Intravoxel incoherent motion magnetic resonance imaging in the assessment of brain microstructure and perfusion in idiopathic normal-pressure hydrocephalus

PURPOSE

To determine the relationship between intravoxel incoherent motion (IVIM) MRI parameters and clinical changes post-tap test (TT) in idiopathic normal-pressure hydrocephalus (iNPH) patients.

METHODS

Forty-four probable iNPH patients underwent 3 T MRI before and after TT. IVIM parameters were calculated from eight different bilateral regions of interest in basal ganglia, centrum semiovale, and corona radiata. Patients were categorized based on TT response into positive (group 1) and negative (group 2) groups. A Welch two-sample t-test was used to compare differences in D, D*, f, and ADC between the two groups, while a paired t-test was employed to assess the changes within each group before and after TT. These parameters were then correlated with clinical results.

RESULTS

In the lenticular and thalamic nuclei, D value was significantly lower in the group 1 compared to group 2 both pre- and post-TT (p = 0.002 and p = 0.007 respectively). Post-TT, the positive response group exhibited a notably reduced D* value (p = 0.012) and significantly higher f values (p = 0.028). In the corona radiata and centrum semiovale, a significant post-TT reduction in D* was observed in the positive response group (p = 0.017). Within groups, the positive response cohort showed a significant post-TT increase in ADC (p < 0.001) and a decrease in D* (p = 0.007).

CONCLUSION

IVIM permits the acquisition of important non-invasive information about tissue and vascularization in iNPH patients. Enhanced perfusion in the lenticular and thalamic nuclei may suggest the role of re-established microvascular and glymphatic pathways, potentially elucidating the functional improvement in motor function after TT in iNPH patients.

Clinical applicability of arterial spin labeling magnetic resonance imaging in patients with possible idiopathic normal pressure hydrocephalus: A prospective preliminary study

PURPOSE

idiopathic Normal Pressure Hydrocephalus (iNPH) patients have a global reduction of cerebral blood flow (CBF) and Arterial Spin Label (ASL) MRI allows a global evaluation of CBF without the injection of contrast agents. This work aims to assess the qualitative evaluation agreement of ASL CBF colored maps between different neuroradiologists and by correlating these data to the Tap Test.

METHODS

Thirty - seven patients with the diagnosis of possible iNPH were consecutively submitted to a diagnostic MRI on a 1.5 Tesla Magnet before and after the lumbar infusion test and the Tap Test. Twenty - seven patients improved after the Tap Test and were addressed to surgery while 10 patients did not improve. All the MRI examinations included a 3D-Pulsed ASL sequence. Two different neuroradiologists independently reviewed all ASL images. They were asked to give a score (0 not improved; 1 improved) to global perfusion image quality by comparing ASL images obtained after the Tap Test to those obtained before. Comparison between inter- and intra-reader qualitative scores were performed with Cohen's kappa.

RESULTS

Inter-reader agreement between the two neuroradiologists showed that qualitative scores were attributed similarly by two readers (k = 0.83). This technique has a good PPV (90.5 %; CI 95 %, 72.7-97.1 %), NPV (50 %; CI 95 %, 34.1-65.6 %), SN (70.37 %; CI 95 %, 49.8-86.2 %) SP (80 %; CI 95 %, 44.4-97.5 %) and accuracy (73 %; CI 95 %, 55.9-86.2 %) when considered in the setting of possible iNPH patients.

CONCLUSION

ASL-MRI seems to be a promising non-invasive technique in the preoperative selection of patients affected by possible iNPH.

MDS-UDPRS-III in the diagnosis of idiopathic Normal Pressure Hydrocephalus and identification of candidates for Ventriculo-Peritoneal Shunting surgery. Results from a retrospective large cohort of patients

OBJECTIVES

To evaluate the entity of extrapyramidal signs, characterize them and evaluate the dynamics of change by the mean of MDS-UPDRS-III in iNPH patients after the TT to determine if this tool may help the diagnosis of iNPH and the identification of candidates for Ventriculo-Peritoneal Shunting.

