Predictive factors for cranioplasty complications - A decade's experience.

Introduction: Cranioplasty (CP) following craniectomy provides cerebral protection, improves cerebrospinal fluid dynamics, and restores cosmesis. Although often viewed as minor, CP can have major complications. Research question: This study aims to identify the predictive factors for post-operative complications in patients undergoing CP after decompressive craniectomy. Methods: We conducted a retrospective study at a tertiary hospital, analyzing patients who underwent CP after decompressive craniectomy (DC) from 2008 to 2019. Patient demographics, medical history, and surgery details were retrieved from hospital records. Complications included symptomatic intracerebral haemorrhage, extradural or subdural haemorrhage, hydrocephalus, infection, or bone resorption. Results: The study included 168 patients: 139 adults (mean age 47.6 ± 12.68 years) and 29 pediatric patients (mean age 11.8 ± 5.62 years), with a slight male predominance. The overall complication rate was 26.2%, with infection being the most common (8.9%). Predictive factors for CP complications identified by binomial logistic regression, controlling for age and sex, included primary coagulopathy (14.3-fold risk increase, p = 0.034), intraoperative ventricular puncture (7.9-fold risk increase, p = 0.009), and intraoperative dural layer breach (2.8-fold risk increase, p = 0.033). Pre-CP home living was a protective factor. Conclusions: CP requires vigilant management to prevent complications. Primary coagulopathy, intraoperative ventricular puncture, and dural layer breach are significant risk factors for complications.

Cerebral Venous Thrombosis in Patients With Traumatic Brain Injury: Epidemiology and Outcome.

The natural history and epidemiological aspects of traumatic cerebral venous thrombosis (CVT) are not fully understood. Due to the concomitant occurrence with intracranial hemorrhages, guidelines for medical treatment have been highly controversial. In this study, our objective was to carry out an analysis description of the population and to conduct a literature review. A prospectively gathered radiology registry data of patients hospitalized at the tertiary hospital of Centro Hospitalar Universitário do São João, Porto, Portugal, between 2016 and 2021 was carried out. All patients with traumatic brain injury (TBI) and concomitant CVT were identified. CVT was confirmed by CT venogram. Demographic, clinical, and radiological data and their medical management were reported. In-hospital complications and treatment outcomes were compared between patients measured by the Glasgow Outcome Score Extended (GOSE) at discharge and GOSE at three months. There were 41 patients with traumatic CVT admitted to this study. The majority (45.2%) had a hyperdense signal near the lateral sinus at admission, and only 26.2% presented with skull fractures. Of this cohort, 95% had experienced lateral sinus thrombosis. Twenty-five patients (60%) had occlusive venous thrombosis. Venous infarct was the main complication following CVT. Thirty-two patients (78%) were anticoagulated after CVT and four developed complications. At the three-month follow-up after discharge, 28.2% had good recovery (GOSE > 6). This study revealed a higher incidence of CVT in severe TBI and a mild association with skull fractures. There is a higher incidence of CVT in the lateral sinus. Management was inconsistent, with no difference in outcome without or with anticoagulation. Larger, prospective cohort studies are required to better comprehend this condition and determine evidence-based guidelines.

The Importance of the Temporary Clip Removal Phase on Exposure to Hypoxia: On-Line Measurement of Temporal Lobe Oxygen Levels During Surgery for Middle Cerebral Artery Aneurysms.

BACKGROUND: Most studies concerning intraoperative temporary arterial occlusion overlook the period between and after clip placement. OBJECTIVE: To analyze the brain tissue oxygen tension through the process by which anterograde arterial blood flow is re-established after temporary clipping (TR). METHODS: In this prospective observational study, patients who presented to surgery for middle cerebral artery aneurysms were continuously monitored with ICM+, to obtain temporal (downstream) PbtO2 levels while M1 segment temporary clips were applied and removed. PbtO2 changes were analyzed and compared with the clipping phase, and measures of exposure to hypoxia were defined and assessed during both phases and used in a model to test the impact of extending them. RESULTS: Eighty-six TRs (20 patients) were recorded. The mean acquired amount of time per clip release (CR) event was 336.7 seconds. Temporary clip removal produced specifically shaped, highly individual PbtO2 curves that correlated with their corresponding clipping phase events but developing slower and less consistently. The CR phase was responsible for greater cumulative exposure to hypoxia than the clip application phase through the first and second minutes of each. In our model, the duration of the TR phase was mostly responsible for the total exposure to hypoxia, and longer CR phases reduced the mean exposure to hypoxia. CONCLUSION: During the clip removal phase, the brain tissue is still exposed to oxygen levels that are significantly below the baseline, reverting through a singular, dynamic process. Therefore, it must be regarded by surgeons with the same degree of attention as its counterpart.

