Safety and diagnostic accuracy of neuroendoscopic biopsies: an international multicenter study

The Pediatric Epilepsy Surgery Interest Group (PESIG) under the auspice of the ISPN Research Committee: Availability of relevant technology and geographical distribution

PURPOSE

Epilepsy surgery for pediatric drug-resistant epilepsy has been shown to improve seizure control, enhance patient and family QoL, and reduce mortality. However, diagnostic tools and surgical capacity are less accessible worldwide. The International Society Pediatric Neurosurgery (ISPN) has established a Pediatric Epilepsy Surgery Interest Group (PESIG), aiming to enhance global collaboration in research and educational aspects. The goals of this manuscript are to introduce PESIG and analyze geographical differences of epilepsy surgery and technology availability.

METHODS

PESIG was established (2022) following an ISPN executive board decision. Using a standardized form, we surveyed the PESIG members, collecting and analyzing data regarding geographical distribution, and availability of various epilepsy treatment-related technologies.

RESULTS

Two hundred eighty-two members registered in PESIG from 70 countries, over 6 continents, were included. We categorized the countries by GDP as follows: low, lower-medium, upper-medium, and high income. The most commonly available technology was vagus nerve stimulation 68%. Stereoelectroencephalography was available for 58%. North America had statistically significant greater availability compared to other continents. Europe had greater availability compared to Africa, Asia, and South (Latin) America. Asia had greater availability compared to Africa. High-income countries had statistically significant greater availability compared to other income groups; there was no significant difference between the other income-level subgroups.

CONCLUSION

There is a clear discrepancy between countries and continents regarding access to epilepsy surgery technologies. This strengthens the need for collaboration between neurologists and neurosurgeons from around the world, to enhance medical education and training, as well as to increase technological availability.

Intraventricular Tumors: Surgical Considerations in Lateral and Third Ventricular Tumors

Management of lateral and third ventricular tumors has been a challenge for neurosurgeons. Advances in imaging and pathology have helped in a better understanding of the treatment options. Technical refinement of microsurgical technique and addition of endoscopy has enabled more radical excision of tumors, when indicated, and added more safety.A proper understanding of the pathology at various ages and treatment options is continuously evolving. Many pediatric tumors are amenable to conservative surgical methods with effective complementary treatments. However, radical surgery is required in many adults as the main treatment and for many benign tumors. Various intraventricular lesions encountered and their surgical management is reviewed here for their efficacy, safety, and outcome, encompassing changes in our practice over the last 20 years.

5-Aminolevulinic acid fluorescence-guided endoscopic surgery for deep-seated intraparenchymal tumors

AIM

The usefulness of 5-aminolevulinic acid (5-ALA) fluorescence-assisted surgery for maximum resection of malignant gliomas has been established. However, its usefulness when combined with endoscopic surgery for deep-seated tumors has not been well established. In this study, whether 5-ALA photodynamic diagnosis (PDD) is feasible and useful for endoscopic surgery was investigated.

METHODS

A specially designed endoscope for PDD that delivers white light or blue light (375-440 nm) as excitation light was used. The fluorescence emitted by the tumor was evaluated in the cavity during resection or at the tip of the sheath during biopsy. The intensity of fluorescence was classified into three categories: strong, vague, and negative.

RESULTS

A total of 30 intraparenchymal tumors were observed with a neuroendoscope and 5-ALA PDD; 16 patients underwent resection, and 14 underwent biopsy. Overall, 67% (20/30) of tumors showed positive fluorescence of protoporphyrin IX. High-grade gliomas (HGGs) including glioblastoma (GBM) and anaplastic astrocytoma (AA) showed strong fluorescence in 47% (7/15), vague fluorescence in 33% (5/15), and negative fluorescence in 20% (3/15) of cases. Low-grade gliomas (LGGs) showed vague fluorescence in 33% (1/3) and negative fluorescence in 67% (2/3). Diffuse large B-cell lymphoma (DLBCL) showed vague fluorescence in 38% (3/8) and negative fluorescence in 63% (5/8). Metastatic tumors showed strong fluorescence in 25% (1/4) and vague fluorescence in 75% (3/4). In the comparison of fluorescence evaluation, a significant difference was observed only in the comparison between HGGs and DLBCL (p = 0.049).

CONCLUSION

These results suggest that 5-ALA PDD-assisted endoscopic surgery is feasible and useful for deep-seated intraparenchymal tumors.

Neuroendoscopy: intraventricular and skull base tumor resection in children

During the last 30 years, the neurosurgeons have witnessed a revolution in the practice of interventricular surgery. The advent of neuroendoscopy at the end of the 1980s has allowed a minimally invasive management of a very large series of pathologies in pediatric neurosurgery ranging from hydrocephalus to arachnoid cyst to intraventricular tumors. The progresses in the management of hydrocephalus, intracranial cyst, and the fluid filled collection nevertheless has been more rapid and radical due to the simpler equipment that is necessary to perform this kind of surgery. The intraventricular tumors instead have been addressed in a slower way, and for many years, the only endoscopic procedure that was allowed on interventricular tumors was a biopsy associated with the management of hydrocephalus. Only very small tumors have been considered operable for complete removal during many years due to the limitations of the neuroendoscopic equipment and to the small calibers of the working channel. More recently, the advent of new devices and new surgical techniques are offering new perspectives on the possibility of intraventricular tumor surgery in children. In this review, we describe the historical perspective of the learning curve of intraventricular tumor surgery under neuroendoscopic control and try to offer a view of the future perspective in the removal of larger intraventricular tumors, analyzing the main indications for intraventricular endoscopic tumor surgery. We offer as well an historical perspective of the evolution of skull base surgery and endonasal transsphenoidal approach for skull-based tumors in children. This kind of surgery that has acquired widespread acceptance for many pathologies in adult age has diffused more slowly in pediatric neurosurgery due to the anatomical limitation observed in these age range. Also in this field, the slow evolution of the technique and of the technology available to neurosurgeons has allowed a very significant expansion of indication for the minimally invasive removal of skull base tumors in children.

Neuroendoscopy: history, endoscopes, and instrumentation

INTRODUCTION

Endoscopy was first employed in the surgical treatment of neurosurgical diseases early in the twentieth century, but did not become an established practice for a long time, mainly because of poor technology and clinical results. After a slow re-appearance in the 1980s, the 1990s saw an explosion of techniques and instrumentation. Continuing technological improvement has led to further expansion of surgical techniques and indications for use of neuroendoscopy.

DISCUSSION

The expansion of ventricular endoscopy has led to significant understanding of CSF disorders. Aqueduct stenosis as cause of hydrocephalus and arachnoid cysts are an example of pathologies, the concept and understanding of which now is considerably enhanced, due to the application of neuroendoscopy in their treatment. Management of loculated hydrocephalus has been facilitated considerably with the use of the endoscope. The concepts of aqueductoplasty, septostomy, and foraminoplasty of the foramina of Monro and Magendie emerged, which were previously unknown. Skull base surgery, especially surgery for craniopharyngioma, has seen dramatic improvement in results with the use of the endoscope. Coupling of the endoscope with neuronavigation has expanded technical capabilities even further. Overall, we can do a lot more with the endoscope now in comparison to 30 years ago.

CONCLUSION

We should always remember that the endoscope is only a tool. Its use has indications and limitations related to its design and our ability to extract the maximum, in the context of its shortcomings. Further technological advances will push surgical frontiers even more in years to come.

