Supratentorial Lesions Research Articles

Cranial defect and pneumocephalus are associated with significant postneurosurgical positional brain shift: evaluation using upright computed tomography

Only few studies have assessed brain shift caused by positional change. This study aimed to identify factors correlated with a large postneurosurgical positional brain shift (PBS). Sixty-seven patients who underwent neurosurgical procedures had upright computed tomography (CT) scan using settings similar to those of conventional supine CT. The presence of a clinically significant PBS, defined as a brain shift of ≥ 5 mm caused by positional change, was evaluated. The clinical and radiological findings were investigated to identify factors associated with a larger PBS. As a result, twenty-one patients had a clinically significant PBS. The univariate analysis showed that supratentorial lesion location, intra-axial lesion type, craniectomy procedure, and residual intracranial air were the predictors of PBS. Based on the multivariate analysis, craniectomy procedure (p < 0.001) and residual intracranial air volume (p = 0.004) were the predictors of PBS. In a sub-analysis of post-craniectomy patients, PBS was larger in patients with supratentorial craniectomy site and parenchymal brain injury. A large craniectomy area and long interval from craniectomy were correlated with the extent of PBS. In conclusion, patients who undergo craniectomy and those with residual intracranial air can present with a large PBS. In post-craniectomy patients, the predisposing factors of a large PBS are supratentorial craniectomy, presence of parenchymal injury, large skull defect area, and long interval from craniectomy. These findings can contribute to safe mobilization among postneurosurgical patients and the risk assessment of sinking skin flap syndrome.

Barriers and facilitators in the implementation of a telemedicine-based outpatient brain tumor surgery program.

Despite growing evidence on the benefits of outpatient oncological neurosurgery (OON), it is only performed in a few specialized centers and there are no previous descriptions of established OON programs in Europe. Moreover, increasing application of telemedicine strategies, especially after the start of the coronavirus disease 2019 (COVID-19) pandemic, is drastically changing neurosurgical management, particularly in the case of vulnerable populations such as neuro-oncological patients. In this context, the authors implemented an OON program in their hospital with telematic follow-up. Herein, they describe the protocol and qualitatively analyze the barriers and facilitators of the development process. An OON program was developed through the following steps: assessment of hospital needs, specific OON training, multidisciplinary team organization, and OON protocol design. In addition, the implementation phase included training sessions, a pilot study, and continuous improvement sessions. Finally, barriers and facilitators of the protocol's implementation were identified from the feedback of all participants. An OON protocol was successfully designed and implemented for resection or biopsy of supratentorial lesions up to 3 cm in diameter. The protocol included the patient's admission to the day surgery unit, noninvasive anesthetic monitoring, same-day discharge, and admission to the hospital-at-home (HaH) unit for telematic and on-site postoperative care. After a pilot study including 10 procedures in 9 patients, the main barriers identified were healthcare provider resistance to change, lack of experience in outpatient neurosurgery, patient reluctance, and limitations in the recruitment of patients. Key facilitators of the process were the patient education program, the multidisciplinary team approach, and the HaH-based telematic postoperative care. Initiating an OON program with telematic follow-up in a European clinical setting is feasible. Nevertheless, it poses several barriers that can be overcome by identifying and maximizing key facilitators of the process. Among them, patient education, a multidisciplinary team approach, and HaH-based postoperative care were crucial to the success of the program. Future studies should investigate the cost-effectiveness of telemedicine to assess potential cost savings, from reduced travel and wait times, and the impact on patient satisfaction.

