Endoscope-assisted removal of colloid cysts of the third ventricle

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.

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.

Feasibility and Challenges of Microsurgical Resection of Colloid Cysts in Patients with Preexisting Ventriculoperitoneal Shunts

BACKGROUND

Colloid cysts are the most common third ventricular tumor and may present with symptoms related to obstructive hydrocephalus. Although definitive endoscopic or microsurgical resection is the standard of care, patients may receive temporizing ventriculoperitoneal shunts when definitive management is deferred. Subsequent definitive treatment can be challenging because of the ventricular collapse and narrowing of the operative corridor. There is currently no literature evaluating the feasibility of definitive colloid cyst resection in patients with preexisting ventriculoperitoneal shunts.

METHODS

We retrospectively reviewed records for patients undergoing colloid cyst resection between 2009 and 2019 to identify patients with preexisting shunts prior to surgery.

RESULTS

Three patients had preexisting ventriculoperitoneal shunts. Two patients had been shunted at outside institutions where microsurgical or endoscopic resection was not available. One patient received a shunt from an outside surgeon when she was deemed a poor surgical candidate because of cardiac instability. All 3 patients underwent successful gross total colloid cyst resection via the transcallosal approach without recurrences during a mean follow-up of 4.2 years. All patients had intact cognitive and memory function and returned to work.

CONCLUSIONS

Surgical resection of colloid cysts is possible despite a preexisting ventriculoperitoneal shunt. Because the ventricular space may be collapsed postoperatively because of cerebrospinal fluid diversion, a transcortical route (either endoscopic or microscopic) can be complicated by a small operative corridor with reduced visibility. The transcallosal approach was safe and feasible in these cases for providing midline access with adequate visualization for complete resection despite ventricular collapse.

Endoscopic management of third ventricular colloid cysts in mildly dilated lateral ventricles

Colloid cysts of the third ventricle are considered as benign lesions. The clinical manifestations are not clear in most of cases. Many treatment options are available and endoscopic removal of the cysts proves to be a very successful method especially if the lateral ventricles are moderately or severely dilated. Sometimes, we faced cases with non- or mildly dilated ventricles which may add more risks to the operation, limit the radicality of removal, or abort the procedure entirely. Sixteen cases of colloid cyst with mildly dilated ventricles were operated upon between 2008 and 2016 using the rigid endoscopic system. Twelve were female and four were male. Their ages were between 17 and 40 years old. Headaches and epileptic fits were the presenting symptoms in 13 cases and 2 cases respectively. One case was asymptomatic. The patients were followed up from 1 to 4 years. Total removal in 12 cases and evacuation of the contents and partial removal in 4 cases. Mild transient complications occurred in the form of fever in seven cases, vomiting in four cases or short-term recent memory loss in three cases. No deaths occurred due to the procedures. Working endoscopically in enlarged ventricles is very effective and easy; however, small sized ventricles do not prevent safe and effective complete removal of colloid cysts. Cases with residual cyst wall do not suffer from recurrence.

Dry-field maneuver for controlling the massive intraventricular bleeding during neuroendoscopic procedures

PURPOSE

Massive hemorrhages pose a significant problem in intraventricular endoscopic surgeries. These hemorrhages have the potential to cause mortality and morbidity, particularly in excisional surgeries. Often, the bleeding can be controlled only by cauterization and liquid irrigation, due to the incongruity of the use of antihemorrhagic agents in the fluid. The final option to stop the massive bleeding is the dry-field maneuver. In this study, the effects and clinical results of the dry-field maneuver in bleeding control of a massive bleeding were investigated.

METHODS

Dry-field maneuver was retrospectively studied in a patient population that had massive bleeding during intraventricular endoscopic procedures.

RESULTS

Dry-field maneuver was used in seven patients. Four of these patients underwent some excisional surgery. The other two patients were operated for an endoscopic third ventriculostomy and one for intraventricular hemorrhage evacuation. It was observed that the hemorrhage in patients stopped rapidly after the dry-field maneuver. Moreover, there was no need for an antihemorrhagic material.