MATERIALS AND METHODS

We retrospectively collected data from 120 patients with the initial diagnosis of possible iNPH; they underwent neurological examination by the means of MDS-UPDRS-III and other scales before and after Tap Test (TT). They were then classified as defined iNPH (57), probable iNPH (35), and NOT-iNPH (28) based on the clinical response after the Tap Test and VPS.

RESULTS

After the Tap Test, defined and probable iNPH groups improved by 3.35 (2.57-4.12, p < 0.001) and 3.43 (2.43-4.4, p < 0.001) points on MDS-UPDRS-III respectively; NOT-iNPH did not improve significantly on MDS-UPDRS-III and on any other variable studies. Defined iNPH also shifted significantly from asymmetric prevalence of symptoms to a more symmetric form (from 70% before to 57% after).

CONCLUSION

extrapyramidal signs improved significantly after the Tap Test in definite and probable iNPH patients. MDS-UPDRS-III may be a useful complementary tool in the diagnosis of iNPH and identification of candidates for Ventriculo-Peritoneal Shunting.

Resting-state functional-MRI in iNPH: can default mode and motor networks changes improve patient selection and outcome? Preliminary report

BACKGROUND

Idiopathic normal pressure hydrocephalus (iNPH) is a progressive and partially reversible form of dementia, characterized by impaired interactions between multiple brain regions. Because of the presence of comorbidities and a lack of accurate diagnostic and prognostic biomarkers, only a minority of patients receives disease-specific treatment. Recently, resting-state functional-magnetic resonance imaging (rs-fMRI) has demonstrated functional connectivity alterations in inter-hemispheric, frontal, occipital, default-mode (DMN) and motor network (MN) circuits. Herein, we report our experience in a cohort of iNPH patients that underwent cerebrospinal fluid (CSF) dynamics evaluation and rs-fMRI. The study aimed to identify functional circuits related to iNPH and explore the relationship between DMN and MN recordings and clinical modifications before and after infusion and tap test, trying to understand iNPH pathophysiology and to predict the best responders to ventriculoperitoneal shunt (VPS) implant.

METHODS

We prospectively collected data regarding clinical assessment, neuroradiological findings, lumbar infusion and tap test of thirty-two iNPH patients who underwent VPS implant. Rs-fMRI was performed using MELODIC-ICA both before and after the tap test. Rs-fMRI data of thirty healthy subjects were also recorded.

RESULTS

At the baseline, reduced z-DMN and z-MN scores were recorded in the iNPH cohort compared with controls. Higher z-scores were recorded in more impaired patients. Both z-scores significantly improved after the tap test except in subjects with a low resistance to outflow value and without a significant clinical improvement after the test. A statistically significant difference in mean MN connectivity scores for tap test responders and non-responders was demonstrated both before (p = 0.0236) and after the test (p = 0.00137). A statistically significant main effect of the tap test on DMN connectivity after CSF subtraction was recorded (p = 0.038).

CONCLUSIONS

Our results suggest the presence of a partially reversible plasticity functional mechanism in DMN and MN. Low values compensate for the initial stages of the disease, while higher values of z-DMN were recorded in older patients with a longer duration of symptoms, suggesting an exhausted plasticity compensation. The standardization of this technique could play a role as a non-invasive biomarker in iNPH disease, suggesting the right time for surgery. Trial Registration Prot. IRB 090/2021.

