Karolina Wartolowska

Karolina Wartolowska
University of Oxford | OX · Nuffield Department of Clinical Neurosciences

MD, DPhil
more at: https://ka-wa.io

About

72
Publications
5,906
Reads
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1,979
Citations
Introduction
Karolina Wartolowska currently works at Centre for Prevention of Stroke and Dementia, University of Oxford working on MRI as marker of treatment response and disease progression in patients with stroke and small vessel disease. For more information on the past and current projects please see http://www.wartolowska.eu.
Additional affiliations
January 2006 - present
University of Oxford
Position
  • Clinical Research Fellow
Description
  • Providing scientific expertise in using neuroimaging as an outcome in clinical trials on drug efficacy; analysis of large-scale clinical and neuroimaging data from the UK Biobank; running research clinics and clinical trial visits for patients with minor stroke; performing human cerebrovascular studies; acquisition and analysis of clinical, cognitive/physiological/neuroimaging data in three randomised controlled trials; neuroimaging pipeline development

Publications

Publications (72)
Article
Pain is a complex and multidimensional experience, which is subjective for an individual and modulated by physiological and psychological factors. Therefore, it is difficult to quantify pain and there are no objective pain measures available at the moment. Neuroimaging provides an objective measure of changes in brain activity related to pain perce...
Article
Full-text available
Objective To investigate whether placebo controls should be used in the evaluation of surgical interventions. Design Systematic review. Data sources We searched Medline, Embase, and the Cochrane Controlled Trials Register from their inception to November 2013. Study selection Randomised clinical trials comparing any surgical intervention with place...
Article
Full-text available
Background Understanding changes in the placebo arm is essential for correct design and interpretation of randomized controlled trials (RCTs). It is assumed that placebo response, defined as the total improvement in the placebo arm of surgical trials, is large; however, its precise magnitude and properties remain to be characterized. To the best of...
Article
Placebos and their beneficial clinical and psychological effects are well-researched, but nocebo effects receive far less attention, despite being highly undesirable. The aim of this restricted scoping review was to examine how nocebo effects are represented in the biomedical literature and to identify the trends and gaps in existing knowledge. Aft...
Article
Background and Purpose Increased cerebral arterial pulsatility is associated with cerebral small vessel disease, recurrent stroke, and dementia despite the best medical treatment. However, no study has identified the rates and determinants of progression of arterial stiffness and pulsatility. Methods In consecutive patients within 6 weeks of trans...
Article
Full-text available
Small vessel disease is associated with age, mean blood pressure (MAP) and blood pressure pulsatility (PP). We used data from the UK Biobank cohort study to determine the relative importance of MAP versus PP driving white matter injury within individual white matter tracts, particularly in the anterior and posterior vascular territory. The associat...
Article
Objective To examine attitudes of Open Label Placebos (OLP) among a national sample of US orthopedic surgeons. Methods Orthopedic surgeons across the US were invited to participate in a brief online cross-sectional survey; n = 687 participated. The survey included a short vignette of a surgeon using adjunctive OLPs in addition to opioids for posto...
Article
Full-text available
Purpose To evaluate the diagnostic accuracy of Gallium-68 prostate-specific membrane antigen positron emission tomography-computed tomography ( ⁶⁸ Ga-PSMA PET/CT) compared with multiparametric magnetic resonance imaging (mpMRI) for detection of metastatic lymph nodes in intermediate to high-risk prostate cancer (PCa). Methods PRISMA-compliant syst...
Article
Full-text available
Background Cerebral small vessel disease (SVD) is associated with increased cerebrovascular pulsatility, endothelial dysfunction, and impaired vascular reactivity. Vasodilating phosphodiesterase inhibitors may improve cardiovascular pulsatility and reactivity, and potentially reduce progression of SVD. Hypothesis: Sildenafil, a PDE5 inhibitor, will...
Article
Small vessel disease and related stroke and dementia risks are linked to aging and hypertension, but it is unclear whether the pulsatile or steady blood pressure (BP) component is more important for the development of macrostructural hyperintensities and microstructural white matter damage. This was a cross-sectional analysis of the UK Biobank coho...
Article
Beat-to-beat variability in blood pressure (BP) is associated with recurrent stroke despite good control of hypertension. However, no study has identified rates of progression of beat-to-beat BP variability (BPV), its determinants, or which patient groups are particularly affected, limiting understanding of its potential as a treatment target. In c...
Article
Full-text available
