatic brain tumors. Inclusion criteria were as follows: (i) patients with large metastatic brain tumors (volume >15 cm(3) in the supratentorial region or >10 cm(3) in the infratentorial region), and (ii) tumors not causing clinical signs of impending cerebral herniation. Twenty-eight lesions in 27 consecutive patients (18 men and 9 women, age range 32 to 88 years, median age 65 years) were included in this study. The radiosurgical protocol was as follows: 20-30 Gy given in two fractions 3-4 weeks apart. The local tumor control rate and the overall survival rate were calculated by using the Kaplan-Meier method. Median tumor volumes were 17.8 cm(3) at first GKS and 9.7 cm(3) at second GKS. Median follow-up time was 8.9 months. The local control rate was 85 % at 6 months and 61 % at 12 months. The overall survival rate after GKS was 63 % at 6 months and 45 % at 12 months. The 1-year rate of prevention of neurological death was maintained at 78 %. Mean Karnofsky performance status (KPS) improved from 61 [95 % confidence interval (CI), 57-71] at first GKS to 80 (95 % CI, 74-85) at second GKS; the best follow-up mean KPS was 85 (95 % CI, 78-91) (p < 0.001). Local tumor recurrence necessitated craniotomy in two patients and repeat GKS in three patients. Seventeen patients died, and the causes of death were as follows: 3 from local progression, 2 from meningeal carcinomatosis, and 12 from progression of the primary tumor. Delayed symptomatic perilesional edema developed in one patient and eventually resolved with conservative treatment. Two-session GKS for large brain metastases appears to be an effective treatment in terms of both local tumor control and neurological palliation with minimal treatment-related morbidity. These data suggest that two-session GKS could be used as an alternative to surgical resection of large tumors in patients with significant comorbidity and/or at an advanced age. The optimum regimen for dose and fraction schedule remains to be established.

First observation of the M1 transition ψ(3686)→γη(c)(2S)

Using a sample of 106×10(6) ψ(3686) events collected with the BESIII detector at the BEPCII storage ring, we have made the first measurement of the M1 transition between the radially excited charmonium S-wave spin-triplet and the radially excited S-wave spin-singlet states: ψ(3686)→γη(c)(2S). Analyses of the processes ψ(3686)→γη(c)(2S) with η(c)(2S)→K(S)(0)K(±)π(∓) and K(+)K(-)π(0) give an η(c)(2S) signal with a statistical significance of greater than 10 standard deviations under a wide range of assumptions about the signal and background properties. The data are used to obtain measurements of the η(c)(2S) mass (M(η(c)(2S))=3637.6±2.9(stat)±1.6(syst) MeV/c(2)), width (Γ(η(c)(2S))=16.9±6.4(stat)±4.8(syst) MeV), and the product branching-fraction (B(ψ(3686)→γη(c)(2S))×B(η(c)(2S)→KKπ)=(1.30±0.20(stat)±0.30(syst))×10(-5)). Combining our result with a BABAR measurement of B(η(c)(2S)→KKπ), we find the branching fraction of the M1 transition to be B(ψ(3686)→γη(c)(2S))=(6.8±1.1(stat)±4.5(syst))×10(-4).

Glissandi: transient fast electrocorticographic oscillations of steadily increasing frequency, explained by temporally increasing gap junction conductance

PURPOSE

We describe a form of very fast oscillation (VFO) in patient electrocorticography (ECoG) recordings, that can occur prior to ictal events, in which the frequency increases steadily from ≈ 30-40 to >120 Hz, over a period of seconds. We dub these events "glissandi" and describe a possible model for them.

METHODS

Four patients with epilepsy had presurgical evaluations (with ECoG obtained in two of them), and excised tissue was studied in vitro, from three of the patients. Glissandi were seen spontaneously in vitro, associated with ictal events-using acute slices of rat neocortex-and they were simulated using a network model of 15,000 detailed layer V pyramidal neurons, coupled by gap junctions.

KEY FINDINGS

Glissandi were observed to arise from human temporal neocortex. In vitro, they lasted 0.2-4.1 s, prior to ictal onset. Similar events were observed in the rat in vitro in layer V of frontal neocortex when alkaline solution was pressure-ejected; glissandi persisted when γ-aminobutyric acid A (GABA(A)), GABA(B), and N-methyl-d-aspartate (NMDA), and alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors were blocked. Nonalkaline conditions prevented glissando generation. In network simulations it was found that steadily increasing gap junction conductance would lead to the observed steady increase in VFO field frequency. This occurred because increasing gap junction conductance shortened the time required for an action potential to cross from cell to cell.