Primary Leptomeningeal Medulloblastoma in Adults: A Diagnostic Challenge-Case Report and Systematic Review

Primary leptomeningeal medulloblastoma (PL-MB) in adults is a rare disease with a severe prognosis. A 35-year-old woman presented with headaches, diplopia, and gait ataxia, with triventricular hydrocephalus and descent of the cerebellar tonsils beyond the foramen magnum. Endoscopic third ventriculostomy was performed. Six months later, headaches recurred. Dilatation of the supratentorial ventricular system and massive cerebellar swelling without contrast-enhancing nodularities were reported. Occipitocervical decompression with duraplasty was performed. A bioptic diagnosis of PL-MB was made. Craniospinal irradiation and chemotherapy were administered. After 18 months, no recurrence was observed. Few cases of PL-MB have been reported: patients die before treatment or within a few days after surgery. Our long-term survival could be ascribable to a slow clinical presentation and an early diagnosis that allowed surgical treatment and the administration of a combined chemoradiotherapy protocol. Cerebellar swelling, even without associated enhancing lesions, with or without hydrocephalus, should be a neuroradiological alarm sign, and PL-MB should be considered.

Image-guided LINAC radiosurgery in hypothalamic hamartomas

Introduction

Hypothalamic hamartomas (HH) are developmental malformations that are associated with mild to severe drug-refractory epilepsy. Stereotactic radiosurgery (SRS) is an emerging non-invasive option for the treatment of small and medium-sized HH, providing good seizure outcomes without neurological complications. Here, we report our experience treating HH with frameless LINAC SRS.

Materials and methods

We retrospectively collected clinical and neuroradiological data of ten subjects with HH-related epilepsy that underwent frameless image-guided SRS.

Results

All patients underwent single-fraction SRS using a mean prescribed dose of 16.27 Gy (range 16–18 Gy). The median prescription isodose was 79% (range 65–81 Gy). The mean target volume was 0.64 cc (range 0.26–1.16 cc). Eight patients experienced complete or near complete seizure freedom (Engel class I and II). Five patients achieved complete seizure control within 4 to 18 months after the treatment. Four patients achieved Engel class II outcome, with stable results. One patient had a reduction of seizure burden superior to 50% (Engel class III). One patient had no benefit at all (Engel class IV) and refused further treatments. Overall, at the last follow-up, three patients experience class I, five class II, one class III and one class IV outcome. No neurological complications were reported.

Conclusions

Frameless LINAC SRS provides good seizure and long-term neuropsychosocial outcome, without the risks of neurological complications inherently associated with microsurgical resection.

Long-Standing Overt Ventriculomegaly in Adults (LOVA): Diagnostic Aspects, CSF Dynamics with Lumbar Infusion Test and Treatment Options in a Consecutive Series with Long-Term Follow-Up

BACKGROUND

Long-standing overt ventriculomegaly in adults is a chronic form of hydrocephalus without a clear pathophysiological description and a consensus about the treatment. We present the results of endoscopic third ventriculostomy (ETV) in a consecutive series with a mean follow-up of 79 ± 23 months, highlighting how the preoperative lumbar infusion test could facilitate understanding the pathophysiology of the disease.

METHODS

We retrospectively collected data regarding clinical assessment, neuroradiological findings, and preoperative lumbar infusion tests in 22 symptomatic patients.

RESULTS

In the majority of cases, patients reported imbalance and gait disorders, and 8 subjects had headaches. The preoperative lumbar infusion test demonstrated a mean opening pressure of 13.95 ± 2.88 mm Hg, with plateau values ranging from 22 to 39 mm Hg. The resistance to outflow was 11.21 ± 2.00 mm Hg/mL/min. After the procedure, all patients reported improvement or halted progression in their presenting symptoms, whereas no significant reduction was demonstrated in Evans' index. One subject underwent a second ETV procedure after more than 2 years because of the failure of the endoscopic approach.

CONCLUSIONS

A progressive exhaustion of brain compliance plays an important role in explaining the dichotomy between severe ventriculomegaly and mild clinical symptoms in patients with long-standing overt ventriculomegaly in adults. The role of the aqueductal stenosis as a diagnostic criterion might be reconsidered. The preoperative infusion test data support this observation. Preoperative assessment should include not only clinical and neuroradiological evaluation but also the study of cerebrospinal fluid dynamics. ETV should be considered the treatment of choice because of its safety and efficacy. Long-term follow-up is mandatory.