Aims White matter hyperintensities (WMH) progress with age and hypertension, but the key period of exposure to elevated blood pressure (BP), and the relative role of systolic BP (SBP) vs. diastolic BP (DBP), remains unclear. This study aims to determine the relationship between WMH and concurrent vs. past BP. Methods and results UK Biobank is a p...
Article
Objective The development of persistent pain following total knee arthroplasty (TKA) is common, but its underlying mechanisms are unknown. The goal of the study was to assess brain grey matter structure and its correlation with function of the nociceptive system in people with good and poor outcomes following TKA. Subjects Thirty-one people with L...
Article
Neuromodulation interventions use electrical stimulation to modulate neuronal activity and elicit a therapeutic response. These procedures are generally adjustable, reversible, and have demonstrated some efficacy in the treatment of several conditions, including chronic pain. Despite promising evidence in the field, the general quality of the evide...
Article
Full-text available
The term nocebo effect refers to the harmful outcomes that result from people’s negative beliefs, anticipations, or experiences related to the treatment rather than the pharmacological properties of the treatment. These outcomes may include a worsening of symptoms, a lack of expected improvement, or adverse events, and they may occur after the acti...
Article
Over the past decade, the mechanisms underlying placebo effects have begun to be identified. At the same time, the placebo response appears to have increased in pharmacological trials and marked placebo effects are found in neurostimulation and surgical trials, thereby posing the question whether non-pharmacological interventions should be placebo-...
Article
Full-text available
The term nocebo refers to the worse outcomes or side effects experienced by patients as a result of their negative expectations regarding a treatment. It may distort estimates of treatment effectiveness and safety in both clinical trials and clinical practice; moreover, it may cause discontinuation of therapy or drop out from a trial. Nocebo effect...
Article
Full-text available
Objectives To explore how the concept of randomization is described by clinicians and understood by patients in randomized controlled trials (RCTs) and how it contributes to patient understanding and recruitment. Study Design and Setting Qualitative analysis of 73 audio recordings of recruitment consultations from five, multicenter, UK-based RCTs w...
Conference Paper
Objectives EBM DataLab is a team that aims to produce tools from data, rather than just academic publications. We have a multidisciplinary approach that combines the skills of software engineers, clinicians and academics. In this workshop we will give an overview covering how to make effective interactive services driven by data, through: • Provid...
Preprint
Full-text available
Clinical pain is difficult to study using standard Blood Oxygenation Level Dependent (BOLD) magnetic resonance imaging because it is often ongoing and, if evoked, it is associated with stimulus-correlated motion. Arterial spin labelling (ASL) offers an attractive alternative. This study used arm repositioning to evoke clinically-relevant musculoske...
Article
Inferences about the effects of treatments, including surgical treatments, rely on making comparisons. These comparisons may be with patient’s symptoms before a treatment has been applied. For example, the return of hearing after puncturing the ear drum (tympanotomy) in certain kinds of longstanding deafness can be so dramatic that the change can b...
Article
Full-text available
In this paper, we use evidence from our earlier review of surgical randomised controlled trials with a placebo arm to show that blinding in trials of interventional procedures is feasible. We give examples of ingenious strategies that have been used to simulate the active procedure and to make the placebo control indistinguishable from the active t...
Article
Background Arthroscopic sub-acromial decompression (decompressing the sub-acromial space by removing bone spurs and soft tissue arthroscopically) is a common surgery for subacromial shoulder pain, but its effectiveness is uncertain. We did a study to assess its effectiveness and to investigate the mechanism for surgical decompression. Methods We di...
Article
Background: A lack of objective outcome measures and overreliance on subjective pain reports in early proof-of-concept studies contribute to the high attrition of potentially effective new analgesics. We studied the utility of neuroimaging in providing objective evidence of neural activity related to drug modulation or a placebo effect in a double...
Article
Full-text available
Background: Arthroscopic sub-acromial decompression (decompressing the sub-acromial space by removing bone spurs and soft tissue arthroscopically) is a common surgery for subacromial shoulder pain, but its effectiveness is uncertain. We did a study to assess its effectiveness and to investigate the mechanism for surgical decompression. Methods:...
Article
Full-text available