154 Crossed cerebellar diaschisis in refractory epilepsy

BackgroundCrossed cerebellar diaschisis is the unilateral depression in functional activity of the cerebel- lar hemisphere, caused by a controlateral supratentorial lesion. The phenomenon arises from disruption of neuronal connections between the cerebrum and the cerebellum.Case reportWe present the case of a 42 year old woman with refractory epilepsy since early childhood. Her epilepsy is characterised by focal seizures with no impairment of awareness, and bilateral tonic- clonic seizures. She is currently on triple therapy with topiramate, gabapentin, and lacosamide. Seizure frequency varies with events occurring at least twice a week. MRI brain showed left mesial sclerosis, and PET CT demonstrated marked reduction in glucose uptake in the left temporal lobe, as well as reduction in uptake in the right cerebellar hemisphere. Scalp videotelemetry captured her events and demonstrated onset from the left fronto-temporal region.DiscussionThe epileptogenic focus was localised to the left fronto-temporal region. The PET CT demon- strated the phenomenon of crossed cerebellar diaschisis. It has been said that the phenomenon shows reversibility, but it is a poor prognostic factor, and it could result in cerebellar atrophy.englezou.chr@gmail.com

Susceptibility Weighted Imaging: An Effective Auxiliary Sequence That Enhances Insight Into the Imaging of Stroke

Aim: To evaluate the utility of susceptibility-weighted imaging (SWI) sequence in stroke imaging and assess supplemental information provided by SWI in an acute stroke scenario.Materials and methods: In this study, the appearance of cerebrovascular stroke on the SWI images were analyzed in 50 patients who presented with acute-onset neurological symptoms.Results: Brain MRI with SWI was performed on 50 patients presenting with acute neurological symptoms. The majority were males, 32/50 (64%) and 18/50 (36%) were females. Most of the patients were in the age group > 60 years (36%), followed by 50-60 years (22%). Most of the patients had bilateral pathology, 20 (40%). The majority of patients had supratentorial lesions 34 (68%). Among 50 patients, the majority of patients had arterial stroke 20 (40%) and cerebral venous sinus thrombosis (CVST) 20 (40%) followed by amyloid angiopathy five (10%), and five (10%) had hypertensive microhemorrhage. Among the 20 patients with arterial stroke, the majority had middle cerebral artery (MCA) thrombosis 10 (50%) and among the 20 patients with venous thrombosis, eight (40%) patients had hemorrhagic infarcts. SWI was better as compared to computed tomography (CT) (P<0.05) in the detection of hemorrhagic transformation of arterial infarct, cerebral hemorrhagic venous sinus thrombosis, hemorrhagic venous infarct, hypertensive microhemorrhage, and cerebral amyloid angiopathy.Conclusion: SWI is a useful imaging sequence that provides additional information on stroke patients. SWI requires only an additional three-four minutes to perform and can be easily incorporated into standard stroke protocol. SWI can identify various features such as hemorrhage, intraarterial thrombus, or concomitant microbleeds that are of prognostic value and affect therapeutic decisions.

False-positive results in transcranial motor evoked potentials for outcome prognostication during surgery for supratentorial lesions.

During monitoring of motor evoked potentials (MEP) elicited by transcranial electrical stimulation (TES) for prognostication of postoperative motor deficit, significant MEP changes without postoperative deterioration of motor function represent false-positive results. We aimed to investigate this phenomenon in a large series of patients who underwent resection of supratentorial lesions. TES was applied in 264 patients during resection of motor-eloquent supratentorial lesions. MEP were recorded bilaterally from arm, leg, and/ or facial muscles. The threshold criterion was applied assessing percentage increase in threshold level, which was considered significant if being > 20% higher on affected side than on the unaffected side. Subcortical stimulation was additionally applied to estimate the distance to corticospinal tract. Motor function was evaluated at 24h after surgery and at 3-month follow-up. Patients with false-positive results were analyzed regarding tumor location, tumor volume, and characteristics of the monitoring. MEP were recorded from 399 muscles (264 arm muscles, 75 leg muscles, and 60 facial muscles). Motor function was unchanged postoperatively in 359 muscles in 228 patients. Among these cases, the threshold level did not change significantly in 354 muscles in 224 patients, while it increased significantly in the remaining 5 muscles in 4 patients (abductor pollicis brevis in all four patients and orbicularis oris in one patient), leading to a false-positive rate of 1.1%. Tumor volume, opening the ventricle, and negative subcortical stimulation did not significantly correlate with false-positive results, while the tumor location in the parietal lobe dorsal to the postcentral gyrus correlated significantly (p = 0.012, odds ratio 11.2, 95% CI 1.8 to 69.8). False-negative results took place in 1.1% of cases in a large series of TES-MEP monitoring using the threshold criterion. Tumor location in the parietal lobe dorsal to the postcentral gyrus was the only predictor of false-positive results.