Cubik system: maximizing possibilities of in-house computer-guided surgery for complex craniofacial reconstruction

Craniofacial reconstruction represents a major challenge due to the complex anatomical morphology. Although implant production has often been outsourced to external companies, in-house planning and manufacturing has developed in many centres. This note introduces a conceptualized modular mould system to perform any desired craniofacial reconstruction, named 'Cubik', inspired by the famous Rubik's cube. A sophisticated virtual process is described that simulates realistic cranio-orbital resections, and the workflow to create multi-component moulds in order to achieve intraoperatively moulded implants is presented. The description focuses on the appropriate definition of interfaces between the subdivision surfaces of the planned implant, which is the key element to successful design and function of the moulds during surgery and is the peculiarity of the Cubik system. The use of Cubik does not prolong the overall duration of surgery, and it appears to be a very versatile tool, allowing personalized implants with different morphology to be created, which are suitable to cover every potential defect of the skull and the orbital region. This study extends the potential of in-house production, allowing highly accurate implantable craniofacial implants to be fabricated, and in the future this might represent a solution to achieve in-house replacement of other segments of the facial skeleton.

Risk Factors of Persistent Hydrocephalus in Children with Brain Tumor: A Retrospective Analysis

OBJECT

Hydrocephalus is one of the main complications of brain tumors in children, being present in about 50% of cases at the time of the tumor diagnosis and persisting up to 10-40% of cases after surgical resection. This is a single-institution retrospective study on the variables that may predict the need for treatment of persistent hydrocephalus in pediatric patients presenting with a brain tumor.

METHODS

Retrospective case note review of 43 newly diagnosed brain tumors in children referred between April 2012 and January 2018 to our regional pediatric neuro-oncology service was carried out. Diagnosis of hydrocephalus was carried out using both preoperative and postoperative MRI to determine Evans' index (EI) and the fronto-occipital horn ratio (FOHR) from each scan. Simple logistic regression was used to analyze categorical variables as appropriate. A p value <0.05 was considered significant.

RESULTS

Forty-three children were analyzed, 26 males and 17 females with a median age at diagnosis 10.4 years (IQR: 5.2-13.5). Hydrocephalus was present in 22/43 children (51%) preoperatively; in 8/22 children (36%) with hydrocephalus undergoing tumor resection, hydrocephalus persisted also in the postoperative period. An EI >0.34 (p = 0.028) and an FOHR >0.46 (p = 0.05) before surgery were associated with a higher prevalence of persistent hydrocephalus and therefore to the need for a cerebrospinal fluid drain device in the postoperative phase.

CONCLUSION

Preoperative identification of children at risk for developing persistent hydrocephalus would avoid delays in planning the permanent cerebrospinal fluid drain devices. This study finds that an EI >0.34 and an FOHR >0.46 at diagnosis could impact on the therapeutic management of children with hydrocephalus associated with brain tumors. Prospective and larger-scale studies are needed to standardize this approach.

Late-onset occlusion of the Monro foramina after endoscopic third ventriculostomy in adults: Case discussion and review of the literature

Background:

Few cases of adult idiopathic occlusion of the foramen of Monro (AIOFM) are described in the literature. The diagnosis of AIOFM after an endoscopic procedure is even more infrequent.

Case Description:

We described the case of a 50-year-old woman who developed bilateral membranous occlusion of both Monro foramina 20 years after an endoscopic third ventriculostomy (ETV) for triventricular hydrocephalus due to an aqueductal stenosis. The patient underwent an endoscopic treatment (left foraminoplasty and septostomy) to check the patency of the stoma on the floor of the third ventricle. After the endoscopic procedure, the symptoms improved and the postoperative magnetic resonance imaging (MRI) demonstrated the resolution of the biventricular hydrocephalus.

