Effects of the Prone and the Sitting Positions on the Brain Oxygenation in Posterior Fossa Surgery...
Infratentorial NeoplasmsThe sitting or prone positions are used for posterior fossa surgery. Although the sitting position may cause hemodynamic instability, venous air embolism, it also provides optimum access to midline lesions, decreases intracranial pressure. The sitting position has not been only used in neurosurgery, it has been also used in the shoulder surgery. The sitting position related hypotension may reduce the cerebral perfusion pressure, therefore may cause cerebral ischemia. The sitting position related cerebral ischemia has been shown in the shoulder surgery. The non invasive cerebral oxymetry (INVOS-Covidien) has been used to measure cerebral oxygen saturation. Some studies has been done to investigate whether the sitting position cause cerebral desaturation or not in the shoulder surgery by non invasive cerebral oxymetry. The study results are controversial. It has been investigated that the effect of the prone position on the cerebral oxygenation in the spine surgery and the investigators found that the prone position may increase cerebral oxygenation. However, all studies have been done in patients without intracranial pathology. We speculate that due to the sitting position reduces the intracranial pressure, it may improve the cerebral oxygenation in the patients have intracranial pathology. Therefore we will compare the sitting and the prone positions effects on the cerebral oxygenation in patients undergoing posterior fossa tumour surgery by non invasive cerebral oxymetry. Method: 62 patients have posterior fossa tumour will include the study. Patients will divide to 2 groups according to the surgical position, the prone (n=31) or the sitting (n=31). Patients heart rate, mean blood pressure (MAP), cerebral oxygen saturation (SctO2), peripheral oxygen saturation (SpO2), BIS values will record before the induction of anesthesia. Five minutes after the standard anesthesia induction all values will record and it will accept as a baseline. After that all these parameters will record in each 3 minutes until the beginning of surgery. Mean while, more than 5 % reduction in SctO2 and more than 20 % reduction in SctO2 and/or MAP will record. As well as, if the SctO2 reduces than 55 and 60 %, it will record.
PRICE Survey Of Extubation Following Infratentorial Craniotomy
Infratentorial NeoplasmsThe PRICE study primarily aims to identify predictors of early extubation following elective infratentorial craniotomy in adults. It also aims to (i) measure the rate of early extubation in different clinical settings; and (ii) study how the decision to extubate early is made and communicated in clinical practice. The first phase of the study (PRICE1) is a brief online survey addressed to physicians in charge of neurosurgical patients (neuroanesthesiologists, neurosurgeons, neurocritical care specialists) in multiple countries.
Advanced MRI for Posterior Fossa Tumours
Cerebellar MutismPosterior Fossa SyndromePost-operative paediatric cerebellar mutism syndrome (pCMS) is a well-recognised complication of resective surgery for brain tumours of the cerebellum and fourth ventricle in children. Occurring in around 25% of infratentorial craniotomies, it is characterised by a delayed onset of mutism and emotional lability, and may comprise motoric and cognitive cerebellar deficits. Transient mutism gives way to prolonged, and often incomplete, recovery. Neuroimaging studies are beginning to reveal anatomical and functional aberrancies in the brain of children with pCMS. The cerebellar efferent pathways are likely to be implicated as a neuroanatomical substrate in the development of pCMS, as shown by a handful of diffusion tractography studies to date. However, the pathophysiology of this condition still remains unclear. Hypoperfusion of supratentorial cortical and subcortical structures may mediate the speech and behavioural deficits seen in pCMS, and is a candidate for a causal pathophysiological mechanism. This study aims to prospectively image children with pCMS using advanced MRI techniques including diffusion tractography and arterial spin labelling, and to correlate this with clinical descriptions of the syndrome. All children referred to Great Ormond Street Hospital for Children with a posterior fossa brain tumour will be imaged pre-operatively, post-operatively and at delayed follow-up. In tandem with this, clinical assessments will be made of children post-operatively to ascertain which patients develop pCMS. In addition, anonymised advanced MRI data on healthy controls will be used as a comparator group.
Child's Study of the Impact of PF Lesion on Motor Skills, Language, Cognitive Functioning and Social...
MedulloblastomaChildhood3 moreOne of the major complications of posterior fossa surgery is Posterior Fossa Syndrome (PFS). This syndrome is due to a possible complication of surgical excision of a tumor of the cerebellum (4th ventricle) and is characterized by transient postoperative mutism, dysarthria, behavioral, and affective disorders, as well as motor disorders. PFS is thought to be related to axonal lesions. The long-term consequences on the cognitive and psychosocial sphere of PFS have been widely documented. On the other hand, the literature concerning the consequences of this syndrome on language is much restricted. Beyond the language, the role of cerebellum would be central in cognition, some authors even comparing it to a great "conductor" who would underlie the learning of most motor and cognitive automatisms.