Monocentric clinical experience with frameless biopsy of supratentorial intraaxial lesions

Neuronavigated biopsy is a type of minimally invasive neurosurgical technique that allows careful planning and selection of one or more biopsy trajectories while preserving eloquent parenchymal areas by real-time tracking of the biopsy needle’s window. The aim of this study is to evaluate the technical and diаgnоstic efficacy of neuronavigated (frameless) biopsy in patients with supratentorial intraaxial lesions and to present the surgical technique used in these biopsies. A retrospective study has been conducted which includes the medical documentation of patients with intracranial lesions in whom neuronavigated frameless biopsy under general anesthesia was performed at the Clinic of Neurosurgery of University Hospital – “St. Marina” in Varna in the period from 2019 to 2021 year. 40 patients were included in the study. In 15 of the cases an isolated biopsy of the intraaxial lesion has been performed. In 25 of the cases a biopsy followed by an open excision of the intraaxial lesion has been performed. Dаtа were anаlyzed with SPSS versiоn 24. The reported diagnostic yield was 95%. Final intraoperative histological diagnosis was reached in 38 patients. In one patient (2.5%) the histological diagnosis was changed after immunohistochemical examination. In one patient (2.5%) the histological diagnosis was changed after excision of the lesion. One microbiological diagnosis was reached. No clinically significant complications or fatalities associated with the surgical technique were reported. Frаmeless biopsy in patients with suprаtentorial intraaxial lesions is a safe and effective procedure with high diagnostic value.

Eye Movement Abnormalities in Amyotrophic Lateral Sclerosis.

It is generally believed that eye movements are completely spared in amyotrophic lateral sclerosis (ALS). Although a series of eye movement abnormalities has been recognized in recent years, the findings are highly controversial, and bulbar disabilities should be considered in relation to eye movement abnormalities. The present study aimed to determine whether eye movement abnormalities are present in ALS and, if so, to investigate their characteristics and their association with bulbar disability in ALS patients. A total of 60 patients and 30 controls were recruited and underwent the standardized evaluations of the oculomotor system using videonystagmography. Square-wave jerks (OR: 16.20, 95% CI: 3.50–74.95, p < 0.001) and abnormal cogwheeling during smooth pursuit (OR: 14.04, 95% CI: 3.00–65.75, p = 0.001) were more frequently observed in ALS patients than in the control subjects. In subgroup analyses, square-wave jerks (OR: 26.51, 95% CI: 2.83–248.05, p = 0.004) and abnormal cogwheeling during smooth pursuit (OR: 6.56, 95% CI: 1.19–36.16, p = 0.031) were found to be more common in ALS patients with bulbar involvement (n = 44) than in those without bulbar involvement (n = 16). There were no significant differences in the investigated eye movement parameters between bulbar-onset (n = 12) and spinal-onset patients (n = 48). ALS patients showed a range of eye movement abnormalities, affecting mainly the ocular fixation and smooth pursuit systems. Our pioneering study indicates that the region of involvement could better indicate the pathophysiological essence of the abnormalities than the type of onset pattern in ALS. Eye movement abnormalities may be potential clinical markers for objectively evaluating upper brainstem or supratentorial cerebral lesion neurodegeneration in ALS.

Supratentorial Pediatric Midline Tumors and Tumor-like Lesions: Clinical Spectrum, Natural History and Treatment Options.