Conclusion:

Bilateral occlusion of both FM with consequent bilateral lateral ventricles enlargement is an extremely rare condition, especially if we consider the cases of biventricular hydrocephalus after endoscopic procedures. In our opinion, an endoscopic approach should be attempted as first choice procedure, avoiding any intraventricular stent or shunt placement.

Supratentorial Cavernous Malformations Involving the Corticospinal Tract and Sensory Motor Cortex: Treatment Strategies, Surgical Considerations, and Outcomes

BACKGROUND

Cavernous malformations (CMs) are congenital malformations and may be located anywhere in the brain. We present a series of CMs located close to or inside of the motor-sensory cortex or corticospinal tract (CST) with clinical onset due to hemorrhage or mass effect. In such cases, surgery becomes an acceptable option.

OBJECTIVE

To evaluate the role of diffusion tensor imaging (DTI), functional-magnetic-resonance imaging (fMRI), intraoperative neurophysiological monitoring, neuronavigation, and brain-mapping and the clinical results of surgical treatment of CMs in this critical location.

METHODS

The study included 54 patients harboring 22 cortical and 32 deep locations. This series was distinct because in group I, where the DTI was not obtained, and in the group II, where this evaluation was performed.

RESULTS

The postoperative permanent morbidity rate was 4% in the historical group for the deeper CMs, and there was no morbidity in the second group. DTI and fMRI permitted us to estimate the distance between the CMs and both the cortical activation cluster and the pyramidal tract. These data, in addition to intraoperative mapping and monitoring, made it necessary for us to perform a partial resection in 2 cases in the second series.

CONCLUSION

CMs are congenital lesions and CST fibers can run directly on their surface. Integration of fMRI and DTI data with intraoperative functional monitoring and direct cortical and subcortical mapping are mandatory to accomplish an optimal resection, tailoring the best surgical approach to the acceptable morbidity. A subtotal resection could be considered an option for deep locations.

A novel approach to skull-base and orbital osteotomies through virtual planning and navigation

OBJECTIVE

Computer-assisted planning of osteotomy lines, coupled with navigation-guided performance of planned osteotomies, is a highly innovative approach to skull-base and orbital surgery. The aim of this pilot study is to provide an assessment of the accuracy of this novel approach in guiding the correct positioning of osteotomy lines in frontal, temporal, and orbital regions, defining the agreement between the spatial position of the planned and performed osteotomies.

METHODS

Fifteen patients with orbital, frontal sinus, and lateral skull-base diseases underwent virtual surgical planning. Osteotomies to access the orbit, frontal sinus, and lateral skull base were planned on computer tomography-based three-dimensional models. The planned osteotomies were reproduced on the operating field using a navigation system. The positions of the performed and planned osteotomies were compared. The results were described as the mean positional difference between planned and performed osteotomies and as Lin's concordance coefficient, and Bland-Altman limits of agreement were also defined.

RESULTS

The overall mean difference was 0.719 mm (95% confidence interval [CI]: 0.472 to 0.965 mm). Overall, Lin's concordance coefficient was 0.997 (95% CI: 0.996 to 0.998), and overall Bland-Altman limits of agreement ranged from -1.407 to 2.844 mm. The smallest mean difference (0.587 mm, 95% CI: 0.244 to 0.931 mm) was calculated in the orbit group, whereas the highest mean difference (0.904 mm, 95% CI: 0.428 to 1.379 mm) was described in the lateral skull-base group.

CONCLUSION

This study's results support the use of this novel planning and navigation protocol for guiding osteotomy in anterior and lateral skull-base surgery, providing a clinical validation of this technique.

LEVEL OF EVIDENCE

4 Laryngoscope, 00:1-9, 2018 Laryngoscope, 129:823-831, 2019.

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.

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.

Comparison of the molecular profile of brain metastases from colorectal cancer and corresponding primary tumors

AIM

Little is known about molecular biology of brain metastasis (BM) from colorectal cancer and its concordance with matched primary tumors.

