Risk Assessment by Pre-surgical Tractography in Left Hemisphere Low-Grade Gliomas.

Background: Tracking the white matter principal tracts is routinely typically included during the pre-surgery planning examinations and has revealed to limit functional resection of low-grade gliomas (LGGs) in eloquent areas. Objective: We examined the integrity of the Superior Longitudinal Fasciculus (SLF) and Inferior Fronto-Occipital Fasciculus (IFOF), both known to be part of the language-related network in patients with LGGs involving the temporo-insular cortex. In a comparative approach, we contrasted the main quantitative fiber tracking values in the tumoral (T) and healthy (H) hemispheres to test whether or not this ratio could discriminate amongst patients with different post-operative outcomes. Methods: Twenty-six patients with LGGs were included. We obtained quantitative fiber tracking values in the tumoral and healthy hemispheres and calculated the ratio (HIFOF-TIFOF)/HIFOF and the ratio (HSLF-TSLF)/HSLF on the number of streamlines. We analyzed how these values varied between patients with and without post-operative neurological outcomes and between patients with different post-operative Engel classes. Results: The ratio for both IFOF and SLF significantly differed between patient with and without post-operative neurological language deficits. No associations were found between white matter structural changes and post-operative seizure outcomes. Conclusions: Calculating the ratio on the number of streamlines and fractional anisotropy between the tumoral and the healthy hemispheres resulted to be a useful approach, which can prove to be useful during the pre-operative planning examination, as it gives a glimpse on the potential clinical outcomes in patients with LGGs involving the left temporo-insular cortex.

Intracranial Meningiomas in the Elderly: Clinical, Surgical and Economic Evaluation. A Multicentric Experience.

Meningioma is one of the most common intracranial tumors. It is benign and slow growing in the majority of cases. Given the increase in life expectancy and the number of radiological tests performed, the incidence in the elderly population (≥65 years) is continuously increasing. The surgical outcomes and prognostic factors in this age group are unclear. A retrospective analysis of all the patients treated for intracranial meningiomas in two different Italian institutions was performed. The clinical, radiological, surgical and follow-up data were retrospectively reviewed. Statistical analyses were performed to identify relationships between factors and outcomes. We also carried out an economic analysis. We analyzed 321 patients with intracranial meningioma. The mean age was 72.6 years (range, 65-90), with a female predominance (F/M, 1.41). Pre-operative deficits, cognitive impairment and seizures (p < 0.001) were associated with a worse post-operative Karnofsky performance scale (KPS) score (<80). A high pre-operative KPS score was associated with a good clinical and neurological outcome (p < 0.001). Being aged between 65 and 74 years, low surgical timing and Simpson removal grades of I and II were associated with a good outcome (p < 0.001). The length of hospitalization was significantly related to the outcome (p < 0.001). The complication rate was 14.3%. At 6-month follow-up, the mortality rate was 2.5%. The average cost was higher in patients with a pre-operative KPS score lower than 80. The outcome of intracranial-meningioma resection in elderly individuals is favorable when the pre-operative KPS score is >80. Treatment should be patient-specific, and additional factors should be considered. Patients with poor pre-operative clinical conditions might benefit from a combined strategy with partial resection and radiosurgery in order to reduce surgical timing and the complication rate.

Multimodal Assessment Shows a Mostly Preserved Cognitive Status in Incidentally Discovered Low Grade Gliomas: A Single Institution Study.

Incidentally discovered low-grade gliomas (iLGGs) are poorly reported in the literature. Still less is known about iLGG patients' neuropsychological profile: It is unclear whether iLGG patients are cognitively proficient, thus further confirming the concept of asymptomatic. From our monoinstitutional cohort of 332 patients operated for LGG from 2000 to 2017 we selected those who underwent a neuropsychological testing (n = 217, from 2008 to 2017), and identified 24 young (mean age 38.5 ± 1.06) patients with iLGGs (16 of 24, left hemisphere iLGGs, 8 of 24 right hemisphere iLGGs). The maximum lesions overlap occurred in the left inferior frontal gyrus and in the right anterior cingulate/superior medial frontal gyrus. Patients were cognitively preserved except mild to borderline difficulties in a few of them. The analysis of the equivalent scores (a score laying below or equal to the external nonparametric tolerance limit of adjusted scores corresponding to 0, 1, 2 and 3 are intermediate) highlighted the presence of additional borderline performances. Molecular class correlated with a normal function at visual-spatial intelligence (p = 0.05) and at spatial short-term memory (p = 0.029). Results indicate that at this time of tumor growth, patients' cognitive abilities are still functional, but are slowly approaching the borderline level.

The role of perfusion and diffusion MRI in the assessment of patients affected by probable idiopathic normal pressure hydrocephalus. A cohort-prospective preliminary study.

