Radiological and surgical aspects of polymorphous low-grade neuroepithelial tumor of the young (PLNTY).

BACKGROUND: Polymorphous low-grade neuroepithelial tumor of the young (PLNTY) is a low-grade epilepsy-associated tumor recently introduced in WHO 2021 classification. Since it has been recognized as an independent nosological entity, PLNTY has been mainly studied from a genetic and molecular perspective, not recognizing unique characteristic clinical and radiological features. METHODS: A systematic literature research has been conducted aiming to identify all relevant studies about the radiological, clinical and surgical features of PLNTY. We described a representative case of a 45-year-old man treated with awake-surgery with confirmed diagnosis of PLNTY, reporting the radiological and surgical characteristics through imaging and intra-operative video. We performed a statistical meta-analysis attempting to assess the presence of relationships between surgical and radiologic tumor characteristics and clinical outcome and type of surgery. RESULTS: A total of 16 studies were included in the systematic review. The final cohort was composed of 51 patients. Extent of resection (EOR) and outcome are not significantly associated with the different genetic profiling (p = 1), the presence of cystic intralesional component, calcification (p = 0.85), contrast-enhancing and lesion boundaries (p = 0.82). No significant correlation there is between EOR and remission or better control of epilepsy-related symptoms (p = 0.38). The contrast enhancement in the tumor is significantly associated with recurrence or poor control of epileptic symptoms (p = 0.07). CONCLUSIONS: In PLNTYs, contrast enhancement seems to impact prognosis, recurrence, and seizure control much more than radiological features, genetic features and type of resection of the tumor.

Cortical atrophy in chronic subdural hematoma from ultra-structures to physical properties.

Several theories have tried to elucidate the mechanisms behind the pathophysiology of chronic subdural hematoma (CSDH). However, this process is complex and remains mostly unknown. In this study we performed a retrospective randomised analysis comparing the cortical atrophy of 190 patients with unilateral CSDH, with 190 healthy controls. To evaluate the extent of cortical atrophy, CT scan images were utilised to develop an index that is the ratio of the maximum diameter sum of 3 cisterns divided by the maximum diameter of the skull at the temporal lobe level. Also, we reported, for the first time, the ultrastructural analyses of the CSDH using a combination of immunohistochemistry methods and transmission electron microscopy techniques. Internal validation was performed to confirm the assessment of the different degrees of cortical atrophy. Relative Cortical Atrophy Index (RCA index) refers to the sum of the maximum diameter of three cisterns (insular cistern, longitudinal cerebral fissure and cerebral sulci greatest) with the temporal bones' greatest internal distance. This index, strongly related to age in healthy controls, is positively correlated to the preoperative and post-operative maximum diameter of hematoma and the midline shift in CSDH patients. On the contrary, it negatively correlates to the Karnofsky Performance Status (KPS). The Area Under the Receiver Operating Characteristics (AUROC) showed that RCA index effectively differentiated cases from controls. Immunohistochemistry analysis showed that the newly formed CD-31 positive microvessels are higher in number than the CD34-positive microvessels in the CSDH inner membrane than in the outer membrane. Ultrastructural observations highlight the presence of a chronic inflammatory state mainly in the CSDH inner membrane. Integrating these results, we have obtained an etiopathogenetic model of CSDH. Cortical atrophy appears to be the triggering factor activating the cascade of transendothelial cellular filtration, inflammation, membrane formation and neovascularisation leading to the CSDH formation.

Development of a Novel Device for Decompressive Craniectomy: An Experimental and Cadaveric Study and Preliminary Clinical Application.