Childhood Central Nervous System tumors account for 25% of all pediatric tumors. Large availability and broadening of indications to imaging has made incidental findings more common. Among these, midline lesions have different clinical relevance depending on their intrinsic pattern of behaviour and on their specific location. In this narrative review we describe the natural history and treatment options of midline lesions in children.

Role of fetal MRI to diagnose abnormal cerebral ventricular system and associated fetal brain anomalies

BackgroundAbnormal cerebral ventricular system is one of the most common clinical indications for fetal MRI, mainly to detect other associated abnormalities that can be occult on prenatal ultrasonography. Although using ultrasound can identify most anomalies, MRI is known to be superior in identifying CNS anomalies as it has higher contrast resolution for brain parenchymal assessment added to the fact of being less affected by fetal positioning, oligohydramnios, maternal obesity, and reverberation artifacts. Fetal brain ventriculomegaly is defined as atrial width of > 10 mm on sonography, measured in the axial plane, at the level of the frontal horns, cavum septi pellucidi, and glomus of the choroid plexus perpendicular to the long axis of the lateral ventricle. One of the most important factors determining the fetal neurological outcome is the presence and severity of additional CNS anomalies that are better clarified by MRI. The aim of this study is to establish the role of fetal MRI in detecting the association between abnormal cerebral ventricular system and other CNS anomalies, correlation with the severity of ventriculomegaly and ventricle asymmetry.ResultsThirty pregnancies with fetal brain abnormal ventricular system were included in this study, 5 cases with isolated corpus callosum (CC) agenesis (16.666%); 2 cases with cystic lesions [one interhemispheric and the other dorsal] (6.666%) both associated with CC agenesis; 1 case with alobar holoprosencephaly (3.333%) associated with CC agenesis; 2 cases with semi-lobar holoprosencephaly (6.666%) [associated with CC agenesis and one of them is also associated with lissencephaly]; 3 cases with Dandy–Walker Malformation (DWM) (10%) [2 isolated and 1 associated with CC agenesis]; 3 cases with Dandy–Walker Variants (DWV) (10%) [1 isolated and 2 associated with CC agenesis]; 2 cases with Joubert syndrome (6.666%); 1 case isolated lissencephaly (3.333%); 4 cases of obstructive ventriculomegaly (13.333%) (1 of which associated with CC agenesis); 1 case of Arnold Chiari malformation type II (3.333%) associated with CC agenesis; 2 cases with meningoceles (6.666%) (occipital and parieto-occipital); 1 case with Mega cisterna Magna (3.333%); 1 case with anencephaly (3.333%); 1 case with right hemimegalencephaly (3.333%) (associated with frontal meningocele and CC agenesis); and 1 case with grade IV germinal matrix hemorrhage (3.333%). The pregnancies resulted in 20 births (66.66%), 2 died directly after birth (6.66%), 5 terminations (16.66%), and 3 intrauterine fetal deaths (IUFD) (10%). We found that the frequency of associated CNS anomalies was strongly related to the width of the ventricle. The association between CNS findings and ventricle width was particularly evident in sever ventriculomegaly. The greater the width of the ventricular system, the more the risk of associated CNS anomalies. Only one case showed diffusion restriction and was diagnosed to be of hemorrhagic nature. The relation between symmetry and degree of ventriculomegaly was found to be statistically insignificant (P = 0.115). Assessment of different fetal brain congenital anomalies was not significantly affected by the using of DWI sequence as it is a functional modality rather than being a tool for assessment of anatomical gross abnormalities.ConclusionsFetal MRI is an important adjuvant to US in cases of ventriculomegaly particularly those associated with complex CNS anomalies. The association between CNS findings and ventricular dilatation was particularly evident in sever ventriculomegaly. The greater the width of the ventricular system, the more the risk of associated CNS anomalies. Fetal MRI may also be helpful in doubtful cases that could be misdiagnosed as ventriculomegaly including holoprosencephaly, hydranencephaly, porencephaly, and various supratentorial cystic lesions. DWI confirms the diagnosis of hemorrhage.