Selection bias in patients proposed for neurosurgical versus endovascular treatment of aneurysms of the posterior communicating artery.

BACKGROUND: Microsurgical clipping and endovascular coiling are viable treatment options for posterior communicating artery (PComA) aneurysms, but there are still major limitations to evidence-based decisions regarding standard-of-care treatment. In this study, we aimed at assessing potential selection biases that may influence our ability to extract conclusions about the comparative effectiveness or efficacy of the aneurysm treatment. OBJECTIVE: To study the patient/aneurysm characteristics as possible biases in the option for endovascular or neurosurgical treatment of PComA aneurysms. METHODS: A single-center, retrospective cohort study was performed, including all patients with treated PComA aneurysms with neurosurgical clipping or endovascular coiling between January 2010 and January 2021. Clinical and morphological data were collected from electronic records, and statistical analysis was performed. RESULTS: A total of 64 patients was eligible for inclusion; 24 (37.5%) patients were proposed for neurosurgical treatment, while 40 (62.5%) for endovascular treatment; 10 patients (25%) crossed over to the clipping group whereas none crossed over to the coiling side. Actual treatment analysis showed significantly higher diameters of mother vessel (t-test, p = 0.034) and aneurysm neck (Mann-Whitney, p = 0.029) in the clipping group and higher aspect and dome-to-neck ratios in the endovascular group (Mann-Whitney, p = 0.008). A significantly higher vasospasm frequency was found in the clipping group but only in the intention-to-treat analysis (Chi-square, p = 0.032). CONCLUSION: Significant morphological differences between effective endovascular and surgical groups and differences in intention-to-treat analysis may limit the validity of a direct comparison between treatment options and suggest the presence of a possible selection bias.

Effects of Temporary Clipping as an Expression of Circulatory Individuality: Online Measurement of Temporal Lobe Oxygen Levels During Surgery for Middle Cerebral Artery Aneurysms.

OBJECTIVE: Despite its widespread use, much is left to understand about the repercussions of parent artery temporary clipping in neurosurgery. This study seeks a better comprehension of the subject by aiming at the online measurement of brain tissue oxygen pressure (PbtO2) during such events. METHODS: This was a prospective observational study. Patients submitted to surgery for middle cerebral artery aneurysms (both ruptured and unruptured) were continuously monitored under Intensive Care Monitoring+ software, in order to obtain temporal (downstream) PbtO2 levels while temporary clips were applied. Separate PbtO2 curve events were identified, extracted, and processed. These were studied for assessing intraindividual and interindividual variability and the potential impact of repeated clipping and previous aneurysmal rupture. RESULTS: Eighty-six temporary clippings (from 20 patients) were recorded with a mean duration of 140.8 (41 - 238) seconds. Temporary arterial occlusion at the M1 segment of the middle cerebral artery produced specifically shaped trajectories, characterized by a preclipping PbtO2 level, rapid downward sigmoid-shaped curve, succession of progressively angled slopes, and lower plateau. The steepest slope of the curve correlated strongly with PbtO2 range (P < 0.001, r = 0.944). These features were highly reproducible only intraindividually and did not vary significantly with repeated clippings. CONCLUSIONS: The effects of temporary arterial occlusion on temporal lobe oxygenation demonstrate a high degree of singularity, highlighting the potential benefits of assessing individual available collateral circulation intraoperatively. The "PbtO2 steepest slope" predicted the severity of PbtO2 decrease and was available within the first minute.