BACKGROUND: Decompressive craniectomy is an intervention of established efficacy in patients with intractable cerebral edema. OBJECTIVE: To evaluate a new device used in alternative to decompressive craniectomy. This device is designed to perform an augmentative craniotomy by keeping the bone flap elevated using specific cranial suspension titanium plates and giving the brain enough room to swell. METHODS: We tested the mechanical characteristics of the cranial brackets on dried skulls, on 3D-printed skull models, and on a preserved cadaver head. The resistance of the device was examined through dynamometric testing, and the feasibility of the surgical technique, including the suspension of the bone flap and the skin closure, was investigated on the cadaveric model. A preliminary clinical series of 2 patients is also reported. RESULTS: The laboratory tests have shown that this system allows an adequate expansion of the intracranial volume and it could withstand a force up to 637 ± 13 N in the synthetic model and up to 658 ± 9 N in the human skull without dislocation or failure of the brackets nor fractures of the bone ridges. Preliminary application in the clinical setting has shown that augmentative craniotomy is effective in the control of intracranial hypertension and could reduce the costs and complications associated with the classical decompressive craniectomy technique. CONCLUSION: Preliminary laboratory and clinical results show augmentative craniotomy to be a promising, alternative technique to decompressive craniectomy. Further clinical studies will be needed to validate its efficacy.

Vascular intracranial malformations and dementia: An under-estimated cause and clinical correlation. Clinical note.

Cerebrovascular malformations (CVMs) such as arteriovenous malformations (AVMs) or dural arteriovenous fistulas (DAVFs) represent a possible source of intracranial hemorrhage, but these malformations can also manifest with neurologic disorders secondary to ischemic penumbra from vascular steal. In the latter case, the clinical manifestations are less obvious and characteristic, and may include a varied clinical spectrum ranging from focal deficits to generalized malfunction of the brain parenchyma resulting in dementia. Dementias secondary to CVMs constitute a probably underestimated subpopulation of patients of great interest because they present with devastating but potentially reversible cognitive impairment. We examined the pertinent literature regarding the clinical manifestations of CVMs characterized by cognitive impairment and describe the distinctive clinical features. Our results confirm that cognitive impairment is one of the clinical manifestations of CVMs and is a frequently misrecognized and often late-diagnosed cause of reversible dementia.

Treatment of giant intracranial aneurysms: long-term outcomes in surgical versus endovascular management.

Aneurysms with a major diameter > 25 mm are defined as giant intracranial aneurysms (GIAs). Different clinical, pathological, and radiological factors were revealed as playing a role in choosing the best strategy between surgical and endovascular approaches. Despite the improvement of both techniques, the efficacy and safety of these different management are still debated. We evaluated the differences in clinical and radiological outcomes of GIAs treated with surgical and endovascular techniques in a large retrospective mono-centric study. We compared aneurysm location, clinical, morphological features, treatment outcome, and complications on the ground of treatment technique. The final cohort consisted of 162 patients. All the patients were assigned on the ground of the type of eligible treatment: surgical (118 patients) and endovascular procedure (44 patients). The different treatment strategies were made through a multidisciplinary selection whereas clinical parameters, location, and morphologic features of the aneurysm were considered. The surgical group manifested a greater reduction in performance levels and neurological status in the post-operative phases than the endovascular group (p < 0.01) with a higher incidence of complications (p = 0.012) in contrast to a lower recurrence rate (p > 0.01). There is no significant difference in post-operative mortality and survival between surgical and endovascular groups. The surgical group manifested a higher incidence of complications after treatment. The endovascular group has a better post-operative outcome, but a higher risk of recurrence and the necessity of further treatment.

Awake Surgery for Arteriovenous Malformations in Eloquent Areas Does Not Increase Intraoperative Risks and Allows for Shorter-Term Recovery and Improved Status.