CONCLUSION

Dry-field maneuver is an option for providing hemostasis, particularly, for a massive hemorrhage. It also has the potential to be used in elective surgeries because it improves the visual quality.

Microsurgical Treatment of Colloid Cysts of the Third Ventricle

BACKGROUND

This study analyzes the results of surgical treatment in 377 patients with colloid cysts (CCs) of the third ventricle who were treated at the Burdenko Neurosurgery Institute from 1981 to 2015. Operations were performed by a single surgeon (the first author of the article).

METHODS

The transcallosal approach was used to remove CCs in 97% of cases. Total cyst removal was performed in 96% of cases (in 4% of cases, a small cyst capsule fragment was left on the veins and fornix); in 3 cases, the cyst recurred, which required its repeated removal.

RESULTS

Hydrocephalus symptoms regressed in 98% of patients. The most frequent complications in the early postoperative period were memory impairments of varying severity, with a tendency to regress by the time of discharge. Two patients had an intraventricular hematoma, which required operative exploration in 1 patient. There were 4 cases of meningitis (including 1 shunt-associated meningitis) and 5 cases of transient pyramidal insufficiency.

CONCLUSIONS

We made a preliminary assessment of the reasonability of the infratentorial supracerebellar approach for removal of CCs in 10 cases.

Influencing Factors Analysis of Facial Nerve Function after the Microsurgical Resection of Acoustic Neuroma

Objective

To explore and analyze the influencing factors of facial nerve function retainment after microsurgery resection of acoustic neurinoma.

Methods

Retrospective analysis of our hospital 105 acoustic neuroma cases from October, 2006 to January 2012, in the group all patients were treated with suboccipital sigmoid sinus approach to acoustic neuroma microsurgery resection. We adopted researching individual patient data, outpatient review and telephone followed up and the House-Brackmann grading system to evaluate and analyze the facial nerve function.

Results

Among 105 patients in this study group, complete surgical resection rate was 80.9% (85/105), subtotal resection rate was 14.3% (15/105), and partial resection rate 4.8% (5/105). The rate of facial nerve retainment on neuroanatomy was 95.3% (100/105) and the mortality rate was 2.1% (2/105). Facial nerve function when the patient is discharged from the hospital, also known as immediate facial nerve function which was graded in House-Brackmann: excellent facial nerve function (House-Brackmann I–II level) cases accounted for 75.2% (79/105), facial nerve function III–IV level cases accounted for 22.9% (24/105), and V–VI cases accounted for 1.9% (2/105). Patients were followed up for more than one year, with excellent facial nerve function retention rate (H-B I–II level) was 74.4% (58/78).

Conclusion

Acoustic neuroma patients after surgery, the long-term (≥1 year) facial nerve function excellent retaining rate was closely related with surgical proficiency, post-operative immediate facial nerve function, diameter of tumor and whether to use electrophysiological monitoring techniques; while there was no significant correlation with the patient’s age, surgical approach, whether to stripping the internal auditory canal, whether there was cystic degeneration, tumor recurrence, whether to merge with obstructive hydrocephalus and the length of the duration of symptoms.

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.

Combination of Neuroendoscopic and Stereotactic Procedures for Total Resection of Colloid Cysts with Favorable Neurological and Cognitive Outcomes

BACKGROUND

Despite a wide range of surgical procedures, an unresolved debate remains regarding which attempt is optimal for the treatment of colloid cysts in the third ventricle. In this article, we present a new combination of stereotactic and endoscopic techniques.

METHODS

This prospective study includes 27 consecutive patients with symptomatic primary and recurrent colloid cysts. All cysts were removed via a neuroendoscope through a rostral transfrontal, transforaminal approach. The endoscope was supported by an additional cannula fixed in the stereotactic frame. Both tools were inserted into one lateral ventricle through two separate burr holes using stereotactic guidance.