Moyamoya Syndrome after Radiation Therapy: a Clinical Report.

Moyamoya syndrome (MMS) is a rare, chronic and progressive vasculopathy with a characteristic angiographic pattern and well-recognized predisposing conditions, such as cranial therapeutic radiation. We report the case of a 36-year-old Caucasian female with a history of craniopharyngioma treated with whole-brain radiotherapy 20 years previously. She was admitted to the emergency department with disorientation and imperceptible speech lasting for 1 hour. Upon examination, she had slight motor aphasia, without sensory or motor deficits. However, the neurological deficits worsened on standing position. The computed tomography (CT) angiogram and transcranial Doppler ultrasonography revealed occlusion of the distal portion of the left internal carotid artery (ICA). Mechanical thrombectomy was attempted without success. Head CT was repeated, revealing left periventricular acute ischaemic stroke. The cerebral angiography showed total occlusion of the left ICA with an exuberant network of transdural collateral vessels, confirming MMS. The patient completed a functional rehabilitation program with progressive improvement of deficits and maintained a multidisciplinary follow-up. MMS is a serious late complication from cranial radiation therapy and a well-described risk factor for ischaemic stroke in younger patients. Therefore, early detection and prompt treatment are mandatory, as the consequences can be disastrous, such as cognitive and neurologic decline due to repeated strokes. LEARNING POINTS: Moyamoya syndrome should be considered in younger patients presenting with acute neurologic deficits, particularly those treated with cranial radiotherapy.The treatment of acute stroke in patients with moyamoya syndrome should include intravenous hydration and avoidance of hypotension.The benefit of antiplatelet agents is limited and equivocal for patients with moyamoya syndrome and oral anticoagulants are not recommended for long-term treatment.

Plateau Waves of Intracranial Pressure and Multimodal Brain Monitoring.

The aim of this study was to describe multimodal brain monitoring characteristics during plateau waves of intracranial pressure (ICP) in patients with head injury, using ICM+ software for continuous recording. Plateau waves consist of an abrupt elevation of ICP above 40 mmHg for 5-20 min. This is a prospective observational study of patients with head injury who were admitted to a neurocritical care unit and who developed plateau waves. We analyzed 59 plateau waves that occurred in 8 of 18 patients (44 %). At the top of plateau waves arterial blood pressure remained almost constant, but cerebral perfusion pressure, cerebral blood flow, brain tissue oxygenation, and cerebral oximetry decreased. After plateau waves, patients with a previously better autoregulation status developed hyperemia, demonstrated by an increase in cerebral blood flow and brain oxygenation. Pressure and oxygen cerebrovascular reactivity indexes (pressure reactivity index and ORxshort) increased significantly during the plateau wave as a sign of disruption of autoregulation. Bedside multimodal brain monitoring is important to characterize increases in ICP and give differential diagnoses of plateau waves, as management of this phenomenon differs from that of regular ICP.

Predictive value of intraoperative neurophysiologic monitoring in assessing long-term facial function in grade IV vestibular schwannoma removal.

BACKGROUND: Despite routine use of intraoperative neuromonitoring in acoustic neuroma removal, its application in predicting long-term facial function is limited. METHODS: Prospective recording of facial nerve function and subsequent review of intraoperative neurophysiologic data. Stimulation of the facial nerve was performed proximal and distal to the tumor locus after tumor removal with measurement of amplitude and latency responses in the orbicularis oculi and oris muscles. Prospective review of current facial nerve function was performed using the House-Brackmann (HB) scoring system. Good facial function was determined as HB I/II and HB III-VI was considered poor facial function. Minimum follow-up time was 15 months, and averaged 40 months. RESULTS: Twenty-four grade IV acoustic neuromas (54 % larger than 4 cm) were completely removed from October 2008 to November 2013. Nine patients (37.5 %) had HB I/II and 15 (62.5 %) had HB III-VI. The poor prognosis group had a higher latency than the good prognosis group (p = 0.045). Lower proximal amplitude was detected in the poor prognosis group (p = 0.046). Lower proximal-to-distal amplitude ratio was also detected in the poor prognosis group (p = 0.052). Amplitude ratio cut-offs of 0.44 and 0.25 were able to predict poor prognosis with sensitivity of 0.73 and 0.4 and specificity of 0.78 and 1, respectively (p = 0.046). CONCLUSIONS: Lower proximal amplitude and proximal-distal amplitude ratio were previously reported as predictors of poor facial function in different sizes of vestibular schwannomas. We observed that the same applies specifically for large-sized, completely removed, grade IV tumors. Additionally, we describe a difference in proximal latency time between the good and poor prognosis groups, which was not previously reported.

