The minimally invasive transventricular endoscopic approach to third ventricular lesions in pediatric patients-all-rounder with limitations?

INTRODUCTION

The surgical management of third ventricular lesions poses unique challenges, requiring careful consideration of various approaches and techniques. This study focuses on the transventricular transforaminal endoscopic approach and aims to provide insights into its indications, limitations, technical nuances, and potential complications in pediatric patients.

METHODS

A retrospective analysis was conducted using data from a 13-year period on pediatric patients who were subjected to transforaminal endoscopic surgery for third ventricular lesions. The study utilized a prospectively maintained internal database, extracting demographic data, preoperative assessment, surgical details, and postoperative follow-up information. The surgical technique is presented in detail, and exemplary case reports highlight relevant surgical considerations.

RESULTS

Out of 578 endoscopic transforaminal procedures, 24 surgeries were performed on pediatric patients with third ventricular lesions. Performed procedures consisted of cyst resection (13 cases), solid tumor resection (4 cases), and tumor biopsies with CSF pathway restoration (7 cases). The mean age at the time of surgery was 7.6 years. Postoperatively, 14 patients showed transient nausea and vomiting (58.3%); 10 patients showed pneumocephalus on postoperative MRI (41.7%). No emergency postoperative re-interventions nor perioperative mortality were observed.

CONCLUSION

The endoscopic transventricular transforaminal approach is a safe approach for lesion resection, CSF pathway restoration, and tumor biopsy in pediatric patients with third ventricle lesions. The author's results support the use of this minimally invasive technique as an alternative to more extensive approaches, particularly to the interforniceal interhemispheric approach. However, surgical success is highly dependent to the individual surgeon's experience and moreover to a suitable indication setting. Careful preoperative planning and knowledge of the approaches' pro and cons is mandatory for successful application of this approach.

Full-endoscopic removal of third ventricular colloid cysts: technique, results, and limitations

Introduction

Colloid cysts (CCs) are rare benign lesions that usually arise from the roof of the third ventricle. They may present with obstructive hydrocephalus and cause sudden death. Treatment options include ventriculoperitoneal shunting, cyst aspiration, and cyst resection microscopically or endoscopically. This study aims to report and discuss the full-endoscopic technique for removing colloid cysts.

Materials and methods

A 25°-angled neuroendoscope with an internal working channel diameter of 3.1 mm and a length of 122 mm is used. The authors described the technique of resecting a colloid cyst by a full-endoscopic procedure and evaluated the surgical, clinical, and radiological results.

Results

Twenty-one consecutive patients underwent an operation with a transfrontal full-endoscopic approach. The swiveling technique (grasping the cyst wall and rotational movements) was used for CC resection. Of these patients, 11 were female, and ten were male (mean age, 41 years). The most frequent initial symptom was a headache. The mean cyst diameter was 13.9 mm. Thirteen patients had hydrocephalus at admission, and one needed shunting after cyst resection. Seventeen patients (81%) underwent total resection; 3 (14%), subtotal resection; and 1 (5%), partial resection. There was no mortality; one patient had permanent hemiplegia, and one had meningitis. The mean follow-up period was 14 months.

Conclusion

Even though microscopic resection of cysts has been widely used as a gold standard, successful endoscopic removal has been described recently with lower complication rates. Applying angled endoscopy with different techniques is essential for total resection. Our study is the first case series to show the outcomes of the swiveling technique with low recurrence and complication rates.

On Natural History and Management of Colloid Cysts: Time to Rethink?

BACKGROUND

Colloid cysts, although benign, may occasionally cause obstructive hydrocephalus and sudden death. Reliable prognostic factors for symptomatic progression have been sought, with heterogenous results.

METHODS

We conducted a retrospective review of all cases of colloid cysts of the third ventricle managed at our center between 2009 and 2019. Clinical and neuroimaging characteristics were analyzed using logistic regression in relation to symptomatic status and hydrocephalus. The cutoff values for outcome prediction were calculated using the receiver operating characteristic curve analysis.

RESULTS

There were 82 patients with colloid cysts, of whom 60 were asymptomatic and 22 symptomatic. None of the asymptomatic patients experienced acute neurologic decline or hydrocephalus during follow-up, whereas half (n = 11) of the symptomatic patients presented with hydrocephalus, 8 of whom had acute hydrocephalus. We found 3 putative candidate risk factors for symptomatic colloid cysts: T1-weighted magnetic resonance imaging hyperintense/mixed signal appearance (P = 0.004), location in risk zone I (P = 0.007), and a volume >236.49 mm3 (P = 0.007). Cyst diameter and volume/foramen of Monro diameter ratios had a decreasing trend over time among asymptomatic patients, providing new insights into the natural history of the disease.

CONCLUSIONS

Only a few asymptomatic colloid cysts showed progression requiring surgery, with no acute deterioration or fatal events, whereas the rest remained stable over time, thus supporting a more conservative approach for this group of patients. Higher risk for developing symptomatic colloid cyst was defined by a risk score that included T1-weighted magnetic resonance imaging appearance, risk zone, and colloid cyst volume, aiding the detection of patients at risk of clinical deterioration.

