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Endoscopic management of pediatric brain tumors

Mark M. Souweidane


Primary endoscopic procedures for children with intraventricular brain tumors include endoscopic tumor biopsy and endoscopic tumor removal. The simultaneous treatment of hydrocephalus with endoscopic third ventricu-lostomy (ETV) or endoscopic septostomy increases the appeal of a minimally invasive endoscopic approach.


Eighty-five patients who underwent endoscopic management of an intraventricular brain tumor were identified from a prospective database. Of these patients, 26 were younger than 21 years of age at the time of diagnosis. The surgical technique, its success rate, and patient outcome were assessed. Illustrative cases are used in this study to detail the procedure of endoscopic tumor biopsy and resection.

Endoscopic tumor procedures were successful in 96% of cases (23 of 24 endoscopic tumor biopsy samples and both endoscopic tumor removals). Fourteen simultaneous procedures were performed to treat hydrocephalus successfully. There was no recognized morbidity from the surgical procedures.


Endoscopic surgery in children with intraventricular brain tumors is an effective and safe method for sampling of the lesion and, in select cases, its resection. This minimally invasive technique should be considered in situations in which the patient might thereby avoid a more conventional procedure, given the high rate of success and low morbidity associated with endoscopic management.

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Purely endoscopic resection of a choroid plexus papilloma of the third ventricle: case report

Maria M. Santos and Mark M. Souweidane

The authors report an illustrative case of a purely endoscopic surgical approach to successfully remove a solid choroid plexus papilloma of the third ventricle in an infant. A 10-week-old male infant first presented with transient episodes of forced downward gaze, divergent macrocephaly, a tense anterior fontanel, diastasis of the cranial sutures, and papilledema. Brain MRI revealed a small, multilobulated contrast-enhancing mass situated within the posterior third ventricle, with resultant obstructive hydrocephalus. A purely endoscopic removal of the tumor was performed through a single right frontal bur hole. Intraoperatively, a unique vascular tributary was recognized coming from the tela choroidea and was controlled with coagulation and sharp dissection. Postoperative MRI confirmed complete tumor removal, and the tumor was classified as a choroid plexus papilloma. There has been no evidence of tumor recurrence over 42 months of follow-up. With this case report the authors intended to show that endoscopic surgery can be an additional tool to consider when planning a choroid plexus tumor approach. It seems to be of particular interest in selected cases in which there are concerns about the patient's total blood volume, as in infants with potential hemorrhagic tumors and when it is possible to preoperatively identify a single vascular pedicle that can be approached early in the surgery.

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Endoscopic resection of colloid cyst in normal-sized ventricular system

Konstantinos Margetis and Mark M. Souweidane

Endoscopic resection of colloid cyst in patients with normal-sized ventricular system is challenging, because the limited intraventricular space increases the risk of injuring eloquent nervous structures and critical blood vessels. The utilization of frameless stereotaxy and tissue shaving device facilitates the procedure. An important operative step is the ventricular insufflation that allows for an endoscope introduction without causing inadvertent injury to the caudate nucleus. The attached clip shows the basic operative steps of the procedure. In this clip the solid colloid cyst contents necessitated an en-block colloid cyst resection, in lieu of initially aspirating the cyst contents and subsequently removing the cyst walls.

The video can be found here: .

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Anterior third ventriculostomy: an endoscopic variation on a theme

Mark M. Souweidane

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Neuroendoscopic resection of posterior third ventricular ependymoma

Case report

Neal Luther and Mark M. Souweidane

✓ The practice of neuroendoscopy in the definitive management of cystic tumors and hydrocephalus has been well established. Resection of solid intraventricular tumors by a primary endoscopic technique, however, has rarely been demonstrated. The authors present the case of a 31-year-old woman in whom endoscopic resection of a posterior third ventricular ependymoma was successfully accomplished. Metastatic workup yielded no sites of dissemination, adjuvant radiation therapy was deferred, and the patient has been without radiographic evidence of disease after 6 months of follow up. Endoscopic resection of solid tumors appears feasible in select patients and warrants further evaluation.

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Advances in the endoscopic management of suprasellar arachnoid cysts in children

Jeremy C. Wang, Linda Heier, and Mark M. Souweidane

Object. Suprasellar arachnoid cysts present unique management problems. The authors retrospectively reviewed six cases, in which endoscopic ventriculocystocisternotomy was performed, to identify specific neuroimaging features that aid both the accurate diagnosis of this entity and the postoperative assessment of fenestration patency.

Methods. Six consecutive children underwent treatment for suprasellar arachnoid cysts. Consistent radiographic features in all cases were identified. Through a single entry site, endoscopic fenestration was performed at both the apical and basal cyst membranes. Outcome was assessed using clinical examination, quantitative changes in cyst size, and triplanar magnetic resonance (MR) imaging with flow-sensitive (long TR) sequences.

In every case, the suprasellar cysts displayed three diagnostic MR imaging features: 1) vertical displacement of the optic chiasm/tracts; 2) upward deflection of the rostral mesencephalon and mammillary bodies; and 3) effacement of the ventral pons. Two patients initially underwent placement of a ventriculoperitoneal shunt before the cysts were recognized, but MR images obtained after shunt placement revealed the cysts. In a mean follow-up period of 26.2 months, all patients improved clinically. Postoperative imaging revealed a mean cyst volume decrease of 52.7% and a return to more normal suprasellar and prepontine anatomy. Flow-sensitive MR imaging confirmed pulsation artifact at all 12 fenestration sites. There was no surgery-related death and no additional cerebrospinal fluid diversion procedure was required.