Neuroendoscopy in the management of pineal region tumours in children

INTRODUCTION

Pineal region tumours (PRTs) are more common in children and represent a wide variety of lesions. The practise of a radiation test dose is obsolete and a biochemical/histological diagnosis is recommended before further therapy. Many patients present with hydrocephalus. Advances in neuroendoscopic techniques have allowed safe and effective management of this obstructive hydrocephalus with an opportunity to sample cerebrospinal fluid (CSF) and obtain tissue for histopathology. Definitive surgery is required in less than a third. Endoscopic visualisation and assistance is increasingly used for radical resection, where indicated.

METHODOLOGY

Our experience of endoscopic surgery for paediatric PRTs from 2002 to 2021 is presented. All patients underwent MRI with contrast. Serum tumour markers were checked. If negative, endoscopic biopsy and endoscopic third ventriculostomy (ETV) were performed; and CSF collected for tumour markers and abnormal cells. For radical surgery, endoscope-assisted microsurgery procedures were performed to minimise retraction, visualise the extent of resection and confirm haemostasis.

RESULTS

M:F ratio was 2:1. The median age of presentation was 11 years. Raised ICP (88.88%) was the commonest mode of presentation. Nineteen patients had pineal tumours, one had a suprasellar and pineal tumour, one had disseminated disease, while six had tectal tumours. The ETB diagnosis rate was 95.45%, accuracy rate was 83.3% and ETV success rate was 86.96%.

CONCLUSION

Neuroendoscopy has revolutionised the management of paediatric PRTs. It is a safe and effective procedure with good diagnostic yield and allows successful concurrent CSF diversion, thereby avoiding major surgeries and shunt implantation. It is also helpful in radical resection of lesions, where indicated.

Evaluation of the Perioperative and Postoperative Course of Surgery for Pineal Germinoma in the SIOP CNS GCT 96 Trial

Background: CNS germinoma, being marker-negative, are mainly diagnosed by histological examination. These tumors predominantly appear in the suprasellar and/or pineal region. In contrast to the suprasellar region, where biopsy is the standard procedure in case of a suspected germ-cell tumor to avoid mutilation to the endocrine structures, pineal tumors are more accessible to primary resection. We evaluated the perioperative course of patients with pineal germinoma who were diagnosed by primary biopsy or resection in the SIOP CNS GCT 96 trial. Methods: Overall, 235 patients had germinoma, with pineal localization in 113. The relationship between initial symptoms, tumor size, and postoperative complications was analyzed. Results: Of 111 evaluable patients, initial symptoms were headache (n = 98), hydrocephalus (n = 93), double vision (n = 62), Parinaud syndrome (n = 57), and papilledema (n = 44). There was no significant relationship between tumor size and primary symptoms. A total of 57 patients underwent primary resection and 54 underwent biopsy. Postoperative complications were reported in 43.2% of patients after resection and in 11.4% after biopsy (p < 0.008). Biopsy was significantly more commonly performed on larger tumors (p= 0.002). Conclusions: These results support the practice of biopsy over resection for histological confirmation of pineal germinoma.

Combined Neuroendoscopic Techniques in the Management of Pediatric Brain and Skull Base Tumors: A Single-Institutional Case Series

BACKGROUND

Central nervous system tumors encompass the leading cause of cancer-related death in the pediatric population. Neuroendoscopic techniques have been optimized over the years, becoming an important tool for the management of brain tumors. Our study aims to review the indications for neuroendoscopic procedures and the feasibility of combined interventions.

METHODS

This is a single-center, self-adjudicated, retrospective experience. Inclusion criteria consisted of pediatric patients (≤18 years old) who underwent management of brain tumor or related diseases with the employment of neuroendoscopy.

RESULTS

A total of 47 patients undergoing 51 procedures met inclusion criteria. The mean age was 9.8 ± 4.6 years, and the majority were female (55.3%). Common indications for endoscopic intervention were hydrocephalus management (n = 24; 16 endoscopic third ventriculostomies and 9 septostomies), tumor biopsy (n = 19), cyst fenestration (n = 16), and tumor resection (n = 9). In one third of the cases, combined interventions occurred during a single operative session. Hydrocephalus was successfully managed in 74.4% of cases; tumor biopsy confirmed the diagnosis in 95.8% of cases, and gross total resection was achieved in 88.9% of cases. Cyst fenestration required reintervention in 3 cases: one case associated with initial cyst enlargement and 2 cases with the development of new tumor cysts separated from the originally fenestrated cyst. The overall complication rate was 6.3%, with only one major safety event, which was successfully managed.

CONCLUSIONS

Neuroendoscopy is an important minimally invasive tool for diagnosing and treating pediatric patients with brain tumors, permitting to address multiple problems in a single surgery.

Single-entry two-stage rotational outside-in technique for simultaneous ventriculostomy and pineal region biopsy using traditional ventricular endoscope: technical note and comparative review

BACKGROUND

Many methods are reported for simultaneous endoscopic 3^rd ventriculostomy and posterior 3^rd ventricular biopsy with their pros and cons. We describe a novel single-entry two-stage rotational outside-in technique using the common 6° ventriculoscope and contrast this with others.

TECHNIQUE

Using a single burr hole, at the line extended from aqueduct through the larger foramen of Monro in parasagittal imaging, the ventricular endoscope is first inserted with 6° angled view anteroinferior, the tip of endoscope sheath just beyond the anterior part of the foramen, and ventriculostomy performed using flexible catheter's beveled cut end and balloon in a curvilinear trajectory using peripheral visualization. Keeping camera in the same orientation, it is then rotated 180° having 6° angled view postero-inferior, endoscope sheath traversing the posterior part of the foramen close to the posterior 3rd ventricular target, and biopsy obtained with rigid forceps. This technique overcomes some of the limitations of other methods by exploiting the flexible catheters and the rotational advantage of the 6° angle of the traditional ventriculoscope.

CONCLUSION

Our single burr hole two-stage rotational technique for simultaneous third ventriculostomy and posterior third ventricular biopsy seems to be an excellent alternative to other methods which can be used with both traditional 6° and greater angled ventriculoscopes without any significant deterrent.

Non-invasive preoperative imaging differential diagnosis of pineal region tumor: A novel developed and validated multiparametric MRI-based clinicoradiomic model

BACKGROUND

Preoperative differential diagnosis of pineal region tumor can greatly assist clinical decision-making and avoid economic costs and complications caused by unnecessary radiotherapy or invasive procedures. The present study was performed to pre-operatively distinguish pineal region germinoma and pinealoblastoma using a clinicoradiomic model by incorporating radiomic and clinical features.

METHODS

134 pineal region tumor patients (germinoma, 69; pinealoblastoma, 65) with complete clinic-radiological and histopathological data from Tiantan hospital were retrospectively reviewed and randomly assigned to training and validation sets. Radiomic features were extracted from MR images, then the elastic net and recursive feature elimination algorithms were applied to select radiomic features for constructing a fusion radiomic model. Subsequently, multivariable logistic regression analysis was used to select the clinical features, and a clinicoradiomic model incorporating the fusion radiomic model and selected clinical features was constructed for individual predictions. The calibration, discriminating capacity, and clinical usefulness were also evaluated.

RESULTS

Seven significant radiomic features were selected to construct a fusion radiomic model that achieved an area under the curve (AUC) value of 0.920 and 0.880 in the training and validation sets, respectively. A clinicoradiomic model that incorporated the radiomic model and four selected clinical features was constructed and showed good discrimination and calibration, with an AUC of 0.950 in the training set and 0.940 in the validation set. The analysis of the decision curve showed that the radiomic model and clinicoradiomic model were clinically useful for patients with pineal region tumor.