MATERIALS & METHODS

We identified 56 consecutive colorectal cancer patients who underwent neurosurgical resection of BM. Tumor samples were tested for KRAS, NRAS, BRAF and PIK3CA. The molecular profile of the brain lesion was compared with the corresponding primary tumor.

RESULTS

The molecular profile concordance rate was 95.1%. Median survival after neurosurgery was 5.5 months (95% CI: 4.7-6.3); median overall survival was 24.0 months (95% CI: 15.6-32.4).

CONCLUSION

In this cohort, we report a high frequency of KRAS mutations and a very high concordance rate between the molecular status of BM and that of matched primary tumors.

MGMT promoter methylation status in brain metastases from colorectal cancer and corresponding primary tumors

BACKGROUND

Brain metastases (BM) from colorectal cancer are usually associated with poor prognosis. The aim of this retrospective study is to evaluate MGMT promoter methylation in BM and their corresponding primary colorectal cancer tumors.

MATERIALS & METHODS

MGMT promoter methylation status was assessed by pyrosequencing in 53 consecutive patients resected for BM. A concordance analysis between BM and matched primary tumor was performed in 39 cases.

RESULTS

MGMT methylation was found in 34 (64.2%) BM and in 25 corresponding primary tumors (64.1%). Median survival after neurosurgery was independent from MGMT promoter methylation (163 days for those with methylated MGMT versus 193 days for the unmethylated).

CONCLUSION

Epigenetic MGMT promoter methylation was common and the concordance between primary and secondary lesions was high.

Delayed Positivization of Cerebral Angiography in Reversible Cerebral Vasoconstriction Syndrome (RCVS) Presenting with Recurrent Subarachnoid Haemorrhage

Benign angiopathy of the central nervous system is a clinical syndrome with evidence of reversible cerebral vasoconstriction (RCVS). Haemorrhagic stroke, either subarachnoid or intracerebral is an unusual presentation of RCVS. We describe a case of RCVS presenting with a subarachnoid haemorrhage (SAH), with rebleeding and onset of hydrocephalus during the first week, and, notably, delayed evidence of typical angiographic features after two negative prior exams. Normalization of the angiographic vasculitic-like lesions was documented at month +6. Repeated cerebral angiograms are mandatory to exclude this kind of disease, and the uncommon presentation of this case reinforces this concept.

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.

Endoscopic third ventriculostomy in patients with secondary triventricular hydrocephalus from a haemorrhage or ischaemia in the posterior cranial fossa

BACKGROUND

The aim of this project was to evaluate the efficacy of endoscopic third ventriculostomy (ETV) in the treatment of acute hydrocephalus caused by a haemorrhage or ischaemia in the posterior cranial fossa.

METHODS

21 patients who had acute triventricular hydrocephalus resulting from ischaemia in 8 cases, and from cerebellar haemorrhage in 13 cases were treated with endoscopic third ventriculostomy. This series was compared with a control group of 30 patients, with clinical neuroradiological characteristics comparable to the preceding group (18 acute post-haemorrhage hydrocephalus and 12 post-ischaemia in the posterior cranial fossa), treated by external ventricular drainage (EVD). All patients were monitored clinically and by brain computed axial tomography (CT) to measure the dimensions of the lateral and third ventricles. The criteria used to define efficacy were based on the image of the postoperative cerebral CT scan.

RESULTS

No patient suffered haemorrhagic complications from surgical procedures or additional neurological deficits. There was no postoperative mortality or added morbidity. In all cases there was an improvement of intracranial hypertension. Clinical improvement was associated with a reduction of the ventricular dimensions documented by serial CT scans.

CONCLUSIONS

We consider that, in selected cases, ETV can be suggested as the first choice treatment instead of the classic EVD. In the overall management of such patients, ETV has no or a very low rate of complications and allows shorter hospitalisation and earlier transfer to rehabilitative structures.