Optimal Cerebral Perfusion Pressure Management at Bedside: A Single-Center Pilot Study.

BACKGROUND: Guidelines recommend cerebral perfusion pressure (CPP) values of 50-70 mmHg and intracranial pressure lower than 20 mmHg for the management of acute traumatic brain injury (TBI). However, adequate individual targets are still poorly addressed, since patients have different perfusion thresholds. Bedside assessment of cerebral autoregulation may help to optimize individual CPP-guided treatment. OBJECTIVE: To assess staff compliance and outcome impact of a new method of autoregulation-guided treatment (CPPopt) based on continuous evaluation of cerebrovascular reactivity (PRx). METHODS: Prospective pilot study of severe TBI adult patients managed with continuous multimodal brain monitoring in a single Neurocritical Care Unit (NCCU). Every minute CPPopt was automatically estimated, based on the previous 4-h window, as the CPP with the lowest PRx indicating the best cerebrovascular pressure reactivity. Patients were managed with CPPopt targets whenever possible and otherwise CPP was managed following general/international guidelines. In addition, other offline CPPopt estimates were calculated using cerebral oximetry (COx-CPPopt), brain tissue oxygenation (ORxs-CPPopt), and cerebral blood flow (CBFx-CPPopt). RESULTS: Eighteen patients with a total multimodal brain monitoring time of 5,520 h were enrolled. During the total monitoring period, 11 patients (61 %) had a CPPopt U-shaped curve, 5 patients (28 %) had either ascending or descending curves, and only 2 patients (11 %) had no fitted curve. Real CPP correlated significantly with calculated CPPopt (r = 0.83, p < 0.0001). Preserved autoregulation was associated with greater Glasgow coma score on admission (p = 0.01) and better outcome (p = 0.01). We demonstrated that patients with the larger discrepancy (>10 mm Hg) between real CPP and CPPopt more likely have had adverse outcome (p = 0.04). Comparison between CPPopt and the other estimates revealed similar limits of precision. The lowest bias (-0.1 mmHg) was obtained with COx-CPPopt (NIRS). CONCLUSION: Targeted individual CPP management at the bedside using cerebrovascular pressure reactivity seems feasible. Large deviation from CPPopt seems to be associated with adverse outcome. The COx-CPPopt methodology using non-invasive CO (NIRS) warrants further evaluation.

Kidney-brain link in traumatic brain injury patients? A preliminary report.

