ORCID Profile
0000-0002-8216-9410
Current Organisations
CSIRO
,
Philipps-Universität Marburg
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Publisher: BMJ
Date: 11-09-2021
Abstract: The effects of subthalamic stimulation (subthalamic nucleus-deep brain stimulation, STN-DBS) on impulsive and compulsive behaviours (ICB) in Parkinson’s disease (PD) are understudied. To investigate clinical predictors of STN-DBS effects on ICB. In this prospective, open-label, multicentre study in patients with PD undergoing bilateral STN-DBS, we assessed patients preoperatively and at 6-month follow-up postoperatively. Clinical scales included the Questionnaire for Impulsive-Compulsive Disorders in PD-Rating Scale (QUIP-RS), PD Questionnaire-8, Non-Motor Symptom Scale (NMSS), Unified PD Rating Scale in addition to levodopa-equivalent daily dose total (LEDD-total) and dopamine agonists (LEDD-DA). Changes at follow-up were analysed with Wilcoxon signed-rank test and corrected for multiple comparisons (Bonferroni method). We explored predictors of QUIP-RS changes using correlations and linear regressions. Finally, we dichotomised patients into ‘QUIP-RS improvement or worsening’ and analysed between-group differences. We included 55 patients aged 61.7 years±8.4 with 9.8 years±4.6 PD duration. QUIP-RS cut-offs and psychiatric assessments identified patients with preoperative ICB. In patients with ICB, QUIP-RS improved significantly. However, we observed considerable interin idual variability of clinically relevant QUIP-RS outcomes as 27.3% experienced worsening and 29.1% an improvement. In post hoc analyses, higher baseline QUIP-RS and lower baseline LEDD-DA were associated with greater QUIP-RS improvements. Additionally, the ‘QUIP-RS worsening’ group had more severe baseline impairment in the NMSS attention/memory domain. Our results show favourable ICB outcomes in patients with higher preoperative ICB severity and lower preoperative DA doses, and worse outcomes in patients with more severe baseline attention/memory deficits. These findings emphasise the need for comprehensive non-motor and motor symptoms assessments in patients undergoing STN-DBS. DRKS00006735.
Publisher: Cold Spring Harbor Laboratory
Date: 25-04-2023
DOI: 10.1101/2023.04.25.23289088
Abstract: Deep brain stimulation of the subthalamic nucleus (STN-DBS) is an effective treatment for motor and non-motor symptoms in advanced Parkinson’s disease (PD). However, considerable interin idual variability of outcomes exists. Neuroimaging based biomarkers, such as neurite orientation dispersion and density imaging (NODDI), a biophysical model based MRI-technique, have been proposed to predict clinical outcomes and therefore inform preoperative patient counselling. To detect microstructural properties of brain areas associated with short-term non-motor outcomes following STN-DBS in PD. In this prospective open-label study, 37 PD patients underwent diffusion MRI and comprehensive clinical assessments at preoperative baseline and 6-month follow-up. Neurite density index (NDI), orientation dispersion index (ODI), and fractional anisotropy (FA) were derived. Whole brain voxel-wise analysis assessed associations between microstructural metrics and non-motor outcomes corrected for multiple comparisons using a permutation-based approach. Intact microstructure within specific areas including right insular cortex, right putamen, right cingulum, and bilateral corticospinal tract were associated with greater postoperative improvement of non-motor symptom burden. Furthermore, microstructural properties of distinct brain regions were associated with postoperative changes in sleep, attention/memory, and urinary symptoms. Microstructural properties of distinct brain areas predict non-motor outcomes in DBS for PD. Therefore, diffusion MRI can support preoperative patient counselling and treatment selection by identifying patients with above-or below-average non-motor responses.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 03-2009
Publisher: CSIRO
Date: 2022
DOI: 10.25919/QBEQ-7955