Direction and magnitude of displacement differ between slowly expanding and non-expanding multiple sclerosis lesions as compared to small vessel disease.

Differentiating between multiple sclerosis (MS) and small vessel disease (SVD) lesions represents a key challenge in the day-to-day management of patients. We aimed to distinguish between MS and SVD by identifying the dynamics of lesion movement patterns between enlarging and contracting foci from two MRI time points. Standardized 3-Tesla 3-dimensional brain magnetic resonance imaging (MRI) studies were performed at two time points on enrolled MS and SVD patients. Selected supratentorial lesions were segmented and longitudinal changes in the direction of lesion displacement and magnitude along with the evolution of contracting and expanding T1-weighted and T2-weighted MS lesions were quantified based on lesion centroid positioning. Bayesian linear mixed effects regression models were constructed to evaluate associations between changes in lesion transitions and disease state. A total of 420 lesions were analyzed from 35 MS (female (F):22 (62.9%); median age (range):38years (y) (22-61), median disease duration:7.38y (0.38-20.99)) and 12 SVD patients (F:11 (100%); 54y (40-66)). MS T2-weighted lesions that increased in volume between MRI time points demonstrated movement toward the cortex (p = 0.01), whereas those that decreased in volume moved toward the center (p < 0.0001). Lesion volume changes related to SVD demonstrated no effect on movement direction over time. Both expanding (p = 0.03) and contracting (p = 0.01) MS lesions demonstrated greater distances between centroids when compared to SVD. Lesion dynamics may reveal distinct characteristics associated with the biology of disease while providing further insights into the behavior of inflammatory CNS disorders.

Remote cerebellar hemorrhage after supratentorial craniotomy: illustrative cases.

BACKGROUNDRemote cerebellar hemorrhage (RCH) is an extremely rare and potentially fatal complication after supratentorial craniotomy. However, the exact pathophysiological mechanism of RCH remains unclear, so clinicians often lack clinical experience in prevention, early diagnosis, and standardized treatment.OBSERVATIONSThe authors retrospectively analyzed data of patients who underwent surgery for supratentorial lesions at their center between 2012 and 2021. They identified 4 patients who developed RCH among 4,075 patients who underwent supratentorial craniotomy. All 4 patients were male, with an average age of 57.5 years. One RCH occurred after tumor resection, and the other 3 occurred after aneurysm clipping. One patient was asymptomatic and received conservative treatment with a favorable outcome. The remaining 3 patients underwent lateral ventricular drainage and/or suboccipital decompression; 2 died, and 1 recovered well.LESSONSThe authors believe that RCH should be considered as a multifactorial cause, and massive cerebrospinal fluid loss plays a key role in the development and progression of RCH. Asymptomatic RCH can be treated conservatively. However, in the case of conscious disturbance, hydrocephalus, and brain stem compression, surgery should be performed immediately. Early detection and individualized treatment would be helpful to avoid potentially fatal outcomes caused by RCH.

Internuclear ophthalmoplegia as a result of cerebral metastatic disease

This case demonstrates an acute case of internuclear ophthalmoplegia (INO) caused by cerebral metastasis from a small cell lung cancer, the only such case documented in the literature. A 54-year-old male presented to the emergency department for worsening headache and diplopia, secondary to INO. On further examination, a CT scan of the chest revealed a 6.1 × 4.8 × 6.8 cm solid mass in the right lower lung consistent with small-cell lung cancer. T2-weighted MRI exhibited bilateral supratentorial and infratentorial lesions interpreted as metastatic cancer. The patient's symptoms, including INO, were caused by the mass effect from the metastatic brain lesions.