BACKGROUND: Kidney hyperfiltration with augmented renal clearance is frequently observed in patients with traumatic brain injury. The aim of this study is to report preliminary findings about the relationship between brain autoregulation impairment, estimated kidney glomerular filtration rate and outcome in critically ill patients after severe traumatic brain injury. METHODS: Data collected from a cohort of 18 consecutive patients with severe traumatic brain injury managed with ICP monitoring in a Neurocritical Care Unit, were retrospectively analyzed. Early morning blood tests were performed for routine chemistry assessments and we analyzed creatinine and estimated creatinine clearance, osmolarity, and sodium. Daily norepinephrine dose, protein intake, and water balance were documented. Time average of brain monitoring data (intracranial pressure, cerebral perfusion pressure, and cerebrovascular reactivity pressure index--PRx) were calculated for 6 h before blood sample tests. Patient outcome was evaluated using Glasgow outcome scale at 6-month follow-up, considering nonfatal outcome if GOS ≥ 3 and fatal outcome if GOS < 3. Multiple linear regression models were used to study the crude and adjusted effects of the above variables on PRx throughout time. RESULTS: A total of 199 complete daily observations from 18 adult consecutive multiple trauma patients with severe traumatic brain injury were analyzed. At hospital admission, the median post-resuscitation Glasgow coma score was 6 (range 3-12), mean SAPSII score was 44.65 with predicted mortality of 36 %. Hospital mortality rate was 27 % and median GOS at 6 month after discharge was 3. Creatinine clearance (CrCl) was found to have a negative correlation with PRx (Pearson correlation--0.82), with statistically significant crude (p < 0.001) and adjusted (p = 0.001) effects. For each increase of 10 ml/min in CrCl (estimated either by the Cockcroft-Gault or by Modification of Diet in Renal Disease Study equations) a mean decrease in PRx of approximately 0.01 was expected. Amongst possible confounders only norepinephrine was shown to have a significant effect. Mean PRx value for outcome fatal status was greater than mean PRx for nonfatal status (p < 0.05), regardless of the model used for the CrCl estimation. CONCLUSIONS: Better cerebral autoregulation evaluated with cerebrovascular PRx is significantly correlated with augmented renal clearance in TBI patients and associates with better outcome.

Traumatic brain injury in Portugal: trends in hospital admissions from 2000 to 2010.

INTRODUCTION: Traumatic brain injury has a considerable socio-economic impact, being a major cause of morbi-mortality, often with permanent disability. We sought to characterize health resource utilization of adult traumatic brain injury patients in Portugal between 2000 and 2010. MATERIAL AND METHODS: Retrospective study of medical records of adult patients with ICD9 diagnostic code of traumatic brain injury included in the National Diagnosis Related Groups Database from 2000-2010. Descriptive statistical analysis was performed and trends during the decade were evaluated. RESULTS: We analysed 72 865 admissions to 111 hospitals, 64.1% males, mean age 57.9 ± 21.8 years (18-107). We found a decrease in number of traumatic brain injury in younger patients and an increase in older ones. The number of traffic accidents decreased and the number of falls increased. There was an increase of moderate to severe traumatic brain injury admissions: 47.2% in 2000 / 80% in 2010. Patients admitted in Intensive Care have nearly doubled (15.8% vs 29.5%) as well as the number submitted to neurosurgical procedures (8.2% vs 15.2%). Total mortality increased from 7.1% to 10.6%. DISCUSSION: The decrease of traumatic brain injury may be associated with the trauma prevention campaigns, road network improvement and health politics. The increase in mortality may be related to better pre-hospital care, enabling more severe cases to arrive in hospital alive, and although treated more frequently in Intensive Care and requiring more neurosurgical procedures, they end up having higher mortality. Also this may be due to an increase in patients' age and worse pre-morbid status. CONCLUSION: Traumatic brain injury in Portugal is changing. Although hospital admissions due to global traumatic brain injury have decreased, mortality rate has increased.

Introdução: O traumatismo crânio-encefálico tem um impacto sócio-económico considerável, sendo uma importante causa de mobimortalidade, frequentemente causador de incapacidade permanente. Procuramos caracterizar a utilização dos recursos de saúde de adultos com traumatismo crânio-encefálico em Portugal entre 2000-2010. Material e Métodos: Estudo retrospectivo de registos de adultos com código ICD9 de traumatismo crânio-encefálico incluídos na Base-de-Dados Nacional de Grupos Diagnósticos Homogéneos de 2000-2010. Realizamos uma análise estatística descritiva e avaliamos as tendências durante a década. Resultados: Analisamos 72 865 admissões em 111 hospitais, 64,1% do sexo masculino, idade média de 57,9 ± 21,8 anos (18-107). Encontramos uma diminuição no número de traumatismo crânio-encefálico em pacientes jovens e um aumento nos mais velhos. O número de acidentes de trânsito diminuiu e o número de quedas aumentou. Houve um aumento de traumatismos crânio-encefálicos moderados-graves internados: 47,2% em 2000 / 80% em 2010. O número de admissões em Cuidados Intensivos quase duplicou (15,8% vs 29,5%), assim como o número de procedimentos neurocirúrgicos efectuados (8,2% vs 15,2%). A mortalidade total aumentou de 7,1% para 10,6%. Discussão: A diminuição do traumatismo crânio-encefálico observada pode estar associada com as campanhas de prevenção rodoviária, melhoria da rede rodoviária e políticas de saúde. O aumento da mortalidade poderá ser explicado pelo melhor atendimento pré-hospitalar, permitindo que casos mais graves cheguem ao hospital com vida e, embora tratados com mais frequência em Cuidados Intensivos e exigindo procedimentos neurocirúrgicos, vêm a falecer. Por outo lado, o aumento da idade dos doentes presumivelmente com maiores co-morbilidades associadas ao envelhecimento também estará a contribuir para a maior mortalidade. Conclusão: O traumatismo crânio-encefálico em Portugal está a mudar. Embora as admissões hospitalares por traumatismo crânioencefálico tenham diminuído, a mortalidade aumentou.