Use of the arachnoid membrane of the cerebellopontine angle to transpose the superior cerebellar artery in microvascular decompression for trigeminal neuralgia: technical note

BACKGROUND

Microvascular decompression is an accepted, safe, and useful surgical technique for the treatment of trigeminal neuralgia. Autologous muscle or implant materials such as shredded Teflon are used to separate the vessel from the nerve but may occasionally be inadequate, become displaced or create adhesions and recurrent pain.

OBJECTIVE

The authors evaluated the use of arachnoid membrane of the cerebellopontine angle to maintain the transposition of vessels from the trigeminal nerve.

METHODS

The authors conducted a retrospective review of microvascular decompression operations in which the offending vessel was transposed and then retained by the arachnoid membrane of the cerebellopontine cistern, specifically by the lateral pontomesenchepalic membrane.

RESULTS

This technique was used in 30 patients of the most recently operated series. Postoperatively, complete pain relief was achieved in 90% of the patients without any observed surgical complications.

CONCLUSION

To the authors' knowledge this is the first report in which the arachnoid membrane is used in the microvascular decompression of the trigeminal nerve. While this technique can be used only for selected cases, the majority of the vascular compressions on the trigeminal nerve are due to the SCA, so this sling transposition technique can be useful and effective.

MULTISESSION CYBERKNIFE STEREOTACTIC RADIOSURGERY OF LARGE, BENIGN CRANIAL BASE TUMORS

OBJECTIVE

Although radiosurgery plays an important role in managing benign cranial base lesions, the potential for increased toxicity with single-session treatment of large tumors is a concern. In this retrospective study, we report the intermediate-term rate of local control, morbidity, and clinical outcomes of patients with large cranial base tumors treated with multisession stereotactic radiosurgery with the CyberKnife (Accuray, Inc., Sunnyvale, CA).

METHODS

Between 1999 and 2008, 34 consecutive patients with large (&gt;15 cm3), benign cranial base tumors (21 meningiomas, 9 schwannomas, 4 glomus jugulare tumors) underwent primary or postoperative radiosurgical treatment using a multisession approach at Stanford University and were considered in this retrospective study. Forty-four percent of these patients had undergone previous subtotal surgical resection or radiotherapy. CyberKnife radiosurgery was delivered in 2 to 5 sessions (median, 3 sessions) to a median tumor volume of 19.3 cm3 (range, 15.8–69.3 cm3). The median marginal dose was 24 Gy (range, 18–25 Gy) prescribed to a median 78% isodose line.

RESULTS

After a median clinical follow-up of 31 months (range, 12–77 months), 21% of patients experienced clinical improvement of neurological symptoms, whereas neurological status remained unchanged among the rest. Four patients experienced prolonged use of glucocorticoids owing to transient neurological worsening and radiographic signs of radiation injury. No permanent neurotoxicity was seen. To date, all tumors remain locally controlled.

CONCLUSION

Over our modest length of follow-up, multisession radiosurgery appears to be a safe and effective option for selected large, benign brain and cranial base lesions.

Headache attributed to intracranial tumours: A prospective cohort study

Between January 2007 and March 2008, we prospectively studied all patients operated on for intracranial tumours in our Department of Neurosurgery. Preoperatively, all patients were interviewed by a neurologist to collect headache characteristics. Measurements of tumour and oedema volume were made using dedicated software for magnetic resonance imaging studies. Tumour histopathology was established by histological examination postoperatively. If headache improved postoperatively, a diagnosis of ‘headache attributed to intracranial neoplasm’ was made, according to the 2004 International Classification of Headache Disorders (ICHD-II). A multivariate logistic regression model was used to evaluate the association of headache with potential risk factors. We studied 206 subjects. The prevalence of tumour headache was 47.6%. Intracranial tumour headache was non-specific and in most cases could not be classified by current ICHD-II diagnostic criteria for primary headache syndromes. Its prevalence varied depending on volume, location and type of tumour, as well as on the patient's previous headache history.