MRI predictors for the conversion from contrast-enhancing to iron rim multiple sclerosis lesions

BackgroundIn multiple sclerosis (MS), iron rim lesions (IRLs) are characterized by progressive tissue matrix damage. Therefore, early identification could represent an interesting target for therapeutic intervention to minimize evolving tissue damage. The aim of this study was to identify magnetic resonance imaging (MRI) parameters predicting the conversion from contrast-enhancing to IRLs.MethodsWe retrospective identified MS patients scanned on the same 3 T MRI system presenting at least one supratentorial contrast-enhancing lesion (CEL) and a second MRI including susceptibility-weighted images after at least 3 months. On baseline MRI, pattern of contrast-enhancement was categorized as “nodular” or “ring-like”, apparent diffusion coefficient (ADC) maps were assessed for the presence of a peripheral hypointense rim. Lesion localization, quantitative volumes (ADC, lesion volume) and the presence of a central vein were assessed.ResultsEighty-nine acute contrast-enhancing lesions in 54 MS patients were included. On follow-up, 16/89 (18%) initially CELs converted into IRLs. CELs that converted into IRLs were larger and demonstrated significantly more often a ring-like contrast-enhancement pattern and a peripheral hypointense rim on ADC maps. Logistic regression model including the covariables pattern of contrast-enhancement and presence of a hypointense rim on ADC maps showed the best predictive performance (area under the curve = 0.932).DiscussionThe combination of a ring-like contrast-enhancement pattern and a peripheral hypointense rim on ADC maps has the ability to predict the evolution from acute to IRLs. This could be of prognostic value and become a target for early therapeutic intervention to minimize the associated tissue damage.

Effects of Galvanic Vestibular Stimulation on Subjective Visual Vertical and Sitting Balance in Patients with Stroke

ObjectiveThis study aimed to examine the effects of galvanic vestibular stimulation (GVS) on visual vertical cognition and sitting balance in stroke patients. Materials and MethodsPatients with unilateral supratentorial infarction and hemorrhagic lesions and healthy controls were recruited. Bipolar GVS was performed through the bilateral mastoid processes with an 1.5-mA electric current. Each participant received three stimulation patterns: right anode-left cathode, left anode-right cathode, and sham. The subjective visual vertical (SVV) and center of gravity positions in the sitting posture were measured in three groups of participants: patients with right hemisphere lesions, patients with left hemisphere lesions, and in healthy controls. Changes in the SVV and center of gravity positions before and during galvanic vestibular stimulation were assessed. ResultsIn each group, eight individuals were recruited for SVV measurements and nine individuals for center of gravity measurements. We found changes due to polarity of stimulation on the SVV and mediolateral changes in the center of gravity in the sitting position of patients with stroke, while there was no significant difference between groups or interaction of the two factors (polarity vs. group). ConclusionChanges in the visual vertical cognition and sitting balance occur during GVS in patients with stroke. GVS is a potential tool for ameliorating balance dysfunction in patients with stroke.

Relationship Between Cortical Excitability Changes and Cortical Thickness in Subcortical Chronic Stroke.

Ischemic stroke leads to excitability changes of the motor network as probed by means of transcranial magnetic stimulation (TMS). There is still limited data that shows to what extent structural alterations of the motor network might be linked to excitability changes. Previous results argue that the microstructural state of specific corticofugal motor tracts such as the corticospinal tract associate with cortical excitability in chronic stroke patients. The relationship between changes of cortical anatomy after stroke, as operationalized by means of decreases or increases in local cortical thickness (CT), has scarcely been addressed. In the present study, we re-analyzed TMS data and recruitment curve properties of motor evoked potentials and CT data in a group of 14 well-recovered chronic stroke patients with isolated supratentorial subcortical lesions. CT data of the stroke patients were compared to CT data of 17 healthy controls. Whole-brain and region-of-interest based analyses were conducted to relate CT data to measures of motor cortical excitability and clinical data. We found that stroke patients exhibited significantly reduced CT not only in the ipsilesional primary motor cortex but also in numerous secondary motor and non-motor brain regions, particularly in the ipsilesional hemisphere including areas along the central sulcus, the inferior frontal sulcus, the intraparietal sulcus, and cingulate cortices. We could not detect any significant relationship between the extent of CT reduction and stroke-related excitability changes of the motor network or clinical scores.