Post-traumatic multimodal brain monitoring: response to hypertonic saline.

Emerging evidence suggests that hypertonic saline (HTS) is efficient in decreasing intracranial pressure (ICP). However there is no consensus about its interaction with brain hemodynamics and oxygenation. In this study, we investigated brain response to HTS bolus with multimodal monitoring after severe traumatic brain injury (TBI). We included 18 consecutive TBI patients during 10 days after neurocritical care unit admission. Continuous brain monitoring applied included ICP, tissue oxygenation (PtO2) and cerebral blood flow (CBF). Cerebral perfusion pressure (CPP), cerebrovascular resistance (CVR), and reactivity indices related to pressure (PRx) and flow (CBFx) were calculated. ICM+software was used to collect and analyze monitoring data. Eleven of 18 (61%) patients developed 99 episodes of intracranial hypertension (IHT) greater than 20 mm Hg that were managed with 20% HTS bolus. Analysis over time was performed with linear mixed-effects regression modelling. After HTS bolus, ICP and CPP improved over time (p<0.001) following a quadratic model. From baseline to 120 min, ICP had a mean decrease of 6.2 mm Hg and CPP a mean increase of 3.1 mmHg. Mean increase in CBF was 7.8 mL/min/100 g (p<0.001) and mean decrease in CVR reached 0.4 mm Hg*min*100 g/mL (p=0.01). Both changes preceded pressures improvement. PtO2 exhibited a marginal increase and no significant models for time behaviour could be fitted. PRx and CBFx were best described by a linear decreasing model showing autoregulation recover after HTS (p=0.01 and p=0.04 respectively). During evaluation, CO2 remained constant and sodium level did not exhibit significant variation. In conclusion, management of IHT with 20% HTS significantly improves cerebral hemodynamics and cerebrovascular reactivity with recovery of CBF appearing before rise in CPP and decrease in ICP. In spite of cerebral hemodynamic improvement, no significant changes in brain oxygenation were identified.

Pressures, flow, and brain oxygenation during plateau waves of intracranial pressure.

BACKGROUND: Plateau waves are common in traumatic brain injury. They constitute abrupt increases of intracranial pressure (ICP) above 40 mmHg associated with a decrease in cerebral perfusion pressure (CPP). The aim of this study was to describe plateau waves characteristics with multimodal brain monitoring in head injured patients admitted in neurocritical care. METHODS: Prospective observational study in 18 multiple trauma patients with head injury admitted to Neurocritical Care Unit of Hospital Sao Joao in Porto. Multimodal systemic and brain monitoring of primary variables [heart rate, arterial blood pressure, ICP, CPP, pulse amplitude, end tidal CO2, brain temperature, brain tissue oxygenation pressure, cerebral oximetry (CO) with transcutaneous near-infrared spectroscopy and cerebral blood flow (CBF)] and secondary variables related to cerebral compensatory reserve and cerebrovascular reactivity were supported by dedicated software ICM+ ( www.neurosurg.cam.ac.uk/icmplus) . The compiled data were analyzed in patients who developed plateau waves. RESULTS: In this study we identified 59 plateau waves that occurred in 44% of the patients (8/18). During plateau waves CBF, cerebrovascular resistance, CO, and brain tissue oxygenation decreased. The duration and magnitude of plateau waves were greater in patients with working cerebrovascular reactivity. After the end of plateau wave, a hyperemic response was recorded in 64% of cases with increase in CBF and brain oxygenation. The magnitude of hyperemia was associated with better autoregulation status and low oxygenation levels at baseline. CONCLUSIONS: Multimodal brain monitoring facilitates identification and understanding of intrinsic vascular brain phenomenon, such as plateau waves, and may help the adequate management of acute head injury at bed side.