BACKGROUND: Invasive tests measuring resistance to cerebral spinal fluid (CSF) outflow and the effect of temporary drainage of CSF are used to select candidates affected by idiopathic normal pressure hydrocephalus (iNPH) for shunt surgery. Neither test, however, completely excludes patients from treatment. Perfusion and diffusion magnetic resonance imaging (MRI) are non-invasive techniques that might be of value in selecting patients for surgical treatment and understanding brain changes in iNPH patients. The aim of this study was to understand the role of perfusion and diffusion MRI in selecting candidates for shunt surgery and to investigate the relationship between cerebral perfusion and possible microstructural changes in brain tissue before and after invasive tests, and after ventricular-peritoneal (VP) shunt implantation, to better clarify pathophysiological mechanisms underlying iNPH. METHODS: Twenty-three consecutive patients with probable iNPH were included in this study. Patients underwent a clinical and neuroradiological evaluation before and after invasive tests, and after surgery. Only patients who showed a positive result in at least one of the invasive tests were submitted for VP shunt implantation. Perfusion and diffusion magnetic resonance imaging (MRI) was performed before and after invasive tests and after shunt surgery. RESULTS: Thirteen patients underwent surgery and all showed clinical improvement after VP shunt implantation and a significant increase in perfusion in both periventricular white matter (PVWM) and basal ganglia (BG) regions. The 10 patients that did not have surgery showed after invasive tests, a significant reduction in perfusion in both PVWM and BG regions. Comparing the changes in perfusion with those of diffusion in positive patients we found a significant positive correlation in BG and a significant inverse correlation in PVWM area. CONCLUSIONS: Perfusion MRI is a non-invasive technique that could be useful together with invasive tests in selecting patients for surgical treatment. Furthermore, the relationship between perfusion and diffusion data could better clarify pathophysiological mechanisms underlying iNPH. In PVWM area we suggest that interstitial edema could reduce microvascular blood flow and interfere with the blood supply to these regions. In BG regions we suggest that a chronic hypoxic insult caused by blood hypo-perfusion produces a chronic cytotoxic edema. Both in PVWM and in BG regions, pathophysiological mechanisms could be modified after VP-shunt implantation.

Survey on current cognitive practices within the European Low-Grade Glioma Network: towards a European assessment protocol.

BACKGROUND: The European Low-Grade Glioma network indicated a need to better understand common practices regarding the managing of diffuse low-grade gliomas. This area has experienced great advances in recent years. METHOD: A general survey on the managing of diffuse low-grade gliomas was answered by 21 centres in 11 European countries. Here we focused on specific questions regarding perioperative and intraoperative cognitive assessments. RESULTS: More centres referred to the same speech and language therapist and/or neuropsychologist across all assessments; a core of assessment tools was routinely used across centres; fluency tasks were commonly used in the perioperative stages, and object naming during surgery; tasks that tapped on attention, executive functions, visuospatial awareness, calculation and emotions were sparsely administered; preoperative assessments were performed 1 month or 1 week before surgery; timing for postoperative assessments varied; finally, more centres recommended early rehabilitation, whenever needed. CONCLUSIONS: There is an emerging trend towards following similar practices for the management of low-grade gliomas in Europe. Our results are descriptive and formalise current discussions in our group. Also, they contribute towards the development of a European assessment protocol.

Treatment of recurrent high-grade gliomas with GliaSite brachytherapy: a prospective mono-institutional Italian experience.

AIMS AND BACKGROUND: The present study evaluated toxicity, local control, and survival in patients with relapsed high-grade glioma after surgery and external beam radiation therapy and treated with re-operation and GliaSite brachytherapy. METHODS: Between 2006 and 2008, 15 patients with recurrent high-grade glioma underwent re-operation and GliaSite brachytherapy. Ten patients were males and 5 females. Median age was 40 years (range, 20-71). Karnofsky performance status was ≥70. All patients but one received GliaSite irradiation of the surgical cavity wall at the dose of 4500 cGy at a depth of 1 cm. RESULTS: No severe acute side effects were observed during GliaSite brachytherapy. Pathologically documented, symptomatic late radiation necrosis was observed in 3 patients (20%); 2 subsequently died of further complications. Two patients were alive at a median follow-up 13 months (range, 1-30). Median overall survival after GliaSite brachytherapy was 13 months. CONCLUSIONS: Patients with recurrent high-grade glioma can be treated with additional surgery and GliaSite brachytherapy, delivering 4500 cGy at 1 cm depth without significant acute side effects but with a significant rate (20%) of late radiation necrosis, resulting in 13% of treatment-related deaths. Compared with the literature, survival results in our study appear to be satisfactory, but they may be related to patient selection criteria. Re-intervention followed by GliaSite brachytherapy should not be offered as a standard treatment for recurrent high-grade glioma, because of the high rate of late complications, treatment-related deaths, and high treatment costs.

Two qualitatively different impairments in making rotation operations.

It is widely recognized that mental rotation is a cognitive process which engages a distributed cortical network including the frontal, premotor and parietal regions. Like other visual-spatial transformations it could require operations on both metric and categorical spatial representations. Previous reports have implicated respectively the right hemisphere being involved in the metric processing and the left hemisphere in the categorical processing. By using a modified version of the Bricolo et al.'s task (2000), we attempted to establish the cortical regions relevant for the categorical and metric aspects of mental rotation transformations. Two groups of patients were found to be impaired in our study, namely the left prefrontal and the right parietal. In particular, whereas the right parietal group made poor use of categorical information, the left prefrontal patients showed a broader mental rotation impairment with a significant number of metric errors. The results are discussed in terms of the model of Kosslyn et al. (1989) about the possible mental transformation impairments following brain lesions.