CONCLUSIONS

Our clinicoradiomic model showed great performance and high sensitivity in the differential diagnosis of germinoma and pinealoblastoma, and could contribute to non-invasive development of individualized diagnosis and treatment of patients with pineal region tumor.

Management of severe intraoperative hemorrhage during intraventricular neuroendoscopic procedures: the dry field technique

OBJECTIVE

Neuroendoscopic procedures inside the ventricular system always bear the risk for an unexpected intraoperative hemorrhage with potentially devastating consequences. The authors present here their experience, and a stage-to-stage guide for the endoscopic management of intraoperative hemorrhages.

METHODS

A step-by-step guide for the management to gain control of and stop the bleeding is described including a grading system. More advanced techniques are presented in cases examples.

CONCLUSION

Most of intraoperative hemorrhages can be controlled by constant irrigation and coagulation. More advanced techniques can be applied quickly and easily to ensure control of the hemorrhages and avoid the need for a microsurgical conversion.

Outcome of endoscopic transcortical intraventricular biopsy of isolated thickened pituitary stalk lesions in children

OBJECTIVE

The purpose of this study was to investigate the efficacy and safety of endoscopic transcortical intraventricular biopsy in pediatric patients with isolated thickened pituitary stalk lesions.

METHODS

From 1994 to 2018, 16 pediatric patients (8 males and 8 females) underwent endoscopic transcortical intraventricular biopsy at a single institution to establish an accurate pathological diagnosis for appropriate treatment strategies.

RESULTS

Preoperatively, the median diameter of the pituitary stalks was 5.31 ± 1.67 mm (range 3.86-9.17 mm). Overall, the diagnostic yield at endoscopic intraventricular biopsy was 93.8%. Histopathological diagnosis included germinoma (n = 10, 62.5%), Langerhans cell histiocytosis (n = 4, 25%), pilocytic astrocytoma (n = 1, 6.3%), and pituicytoma (n = 1, 6.3%). Two patients developed new diabetes insipidus after the procedure, and 3 patients had new postoperative hypothyroidism. There were no postoperative neurological deficits in this series.

CONCLUSIONS

Neuroendoscopic biopsy via the transcortical intraventricular corridor was shown to be safe and to aid in a reliable histopathological diagnosis in the management of isolated pituitary stalk lesions in pediatric patients. It can be considered a minimally invasive alternative to open biopsy via transcranial or endonasal corridors.

Live Imaging of Primary Neurons in Long-Term Cryopreserved Human Nerve Tissue

Tissue cryopreservation provides a convenient solution for tackling one of the major problems in neuroscience research, namely, the scarce availability of human nerve tissues, especially if needed alive. While brain tissue can be used only postmortem, live nerve tissue can reasonably well be harvested from the periphery. A valuable source of primary neurons is the intestine, which compared with brain has the advantage to be safely accessible via endoscopy. The nerve tissue innervating the intestine (the enteric nervous system; ENS) can be sampled with regular endoscopic biopsy forceps and remains viable for multiple physiological and immunohistochemical tests, as previously demonstrated. Here, we present a method to preserve, over longer periods of time, human primary neurons contained in these biopsies. The use of a cryoprotective agent and the application of controlled cooling revealed to be crucial to properly store the nerve tissue and to enable functional measurements after thawing. These primary neurons were evaluated for functionality (live imaging) and morphology (histology) up to one year after cryopreservation. Calcium (Ca²⁺) imaging indicated that human primary neurons remained viable and responded to selective stimulations (serotonergic and nicotinic agonists) after cryopreservation. Additionally, immunohistochemistry performed with specific neuronal markers showed that nerve structure and neuronal morphology were retained, with no signs of cellular damage. In this study, we demonstrate that the human ENS is a realistic source of primary neurons, which can be successfully preserved over long times and as such can be exploited both for gastrointestinal-specific as well as for general neuroscience research.

Neuroendoscopy in the Surgical Management of Lateral and Third Ventricular Tumors: Looking Beyond Microneurosurgery

Background

Intraventricular tumors pose a surgical challenge because of the difficulty in reaching their deep location through safe corridors and their adherence or proximity to vital neurovascular structures. Although microneurosurgery is the mainstay of surgical management, neuroendoscopy aided by adjuncts, namely, navigation and ultrasonic aspirators, has made a great contribution to improving surgical results.

Objective

This article reviews the experience of a neurosurgical unit with endoscopic procedures for intraventricular tumors. The current indications, benefits, and complications of neuroendoscopy are described.

Materials and Methods

This is a retrospective, observational study of lateral and third ventricular tumors tackled either purely with an endoscope or with its assistance over 19 years in a single unit at Bombay Hospital Institute of Medical Sciences, Mumbai.

Results

Of a total of 247 operated patients with intraventricular tumors, 85 cases operated using an endoscope were included. The majority of the patients had a tumor in the third ventricle (n = 62), whereas 23 patients had tumor in the lateral ventricle. The most common pathologies were colloid cyst and arachnoid cyst (n = 18). An endoscope was used for microsurgical assisted excision of tumors in 31 cases, biopsy in 24, cyst fenestration in 23, and pure endoscopic excision in seven cases.

Conclusion

Microsurgery remains the gold standard for the removal of giant, vascular intraventricular tumors. However, endoscopic fenestration or excision of cysts and biopsy have become better alternatives in many cases. Endoscope-assisted microsurgery affords safety and helps in achieving a more complete excision.

Resection of intra- and paraventricular malignant brain tumors using fluorescein sodium-guided neuroendoscopic transtubular approach

BACKGROUND

The requirement of brain retraction and difficulty in distinguishing the tumor demarcation are challenging in conventional approaches to intra- and paraventricular malignant tumors (IV-PVMTs). Tubular retractors can minimize the retraction injury, and fluorescein-guided (FG) surgery may promote the resection of tumors. Our aim is to evaluate the feasibility, safety, and effectiveness of fluorescein-guided endoscopic transtubular surgery for the resection of IV-PVMTs.

METHODS

Twenty patients with IV-PVMTs underwent FG endoscopic transtubular tumor resection. Fluorescein sodium was administered before the dural opening. The intraoperative fluorescence staining was classified as "helpful" and "unhelpful" based on surgical observation. Extent of resection was assessed using postoperative magnetic resonance imaging. Karnofsky Performance Status (KPS) score was used to evaluate the general physical condition of patients.

RESULTS

There were 9 glioblastomas, 4 anaplastic astrocytomas and 7 metastatic tumors. "Helpful" fluorescence staining was observed in 16(80%) of 20 patients. Gross total resection was achieved in 16(80%) cases, near-total in 3(15%) cases, and subtotal in 1 (5%) case. No intra- or postoperative complications related to the fluorescein sodium occurred. The median preoperative KPS score was 83, and the median KPS score 3-month after surgery was 88.

CONCLUSION

FG endoscopic transtubular surgery is a feasible technique for the resection of IV-PVMTs. It may be a safe and effective option for patients with these tumors. Future prospective randomized studies with larger samples are needed to confirm these preliminary data.