Conclusions. To aid in the accurate diagnosis of prepontine arachnoid cysts, the authors identified several pathognomonic features on sagittal MR images: vertical deflection of the optic chiasm and mammillary bodies, as well as pontine effacement. Dual endoscopic fenestration into the intraventricular compartment and basal cistern is safe, and it effectively provides symptomatic relief by decreasing the cyst size. Triplanar flow-sensitive MR imaging sequences can confirm fenestration patency without the need for cine-mode MR imaging.

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Extruded contents of colloid cysts after endoscopic removal

Assem M. Abdel Latif and Mark M. Souweidane


Mineralized or desiccated colloid cysts pose some unique challenges to endoscopic removal. The extrusion of the solid matrix into the intraventricular compartment has not been previously reported and, as such, no guidance exists regarding its predilection, prevention, and fate.


Postoperative imaging studies in a registry of patients undergoing endoscopic removal of colloid cyst were reviewed to detect any solid matrix within the ventricular compartment. Preoperative images and operative notes were used to determine if any features were predictive. Serial postoperative images and clinical notes were used to characterize the implications of these findings.


From a review of 94 patients, 10 (10.6%) patients had evidence of an extruded intraventricular solid fragment (median follow-up 4 months; range 0.5–115 months). Of the evaluable patients, 7 of 9 patients had T1-weighted hyperintense and T2-weighted hypointense cysts on preoperative scans. Seventy-eight percent of the extrusions were on the same side as the endoscopic entry. Three patients demonstrated early fragment migration, but not after 8 months of radiological follow-up. All evaluable patients demonstrated improvement in their hydrocephalus, and none suffered a complication attributable to the intraventricular extruded fragments.


Intraventricular extruded colloid fragments can occur after endoscopic resection, with the possible risk demonstrated as cyst hypointensity on preoperative T2-weighted images. The finding does not seem to result in any clinical morbidity, and radiographic involution is the rule. Migratory capacity, however, does exist and justifies a more frequent imaging surveillance schedule and consideration for removal.

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The intersect of neurosurgery with diffuse intrinsic pontine glioma

JNSPG 75th Anniversary Invited Review Article

Claudia M. Kuzan-Fischer and Mark M. Souweidane

An invited article highlighting diffuse intrinsic pontine glioma (DIPG) to celebrate the 75th Anniversary of the Journal of Neurosurgery, a journal known to define surgical nuance and enterprise, is paradoxical since DIPG has long been relegated to surgical abandonment. More recently, however, the neurosurgeon is emerging as a critical stakeholder given our role in tissue sampling, collaborative scientific research, and therapeutic drug delivery. The foundation for this revival lies in an expanding reliance on tissue accession for understanding tumor biology, available funding to fuel research, and strides with interventional drug delivery.

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Cranial index of symmetry: an objective semiautomated measure of plagiocephaly

Technical note

Martin Zonenshayn, Eugene Kronberg, and Mark M. Souweidane

Object. The prevalence of deformational, or positional, plagiocephaly has increased during the last decade. Treatments vary among centers, ranging from expectant management to orthotic helmet therapy to craniofacial remodeling. This management variability is partially due to a lack of objective methods with which to measure the severity of plagiocephaly, as well as procedures that are not cumbersome or require radiographic studies. A simple and objective method of determining the degree of cranial deformation has been developed.

Methods. A headband placed around the head was marked with two adjustable points—one denoting the nasion and the other, the inion. A digital camera was used to image the head from a vertex view. The shape of the headband and the area of each hemisphere were then determined by analyzing the image on a personal computer in a semiautomated fashion. A cranial index of symmetry (CIS) was calculated and, by definition, equaled 100% for a perfectly symmetrical head. In this preliminary study, the authors studied eight children referred for evaluation of their plagiocephaly and eight infants referred for noncraniofacial entities.

In the unaffected infants the mean CIS was 96.3 ± 1.3% (± standard deviation). In children with clinical evidence of plagiocephaly, however, the CIS was 81.9 ± 3.4% (p < 0.001). Although the CIS in healthy children was never less than 95%, that in all infants with plagiocephaly was below 90%.

Conclusions. Although preliminary, this objective nonradiographic measurement of cranial symmetry appears to allow grading of the severity of positional plagiocephaly. The aforementioned methodology may potentially be used as an unbiased means of comparing different treatment modalities in longitudinal studies.

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Endoscopic management of intracranial cysts

Jeffrey P. Greenfield and Mark M. Souweidane


Endoscopic fenestration has been recognized as an accepted treatment choice for patients with symptomatic arachnoid cysts. The success of this procedure, however, is greatly influenced by individual cyst anatomy and location as well as the endoscopic technique used. This review was conducted to assess what variables influence the treatment success for different categories of arachnoid cysts.


Thirty-three consecutive patients who underwent endoscopic fenestration for treatment of an intracranial arachnoid cyst were identified from a prospective database. The surgical indications and techniques were reviewed, and surgical success rates and patient outcomes were assessed. Specific examples of each cyst category are included to illustrate the technical aspects of endoscopic cyst fenestration.

Endoscopic fenestration of arachnoid cysts was successful when judged by cyst decompression, and symptom resolution was noted in 32 (97%) of 33 cases. The one patient with short-term treatment failure underwent a successful repetition of the operation. There were no surgery-related morbidities or deaths.


Arachnoid cysts are a relatively benign pathological entity that can be managed by performing endoscopically guided cyst wall fenestrations into the ventricular system or cerebrospinal fluid–containing cisterns. Proper patient selection, preoperative planning of endoscope trajectory, use of frameless navigation, and advances in endoscope lens technology and light intensity combine to make this a safe procedure with excellent outcomes.