BACKGROUND: Arteriovenous malformations (AVMs) located in eloquent areas are associated with a significant risk of neurologic deterioration. Awake surgery applied to intracranial AVMs could better identify eloquent areas, but its feasibility and application are controversial and limited to small case series. METHODS: We retrospectively reviewed a group of 59 brain AVMs located in eloquent areas surgically treated with asleep craniotomy and compared it with a combined group of patients treated with awake craniotomy. Patients were stratified into 2 groups: patients who underwent asleep surgery and patients who underwent awake surgery. With this study, we aimed to perform a complete analysis of surgical risks and outcomes for this subgroup of patients in order to provide a basis for a future prospective study. RESULTS: We compared the asleep group of 25 patients and the awake group of 34 patients. No statistically significant differences were identified regarding the risk of postoperative complications, surgical radicality, presence of residual, and need for adjuvant treatment (P = 1.00). The improvement in Karnofsky Performance Status (KPS) was more rapid and effective during follow-up in patients treated with awake surgery compared with asleep surgery (KPS at day 30 >70%-80% versus 87.2%, P = 0.01 and at 1year KPS >70%-80% vs. 96.9%, P = 0.02). CONCLUSIONS: In contrast to what is commonly believed, applying awake surgery to this lesion does not involve increased intraoperative risks. Still, it seems to determine a significant improvement in the outcome of patients from postoperative day 30 onwards.

Ameloblastoma and Intracranial Involvement: The Current Challenge of the Radical Surgical Treatment. Comprehensive Review of the Literature and Institution experience.

Background: Ameloblastoma (AMBL) is an odontogenic tumor, considered to be benign, but aggressive, whose principal risk is a recurrence. The growth can be enormous, and it can extend into the intracranial compartment with serious consequences. Purpose: The intracranial involvement of AMBL is rare, and it may require an extensive surgery. Although it is a rare condition for the neurosurgeon to treat, knowing this condition can lead to a significant increase in survival for these patients. Methods: A case of a 56-year-old woman presented with a history of recurrent left maxilla AMBL with intracranial extension and dural involvement of the anterior and medial cranial fossa is reported, followed by a systematic review of the literature with the aim to identify the best surgical treatment. Results: A total of 32 cases were included in the qualitative analysis. Management is varied and often not described, resulting in an almost complete lack of information and indications for treatment. Radical surgery tends to yield the best outcomes, and it is recommended to have adequate surgical margins when possible. Conclusions: Intracranial involvement from AMBL compartment is an uncommon manifestation of this rare pathology, but which deserves to be treated in a multidisciplinary way in order to ensure maximum surgical radicality. Recurrence reflects failure of the primary surgical resection. If recurrence is the major consideration, surgeons are encouraged to select radical surgery. Whenever a follicular-type maxillary AMBL is diagnosed, it is advisable to check for intracranial spreading and distant metastases during follow-up.

Sacral Nerves Reconstruction After Surgical Resection of a Large Sacral Chordoma Restores the Urinary and Sexual Function and the Anal Continence.

OBJECTIVE: Chordomas are slow-growing tumors, with a high tendency to local relapse. En bloc resection is related to the most favorable outcome in terms of survival but is frequently associated with permanent neurological deficits involving sphincters and sexual functions. In the present article, we describe an innovative technique of en bloc resection followed by reconstruction of the sacral nerves with nerve grafts. METHODS: The chordoma was excised through a posterior approach after dividing the proximal and distal sacral nerves using the established technique. After that, a microsurgical S2-S3-S4 nerve reconstruction was performed connecting the proximal and distal stumps with sural nerve grafts withdrawn from both lower limbs. RESULTS: Immediately after surgery, the patient experienced complete impairment of sexual function and sphincters with urinary and fecal incontinence. After 6 months, there was a progressive recovery of sexual function and sphincter control. One year after the operation, the patient achieved an adequate sexual life (erection and ejaculation) and complete control of the bladder and anal sphincter. CONCLUSION: Reconstruction of nerves sacrificed during sacral tumor removal has been shown to be effective in restoring sphincter and sexual function and is a promising technique that may significantly improve patients' quality of life.

Rapidly progressive dementia and Parkinsonism as the first symptoms of dural arteriovenous fistula. The Sapienza University experience and comprehensive literature review concerning the clinical course of 102 patients.