SIGNIFICANCE

The in vitro and modeling data are consistent with the hypothesis that glissandi arise when pyramidal cell gap junction conductances rise over time, possibly as a result of an alkaline fluctuation in brain pH.

Unplanned reoperation rates in pediatric neurosurgery: a single center experience and proposed use as a quality indicator

OBJECT

The pediatric neurosurgery practice over 2 years was reviewed at a tertiary neurosciences center. The intention was to establish the frequency of unplanned reoperations at the center, investigate the factors responsible, and consider using unplanned reoperations as a quality indicator.

METHODS

All pediatric neurosurgical operations done between January 2008 and January 2010 were reviewed using data from operation theater logs and hospital records. Data were recorded as per the standard requirements of the Society of British Neurological Surgeons for incorporation into the national database. "Unplanned reoperation" was defined as any unscheduled secondary procedure required for a complication resulting directly or indirectly from the index operation or as an unscheduled return to the operating theater for the same condition. Operations were defined as "urgent" if they had to be performed out of hours (that is, outside the hours of 8:00 a.m. to 5:00 p.m.), "emergency elective" if they were included on the emergency list but within working hours, and "routine elective" if they were on the scheduled operations list. Both overall and 30-day unplanned reoperation rates were considered. Factors influencing unplanned reoperations were explored using a logistic regression model.

RESULTS

Four hundred ten operations were analyzed. The overall unplanned reoperation rate was 28%. The median time to an unplanned reoperation was 9 days. Risk factors for unplanned reoperations included a CSF diversion procedure (OR 7, p < 0.0001) and an urgent procedure (OR 2.5, p = 0.02, higher unplanned reoperations for urgent procedures relative to routine electives). The 30-day unplanned reoperation rate was 17%. Urgent cases composed 32% of all operations. Trainees performed 52% of the urgent operations. Forty-four percent of all operations were related to CSF diversion. Sixty-four percent of patients had reoperations during the course of the study period, and 44% of these reoperations were unplanned.

CONCLUSIONS

An unplanned return to the operation theater is common in the authors' pediatric neurosurgical practice and is procedure specific. Unplanned reoperation rates may be useful for monitoring quality across hospitals and identifying opportunities for quality improvement. The authors propose the use of this index as a quality indicator and advocate its validation in a prospective multicenter study.

Congenital glioblastoma multiforme: complete resection with long-term survival and a novel technique of contralateral cystoventriculostomy

Congenital glioblastomas are rare primary tumours of the central nervous system with poor prognosis if left untreated. We report the case of a 4-week-old infant with such a tumour treated by surgical excision and a course of postoperative chemotherapy. After the chemotherapy, the patient displayed a neurological deterioration and follow-up magnetic resonance imaging (MRI) scans revealed no signs of recurrence, but showed entrapment and significant distension of the right lateral ventricle. A novel technique of contralateral cystoventriculostomy was performed to attempt to decompress the cyst and improve the infant's neurological status. After surgery there was a significant neurological improvement, and 30 months after resection the child is alive, with mild hemiparesis and no signs of recurrence on follow-up MRI scan. The cystoventriculostomy is patent and continues to decompress the encapsulated ventricle.

Tethering of the cervico-medullary junction with central cord oedema after foramen magnum decompression for Chiari malformation

An unusual complication following foramen magnum decompression for Chiari malformation is described: adhesive tethering of the cervico-medullary junction with oedema of the upper spinal cord and lower medulla. Further surgery was required to correct this condition.

Factors predicting improvement in primary generalized dystonia treated by pallidal deep brain stimulation

Despite the beneficial effects of Globus Pallidus internus (GPi) deep brain stimulation (DBS) in patients with primary generalized dystonia (PGD), the degree of improvement varies from one patient to another. The objective of this study was to examine the effects of clinical, anatomical (volume of the GPi), and electrical variables on the postoperative Burke-Fahn-Marsden Dystonia rating scale (BFMDRS) motor score to identify which factors may be predictive of the degree of improvement. We reviewed retrospectively the clinical records of 40 steady-state patients with PGD who had been treated by bilateral GPi lead implantation. The follow-up period was 2 to 8 years. The correlation between the electrical parameters (voltage, impedance, and current) and the clinical outcome was studied. An analysis of covariance was performed to identify factors predictive of the magnitude of improvement. The most influential factors according to the model are as follows: the preoperative BFMDRS score (P < 0.0001); age at surgery (P < 0.0001); the right GPi volume (P = 0.002); the left stimulated GPi volume (P = 0.005). No significant correlation was found between the electrical parameters used and the mean motor scores in steady state.