Endoscopic needle biopsy of thalamic tumors: technical note

INTRODUCTION

Neuroendoscopic biopsy represents the procedure of choice for pure intraventricular lesions. Instead, in case of deep-seated paraventricular tumors, with intact ependyma, the advantage of neuroendoscopy over stereotactic biopsy is not so evident, because the lesion is not under direct vision; the tissue sample may be limited to more superficial ependymal layer, and bleeding may obscurate vision. Also, stereotactic biopsy may reserve additional problems for these lesions: inaccuracy caused by leak of cerebrospinal fluid and increased risk of severe hemorrhage due to damage of the ependymal vessels.

CASE REPORTS

We report two cases of young children affected by thalamic tumors that were biopsied using a modification of a recently proposed technique: endoscopic visual control, neuronavigated needle biopsy.

CONCLUSION

This technique may combine the accuracy of a stereotactic needle biopsy with the advantage of visual control on site of ependymal puncture and possibility of immediate bleeding control.

Endoscopic versus stereotactic biopsies of intracranial lesions involving the ventricles

Stereotactic biopsies of ventricular lesions may be less safe and less accurate than biopsies of superficial lesions. Accordingly, endoscopic biopsies have been increasingly used for these lesions. Except for pineal tumors, the literature lacks clear, reliable comparisons of these two methods. All 1581 adults undergoing brain tumor biopsy from 2007 to 2018 were retrospectively assessed. We selected 119 patients with intraventricular or paraventricular lesions considered suitable for both stereotactic and endoscopic biopsies. A total of 85 stereotactic and 38 endoscopic biopsies were performed. Extra procedures, including endoscopic third ventriculostomy and tumor cyst aspiration, were performed simultaneously in 5 stereotactic and 35 endoscopic cases. In 9 cases (5 stereotactic, 4 endoscopic), the biopsies were nondiagnostic (samples were nondiagnostic or the results differed from those obtained from the resected lesions). Three people died: 2 (1 stereotactic, 1 endoscopic) from delayed intraventricular bleeding and 1 (stereotactic) from brain edema. No permanent morbidity occurred. In 6 cases (all stereotactic), additional surgery was required for hydrocephalus within the first month postbiopsy. Rates of nondiagnostic biopsies, serious complications, and additional operations were not significantly different between groups. Mortality was higher after biopsy of lesions involving the ventricles, compared with intracranial lesions in any location (2.4% vs 0.3%, p = 0.016). Rates of nondiagnostic biopsies and complications were similar after endoscopic or stereotactic biopsies. Ventricular area biopsies were associated with higher mortality than biopsies in any brain area.

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.

Neurocognitive Complications after Ventricular Neuroendoscopy: A Systematic Review

In recent years, neuroendoscopic treatment of hydrocephalus and various ventricular pathologies has become increasingly popular. It is considered by many as the first-choice treatment for the majority of these cases. However, neurocognitive complications following ventricular neuroendoscopic procedures may occur leading mostly to amnesia, which might have a grave effect on the patient's quality of life. Studies assessing neurocognitive complications after ventricular neuroendoscopic procedures are sparse. Therefore, we conducted a systematic review assessing the available literature of neurocognitive complications and outcome after ventricular neuroendoscopy. Of 1216 articles screened, 46 were included in this systematic review. Transient and permanent neurocognitive complications in 2804 ventricular neuroendoscopic procedures occurred in 2.0% (n = 55) and 1.04% (n = 28) of the patients, respectively. Most complications described are memory impairment, followed by psychiatric symptoms (psychosyndrome), cognitive impairment not further specified, declined executive function, and confusion. However, only in 20% of the series describing neurocognitive complications or outcome (n = 40) was neurocognition assessed by a trained neuropsychologist in a systematic manner. While in most of these series only a part of the included patients underwent neuropsychological testing, neurocognitive assessment was seldom done pre- and postoperatively, long-term follow up was rare, and patient's cohorts were small. A paucity of studies analyzing neurocognitive complications and outcome, through systematic neuropsychological testing, and the correlation with intraoperative lesions of neuronal structures (e.g., fornix) exists in the literature. Therefore, the neurocognitive and emotional morbidity after ventricular neuroendoscopic procedures might be underestimated and warrants further research.

Fully Endoscopic Transforaminal-Transchoroidal Approach for Tectal Area Tumor Removal

BACKGROUND

The surgical approaches to lesions located in the tectal area have remained controversial. The essential functions in the surrounding areas and the difficulties in obtaining a good surgical view during tumor removal have made these procedures risky and challenging. Endoscopic transforaminal approaches have been previously described for biopsy and intraventricular tumor removal. However, the endoscopic transforaminal-transchoroidal gross resection technique for such cases has barely been described.

METHODS

The endoscopic entry points and trajectories were planned using preoperative magnetic resonance imaging. Once the endoscope was inside the ventricular system, the angles of work and tumor exposure of the upper posterior part of the third ventricle were carefully evaluated. If the angle of work was insufficient for tumor removal, the choroidal fissure was opened using endoscopic bipolar electrode and dissectors. Tumor removal was performed using an endoscopic ultrasonic aspirator. We have presented a 3-case series of patients affected by tectal tumors that were treated using a fully endoscopic transforaminal-transchoroidal approach.

RESULTS

Total gross resection of the tumors was achieved in 2 patients. Subtotal resection was achieved in the third patient. No major complications had developed in relationship to the procedure. No new cognitive impairment was reported secondary to this technique.

CONCLUSIONS

In our experience, a fully endoscopic transforaminal-transchoroidal approach was a suitable treatment for this complex pathological entity. Opening of the choroidal fissure added an extra angle of work and improved the exposure of the upper posterior part of the third ventricle.

Management of severe intraoperative hemorrhage during intraventricular neuroendoscopic procedures: the dry field technique

OBJECTIVE

The unexpected intraoperative intraventricular hemorrhage is a rare but feared and life-threatening complication in neuroendoscopic procedures because of loss of endoscopic vision. The authors present their experience with the so-called “dry field technique” (DFT) for the management of intraventricular hemorrhages during purely endoscopic procedures. This technique requires the aspiration of the entire intraventricular CSF to achieve clear visualization of the bleeding source.

METHODS

More than 500 neuroendoscopic intraventricular procedures were retrospectively analyzed over the last 24 years for documented severe hemorrhages, which were treated by the application of the DFT.

RESULTS

The technique was required in 6 cases, including tumor resection/biopsy, cyst resection, and intraventricular lavage. Additionally, the technique was applied as part of the planned strategy in 3 cases of endoscopic tumor removal. The hemorrhage was stopped in all cases and no associated postoperative deficits occurred.

CONCLUSIONS

Although severe hemorrhages are rare, the neurosurgeon needs to be aware of them and has to establish strategies for their management. Most hemorrhages can be stopped by constant irrigation and coagulation. In the other rare cases, the DFT is a safe, reliable technique and can be easily incorporated into endoscopic surgery.

Pineal region tumors: Long-term results of endoscopic third ventriculostomy and concurrent tumor biopsy with a single entry approach in a series of 64 cases

OBJECTIVES

Endoscopic third ventriculostomy and concurrent biopsy is increasingly used in management of the pineal region tumors. Our objective was to assess the results of single entry approach to surgically manage the tumors of the pineal region.

PATIENTS AND METHODS

A retrospective study was designed, and a series of 64 consecutive patients (31 male, 33 female) with pineal region tumor undergoing endoscopic third ventriculostomy and concurrent biopsy of the tumor was undertaken.