Neurosurgical management and postoperative whole-brain radiotherapy for colorectal cancer patients with symptomatic brain metastases

BACKGROUND

New systemic treatments for advanced colorectal cancer have conferred a survival advantage, allowing patients to reach a median survival of almost 2 years. Due to this remarkable life extension, the incidence of brain metastases, though still low, is progressively increasing over time. There is little reported data on the optimal strategy to manage brain lesions from colorectal cancer.

METHODS

To explore the role of an aggressive approach to colorectal cancer brain metastases, we retrospectively collected and analyzed data from 30 patients who underwent neurosurgical resection + whole-brain radiotherapy between March 1998 and December 2006. Univariate (logrank) and multivariate (Cox's model) analyses were used to identify prognostic factors.

RESULTS

Median age at the time of surgery was 66 years, median ECOG PS was 1, most patients (87%) had concomitant lung and/or liver metastases. Median number of previous chemotherapies was two, with half of the patients being exposed both to oxaliplatin and irinotecan. A median of 27 Gy of radiotherapy were administered to 16 patients after resection. At the time of the analysis, 29 out of 30 patients had died, with a median survival time after brain metastasectomy of 167 days (8-682). Only one patient died within a month from surgery. Median survival was significantly longer in patients who received postsurgical radiotherapy (7.6 vs. 4.7 months, P = 0.014).

CONCLUSIONS

Neurosurgical management of symptomatic brain metastases from colorectal cancer is feasible, relatively safe, and offers a chance of prolonged survival. Patients who received radiotherapy after resection experienced a better outcome.

Adult aqueductal stenosis presenting as a thunderclap headache: a case report

Thunderclap headache is well known to be a presenting feature of a variety of causal events. Indeed, a primary form is considered in the International Classification of Headache Disorders-II, but such diagnosis must be made only after exclusion of a possible secondary cause. We report a case of late-onset idiopathic aqueductal stenosis presenting with thunderclap headache, in the absence of abnormal neurological findings or indirect signs of raised intracranial pressure. The patient recovered completely after endoscopic third ventriculostomy. This case indicates primary aqueduct stenosis as a possible, never previously reported, cause of thunderclap headache.

Outcome of colorectal cancer (CRC) patients resected for brain metastases (BM)

14530

Background: Advances in systemic treatment for metastatic CRC confer survival advantage, allowing patients to reach a median survival of almost 2 years. As a consequence of this remarkable life extension, the incidence of BM from CRC, though still low, is increasing over time. The presence of BM is considered an index of poor prognosis, even when surgical resection is possible. Methods: To determine if an aggressive approach to BM from CRC could provide patients with clinical benefit or survival advantage, we retrospectively collected data from 29 CRC patients who underwent neurosurgical resection of BM between March 1998 and July 2006. Results: The median age at the time of surgical procedure was 65 years, median ECOG PS was 1, and the majority of patients (26 out of 29) had concomitant metastases at other sites. Lung and liver metastases were both common. Median number of previous chemotherapy regimens was two, with almost all of the patients being exposed both to oxaliplatinum and irinotecan-based regimens. After resection, 30 Gy of external whole-brain radiotherapy were administered to the majority of the patients. At the time of the analysis, 26 out of 29 patients had died, with a median survival time after brain metastasectomy of 210 days (8–682). Only 2 patients died within a month from surgery. We did observe prolonged survival for patients who received post-surgical radiotherapy (Kaplan Maier, p=0.033). Although death due to encephalic progression was reported for the patients with brain as the sole metastatic site, intracranial disease progression was not a clear predictor for poor survival in the whole cohort (p>0.05). Conclusions: Surgical resection of BM from CRC, whether followed by radiotherapy or not, is a feasible and safe technique, offering a chance of prolonged survival. Patients who received radiotherapy after complete neurosurgical resection have a better outcome.

No significant financial relationships to disclose.