Healthcare is under pressure: an ageing population, healthcare-staff shortage, quality (healthcare outcomes) must increase and costs must be reduced.Yet, what are the outcomes of healthcare?For... Show moreHealthcare is under pressure: an ageing population, healthcare-staff shortage, quality (healthcare outcomes) must increase and costs must be reduced.Yet, what are the outcomes of healthcare?For some conditions, quality of care is measured for every patient. Unfortunately, this is not the case for prostate cancer and lumbar disk herniation in the Netherlands. We used claims data to evaluate healthcare outcomes and volume-outcome relationships.Examples of our results:Prostate cancer:• More than 30% of patients is incontinent 1 year after radical prostatectomy• Large differences between hospitals (19%-85%)• Risk of incontinence is 52% lower at highest-volume hospitalsLumbar disk herniation:• One year after hernia surgery, 23% of patients have one or more undesirable outcomes (e.g. re-operation, use of opioids).• Wide variation in number of operations and outcomes per hospitalOur recommendations:• Reconsider the disproportionately strict interpretation of the GDPR (AVG) for healthcare research• Unlock the huge potential of healthcare research based on existing data • Make routine measurement of healthcare outcomes a national standard, for prostate cancer even on a per surgeon level• Centralization of care should be combined with outcome measurement• Hospitals should share healthcare outcomes with patients• Our results urge doctors, health insurers, patient organizations and policymakers to take action Show less
A traumatic acute subdural hematoma, a bleeding between the skull and the brain after a traumatic injury, is associated with high mortality and long-term neurocognitive morbidity. One of the age... Show moreA traumatic acute subdural hematoma, a bleeding between the skull and the brain after a traumatic injury, is associated with high mortality and long-term neurocognitive morbidity. One of the age-old cornerstones of treatment is immediate neurosurgical management, with either acute hematoma evacuation or initial conservative treatment with potential delayed surgery. In patients with rapid neurological deterioration because of a large acute subdural hematoma, the indication is clear; without acute surgery, high intracranial pressure will persist and the patient will die. In most cases however, the benefit of acute surgery is less clear, and patients may, at least initially, be managed conservatively. This strategy requires balancing potential complications of surgery against the risk of irreversible neurological deterioration with initial conservative treatment.Neurosurgeon Thomas van Essen first shows that appropriate evidence of acute surgery versus conservative treatment for acute subdural hematoma is lacking, although among comatose patients, acute surgery has a clear benefit. Subsequently, he demonstrates that among neurosurgeons treatment preferences strongly and consistently differ, resulting in large practice variations. Using these treatment preferences, he then shows that patients treated in centers that prefer acute surgery (over conservative treatment) have equal outcomes to patients treated in centers that prefer conservative treatment. Additionally, with regard to surgical technique, primary decompressive craniectomy - leaving the bone flap out after evacuation of the acute subdural hematoma - might not lead to better outcomes as compared to craniotomy – replacing the bone flap directly. The thesis has practical implications for clinical practice: When the neurosurgeon has no clear preference for acute surgery or conservative treatment, treat patients with a traumatic acute subdural hematoma conservatively. And, primary decompressive craniectomy in traumatic acute subdural hematoma should be restricted to patients in whom replacement of the bone flap is not possible due to severe brain swelling. Show less
Despite improved surgical and adjuvant treatment options, malignant brain tumors remain non-curable to date. The thin line between treatment effectiveness and patient harms underpins the importance... Show moreDespite improved surgical and adjuvant treatment options, malignant brain tumors remain non-curable to date. The thin line between treatment effectiveness and patient harms underpins the importance of tailoring clinical management to the individual brain tumor patient. Over the past decades, the volume and complexity of clinically-derived patient data (i.e., imaging, genomics, free-text etc.) is increasing exponentially. Machine learning provides a vast range of algorithms that can learn from this data and guide clinical decision-making by providing accurate patient-level predictions. The current thesis describes several studies along the continuum of the machine learning spectrum as it applies to neurosurgical oncology. Part I investigates postoperative complications and risk factors in patients operated for a primary malignant brain tumor. Part II describes de development of a model for the prediction of individual-patient survival in glioblastoma patients. Part III encompasses the development of a natural language processing framework for automated medical text analysis. Machine learning algorithms should be considered as an extension to statistical approaches and exist along a continuum determined by how much is specified by humans and how much is learnt by the machine. Although machine learning algorithms can produce highly accurate predictions based on high-dimensional data, clinicians and researchers should interpret the clinical implications of these predictions on case-by-case basis. Show less