Brain Death Diagnosis in Primary Posterior Fossa Lesions.

New controversies have raised on brain death (BD) diagnosis when lesions are localized in the posterior fossa. The aim of this study was to discuss the particularities of BD diagnosis in patients with posterior fossa lesions. The author made a systematic review of literature on this topic. A supratentorial brain lesion usually produces a rostrocaudal transtentorial brain herniation, resulting in forebrain and brainstem loss of function. In secondary brain lesions (i.e., cerebral hypoxia), the brainstem is also affected like the forebrain. Nevertheless, some cases complaining posterior fossa lesions (i.e., basilar artery thrombotic infarcts, or hemorrhages of the brainstem and/or cerebellum) may retain intracranial blood flow and EEG activity. In this article, I discuss that if a posterior fossa lesion does not produce an enormous increment of intracranial pressure, a complete intracranial circulatory arrest does not occur, explaining the preservation of EEG activity, evoked potentials, and autonomic function. I also addressed Jahi McMath, who was declared braindead, but ancillary tests, performed 9 months after initial brain insult, showed conservation of intracranial structures, EEG activity, and autonomic reactivity to "Mother Talks" stimulus, rejecting the diagnosis of BD. Jahi McMath's MRI study demonstrated a huge lesion in the pons. Some authors have argued that in patients with primary brainstem lesions it might be possible to find in some cases partial recovery of consciousness, even fulfilling clinical BD criteria. This was the case in Jahi McMath.

Abstract No. : ABS2675: Effects of avoiding neuromuscular blocking agents during maintenance of anaesthesia for recovery characteristics in patients undergoing craniotomy supratentorial lesions: A randomised controlled trial.

Background & Aims:With the advent of newer anesthetic techniques, the utility of neuromuscular blocking agents (NMBA) in neuroanaesthesia seems dispensable. The aim was to determine whether NMBAs are required in patients undergoing supratentorial surgery when balanced anaesthesia with desflurane, dexmedetomidine and scalp block is used.Methods:Sixty patients with American society of anesthesiologists physical status I/II, aged between 18 & 60years were included. All patients received general anaesthesia along with desflurane, dexmedetomidine and scalp block. The patients were randomly allocated to receive no NMBA (groupA) or atracurium infusion to maintain a train of four count 2 (groupB). The two groups were compared with respect to haemodynamic stability, brain relaxation scores and recovery characteristics. Haemodynamic parameters and time taken to achieve Aldrete score >9 and secondary outcomes were analysed using Student’s t-test. Non-parametric data were analysed using the Mann-Whitney test.Results:The mean arterial pressure and intraoperative heart rate were comparable between the groups. However, in the postoperative period, heart rate remained higher in group B for 30 min after extubation (p=0.02). The brain relaxation scores were comparable among the groups (p=0.27).Tracheal extubation time, time taken for orientation and time required to reach Aldrete score >9 were comparable among the two groups.Conclusion:The present study suggested that balanced anaesthesia using desflurane, dexmedetomidine and scalp block can preclude the use of neuromuscular blocking agents in patients undergoing supratentorial surgery under intense haemodynamic monitoring.

Crossed cerebellar diaschisis in Alzheimer's disease.