In this paper, we have used evidence from our earlier review of surgical randomised controlled trials with a placebo arm to show that blinding in trials of interventional procedures is feasible, and that many creative methods can be used to make the active and the placebo procedure as similar as possible. We give examples of ingenious strategies us...
Article
Full-text available
Cellular therapies, such as stem cell–based treatments, have been widely researched and numerous products and treatments have been developed. Despite this, there has been relatively limited use of these technologies in the healthcare sector. This study sought to investigate the perceived barriers to this more widespread adoption. An anonymous onlin...
Article
Full-text available
Background Temporal changes in the placebo arm of randomized controlled trials (RCTs) have not been thoroughly investigated, despite the fact that results of RCTs depend on the comparison between arms. Methods In this update of our earlier systematic review and meta-analysis, we set out to investigate the effect of assessment time and number of vi...
Article
Full-text available
Cellular therapies, such as stem cell based treatments, have been widely researched and numerous products and treatments have been developed. Despite this, there has been relatively limited use of these technologies in the healthcare sector. This study sought to investigate the perceived barriers to this more widespread adoption. An anonymous onlin...
Article
This article will consider how physiological monitoring can be used both as an intrinsic part of an experiment, or for removing unwanted physiological signals from the FMRI time series. As functional MRI is used for a wide variety of applications beyond the identification of regions involved in a task, different sources of noise in the time series...
Article
Full-text available
Background The CONSORT Statement is an evidence-informed guideline for reporting randomised controlled trials. A number of extensions have been developed that specify additional information to report for more complex trials. The aim of this study was to evaluate the impact of using a simple web-based tool (WebCONSORT, which incorporates a number of...
Article
Full-text available
Use of a placebo control in surgical trials is a divisive issue. We argue that, in principle, placebo controls for surgery are necessary in the same way as for medicine. However, there are important differences between these types of trial, which both increase justification and limit application of surgical studies. We propose that surgical randomi...
Article
Full-text available
Background The aim of this study was to investigate the beliefs and attitudes of trainee surgeons regarding placebo interventions, in surgical practice and in research, and to compare them to those of senior orthopaedic surgeons. Methods An invitation to participate in an online survey was sent to all the email addresses in the members’ database of...
Article
Full-text available
Objectives To find evidence, either corroborating or refuting, for many persisting beliefs regarding the feasibility of carrying out surgical randomised controlled trials with a placebo arm, with emphasis on the challenges related to recruitment, funding, anaesthesia or blinding. Design Systematic review. Data sources and study selection The analys...
Article
Full-text available
Placebo surgery – often maligned as ‘sham surgery’ – is a tough sell to patients and to many clinicians. But could surgical research benefit from increased use of placebo control groups?
Article
Full-text available
Arthroscopic subacromial decompression (ASAD) is a commonly performed surgical intervention for shoulder pain. The rationale is that removal of a bony acromial spur relieves symptoms by decompressing rotator cuff tendons passing through the subacromial space. However, the efficacy of this procedure is uncertain. The objective of this trial was to c...
Article
The therapeutic effects of centrally acting pharmaceuticals can manifest gradually and unreliably in patients, making the drug discovery process slow and expensive. Biological markers providing early evidence for clinical efficacy could help prioritize development of the more promising drug candidates. A potential source of such markers is function...
Article
There has been a large increase in basic science activity in cell therapy and a growing portfolio of cell therapy trials. However, the number of industry products available for widespread clinical use does not match this magnitude of activity. We hypothesize that the paucity of engagement with the clinical community is a key contributor to the lack...
Article
Full-text available
To survey surgeons on their beliefs and attitudes towards the use of placebo in surgery. British orthopedic shoulder surgeons, attending a national conference in the United Kingdom, were asked to complete a self-report online questionnaire about their beliefs and attitudes towards the use of placebo related to surgical intervention. The survey incl...
Article
Full-text available
There has been a large increase in basic science activity in cell therapy and a growing portfolio of cell therapy trials. However, the number of industry products available for widespread clinical use does not match this magnitude of activity. We hypothesize that the paucity of engagement with the clinical community is a key contributor to the lack...