Patient outcomes have been tremendously improved through neurosurgical innovation for which there are countless examples. However, how neurosurgical innovation occurs generally lacks structure.... Show morePatient outcomes have been tremendously improved through neurosurgical innovation for which there are countless examples. However, how neurosurgical innovation occurs generally lacks structure. This lack results in several ethical and practical problems related to patient safety. In this thesis, a new framework for neurosurgical innovation is proposed. This framework aims to provide an adequate valuation of structured and careful innovation. In recent neurosurgical innovations, related ethical dillema’s and excisiting frameworks for innovation were evaluated to come to this framework.Based on an extensive review of the literature, several recent neurosurgical innovations were not introduced in a structured fashion. This unstructured introduction holds potentially far-reaching consequences for informed consent, patient safety, and knowledge regarding long-term outcomes.Neurosurgical innovation holds several ethical dilemmas. These dilemmas range from the need to innovate in an emergency setting to the learning curve that every novel procedure brings. This thesis describes these dilemmas in detail and discusses potential solutions.Existing frameworks for innovation in medicine, such as the IDEAL Framework and learning health systems, have limited application to neurosurgery because of its unique patient population. Nevertheless, these frameworks form the inspiration for the beforementioned newly suggested framework for neurosurgical innovation. Show less
We aimed to expand our knowledge about the level of neurocognitive functioning (NCF) and health-related quality of life (HRQoL) in patients with primary and secondary brain tumors during the... Show moreWe aimed to expand our knowledge about the level of neurocognitive functioning (NCF) and health-related quality of life (HRQoL) in patients with primary and secondary brain tumors during the disease course. We found that the tumor itself has the largest negative impact on NCF and HRQoL. At group level, treatment (surgery, radiotherapy and/or chemotherapy) did not seem to have a large extra detrimental effect on the short term. However, subgroups of patients, e.g. patients with tumors in the non-dominant hemisphere and long-term survivors, appeared to be vulnerable for cognitive decline after treatment. At the individual patient level, HRQoL varied to a large degree in the first months after treatment, confirming this is a multidimensional concept and that the impact of treatment differs for the different aspects. With the results from the studies described in this thesis, treatment and individual patient care can be optimized by minimizing the negative impact of treatment, e.g. by intraoperative monitoring of cognition during awake surgery, and by counseling and rehabilitation of patients. Besides, investigators should pay attention to methodological challenges in reporting of neurocognitive outcomes in research, as reporting of these outcomes is currently not sufficient, while evidence can be of value in clinical decision-making. Show less
Cauda equina syndrome (CES) is most commonly caused by lumbar herniated disc; emergency decompressive surgery is essential to increase chances of recovery. Even though micturition, defecation and... Show moreCauda equina syndrome (CES) is most commonly caused by lumbar herniated disc; emergency decompressive surgery is essential to increase chances of recovery. Even though micturition, defecation and/or sexual function are by definition affected in CES patients, little is known about the outcome of these functions after surgical intervention. This thesis provides a comprehensive overview on presentation and on short- and long term outcome of CES after surgical intervention focused on micturition, defecation and sexual function, demonstrating high prevalences of dysfunction even at long term follow up. In addition, this thesis provides insight into attitude and practice patterns of neurosurgeons regarding discussing sexual health and fertility with spinal patients and explores the relationship between presenting MRI features and clinical features (both at outcome and at presentation). Show less
Despite major microsurgical improvements the clinical outcome of peripheral nerve surgery is still regarded as suboptimal. Over the past decade several innovative techniques have been... Show more Despite major microsurgical improvements the clinical outcome of peripheral nerve surgery is still regarded as suboptimal. Over the past decade several innovative techniques have been developed to extend the armamentarium of the nerve surgeon. This thesis evaluates the potential of gene therapy in the context of peripheral nerve repair. The overall goal of the work presented in this thesis is to enhance peripheral nerve regen- eration by stimulating axonal growth and reducing misdirection. We set out to achieve this by increasing the therapeutic potential of Schwann cells through gene therapy. Show less