Practical, Stereotactic, Low-Profile Technique for Transcortical/Transventricular Colloid Cyst Removal Independent of Ventricular Size: Technical Note and Analysis of Approaches

BACKGROUND

In the presence of a dilated foramen of Monro, a transcortical, transforaminal approach is considered the safest and simplest approach for resection of colloid cysts. However, in the presence of small or normal frontal horns, numerous microsurgical approaches and, often complicated, variations have been described, invariably employing forms of stereotactic navigation.

OBJECTIVE

To report an alternative, accurate, microsurgical stereotactic low-profile technique.

METHODS

The small frontal horn is stereotactically targeted as previously described. Routine equipment is used to accurately create a novel, rigid, atraumatic surgical corridor.

RESULTS

After a 7-mm corticotomy, a peel-away catheter carrying the AxiEM stylet engages the target set as the frontal horn. All joints of the endoscope holder are locked, allowing only catheter advancement (y axis) while lateral (x axis) or anteroposterior (z axis) movements are secure. Two, 7-mm retractor blades are inserted. The extremely consistent anatomy of the foramen of Monro allows en bloc microsurgical removal without unnecessary coagulation of cyst wall or choroid plexus.

CONCLUSION

Despite a plethora of approaches to the rostral third ventricle, in the presence of normal or small frontal horns, including creation of transcallosal/interforniceal, suprachoroidal (or transchoroidal), and sub-choroidal, colloid cyst resection does not necessarily need to be convoluted. Technical nuances of an accurate, practical, minimally invasive technique are described.

Colloid Cyst: A Potentially Life-Threatening Etiology of Severe Headache in a Patient With Migraine

Headache is a common cause of emergency department (ED) visits. Migraine is a prevalent neurological disorder that is encountered by emergency physicians in day-to-day practice. However, patients with a known history of migraines should be carefully evaluated when presenting with headaches and serious pathologies of headache should be ruled out. We report the case of a 43-year-old woman, with a known history of classic migraine, who presented to the ED with a severe headache. She described the headache as persistent generalized pain. The headache was worse on awakening and bending. The headache did not improve with the use of oral sumatriptan. She reported that the current episode of headache is more severe than her usual migraine headaches. The patient underwent a cranial CT scan which demonstrated a homogenously hyperdense well-defined round lesion located in the midline at the approximate location of the foramen of Monro with prominent lateral ventricles, conferring the diagnosis of the colloid cyst. The patient underwent a right craniotomy with resection of the cyst using the transcallosal approach. Recognition of this important diagnosis is crucial to prevent serious neurological complications by having timely management.

Surgical approaches for resection of third ventricle colloid cysts: meta-analysis

Although outcome studies and systematic reviews have been published on the surgical treatment of third ventricle colloid cysts (TVCC), there are no meta-analyses that compare the outcomes for various surgical approaches. This meta-analysis assesses the outcomes and complications for transcortical, transcallosal, and endoscopic surgical approaches used to excise TVCCs. A meta-analysis of surgically excised TVCCs was performed with an assessment of outcome for transcortical, transcallosal, and endoscopic approaches. A random-effects model analyzed the extent of surgical excision. The analysis included reports that compared at least two of these surgical approaches, for a total of 11 studies comprising a population of 301 patients. The transcortical approach was associated with a higher incidence of complete excision compared to the endoscopic approach (OR = 0.137, p = 0.041), with no significant differences observed between transcortical and transcallosal approaches, and between transcallosal and endoscopic approaches. Comparison between endoscopic and pooled microsurgical approaches was also insignificant (OR = 0.22, p = 1). The risk of motor weakness was increased with the transcortical approach compared to the endoscopic approach (OR = 6.10, p = 0.018). There were no significant differences between transcortical and transcallosal approaches regarding newly onset seizures, and no significant mortality differences between all three approaches. This study demonstrates that microsurgical approaches are associated with a greater extent of resection compared to endoscopic approaches; however, best results are likely achieved based on the surgeon's expertise, flexibility, and case review.

Direct Inspection with Dual Endoscope Technique via Bilateral Transforaminal Approach Leading to Complete Resection of Recurrent Colloid Cyst of the Third Ventricle

BACKGROUND

Although endoscopic approaches are widely used for resection of colloid cysts because of the lower invasiveness, removal of the recurrent colloid cyst is still challenging. Total removal is sometimes difficult to achieve with single-port endoscopy because of the restricted access and working space. To compensate for these limitations, the dual endoscope technique via the bilateral transforaminal approach was chosen.

CASE DESCRIPTION

A 34-year-old woman with recurrent colloid cyst of the third ventricle was admitted to our department. She had a history of endoscopic subtotal removal at another institution. Reoperation was scheduled and the endoscopic bilateral transforaminal approach was chosen to ensure total removal with minimum complication risk. After decompression, the cyst was retracted toward the third ventricle floor via the right foramen of Monro. Under direct inspection with an angled scope via the right foramen of Monro, the cyst attachment on the third ventricle roof was sharply dissected via the left foramen of Monro, resulting in total removal.

CONCLUSIONS

The dual endoscope technique via the bilateral transforaminal approach can achieve better surgical outcome by obtaining direct visualization of the cyst attachment. Although the indication should be limited, this approach can be considered especially for patients with recurrent lesions involving possible adhesion to vital structures.