Crossed cerebellar diaschisis (CCD) is characterized by hypometabolism and hypoperfusion on molecular imaging in the cerebellum due to a supratentorial lesion on the contralateral side. CCD is a well-established phenomenon in acute or subacute conditions such as infarction but it has been less well described in chronic conditions such as neurodegenerative dementias. Here, we investigate CCD in a large sample of 830 people meeting research criteria for Alzheimer's disease (AD) using [18F]fluorodeoxyglucose-positron emission tomography (FDG-PET). This study is based on FDG-PET data collected at baseline as part of two large-scale Phase III clinical trials of a novel tau aggregation inhibitor medication, methylthioninium in mild to moderate AD participants. Quantification of FDG-PET hypometabolism was carried out using standardized uptake value ratio (SUVR), with the pons as the comparison region. SUVR was compared in different regions of interest between the right and left hemispheres of the brain and cerebellum in people with mild AD (Mini-Mental State Examination score ≥ 20). Comparison of SUVR in different brain regions demonstrated significant differences in the temporal, occipital and cerebellar cortices. Right and left asymmetry was noted with lower SUVR in the left temporal and occipital regions, whereas SUVR was lower in the right side of the cerebellum. Here, we found robust evidence of CCD in a large sample of people with AD, a chronic neurodegenerative condition. The presence of this phenomenon in AD opens up a new avenue of research in AD pathogenesis and has the potential to change future diagnostic and therapeutic strategies.

The central vein sign is present in most infratentorial multiple sclerosis plaques

Background and purposeThere is growing evidence supporting the presence of the central vein sign (CVS) in the supratentorial brain as an imaging biomarker for multiple sclerosis (MS) diagnosis. Recently, using optimized susceptibility-weighted angiography (SWAN-venule), we detected CVS in 86% of supratentorial white matter lesions (WMLs) in the clinical setting on images obtained in a 3T MRI scanner. Despite the relevance of the infratentorial compartment, CVS prevalence in infratentorial MS plaques has not been investigated in detail. Our objective was to determine the proportion of MS infratentorial lesions showing CVS positivity. Materials and methodsWe included subjects with MS and other brain diseases showing at least one infratentorial lesion larger than 3 mm on 3D-FLAIR. Patients were scanned in a 3T MRI scanner (GE Medical Systems, discovery-MR750), applying a comprehensive protocol including post-contrast 3D-FLAIR and SWAN-venule sequences. CVS presence was confirmed by two trained raters. ResultsThirty MRIs of subjects with MS were analyzed. One hundred and one infratentorial lesions were detected on FLAIR, and 86% were centered by a vein. Fifteen MRIs from the non-MS group were analyzed, 19 lesions were visible ion FLAIR and 16% were positive for the CVS. ConclusionsSWAN-venule detects infratentorial lesions and highlights the central vein in MS plaques at 3T MRI. As occurs in the supratentorial brain, most infratentorial lesions are perivenular.

Associations Between Stroke Localization and Delirium: A Systematic Review and Meta-Analysis

ObjectivesDelirium is common among patients with acute stroke and associated with worse outcomes. However, it is unclear which stroke locations or types are most associated with delirium. Materials and MethodsWe systematically reviewed studies of patients with acute stroke that reported stroke locations and types by delirium status. We included papers in any language, through a combined search from January 2010 to June 2021. Case studies with less than 20 patients, case-control studies, and randomized controlled trials were excluded. MEDLINE, EMBASE, PsycINFO, CINAHL, and Alois databases were searched. Pooled relative risks were calculated using bivariate random effects models or network meta-analysis. Methodological quality was assessed across 8 factors. Results31 patient samples representing 8329 patients were included. Delirium was more common in patients with supratentorial lesions than infratentorial (RR [Relative Risk] 2.01, CI [Confidence Interval] 1.49-2.72); anterior circulation lesions than posterior (RR 1.41, CI 1.13-1.78); and cortical lesions than subcortical (RR 1.54, CI 1.25-1.89). Stroke side was not associated with delirium (right vs. left: RR 0.99, CI 0.77-1.28). Delirium was more common in patients with hemorrhagic strokes than ischemic (RR 1.74, CI 1.42-2.11) and patients with preexisting qualitative atrophy (RR 1.66, CI 1.21-2.27). ConclusionSeveral brain localizations and types of strokes were associated with delirium. Conclusions were in part limited by the heterogeneity of studies and broad or qualitative lesion descriptions. These results may assist in anticipating the risk of delirium in acute stroke and highlight brain networks and pathologies that may be involved in the pathophysiology of delirium.