Contesting targets as a measurement of success in agricultural extension: a case study of the Grain & Graze Change-on-farm strategy

Grain & Graze was a mixed-farming systems program conducted across nine regions of Australia over 2003–08. It had a goal of ensuring adoption of recommended practices on 6800 farms within the 5-year life of the program. This extension-based success target was further reflected in adoption targets set in contracts for each of the nine regions, and embedded into the program’s extension initiative, the Change-on-farm strategy. By 2008, the program had achieved adoption on 3200 farms. While less than half the target, this was considered by many a remarkable achievement, raising questions about the efficacy of adoption targets as a measurement of success. In a program based on devolution, regional delivery and local empowerment, the targets were contested between participants on other grounds. This paper explores how the targets were set, what Change-on-farm supported, what it achieved and how its success related to adoption targets. Using the Grain & Graze program as a case study, the paper concludes that the notion of targets as a motivator of success rather than as a measure of success is pertinent in complex systems-based research and development. The authors do not advocate avoiding targets, but suggest that both targets and the evaluation process by which success is measured be mutually negotiated in the true spirit of participatory process.

Trans-Sylvian selective amygdalohippocampectomy for medically intractable temporal lobe epilepsy: a single-centre experience

Selective amygdalohippocampectomy (SelAH) is now widely used in the surgical treatment of patients with medically intractable medial temporal lobe epilepsy (MTLE). We present our single-centre experience of a uniform series of drug-resistant MTLE patients treated exclusively with SelAH. A retrospective study of 50 adult patients (25 males, 25 females, mean age 34 years) suffering from medically intractable MTLE was conducted. All patients has been investigated under the same protocol and operated by SelAH performed by one surgeon. Immediate and long-term follow-up was also available and is presented. Forty-two patients (84%) became seizure free (Engel's I); eight of them (16%) were classified as Engel's II; four (8%) as Engel's III; and one as Engel's IV (2%). In 42 of them the final result has been achieved after a single operation, while in the rest eight after a second or third surgical procedure. The mean follow-up period was 6.2 years. Two permanent complications (4%) with no treatment-related mortality have been detected. SelAH performed in well selected cases, where concordance between electrophysiological and MR findings exists, can be a safe and effective surgical treatment method for medically intractable MTLE.

Cardiovascular disease in women

This article provides an overview of cardiovascular disease (CVD) in women. It considers cardiovascular risk, investigations and treatment. Gender bias, controversies and current debates are highlighted. Issues concerned with access to cardiac health care, equality and public policy are also considered. The author concludes that CVD in women is under-recognised, often by women themselves, and therefore raising the profile of this disease in women should be a health priority.

Intra-abdominal adipose tissue values associated with risk of possessing elevated blood lipids and blood pressure

Central fat distribution and more recently intra-abdominal adipose tissue (IAF) have been associated with elevated cardiovascular risk factors (CRF). Despite increased interest in use of LAF for screening for CRF, interpretation of risk found in a specific IAF is difficult since regressions for estimating CRF from IAF have not been published. The purpose of this paper is to report IAF values that are likely to be associated with elevated CRF. One hundred forty-six healthy male subjects 30-71 years were evaluated for IAF and subcutaneous fat (computed tomography scan at 4th lumbar vertebra), height, body weight, % fat, various anthropometric measures, blood cholesterol (CHOL), HDL cholesterol (HDL), systolic blood pressure (SBP), and diastolic blood pressure (DBP). Receiver-Operating-Characteristic curves (ROC) were used to develop IAF cutpoints associated with elevation of at least one established CRF criteria (CHOL=200, HDL=<35, SBP=140, DBP=90). A sensitivity/(1- specificity) curve established the value of using IAF cutpoints for detecting elevated CRF. Likelihood ratios were used to identify optimal cutpoints. Two cutpoints were identified, 131 cm2 with a relatively high Lpos ratio and 71 cm2 with a relatively low Lneg. False positives associated with 131 cm2 were 14% for one or more elevated CRF. False negatives associated with 71 cm2 were 9% for one or more elevated CRF, 4% for two or more CRF, and 0% for three or more elevated CRF. This study clearly indicates that IAF above 131 cm2 is related to elevated CRF and IAF below 71 cm2 is associated with reduced cardiovascular risk.