Article
Full-text available
Abstract Increased global connectivity has catalyzed technological development in almost all industries, in part through the facilitation of novel collaborative structures. Notably, open innovation and crowd-sourcing-of expertise and/or funding-has tremendous potential to increase the efficiency with which biomedical ecosystems interact to deliver...
Article
Full-text available
Compared to pharmacology, the efficacy of surgery has been very poorly evaluated. Many surgical procedures are carried out on a daily basis without any good evidence to support them. Primarily this is because the methodology for surgical trials offers some unique challenges. Whilst a comparison between two (or more) surgical procedures is possible,...
Article
To investigate whether structural changes are present in the cortical and subcortical gray matter of the brains of patients with rheumatoid arthritis (RA). We used two surface-based style morphometry analysis programs and a voxel-based style analysis program to compare high-resolution structural magnetic resonance imaging data obtained for 31 RA pa...
Conference Paper
The poster is available on Figshare: https://figshare.com/articles/Limbic_structures_and_response_to_anti-TNF_treatment/5830611
Article
Neuroimaging makes it possible to study pain processing beyond the peripheral nervous system, at the supraspinal level, in a safe, noninvasive way, without interfering with neurophysiological processes. In recent years, studies using brain imaging methods have contributed to our understanding of the mechanisms responsible for the development and ma...
Article
This chapter describes how brain imaging methods have been used in studies on pain, what neuroimaging tells us about the role of the central nervous system in pain processing, how being in constant pain affects the brain, and finally, how neuroimaging can be applied to improve the existing analgesic drugs and to discover new therapies. Neuroimaging...
Article
Full-text available
Early after acute ischaemic stroke, elevation of brain temperature might augment tissue metabolic rate and conversion of ischaemic but viable tissue to infarction. This might explain the observed link between pyrexia, severe stroke and poor outcome. We tested this hypothesis by measuring brain temperature and lactate concentration with multi-voxel...
Article
In acute ischemic stroke, the amount of neuronal damage in hyperintense areas on MR diffusion imaging (DWI) is unclear. We used spectroscopic imaging to measure N-acetyl aspartate (NAA, a marker of normal neurons) and lactate (a marker of ischemia) to compare with diffusion and perfusion values in the diffusion lesion in acute ischemic stroke. We r...
Article
Although depressive mood is an important psychological determinate of chronic pain, the neural circuitry that mediates its influence on the pain experience is largely unknown. We used functional magnetic resonance imaging (FMRI) to investigate the neurophysiological interactions between depressive symptoms and disease-relevant pain in rheumatoid ar...
Conference Paper
RESULTS To date, 11 patients have responded positively to the treatment and completed all three sessions. There was a significant change in all the clinical and psychological measures except for pain rating to noxious thermal stimulation. Imaging results: We observed a robust activation in response to both types of painful stimuli. After treatment,...
Article
Pyrexia is associated with poor outcome after stroke, but the temperature changes in the brain after stroke are poorly understood. We used magnetic resonance spectroscopic imaging (water-to-N-acetylaspartate frequency shift) to measure cerebral temperature noninvasively in stroke patients. We performed magnetic resonance diffusion, perfusion (diffu...
Article
A magnetic resonance proton spectroscopic imaging (SI) technique was developed to measure regional brain temperatures in human subjects. The technique was validated in a homogeneous phantom and in four healthy volunteers. Simulations and calculations determined the theoretical measurement precision as approximately +/-0.3 degrees C for individual 1...
Article
Accurate carotid imaging is important for effective secondary stroke prevention. Non-invasive imaging, now widely available, is replacing intra-arterial angiography for carotid stenosis, but the accuracy remains uncertain despite an extensive literature. We systematically reviewed the accuracy of non-invasive imaging compared with intra-arterial an...
Article
In nine healthy subjects, magnetic resonance imaging was used to measure blood flow waveforms in the common (CCA), internal (ICA) and external (ECA) carotid arteries. Useful data were acquired from 14 carotid arteries in total. Flow rates were determined from regions of interest placed over the arteries in CINE-phase contrast velocity encoded image...

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Projects

Projects (6)
Project
Using MRI to investigate disease mechanisms and treatment efficacy in cerebrovascular diseases
Project
To investigate the magnitude and duration of placebo and nocebo effect in randomised controlled trials in order to minimise bias in assessment of treatment efficacy and treatment-associated harms.
Archived project