RESULTS

A total of 64 patients underwent simultaneous endoscopic third ventriculostomy and biopsy of the pineal tumors with a single entry approach. A positive initial diagnosis was established in 97% of patients. 5 patients (7%) required the insertion of an external ventricular drain which was removed in all patients after 72 h but in one case (1%) undergoing permanent VP shunt insertion. The postoperative complications were divided into two transient and permanent complications. The transient complications included intraventricular hemorrhage (18%), seizure (1 to two episodes of seizure) (5%), diabetes insipidus (3%) and meningitis (3%) all were successfully managed. The only permanent complication was memory deficits occurred in one patient (1%). There was no mortality rate in current study.

CONCLUSION

The results of this study support the safety and efficacy of endoscopic third ventriculostomy and concurrent biopsy of the pineal region tumors as a less invasive surgical method associated with low morbidity and mortality rate. Our data demonstrated how simultaneous endoscopic third ventriculostomy and biopsy of the pineal region tumors with a single entry approach can produce favorable results.

The diagnostic quality of needle brain biopsy specimens obtained with different sampling methods - Experimental study

The aim is to examine whether brain tissue samples obtained through needle biopsy are better for histopathological evaluation when obtained with defined vacuum pressure, a novel needle rotation method, and using different needle type - Laitinen or Nashold. Moreover the paper aims to answer the question: Does vacuum and mechanical injury resulting from different sampling methods damage the tissue specimen challenging the diagnosis?. Eight hundred biopsy specimens from fresh swine brains were obtained using Nashold and Laitinen brain biopsy needles through inner cannula cutting or needle rotation sampling at vacuum pressure, from 0 to 0.06 MPa. The specimen weight and tissue quality for microscopic assessment were evaluated using the Mair score. Rising aspiration pressure increased the biopsy sample weight. Needle rotation delivered larger biopsy samples than the standard method. Laitinen provided larger samples than the Nashold needle, with the same sampling method or vacuum pressure. A higher histopathological diagnostic quality of tissue was obtained with the Laitinen needle than with Nashold, with higher vacuum pressure than lower pressure and finally with needle rotation than the standard method. No tissue damage caused by higher suction pressure or method of tissue separation was documented. Brain tissue samples obtained through needle biopsy are better for histopathological evaluation when obtained with higher vacuum pressure, a novel needle rotation method and with Laitinen needle. Higher suction pressure and sampling methods did not cause tissue damage.

TROPHY registry study design: a prospective, international multicenter study for the surgical treatment of posthemorrhagic hydrocephalus in neonates

INTRODUCTION

Among children with hydrocephalus, neonates with intraventricular hemorrhage (IVH) and posthemorrhagic hydrocephalus (PH) are considered a group with one of the highest complication rates of treatment. Despite continued progress in neonatal care, a standardized and reliable guideline for surgical management is missing for this challenging condition. Thus, further research is warranted to compare common methods of surgical treatment. The introduction of neuroendoscopic lavage has precipitated the establishment of an international registry aimed at elaborating key elements of a standardized surgical treatment.

METHODS

The registry is designed as a multicenter, international, prospective data collection for neonates aged 41 weeks gestation, with an indication for surgical treatment for IVH with ventricular dilatation and progressive hydrocephalus. The following initial temporizing surgical interventions, each used as standard treatment at participating centers, will be compared: external ventricular drainage (EVD), ventricular access device (VAD), ventricular subgaleal shunt (VSGS), and neuroendoscopic lavage (NEL). Type of surgery, perioperative data including complications and mortality, subsequent shunt surgeries, ventricular size, and neurological outcome will be recorded at 6, 12, 36, and 60 months.

RESULTS

An online, password-protected website will be used to collect the prospective data in a synchronized manner. As a prospective registry, data collection will be ongoing, with no prespecified endpoint. A prespecified analysis will take place after a total of 100 patients in the NEL group have been entered. Analyses will be performed for safety (6 months), shunt dependency (12, 24 months), and neurological outcome (60 months).

CONCLUSION

The design and online platform of the TROPHY registry will enable the collection of prospective data on different surgical procedures for investigation of safety, efficacy, and neurodevelopmental outcome of neonates with IVH and hydrocephalus. The long-term goal is to provide valid data on NEL that is prospective, international, and multicenter. With the comparison of different surgical treatment modalities, we hope to develop better therapy guidelines for this complex neurosurgical condition.

Brain Tectal Tumors: A Flexible Approach

BACKGROUND AND IMPORTANCE

Mesencephalic tectal gliomas represent a subset of midbrain tumors, which are more frequent in children than in adults. They usually become symptomatic when causing hydrocephalus by occluding the aqueduct. Because of their slow progression, due to their benign histology, they are characterized by a relatively good prognosis, although hydrocephalus might jeopardize patients' prognosis. Treatment is usually represented by cerebrospinal fluid diversion associated or not with biopsy.

CLINICAL PRESENTATION

We report 2 illustrative cases of tectal gliomas in adults where endoscopic third ventriculostomy (ETV) and simultaneous endoscopic biopsy were obtained during the same operation by means of a single burr hole with a flexible endoscope.

CONCLUSION

We recommend using this overlooked neurosurgical tool for such cases, since it allows the surgeon to safely perform an ETV, then judge whether biopsy can be done or not, without harming the patient, and possibly achieving an important piece of information (histopathological diagnosis) to manage this subset of oncological patients.

Visual-Controlled Endoscopic Biopsy of Paraventricular Intraparenchymal Tumors

OBJECTIVE

Frame-based stereotaxy represents the gold standard for biopsy of deep-seated lesions. Visual control of possible bleeding in these lesions is not possible. Neuroendoscopic biopsy represents an alternative procedure for tissue sampling in deep-seated intraventricular lesions. The authors present a technique for transventricular-navigated endoscopic biopsy of lesions that are located in the paraventricular region.

METHODS

Biopsy of paraventricular pathologies was performed in 6 male and 6 female patients between March 2013 and September 2018. The patient age ranged from 18 to 82 years. All patients underwent a pure endoscopic procedure over a burr hole trepanation supported by frameless navigation of the sedan probe.

RESULTS

Histologic diagnoses were established in all biopsies. In all patients, a direct control of the biopsy area was feasible, and hemostasis could be obtained. In 5 patients, endoscopic third ventriculostomy was performed first due to obstructive hydrocephalus. In 1 patient suffering from obstructive hydrocephalus, a pellucidotomy was performed. In 9 cases, the initial postoperative course was uneventful. Three patients suffered from persistent hydrocephalus and had to be treated with ventriculoperitoneal shunt insertion.

CONCLUSIONS

Endoscopically conducted biopsies with the aid of navigated tracking of the probe represent a possible additional technique in selected paraventricular intraparenchymal pathologies. The endoscopic approach enables the direct visualization of the intraventricular surface and its vessels. In contrast to standard stereotactic biopsy, direct visual control of hemostasis can be obtained even in paraventricular tumors.

Tubular brain tumor biopsy improves diagnostic yield for subcortical lesions

PURPOSE

Molecular data has become an essential part of the updated World Health Organization (WHO) grading of central nervous system tumors. However, stereotactic needle biopsies provide only small volume specimens and limit the extent of histologic and molecular testing that can be performed. We assessed the use of a tubular retractor-based minimally invasive biopsy technique to provide improved tissue yield and diagnostic data compared to needle biopsy.

METHODS

Eighteen patients underwent an open transtubular biopsy compared to 146 stereotactic biopsies during the years of 2010-2018.