Publisher: Springer Science and Business Media LLC
Date: 27-09-2011
DOI: 10.1007/S10143-011-0352-3
Abstract: Detailed outcome data for the management of anterior skull base fractures associated with cerebrospinal fluid (CSF) leakage is lacking. We present detailed follow-up data of a single-center study using a predetermined algorithm for the management of CSF leakage secondary to traumatic fractures. A number of 138 consecutive patients were included in the analysis all patients underwent high-resolution computed tomography (CT) scanning at time of admission with β(2)-transferrin testing used to confirm CSF leakage. Patients with acute surgical indications were operated as emergent leaks were repaired at the time of initial surgery in patients with intracranial pressure < 15 cm H(2)O. The remainder of the study population was managed conservatively including use of prophylactic antibiotics lumbar drainage (LD) catheters were placed in those patients with leakage persisting beyond 48 h. Leaks lasting longer than 5 days underwent microsurgical repair using an intradural bicoronal approach. One-year follow-up assessment included evaluation of neurological status, Glasgow Outcome Scale (GOS), and repeat head CT. Twenty eight patients (26.9%) underwent emergent surgery, 15 of whom had simultaneous CSF leak repair, whereas 76 patients (73.1%) underwent delayed CSF leak repair between days 5 and 14. Postoperative meningitis rate was low (1.9%). Postoperative CSF leak (1.9%) was managed by intradural or transnasal endoscopic operation. Comparable rates of anosmia and frontal lobe hypodensities were seen in the surgical and conservatively managed subgroups. The presented algorithm, utilizing prophylactic antibiotics, trial of LD, acute and/or delayed intradural microsurgery, yields favorable outcomes. Large randomized controlled trials are needed to better define the role of prophylactic antibiotics and to better characterize the optimal timing and approach of surgical repair.
Publisher: Frontiers Media SA
Date: 16-06-2021
DOI: 10.3389/FMARS.2021.686065
Abstract: The Torres Strait tropical rock lobster Panulirus ornatus (TRL) fishery is of immense social, cultural and economic importance to the region’s Indigenous fishers from both Australia and Papua New Guinea (PNG). During 2020, the COVID-19 pandemic indirectly impacted this fishery as well as a number of other fisheries reliant on international export markets. The TRL fishery is managed using an empirical (data-based) Harvest Control Rule (eHCR) to rapidly provide a recommended biological catch (RBC), based on catch, fishery-independent survey indices and catch-per-unit-effort (CPUE). Here, we summarize the impacts of COVID-19 on each of these critical data inputs and discuss whether the eHCR was considered adequately resilient to this unprecedented disruption to the system. Next, we use a quantitative supply chain index to analyze the impact of disruptions to the supply chain, and inform on potential adaptation strategies. The catch and CPUE data were impacted to varying degrees by external constraints influencing fishing effort, but the fishery-independent survey wasn’t affected and hence there remains an unbroken survey time-series for the fishery extending back to 1989. The eHCR was shown to be reasonably robust because it incorporates longer-term trends over a 5-year period, and accords substantially more weighting (80%) to the fishery-independent survey rather than CPUE data which can be affected by trade and other disruptions. Despite the eHCR not having been tested for scenarios such as a global pandemic, this robustness is a positive given the types of disruptions we will likely face in future climate. The weak links identified in the supply chain were the same as those previously highlighted as sensitive to climate change disruptions. Our supply chain analysis quantifies the impact on system resilience of alternative paths connecting producers to consumers and reinforces that supply chains may be particularly vulnerable to external disruptions if they are not sufficiently erse.