RESULTS

The median operating time was 135 minutes. All cysts were removed completely, and no mortality or permanent complications related to surgery occurred. The mean time of observation was 43.5 months (range, 3-78 months), and no clinical or radiologic recurrences were observed. One patient with a history of an infected ventriculoperitoneal shunt did not improve after cyst removal, but improved after subsequent reimplantation of the shunt. In all other cases, symptoms resolved (67%) or decreased (30%). Cognitive functions improved or remained unchanged in all 10 elective cases examined neuropsychologically before and after surgery.

CONCLUSIONS

The techniques we describe for removal of colloid cysts are safe and effective, even for recurrent cases, and they provide 100% total resection, favorable cognitive outcomes, low risk of recurrence, and low risk of morbidity. The disadvantages of this method are a longer time for surgery and the need for more complex instrumentation compared with conventional endoscopic resection.

Single port microsurgical technique for excision of third ventricular colloid cysts

INTRODUCTION

Colloid cysts are benign space-occupying lesions that account for 0.5-1.0% of brain tumors and arise from the velum interpositum or the choroid plexus of the third ventricle.

MATERIAL AND METHODS

We are describing a modified surgical technique that combines the positive attributes of being minimalistic, while retaining the effectiveness of microsurgery. In all 20 consecutive symptomatic patients with a preoperative magnetic resonance imaging (MRI) diagnosis of colloid cyst who came to the senior author between 2008 and 2011 were included in the study. The patient was kept supine with the head positioned neutrally in the sagittal plane and neck flexed at 20°. The tube of a 5 ml plastic syringe having an external diameter of 13 mm and an internal diameter of 12.6 mm was cut toward the nozzle end to the appropriate length depending upon the cortical thickness measured on the preoperative MRI.

RESULTS

The average operative time was around 90 min with maximum of 120 min. None of the patients had seizures preoperatively or postoperatively and in all cases antiepileptic medication could be stopped after 3-6 month of surgery. Two patients had short-term memory impairment which returned to near normal by 1-year following surgery.

CONCLUSION

A volume of 5 ml plastic syringe port technique decreases the operative morbidity and operative time. The wider corridor of working makes the simultaneously maneuverability of two surgical instruments feasible enhancing safety and completeness of excision.

Ventricular endoscopy in the pediatric population: review of indications

INTRODUCTION

Neuroendoscopy has greatly impacted pediatric neurosurgery over the past few decades. Improved optics and microsurgical tools have allowed neuroendoscopes to be used for a multitude of neurosurgical procedures.

DISCUSSION

In this review article, we present the breadth of intraventricular neuroendoscopic procedures for the treatment of conditions ranging from hydrocephalus and brain tumors to congenital cysts and other pathologies. We critically discuss treatment indications and reported success rates for neuroendoscopic procedures. We also present novel approaches, technical nuances, and variations from recently published literature and as practiced in the authors' institution.

The Significance of Cyst Remnants After Endoscopic Colloid Cyst Resection

BACKGROUND:

Controversy surrounds the fate of cyst remnants after endoscopic colloid cyst resection.

OBJECTIVE:

Our study evaluated recurrence rates in patients with total endoscopic resection of colloid cysts vs those with coagulated cyst remnants.

METHODS:

Sixty-five consecutive patients and 67 procedures for endoscopic resection of colloid cysts from 1995 to 2011 were reviewed. Degree of resection was based on intraoperative assessment and postoperative magnetic resonance imaging (MRI). Recurrence rates were compared between patients with complete resection those with coagulated cyst remnants.

RESULTS:

Data analysis was performed of 56 patients and 58 procedures, with no follow-up in 9 patients. All patients had MRI-defined complete resection. On intraoperative assessment, 9 procedures had coagulated remnants and 45 procedures had complete resection (4 data unknown). The overall recurrence rate was 6.89% (4/58), 33.3% (3/9) with cyst remnants, and 2.2% (1/45) with total resection (P = .0124). Maximum follow-up was 144 months (mean, 40.4 months). Mean follow-up was 66.0 months for cyst remnant cases, and 33.5 months for totally resected cases. There was no mortality or permanent morbidity. Transient morbidity included memory deficit (n = 2), aseptic meningitis (n = 1), and local wound infection (n = 1).