RESULTS

Tubular biopsies resulted in a higher volume of tissue provided to the pathologist than needle biopsies (1.26 cm³ vs. 0.3 cm³; p < 0.0001). There was a higher rate of non-diagnostic sample with stereotactic compared to transtubular biopsy (13% vs. 0%; p = 0.13). Six patients who underwent stereotactic biopsy required reoperation for diagnosis, while no transtubular biopsy patient required reoperation in order to obtain a diagnostic specimen. Postoperative hematoma was the most common post-operative complication in both groups.

CONCLUSIONS

Stereotactic transtubular biopsies are a viable alternative to stereotactic needle biopsies with excellent rates of diagnostic success and acceptable morbidity relative to the needle biopsy technique. As molecular data begins to increasingly drive treatment decisions, additional biopsy techniques that afford large tissue volumes may be necessary to adapt to the new needs of pathologists and treating oncologists.

Flexible Neuroendoscopic Diagnosis and Management of Ventricular Tumors: A Retrospective Cohort Study

BACKGROUND

Ventricular tumors (VTs) represent approximately 10% of intracranial lesions and are associated with hydrocephalus in 73.9%-100% of patients. We present our experience using flexible neuroendoscopy as a diagnostic and hydrocephalus-related treatment strategy for paraventricular and intraventricular tumors.

METHODS

This retrospective cohort included 27 pediatric and 21 adult patients with paraventricular or intraventricular tumors treated with flexible neuroendoscopy. Terminally ill patients and patients with incomplete data were excluded.

RESULTS

Male and female patients comprised 52% and 48% of the population, respectively. Mean patient age was 20.45 years (±18.65 SD). The most common tumor location was the thalamic and pineal region. Conclusive pathologic diagnosis was obtained in 40 patients (83.3%); the most common type of tumor was astrocytoma. Hydrocephalus was present in 38 (79.1%) patients, who were treated successfully with endoscopic procedures. There were no major complications.

CONCLUSIONS

Flexible neuroendoscopy is a strategic tool for diagnosis of VTs, especially in patients with associated hydrocephalus and VTs unreachable by other means. Flexible neuroendoscopy has a high rate of definitive diagnosis with low associated complications. More studies evaluating the long-term efficacy of flexible neuroendoscopy for hydrocephalus associated with VTs are needed.

Endoscopic biopsy of intra- and paraventricular brain tumors

Introduction

Selection of the optimal treatment method of intra- and paraventricular tumors often requires histopathological verification that can be obtained by endoscopic biopsy.

Aim

To discuss the usefulness of the method in their own experience.

Material and methods

The results of 32 biopsies carried out during a 15-year period were reviewed retrospectively. All tumors were located supratentorially, 25 of them were intraventricular and 7 paraventricular. In 18 patients the tumor was accompanied by internal hydrocephalus. If the ventricular system was narrow, the biopsy was supported by a neuronavigation system. A rigid neuroendoscope was used. The obtained material was subjected to intraoperative and final histopathological examination.

Results

Viable diagnostic material was obtained from all patients. In 11 patients with tumor of the posterior portion of the third ventricle, cerebrospinal fluid was collected additionally for diagnostic tests. In 9 patients with obstructive hydrocephalus concomitant third ventriculostomy was performed. In 4 patients with tumor of the interventricular foramen, the tumor mass was reduced and in 2 cases septostomy was performed. In 3 (9.4%) cases the histopathological diagnosis was descriptive and did not explain the nature of the lesion. Four biopsies resulted in persistent bleeding, in 3 patients transient memory impairments were observed, and in 1 patient an epileptic seizure occurred. Five patients needed ventriculoperitoneal shunt placement.

Conclusions

Endoscopic biopsy is a safe method to verify the histopathological nature of intra- and paraventricular lesions. It enables sampling of cerebrospinal fluid, reduction of tumor size, and in cases of coexisting obstructive hydrocephalus also third ventriculostomy or septostomy.

Pitfalls of Neuroendoscopic Biopsy of Intraventricular Germ Cell Tumors

OBJECTIVE

A neuroendoscopic biopsy has become common for the diagnosis of ventricular tumors. However, its utility in patients with germ cell tumors (GCTs) has not been well discussed. We examined the usefulness and pitfalls of neuroendoscopic biopsies of intraventricular GCTs at a single institution.

METHODS

We retrospectively studied 21 consecutive patients diagnosed with GCTs by a neuroendoscopic biopsy of the ventricular region via the lateral ventricle. We examined the localization of tumors, histologic diagnoses using biopsies, surgical complications, and consistency of the diagnosis at the latest follow-up.

RESULTS

Tumor specimens were obtained from a pineal lesion (n = 20), neurohypophysial lesion (n = 5), and lateral ventricular wall lesion (n = 2). In 5 patients, the specimens were obtained from multiple areas. The initial diagnoses were pure germinoma (n = 16), immature teratoma (n = 1), yolk sac tumor (n = 1), and mixed GCT (n = 3). Six of 21 patients needed a second transcranial removal of enhanced residual lesions in the course of the treatment. A discrepancy in the histologic diagnosis between 2 surgeries occurred in 3 patients: All 3 patients had a new diagnosis of teratoma component following transcranial surgery. No postoperative mortality or permanent morbidity related to the neuroendoscopic procedures was noted.

CONCLUSION

Neuroendoscopic biopsies are safe and useful for obtaining reliable histologic diagnoses in the management of GCTs. However, for GCTs with mixed histology, biopsies are susceptible to diagnostic errors, especially missing detecting a component of teratoma.

Augmented reality in intraventricular neuroendoscopy

BACKGROUND

Individual planning of the entry point and the use of navigation has become more relevant in intraventricular neuroendoscopy. Navigated neuroendoscopic solutions are continuously improving.

OBJECTIVE

We describe experimentally measured accuracy and our first experience with augmented reality-enhanced navigated neuroendoscopy for intraventricular pathologies.

PATIENTS AND METHODS

Augmented reality-enhanced navigated endoscopy was tested for accuracy in an experimental setting. Therefore, a 3D-printed head model with a right parietal lesion was scanned with a thin-sliced computer tomography. Segmentation of the tumor lesion was performed using Scopis NovaPlan navigation software. An optical reference matrix is used to register the neuroendoscope's geometry and its field of view. The pre-planned ROI and trajectory are superimposed in the endoscopic image. The accuracy of the superimposed contour fitting on endoscopically visualized lesion was acquired by measuring the deviation of both midpoints to one another. The technique was subsequently used in 29 cases with CSF circulation pathologies. Navigation planning included defining the entry points, regions of interests and trajectories, superimposed as augmented reality on the endoscopic video screen during intervention. Patients were evaluated for postoperative imaging, reoperations, and possible complications.

RESULTS

The experimental setup revealed a deviation of the ROI's midpoint from the real target by 1.2 ± 0.4 mm. The clinical study included 18 cyst fenestrations, ten biopsies, seven endoscopic third ventriculostomies, six stent placements, and two shunt implantations, being eventually combined in some patients. In cases of cyst fenestrations postoperatively, the cyst volume was significantly reduced in all patients by mean of 47%. In biopsies, the diagnostic yield was 100%. Reoperations during a follow-up period of 11.4 ± 10.2 months were necessary in two cases. Complications included one postoperative hygroma and one insufficient fenestration.

CONCLUSIONS

Augmented reality-navigated neuroendoscopy is accurate and feasible to use in clinical application. By integrating relevant planning information directly into the endoscope's field of view, safety and efficacy for intraventricular neuroendoscopic surgery may be improved.