Publisher: Springer Science and Business Media LLC
Date: 20-04-2022
DOI: 10.1038/S41531-022-00305-Y
Abstract: Previous studies have shown less access to deep brain stimulation (DBS) for Parkinson’s disease (PD) in women compared to men raising concerns about a potential gender gap resulting from nonclinical factors or gender differences in clinical efficacy for postoperative quality of life (QoL), motor, and nonmotor symptoms (NMS) outcomes. This was a cross-sectional and a longitudinal, prospective, observational, controlled, quasi-experimental, international multicenter study. A total s le size of 505 consisted of 316 consecutively referred patients for DBS indication evaluation at the University Hospital Cologne (01/2015–09/2020) and 189 consecutively treated patients at DBS centers in the University Hospitals Cologne and Marburg, Salford’s Royal Hospital Manchester, and King’s College Hospital London. In the cross-sectional cohort, we examined gender proportions at referral, indication evaluations, and DBS surgery. In the longitudinal cohort, clinical assessments at preoperative baseline and 6-month follow-up after surgery included the PD Questionnaire-8, NMSScale, Scales for Outcomes in PD-motor scale, and levodopa-equivalent daily dose. Propensity score matching resulted in a pseudo-randomized sub-cohort balancing baseline demographic and clinical characteristics between women with PD and male controls. 316 patients were referred for DBS. 219 indication evaluations were positive (women n = 102, respectively n = 82). Women with PD were disproportionally underrepresented in referrals compared to the general PD population (relative risk [RR], 0.72 95%CI, 0.56–0.91 P = 0.002), but more likely to be approved for DBS than men (RR, 1.17 95%CI, 1.03–1.34 P = 0.029). Nonetheless, their total relative risk of undergoing DBS treatment was 0.74 (95%CI, 0.48–1.12) compared to men with PD. At baseline, women had longer disease duration and worse dyskinesia. Exploring QoL domains, women reported worse mobility and bodily discomfort. At follow-up, all main outcomes improved equally in both genders. Our study provides evidence of a gender gap in DBS for PD. Women and men with PD have distinct preoperative nonmotor and motor profiles. We advocate that more focus should be directed toward the implementation of gender equity as both genders benefit from DBS with equal clinical efficacy. This study provides Class II evidence of beneficial effects of DBS in women with PD compared to male controls.
Publisher: Springer Science and Business Media LLC
Date: 18-04-2023
DOI: 10.1038/S41467-023-37385-0
Abstract: While marine kelp forests have provided valuable ecosystem services for millennia, the global ecological and economic value of those services is largely unresolved. Kelp forests are diminishing in many regions worldwide, and efforts to manage these ecosystems are hindered without accurate estimates of the value of the services that kelp forests provide to human societies. Here, we present a global estimate of the ecological and economic potential of three key ecosystem services - fisheries production, nutrient cycling, and carbon removal provided by six major forest forming kelp genera ( Ecklonia, Laminaria, Lessonia, Macrocystis, Nereocystis , and Saccharina ). Each of these genera creates a potential value of between $64,400 and $147,100/hectare each year. Collectively, they generate between $465 and $562 billion/year worldwide, with an average of $500 billion. These values are primarily driven by fisheries production (mean $29,900, 904 Kg/Ha/year) and nitrogen removal ($73,800, 657 Kg N/Ha/year), though kelp forests are also estimated to sequester 4.91 megatons of carbon from the atmosphere/year highlighting their potential as blue carbon systems for climate change mitigation. These findings highlight the ecological and economic value of kelp forests to society and will facilitate better informed marine management and conservation decisions.
Publisher: Springer Science and Business Media LLC
Date: 18-05-2023
Publisher: Elsevier BV
Date: 04-2023
Publisher: Springer Science and Business Media LLC
Date: 29-11-2012
DOI: 10.1007/S10143-012-0436-8
Abstract: Historically, brain tumour resection has relied upon standardised anatomical atlases and classical mapping techniques for successful resection. While these have provided adequate results in the past, the emergence of new technologies has heralded a wave of less invasive, patient-specific techniques for the mapping of brain function. Functional magnetic resonance imaging (fMRI) and, more recently, diffusion tensor imaging (DTI) are two such techniques. While fMRI is able to highlight localisation of function within the cortex, DTI represents the only technique able to elucidate white matter structures in vivo. Used in conjunction, both of these techniques provide important presurgical information for thorough preoperative planning, as well as intraoperatively via integration into frameless stereotactic neuronavigational systems. Together, these techniques show great promise for improved neurosurgical outcomes. While further research is required for more widespread clinical validity and acceptance, results from the literature provide a clear road map for future research and development to cement these techniques into the clinical setup of neurosurgical departments globally.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 12-2007
Location: Australia
No related grants have been discovered for Christopher Nimsky.