BACKGROUND: Dementia is a chronic loss of neurocognitive function that is progressive and irreversible. Dural arteriovenous fistulas (DAVFs) are acquired lesions that account for 10-15% of intracranial vascular malformations that could present with a rapid decline in neurocognitive function with or without Parkinson-like symptoms and evolve in a rapidly progressive dementia (RPD). Often the DAVFs are not even included in the differential hypotheses of this type of dementia and are not present in any type of diagnostic algorithm for evaluating RPD. METHODS: We performed a systematic review of the international literature and adding the cases coming from our institutional experience and we have collected all the reported cases of DAVFs that debut with ROD identifying the most frequent forms in terms of location and type, reporting the neurological characteristics and the outcome of each patient. RESULTS: The exact pathogenesis for developing dementia in patients with DAVFs remains largely unknown. The imaging changes and pathologic findings support the hypothesis that the clinical course results from the delivery of excessive volumes of blood flow into a venous system with outflow obstruction and venous congestion. The large variety of clinical manifestations of DAVFs depends on its location but this is not exactly valid for the onset of dementia. It supposed that the highly variable clinical manifestation of DAVFs has been convincingly related to the pattern of venous drainage more than location. CONCLUSIONS: Neurologists and clinicians generally are familiar with the differential diagnoses of slowly progressive neurodegenerative dementias, but the diagnosis of RPD entails a different diagnostic approach. Due to their curable nature, the diagnosis of DAVFs must be suspected when facing a RPD picture, even more so if it is associated with characteristic abnormalities of the hemispheric white matter.

Dorsal epidural "Spindle Cell Lipoma" in a pregnant female.

BACKGROUND: Spindle cell lipoma (SCL) constitutes just 1.5% of all lipomatous tumors. They typically occur in the upper back and shoulders. Here, we report a 37-year-old female presenting with a SCL in the dorsal epidural thoracic spine, during her 9th month of pregnancy. CASE DESCRIPTION: A 37-year-old female presented with a subacute (2 months) progressive paraparesis during her 9th month of pregnancy. The MR showed a dorsal epidural mass at the D8 level. Following a cesarean section, the patient underwent a laminectomy for tumor excision. Microscopically, the lesion proved to be a SCL. At 5-year follow-up, there was no tumor recurrence. CONCLUSION: SCL represents a variant of benign lipomas that may occur in the dorsal thoracic spine. Gross total excision may be followed by a benign clinical course without recurrence or malignant degeneration. Very atypical SCLs need closer follow-up to avoid the misdiagnosis of liposarcoma.

A rare case of Meckel's cave primary lymphoma: a case report and elaboration of the diagnostic algorithm.

Management of lesions involving Meckel's cave can represent a challenge for neurosurgeons, because of the deep-seated location and the surrounding complex neurovascular structures. Very small lesions arising from MC are generally asymptomatic and radiological follow-up with head MRI and PET-CT is sufficient to control these lesions. In rare cases, the rapid increase in the size of lesions and the alteration of the neurologic status make early histological characterization mandatory in the plethora of lesions arising from Meckel's cave; a very small percentage is represented by central nervous system lymphomas. Primary diffuse large B-cell lymphoma is the most commonly found. Aggressive surgery, in case of suspicious Meckel's cave lesions, is strongly discouraged, because this procedure may increase the risk of postoperative deficit and provides no survival benefit compared with biopsy alone. The aim of the present paper is to report a very rare case of primary Meckel's cave diffuse large B-cell lymphoma (only seven cases were described in literature) and standardize an operative algorithm to avoid the risks of an incorrect surgical conduct.

Far lateral lumbar disc herniation part 1: Imaging, neurophysiology and clinical features.

Far lateral lumbar disc herniations (FLLDH) represent a separate category of disc pathology which includes both intraforaminal and extraforaminal lumbar disc herniations, that are characterized by a peculiar clinical presentation, diagnostic and treatment modalities as compared to the more frequent median and paramedian disc hernias. Surgical treatment often represents the only effective weapon for the cure of this disease and over the years different approaches have been developed that can reach the region of the foramen or external to it, with different degrees of invasiveness. The diagnosis is more demanding and still underestimated as it requires a more detailed knowledge in the spine anatomy and dedicated radiological studies. Computerized tomography and in particular magnetic resonance imaging are the appropriate tools for the diagnosis of FLLDH. Despite the widespread use of these diagnostic tests, many cases of FLLDH are overlooked due to insufficiently detailed radiological examinations or due to the execution of exams not focused to the foraminal or the extraforaminal region. Neurophysiological studies represent a valid aid in the diagnostic classification of this pathology and in some cases they can facilitate the differential diagnosis with other types of radiculopathies. In the present study, a comprehensive review of the clinical presentation, epidemiology, radiological study and the neurophysiological aspects is presented.