Three-Dimensional, computer simulated navigation in endoscopic neurosurgery

BACKGROUND

In order to address the pre- and perioperative need for visualization and prediction of patient-specific anatomy for surgical planning, endoscopic neurosurgeons have increasingly relied on computerized navigation devices to guide their surgical approaches.

OBJECTIVE

This manuscript aims to review: 1) the use of neuronavigation in endoscopic neurosurgery for pre-operative planning, 2) the intraoperative advantages of neuronavigation in endoscopic neurosurgery, and 3) the effects of navigation guidance on operative time, registration accuracy, brain shift, and avoidance of complications. Limitations of the current neuroendoscopic navigation literature will be discussed.

METHODS

We conducted a search using PubMed-MEDLINE; the keywords "stereotactic navigation AND endoscopic surgery" and "simulation AND endoscopic neurosurgery". 36 studies were identified that addressed the use of neuronavigation in endoscopic neurosurgery. These studies were then further analyzed for topics relevant to computerized neuroendoscopy and reviewed for the purposes of this article.

CONCLUSION

Three-dimensional, frameless neuronavigation systems are useful in endoscopic neurosurgery to assist in the pre-operative planning of potential trajectories and to help localize the pathology of interest. Neuronavigation appears to be accurate to < 1-2 mm without issues related to brain shift. Further work is necessary in the investigation of the effect of neuronavigation on operative time, cost, and patient-centered outcomes.

Endoscopic Third Ventriculostomy: Outcome Analysis of an Anterior Entry Point

BACKGROUND

Endoscopic third ventriculostomy (ETV) is a safe and effective treatment for hydrocephalus. An entry point located 4 cm anterior to the coronal suture, 3 cm anterior to Kocher point, and approximately 9 cm from the pupil at the midpupillary line has been used successfully for the last 20 years in our center. We aimed to evaluate this alternative anterior entry point routinely used for ETV, with or without concurrent endoscopic biopsy.

METHODS

Patients undergoing this proposed entry point were examined to evaluate its safety and efficacy. Factors such as patients' age, sex, hydrocephalus etiology, tumor location and pathology, and complication rate were examined through regression analyses to evaluate their impact on tumor biopsy and ETV success rates, and the need for subsequent ventricular shunting.

RESULTS

A total of 131 patients were included in the study. ETV was successful in 125 (95.4%) patients. Of these, 26 (19.8%) patients required a biopsy, which was successful in 21 (80.8%) cases. A complication was observed in 10 (7.6%) patients, with a trend toward complications occurring after ETV failure. There was no association between ETV success rate and patients' age (P = 0.5) or sex (P = 0.99).

CONCLUSIONS

The anterior entry point is a safe and effective method for ETV, especially when considering concurrent ventricular tumor biopsy. This entry point may be considered as a more minimally invasive procedure when using rigid endoscopy and may also eliminate the need for a flexible scope.

A multiport MR-compatible neuroendoscope: spanning the gap between rigid and flexible scopes

OBJECTIVE Rigid endoscopes enable minimally invasive access to the ventricular system; however, the operative field is limited to the instrument tip, necessitating rotation of the entire instrument and causing consequent tissue compression while reaching around corners. Although flexible endoscopes offer tip steerability to address this limitation, they are more difficult to control and provide fewer and smaller working channels. A middle ground between these instruments-a rigid endoscope that possesses multiple instrument ports (for example, one at the tip and one on the side)-is proposed in this article, and a prototype device is evaluated in the context of a third ventricular colloid cyst resection combined with septostomy. METHODS A prototype neuroendoscope was designed and fabricated to include 2 optical ports, one located at the instrument tip and one located laterally. Each optical port includes its own complementary metal-oxide semiconductor (CMOS) chip camera, light-emitting diode (LED) illumination, and working channels. The tip port incorporates a clear silicone optical window that provides 2 additional features. First, for enhanced safety during tool insertion, instruments can be initially seen inside the window before they extend from the scope tip. Second, the compliant tip can be pressed against tissue to enable visualization even in a blood-filled field. These capabilities were tested in fresh porcine brains. The image quality of the multiport endoscope was evaluated using test targets positioned at clinically relevant distances from each imaging port, comparing it with those of clinical rigid and flexible neuroendoscopes. Human cadaver testing was used to demonstrate third ventricular colloid cyst phantom resection through the tip port and a septostomy performed through the lateral port. To extend its utility in the treatment of periventricular tumors using MR-guided laser therapy, the device was designed to be MR compatible. Its functionality and compatibility inside a 3-T clinical scanner were also tested in a brain from a freshly euthanized female pig. RESULTS Testing in porcine brains confirmed the multiport endoscope's ability to visualize tissue in a blood-filled field and to operate inside a 3-T MRI scanner. Cadaver testing confirmed the device's utility in operating through both of its ports and performing combined third ventricular colloid cyst resection and septostomy with an endoscope rotation of less than 5°. CONCLUSIONS The proposed design provides freedom in selecting both the number and orientation of imaging and instrument ports, which can be customized for each ventricular pathological entity. The lightweight, easily manipulated device can provide added steerability while reducing the potential for the serious brain distortion that happens with rigid endoscope navigation. This capability would be particularly valuable in treating hydrocephalus, both primary and secondary (due to tumors, cysts, and so forth). Magnetic resonance compatibility can aid in endoscope-assisted ventricular aqueductal plasty and stenting, the management of multiloculated complex hydrocephalus, and postinflammatory hydrocephalus in which scarring obscures the ventricular anatomy.

Neuroendoscopy via an Extremely Narrow Foramen of Monro: A Case Report

Herein, safe and reliable neuroendoscopic biopsy via an extremely narrow foramen of Monro (ENFM) for a non-hydrocephalic patient with hypothalamic and pineal region tumors was successfully applied. A 17-year-old boy presented with hypothalamic manifestations attributed to hypothalamic and pineal region tumors. Small ventricles were seen. Intraoperatively, to advance different diameter steerable fiberscopes via ENFM, the third ventricle was flushed to induce a moment increase in the intraventricular pressure with subsequent dilatation of FM. Postoperative course was uneventful. Histopathological studies revealed a yolk sac tumor. Adjuvant therapy was applied. Follow-up neuroimaging disclosed marvellous improvement of the condition. His symptoms gradually improved.

Endoscopic Histologic Mapping of a Mixed Germ Pineal Tumor

BACKGROUND

The accurate histologic diagnosis of germ cell tumors in the pineal region is a keystone for determining the best treatment strategy and prognosis. This situation poses a challenge for the neuropathologist, considering the lack of a standarized procedure to obtain biopsy samples, which results in few and small specimens, which are not suitable for diagnosis.

CASE DESCRIPTION

We report a case in which a pineal region mixed germ cell tumor was accurately diagnosed by performing histologic mapping through a dual burr-hole endoscopic approach. The technical pitfalls and other considerations necessary for obtaining an accurate diagnosis in this tumor subgroup are specified. In addition, the histologic analysis regarding the sampling technique used is described.

CONCLUSIONS

The supraorbital frontal endoscopic approach enables the surgeon to perform histologic mapping of pineal region tumors, allowing standarization of the procedure used to obtain the specimens. This approach could result in a more accurate diagnosis, especially in mixed germ cell neoplasms.