CONCLUSION:

Endoscopic colloid cyst resection results in a low overall recurrence rate. Immediate postoperative MRI was insufficient for assessing degree of resection and was a poor predictor of recurrence. Ablation of cyst remnants rather than total removal is associated with a significantly higher rate of recurrence. The primary goal of endoscopic surgery should, therefore, be removal of all cyst contents and wall remnants.

Real time parallel intraoperative integration of endoscopic, microscopic, and navigation images: a proof of concept based on laboratory dissections

Endoscope, microscope, and neuronavigation systems are integrated in neurosurgical procedures mainly by using a serial combination algorithm, where, the user must switch his/her field of view from one platform display to another. The integration of theses devices could be optimized by incorporating different displays into one viewing platform thus achieving a parallel combination. In this study, we investigated the feasibility and the applicability of parallel integration of microscopic, endoscopic, and neuronavigation images by real time displaying the endoscope and neuronavigation image datasets in the main operative microscope oculars. The proposed set-up was effective in displaying the three images dataset in an operationally actionable mode. Ergonomically, the ability of using the different image dataset without the need of taking the eyes off the microscope oculars did not disrupt the flow or the tempo of the operative procedure. However, new endoscopes specific to this application are recommended.

Endoscopic technique in the treatment of patients with colloid cysts of the third ventricle. Report based on over a decade of experience

BACKGROUND AND PURPOSE

The aim of the work was a retrospective analysis of the efficiency of endoscopic treatment of patients with colloid cysts of the third ventricle.

MATERIAL AND METHODS

The analysis covered 17 patients. There were 19 operations in total. The follow-up period ranged from 21 to 130 months. The effectiveness of the method was evaluated by comparing neurological condition and magnetic resonance imaging (MRI) before and after treatment.

RESULTS

The mean duration of surgery was 81 minutes. The cyst was removed completely in 8 patients, subtotally in 5, partially in 3, and in 1 case a biopsy was performed. No persistent intra- or postoperative complications or deaths occurred. Immediately after the operation symptoms withdrew completely in 8 patients and partially in 9. In the long term follow-up period, all symptoms receded completely in 11 patients and a further 6 patients showed partial improvement. MRI revealed the absence of the cyst in 8 patients, in 2 patients the tumor was smaller in size and in a further 7 patients some small parts of the walls of the cyst were present. The width of the ventricle system returned to its normal size in 8 patients, decreased in 8 patients and in 1 case remained at its initial size. In 2 patients temporary postoperative complications occurred. The average hospitalization time was 9 days.

CONCLUSIONS

Recurrences of colloidal cysts after subtotal and partial removal do not occur very often, and the time of the recurrence may either be very long or it may not happen at all. Although we recommend complete removal of the cyst, this should not be pursued at the cost of incurring operative complications.

Singapore's anatomical future: quo vadis?

The disciplines of anatomy and surgery are not dichotomous since one is dependent on the other. Traditionally, surgeons predominantly taught gross and clinical anatomy. In this review, we examine the context of how human anatomy is taught nowadays. In essence, we discovered that there are certain discernable trends consistently observable between the American and British systems. In Singapore, the British Russell Group first influenced its education landscape but now more so by the American Ivy League. Singapore now has three medical schools all offering differing anatomy curricula, which serves as an opportune time for it to consider if there is a best approach given that the practice of surgery is also evolving in parallel. This review discusses the various pedagogies and issues involved, and will serve as a forum and stimulus for discussion. By tweaking the curriculum correctly and the lessons learnt, future doctors and surgeons in training will receive a better anatomical education, not just in Singapore but the world in general. Key recommendations include the use of body painting, clay, plasticine to facilitate the learning of anatomy, and the implementation of a body donation program. Furthermore, strategic mergers with key stakeholders will also ensure the survival of the discipline.