Trans-lamina terminalis approach for third ventricle and suprasellar tumours.

BACKGROUND: The trans-lamina terminalis (TLT) approach to the suprasellar region and third ventricle is complex, with risks of visual and hormonal deficits. However, the postoperative deficits might not be directly related to opening of the lamina terminalis but to the close relationship of tumours with vital neural and vascular structures. The analysis of results using this approach was the objective of this study. MATERIAL AND METHODS: The TLT approach was used in 29 patients (18 craniopharyngiomas, 5 astrocytomas, 5 germinomas and 1 ganglioglioma). The extent of tumour removal, mortality and morbidity (especially visual or hormonal deficits) were studied. RESULTS: Complete tumour removal was achieved in 15 patients, subtotal extensive removal (more than 90%) in 9 cases and partial removal in 5 cases. Panhypopituitarism developed in 22 patients. Total tumour removal was associated with the development of endocrinological disturbances. There was worsening or the onset of new visual field defects in 4 cases. Postoperative endocrine and visual deficits were in the range generally described regarding surgery for tumours in this region. CONCLUSION: The TLT approach allows for extensive removal of third ventricle and suprasellar tumours, without increased risks of visual and hormonal deficits, compared to those described regarding surgery for lesions in this region.

The infratentorial supracerebellar approach in surgery of lesions of the pineal region.

BACKGROUND: Surgery of pineal region lesions is considered a challenging task, due to the particular relationship of lesions in this location with neural and vascular structures. Few series with a significant experience of dealing with these patients have been reported. METHODS: We review our experience using infratentorial supracerebellar approach in the surgery of pineal region, regarding the extension of the removal, postoperative morbidity, and discussing details of the surgical technique. In all cases, a supracerebellar infratentorial approach was used in the semi sitting position. RESULTS: A total of 32 patients were operated in the past 20 years (3 germinomas, 3 teratoma, 3 pineocitoma, 2 pineal tumor of intermediate differentiation, 6 pineoblastomas, 6 low grade astrocytoma, 2 glioblastoma, 2 metastasis, 1 ependymoma, 1 epidermoid tumor, 1 cavernoma, and 2 arachnoid cyst). Total removal was achieved in 15 cases and subtotal extensive removal in 7 patients. In the remaining cases, only partial removal was possible, due to the involved pathological types. There was no surgical mortality and no cases of cerebellar venous infarction. Morbidity consisted of transient ocular movement disturbance in 14 patients, transient ataxia in 3 patients, and 1 case of local cerebrospinal fluid (CSF) fistula with meningitis that required surgical treatment. CONCLUSION: Supracerebellar infratentorial is a safe approach to lesions in the pineal region, and total or extensive subtotal removal is possible in most cases, with acceptable morbidity.

Reversible parkinsonism due to a large intracranial tumour.

A 77-year-old woman presented with progressively worsening apathy, depression, urinary incontinence and slowness of movement for the past 1 year. Asymmetric akinetic-rigid parkinsonism and mild left-sided hyper-reflexia were seen on examination. No ocular movement impairment, cerebellar or sensory signs were noticed. Routine laboratory testing was normal. Brain imaging revealed a large frontal tumour which was subsequently excised and pathologically confirmed as a meningioma. Marked clinical improvement was documented 3 months after surgery, and persistent clinical and imaging remission have been confirmed annually for the following 3 years. There have been some reports of parkinsonism associated with intracranial tumours. Although this is probably an uncommon situation, it is potentially treatable, and symptoms might even remit completely following successful management. Parkinson's disease is a common cause of parkinsonism, but alternative aetiologies should be suspected whenever atypical findings are demonstrated by clinical history or examination.