Endoscopic transventricular exploration with biopsy of the basal cisterns and the role of endoscopic third ventriculostomy in patients suffering with basal cistern meningitis and consecutive hydrocephalus

OBJECTIVES

The purpose of this work is to elucidate the efficacy of endoscopic basal cisterns exploration, biopsy, and third ventriculostomy (ETV) in patients with basal cistern meningitis and arachnoiditis.

MATERIALS AND METHODS

The cases and videos of all patients in whom flexible neuroendoscopy was performed during the period of January 2005-June 2012 at the University Hospital 'Dr. Ignacio Morones Prieto' in San Luis Potosí, México. A group of 47 patients with radiological diagnosis of basal meningitis, arachnoiditis, and negative cerebrospinal fluid analysis were included.

RESULTS

From the 28 (60%) patients with histological diagnosis, 22 (47%) were made from biopsy from the arachnoid membranes of the basal cisterns only, 4 (9%) only from the cerebral cortex, and 2 (4%) from both sites. There were no complications related to the endoscopic procedure. In 23 patients from the 42 with hydrocephalus, ETV was successful. The grade of diagnostic accuracy of both biopsies in detect etiology was 68% (28 of 47 patients), the diagnostic accuracy of arachnoid biopsy was 60%, and diagnostic accuracy of convexity brain biopsy was 21% with 24 and 6 patients, respectively.

DISCUSSION

Endoscopic transventricular biopsy of the basal cisterns seems to be a safe and a relatively accurate procedure. As longs as frozen subarachnoid space was not seen, the possibilities of performing ETV in hydrocephalus condition are elevated depending on the causal micro-organism.

Endoscopic Versus Stereotactic Procedure for Pineal Tumor Biopsies: Focus on Overall Efficacy Rate

OBJECTIVE

The management of pineal region tumors depends on the histologic subtypes. Two minimally invasive techniques are available: endoscopic intraventricular biopsies and stereotactic biopsies. The recent Southampton and Lille series are the largest endoscopic and stereotactic series of pineal region tumors reporting both diagnosis rate and accuracy rate, respectively; we elaborated on these results in the light of other recent studies.

METHODS

We compared the Southampton endoscopic series with the Lille series, reflecting our 25-year experience of stereotactic biopsies, and the metadata of the literature for both approaches, as reported in the 2013 Report of the French-Speaking Society of Neurosurgery on tumors of the pineal region.

RESULTS

The results of the Southampton series match the endoscopic literature, in particular regarding the diagnosis rate (81.2%) and the perioperative morbidity (25.0%), and provide a rarely reported accuracy rate (78.6%), giving access to the overall efficacy rate (63.8%). The results of the Lille series match the stereotactic literature and show better results than endoscopic biopsies concerning the diagnosis rate (98.9%), accuracy rate (100%), resulting overall efficacy rate (98.9%), and perioperative morbidity (6.4%).

CONCLUSIONS

The Southampton and Lille series provide a unique opportunity to compare the overall efficacy rates of endoscopic and stereotactic biopsies, respectively. The stereotactic approach is safer and more effective for biopsies of pineal region tumors. To improve the safety and reliability of endoscopic biopsies, various methods have to be evaluated: alternative burr-hole strategies, use of neuronavigation, and a combination of flexible and rigid endoscopes.

Resection of Intraventricular Tumors in Children by Purely Endoscopic Means

OBJECTIVE

Neuroendoscopy is increasingly being used in the management of intraventricular brain tumors. The role of endoscopy in diagnostic biopsy is well established. Expansion of these techniques may allow for definitive resection of intraventricular tumors. We report the feasibility and outcomes of endoscopic resection of select intraventricular tumors in children.

METHODS

The clinical characteristics of 11 children with solid intraventricular tumors who underwent tumor resection were reviewed. Twelve procedures were performed.

RESULTS

Gross-total resection was achieved in 11 of 12 cases (92%). Maximal tumor diameter ranged from 9 to 26 mm (mean, 16.6 mm). Pathologic results included subependymal giant cell astrocytomas, ependymomas, nongerminomatous germ cell tumors, and pilocytic astrocytomas. Mean follow-up was 35 months (range, 10-109 months). All patients returned to their neurologic baselines after surgery. Local tumor recurrence occurred in 1 patient and distant recurrence in another. In 1 patient, a transitory intraoperative increase of intracranial pressure without clinical implications occurred. There was no permanent morbidity or mortality in this series. Hydrocephalus was present preoperatively in 5 cases and was treated either with tumor removal alone or with an additional endoscopic third ventriculostomy. No patient required a ventriculoperitoneal shunt.

CONCLUSIONS

Neuroendoscopic gross-total resection of solid intraventricular tumors is a safe and efficacious procedure in carefully selected pediatric patients.

Strategies to improve the quality of survival for childhood brain tumour survivors

BACKGROUND

Tumours of the central nervous system (CNS) are the most frequent solid tumours and the second most frequent type of cancer in children and adolescents. Overall survival has continuously improved in Germany, since an increasing number of patients have been treated according to standardised, multicentre, multimodal treatment recommendations, trials of the German Paediatric Brain Tumour Consortium (HIT-Network) or the International Society of Paediatric Oncology-Europe (SIOP-E) during the last decades. Today, two out of three patients survive. At least 8000 long-term childhood brain tumour survivors (CBTS) are currently living in Germany. They face lifelong disease- and treatment-related late effects (LE) and associated socioeconomic problems more than many other childhood cancer survivors (CCS).

METHOD

We review the LE and resulting special needs of this particular group of CCS.

RESULTS

Despite their increasing relevance for future treatment optimisation, neither the diversity of chronic and cumulative LE nor their pertinent risk factors and subsequent impact on quality of survival have yet been comprehensively addressed for CBTS treated according to HIT- or SIOP-E-protocols. Evidence-based information to empower survivors and stakeholders, as well as medical expertise to manage their individual health care, psychosocial and educational/vocational needs must still be generated and established.

CONCLUSION

The establishment of a long-term research- and care network in Germany shall contribute to a European platform, that aims at optimising CBTSs' transition into adulthood as resilient individuals with high quality of survival including optimal levels of activity, participation and acceptance by society.

Comparison of Intracranial Neuroendoscopic Procedures in Children versus Adults

BACKGROUND

The emphasis regarding intracranial neuroendoscopy has been traditionally advocated and focused on the role in pediatric patients, although a significant usage has developed in adult patients. In this study, we examine and contrast the role of predominantly intracranial neuroendoscopy in both a pediatric and adult population with a minimum postprocedure follow-up of 5 years.

METHODS

A retrospective review was conducted for patients in the two hospitals that manage neurosurgical care for Southern Alberta, Canada, undergoing neuroendoscopic surgery between 1994 and 2008. The pediatric group was defined as age ≤17 years and the adult group as age ≥18 years.

RESULTS

A total of 273 patients who underwent a total of 330 procedures with a mean postprocedure follow-up of 12.9 years were identified. There were 161 adult and 112 pediatric patients, and both groups underwent surgery by the same surgeons. The most common procedure was endoscopic third ventriculostomy, accounting for 55% of procedures. One postoperative death occurred in an adult patient. Endoscopic third ventriculostomy success 1-year postprocedure was 81%, with only three late-term failures. Postoperative infection was the most common serious complication (two pediatric/four adult patients). Adult and pediatric patients had similar major complication rates (4.2% vs 5.7%, p=0.547).

CONCLUSIONS

Neuroendoscopy overall had a similar role in both pediatric and adult neurosurgical populations, with the most commonly associated complication being infection. Neuroendoscopy is an important therapeutic modality in the management of appropriate adult patients.