Rate of recurrence following stereotactic aspiration of colloid cysts of the third ventricle

BACKGROUND

The rate of recurrence following stereotactic aspiration of colloid cysts is not defined in the literature.

AIMS

To study the long-term imaging and clinical outcome in patients who had stereotactic aspiration of colloid cysts of the third ventricle.

METHODS

Between 1987 and 1994, computerized tomography-guided stereotactic aspiration was attempted in 26 consecutive patients with colloid cysts of the third ventricle.

RESULTS

There was no mortality or permanent morbidity. A complete aspiration of the cyst was possible in 17 patients, a partial aspiration of the cyst was achieved in 6 and the aspiration failed in 3 patients. On long-term follow-up, symptomatic recurrence was noted in 5/6 patients after partial aspiration and 4/17 patients after complete aspiration (mean follow-up 84.8 months). Kaplan-Meier analysis revealed that after complete aspiration of the cyst, median time to recurrence on imaging is 42 months (95% CI 23.0-60.9 months) but median time to symptomatic recurrence is much later at 184 months (95% CI 88.2-279.7 months).

CONCLUSIONS

Stereotactic aspiration of colloid cysts remains a valid surgical option as complete aspiration leads to a good long-term outcome in several patients. Partial aspiration of the cyst should be followed by excision of the cyst, due to the high rate of symptomatic recurrence. However, periodic follow-up imaging is mandatory even after complete aspiration as delayed recurrences are possible.

Supracerebellar infratentorial endoscopically controlled resection of pineal lesions: case series and operative technique

OBJECT

The heterogeneous clinical manifestations and operative characteristics of pathological entities in the pineal region represent a significant challenge in terms of patient selection and surgical approach. Traditional surgical options have included endoscopic transventricular resection; open supratentorial microsurgical approaches through the midline, choroidal fissure, lateral ventricle, and tentorium; and supracerebellar infratentorial (SCIT) approaches through the posterior fossa. The object of the current study was to review the preoperative characteristics and outcomes for a cohort of patients treated purely via the novel endoscopically controlled SCIT approach.

METHODS

A single-institution series of 9 consecutive patients (4 male and 5 female patients [10 total cases]; mean age 21 years, range 6-37 years) treated via the endoscopically controlled SCIT approach for a pathological entity in the pineal region was retrospectively reviewed. The mean follow-up time was 13.2 months.

RESULTS

The endoscopically controlled SCIT approach was successfully used to approach a variety of pineal lesions, including pineal cysts (6 patients), epidermoid tumor, WHO Grade II astrocytoma (initial biopsy and recurrence), and malignant mixed germ cell tumor (1 patient each). Gross-total resection and/or adequate cyst fenestration was achieved in 8 cases. Biopsy with conservative debulking was performed for the single case of low-grade astrocytoma and again at the time of recurrence. The mean preoperative tumor and cyst volumes were 9.9 ± 4.4 and 3.7 ± 3.2 cm(3), respectively. The mean operating times were 212 ± 71 minutes for tumor cases and 177 ± 72 minutes for cysts. Estimated blood loss was less than 150 ml for all cases. A single case (pineal cyst) was converted to an open microsurgical approach to enhance visualization. There were no operative complications, as well as no documented CSF leaks, additional CSF diversion procedures, or air emboli. Seven patients underwent concomitant third ventriculostomy into the quadrigeminal cistern. At the time of the last follow-up evaluation, all patients had a stable or improved modified Rankin Scale score.

CONCLUSIONS

The endoscopically controlled SCIT approach may be used for the biopsy and resection of appropriately selected solid tumors of the pineal region, in addition to the fenestration and/or resection of pineal cysts. Preoperative considerations include patient presentation, anticipated disease and vascularity, degree of local venous anatomical distortion, and selection of optimal paramedian trajectory.