Surgical removal of giant acoustic neuromas.

OBJECTIVE: The authors present the outcome of radical surgical removal of giant acoustic neuromas. METHODS: Twenty-nine patients with acoustic neuroma with maximum diameter greater than 40 mm, submitted to surgery between the years 2005 and 2010, were reviewed by a retrospective study. The extension of tumor removal, surgical morbidity, facial nerve function, hearing, and evolution after surgery of preoperative neurologic conditions were the studied parameters. RESULTS: All tumors were completely removed by a retrosigmoid approach, without perioperative mortality. As complications related to the surgery, there were three cases of local cerebrospinal fluid leak, one case of nasal cerebrospinal fluid leak, two cases of meningitis, one pseudomeningocele, and one case of transient lower cranial nerve dysfunction. The anatomic integrity of the facial nerve was preserved in 86% and facial function in 72%. In the 21 patients who did not need hypoglossal-facial anastomosis (72%), facial function was excellent or good (HB I-II) in 13 cases (45%), fair (HB III) in 5 cases (17%), and poor (HB IV) in 3 cases (10%). Before surgery, 12 patients (41%) had useful (H2) or moderate (H3) hearing. In 7 of these 12 patients (58%), it was possible to preserve some hearing function (with moderate hearing), after surgical removal of the tumors. Six patients presented with radiologic signs of hydrocephalus, two of them with visual disturbances. Two patients presented with trigeminal neuralgia (one contralateral), three with facial sensory loss and one with swallowing problems, that disappeared after surgery. CONCLUSIONS: Total removal of large acoustic neuroma can be achieved by retrosigmoid approach with acceptable morbidity and no mortality. Preoperative neurologic symptoms recovered after surgery in most cases. Facial function preservation was possible in the majority of cases. Even in large tumors, hearing preservation should be attempted if the patient has useful hearing preoperatively.

Monitoring of brain oxygenation in surgery of ruptured middle cerebral artery aneurysms.

BACKGROUND: The occurrence of brain ischemic lesions, due to temporary arterial occlusion or incorrect placement of the definitive clip, is a major complication of aneurysm surgery. Temporary clipping is a current technique during surgery and there is no reliable method of predicting the possibility of ischemia due to extended regional circulatory interruption. Even with careful inspection, misplacement of the definitive clip can be difficult to detect. Brain tissue oxygen concentration (PtiO(2)) was monitored during surgery of middle cerebral artery (MCA) aneurysm presenting with subarachnoid hemorrhage (SAH), for detection of changes in brain oxygenation due to reduced blood flow, as a predictor of ischemic events, during temporary clipping and after definitive clipping. METHODS: PtiO(2) was monitored during surgery of 13 patients harboring MCA aneurysms presenting with SAH, using a polarographic microcatheter (Licox, GMS, Kiel, Germany) placed in the territory of MCA. RESULTS: A decrease in PtiO(2) values was verified in every period of temporary clipping. Brain infarction occurred in 2 patients; in both cases, there was a decrease in PtiO(2) greater than 80% from basal value, a minimum value of less than 2 mmHg persisting for 2 or more minutes during temporary clipping, and an incomplete recovery of PtiO(2) after definitive clipping. In 2 patients, incomplete recovery of values after definitive clipping led to verification of inappropriate placement and repositioning of the clip. CONCLUSION: The results suggest that intraoperative monitoring of PtiO(2) may be a useful method of detection of changes in brain tissue oxygenation during MCA aneurysm surgery. Postoperative infarction in the territory of MCA developed in cases with an abrupt decrease of PtiO(2) and a very low and persistent minimum value, during temporary clipping, and an incomplete recovery after definitive clipping. Verification of clip position should be considered when there is an incomplete recovery or a persistent fall in PtiO(2) after definitive clipping.