Trigeminal Neuralgia Secondary to Intracranial Neoplastic Lesions: a Case Series and Comprehensive Review.

It is known that intracranial tumors may trigger trigeminal neuralgia (TN) in some patients although the exact prevalence and occurrence is not completely defined yet. In the present study, we present a case series of patients with brain tumor and a clinical diagnosis of TN as the first and main manifestation of the disease. A retrospective analysis was performed involving patients diagnosed with brain tumor whose exclusive clinical feature our department focused on was TN. In addition, a review of all published cases was performed. From January 2017 to November 2018, 718 patients with brain tumor were admitted to our department, 17 of which suffered of TN, of which 8 patients presented with at least another neurologic symptom and 9 patients presented with TN alone, with typical symptoms of stubbing electric pain in 6 cases. In our series, we found that 2.3% of patients admitted for brain tumors had TN. In 0.8% of cases, TN was the main clinical symptom. The prevalence of tumor lesion in patients with facial neuropathic pain is not defined, but it is a well-known recognized initial symptom; however, early cerebral magnetic resonance imaging (MRI) is not yet strongly recommended in patients with newly diagnosed trigeminal neuralgia. The purpose of this article is, especially in unusual cases, to show that the application of such MR techniques and preoperative evaluation may contribute to diagnosis, indication, and surgery planning.

Intracranial capillary hemangiomas: literature review in pediatric and adult population.

Capillary hemangiomas (CHs) of the central nervous system represent a rare diagnosed pathology. CHs are benign vascular tumors whose most common manifestations are dermal and mucous and mainly occur during childhood or adolescence, while the involvement of the central nervous system can occur in a wider age range. We conducted a PubMed research on literature published until March 2020. We only enrolled cases with histological documented presence of intracranial CH. For every case collected, we analyzed age, sex, localization, neuroimaging studies performed, the presence of extracranial CHs, symptoms, neurological deficits, extent of surgical resection (biopsy, partial or gross total), adjunct treatment received (radiotherapy, chemotherapy, Trans-Arterial Embolization TAE), and outcome. Up to March 2020, the literature review identified 52 cases to which we added the case of our personal experience. The mean age was 26 with slightly female prevalence (28 F, 25 M). The most common presenting symptom was headache (21 cases, 40%). The surgical treatment consisted of biopsy in 7 cases (13%), partial resection in 10 cases (19%), gross total resection in 31 cases (58.5%), biopsy followed by total resection in 2 cases (3%), and partial resection followed by total resection in 1 case (1.5%), and the diagnosis was obtained from an autopsy sample in 1 case (1.5%). For symptomatic lesions, surgery is a valid option to obtain histological characterization, neurological improvement, and where possible a total resection. Stereotactic radiotherapy can be used if the lesion is not surgically approachable or as an adjuvant treatment in case of partial resection, having shown good results in terms of long-term disease control.

Role of endoscopic surgical biopsy in diagnoses of intraventricular/periventricular tumors: review of literature including a monocentric case series.

The intra- and periventricular location tumor (IPVT) of a brain remains a hard challenge for the neurosurgeon because of the deep location and eloquent anatomic associations. Due to this high risk of iatrogenic injury, many surgeons elect to perform biopsies of such lesions to establish a diagnosis. On the one hand, stereotaxic needle biopsy (SNB) is a minimally invasive procedure but with a significant risk of complications and a high risk of lack of tissue for molecular analyses for this region [Fukushima in Neurosurgery 2:110-113 (1978)]; on the other hand, the use of endoscopic intraventricular biopsy (EIB) allows for diagnosis with minimal surgical intervention [Iwamoto et al. in Ann Neurol 64(suppl. 6):628-634 (2008)]. IPVTs and related CSF pathway obstructions can be safely and effectively treated with endoscopic techniques. It is not possible to compare EIB with diagnoses made by any other method or with the established treatment. We aim to analyze the accuracy of EIB results by comparing them with results of biopsies performed later, in other methods and thereby evaluating the treatment evolution considering our personal experience. The difficulties and complications encountered are presented and compared with those reported in the literature to obtain the best review possible for this topic. A systematic review of literature was done using MEDLINE, the NIH Library, PubMed, and Google Scholar yielded 1.951 cases for EIB and 1912 for SNB, according to standard systemic review techniques. Review was conducted on 50 studies describing surgical procedures for lesions intra- and para-ventricular. The primary outcome measure was a diagnostic success. We also consider 20 patients with IPVT treated in our department. Clinical characteristics and surgical outcome were evaluated and a systematic review of the literature was performed. Overall, all our biopsies were diagnostic, with a positive histologic sample in 100% of our patients. 8 patients underwent a concurrent endoscopic third ventriculostomy. 4 patients underwent a concurrent ventriculostomy combined with septostomy. For 1 patient was necessary the only septostomy combined with biopsy. Every case has obtained a histological diagnosis. The percentage of complications was very low with only 1 case of post-operative infection and 1 case of hemorrhage. It was impossible to create a specific comparison from literature data of IPVTs between a stereotactic and endoscopic procedure, it presents only the collection of pineal gland tumor [Kelly in Neurosurgery 25(02):185-194 (1989); Quick-Weller in World Neurosurgery 96:124-128 (2016)] or unknown location of the lesion in major review [Marenco-Hillembrand et al. in Front Oncol 8:558 (2018)]. The present study aims to report our experience with the surgical management of IPVTs. The EIB sample yields an accurate histologic diagnosis tumor, with a positive histologic sample in 87, 95% of patients. The choice of the appropriate procedure should consider not only the preference and the experience of the neurosurgeon but also the several other variables as the location. While some periventricular lesions are better approached by endoscopic techniques, others are more suited for stereotactic-guided approaches. The ability to perform an EIB and relieve tumor-associated hydrocephalus by neuroendoscopy is considered to be a benefit of this procedure since this is less invasive than other treatments.

Herpes Simplex Reactivation After Surgical Treatment of Trigeminal Neuralgia: A Retrospective Cohort Study.

BACKGROUND: Herpes simplex virus (HSV) reactivation after surgery for trigeminal neuralgia has long been recognized. Only a few studies to date have focused on this complication, and its actual incidence remains unknown. The aim of this study was to investigate the incidence of postoperative herpes labialis (HL) in a cohort of patients treated with either percutaneous balloon compression or microvascular decompression to identify potentially significant differences between different treatments. METHODS: A total of 92 patients who were operated on for TN with microvascular decompression (group A) or percutaneous balloon compression (group B) in the period 2010-2017 were retrospectively evaluated. The 2 subgroups of patients were compared according to history of previous HL and incidence of postoperative HL. RESULTS: The final cohort comprised 56 male and 36 female patients. Average age was 58.50 years; 30 male patients belonged to group A and 26 male patients belonged to group B. Lifetime incidence of episodes of HL before surgery in 18/58 patients in group A (31.0%) and 12/34 patients in group B (35.3%), with no statistically significant difference among subgroups. Postoperatively, 1/56 patients in group A (1.7%) experienced HL compared 5/34 patients in group B (14.7%), with a strongly statistically significant difference between the 2 subgroups. CONCLUSIONS: In our clinical experience, herpes simplex virus reactivation after surgery for trigeminal neuralgia is not so rare and is still not completely understood. Postoperative herpes simplex virus reactivation could be due to a direct mechanical injury on gasserian ganglion neurons, which is more common after percutaneous balloon compression.