Supraorbital endoscopic approach to colloid cysts

BACKGROUND

Surgical approaches to colloid cysts of the third ventricle have evolved over time. In recent years, endoscopy has been recognized as an effective alternative to open surgery. The disadvantage of endoscopic treatment is the difficulty in controlling the adhesion of the cyst to the roof of the third ventricle and in obtaining complete removal of the cyst.

OBJECTIVE

To design and carry out a supraorbital approach to obtain a better viewing angle of the cyst and better control of the adhesion of the cyst to the roof of the third ventricle.

METHODS

From September 2005 to February 2008, we operated on 7 consecutive patients with colloid cysts in the third ventricle. All procedures were performed with the endoscopic supraorbital approach. The endoscopic procedure was performed with a rigid STORZ endoscope with 3 working channels. In 4 patients, the surgical supraorbital trajectory was planned with the help of a navigator.

RESULTS

The procedures lasted between 60 and 110 minutes, including the registration on the navigation system. Near-total removal of the cyst was achieved in 6 patients. All patients were discharged within 6 days.

CONCLUSION

Endoscopic treatment may be an effective and safe alternative to open surgical craniotomy. Our series shows that the endoscopic supraorbital endoscopic resection is a valuable approach to colloid cysts of the third ventricle.

Stereotactically guided endoscopic port surgery for intraventricular tumor and colloid cyst resection

BACKGROUND

Intraventricular lesions are challenging entities that may be difficult to resect completely and safely, especially larger lesions with high vascularity or firm consistency.

OBJECTIVE

To assess the results of stereotactically guided endoscopic port (SEP) surgery for resection of colloid cysts and intraventricular tumors.

METHODS

The authors developed a minimally invasive microsurgical technique for intraventricular surgery using parallel endoscopy to visualize the lesion. Surgical resection was performed via an 11.5-mm transparent conduit (Neuroendoport) deployed under stereotactic guidance. Forty-seven consecutive cases were performed, and all had a minimum 1-year follow-up to assess the efficacy of the technique.

RESULTS

For colloid cysts, gross total resection was achieved in 31 (96.9%) of the 32 cases. The transient neurologic morbidity rate was 9.4%; no permanent neurologic morbidity occurred. For intraventricular tumors, gross or near total resection was achieved in 80% of cases. The transient neurological morbidity rate was 6.7%, and no permanent neurological morbidity occurred.

CONCLUSION

SEP surgery for colloid cysts and intraventricular tumors proved to be a safe and effective alternative to conventional microsurgical resection. This technique was not limited by the vascularity, friability, or size of any of the lesions.

Pediatric colloid cysts of the third ventricle: management considerations

PURPOSE

Pediatric colloid cysts (CC) have a congenital origin, and yet, there are very few studies focussing exclusively on their occurrence in the pediatric population. Pediatric CC has been associated with more aggressive clinical and radiological patterns than their adult counterparts. In this study, undertaken on children with anterior third ventricular CC, excised using the interhemispheric transcallosal approach, the characteristic clinicoradiological features and management options are studied.

METHODS

Five pediatric patients (aged 16 years or less; mean age 13.8 years; mean duration of symptoms:7.6 months) out of 38 patients with CC operated between 1995 to 2009 were included. The clinical manifestations included those of raised intracranial pressure (n = 4); exacerbation of occipital headache on reading (n = 1); secondary optic atrophy (n = 3); and, drop attacks (n = 1). On computed tomography scan, the cyst was hyperdense, enhancing in two patients and not enhancing in three patients. All had bilateral lateral ventricular dilatation with periventricular lucency. On magnetic resonance imaging (n = 3), the cyst was T1 hypointense and T2 isointense in one, hyperintense on both T1 and T2 with a hypointense capsule and nonenhancing on contrast in one (with a giant colloid cyst), and T1 hyperintense and T2 hypointense in one patient. An interhemispheric, transcallosal trajectory combined with transforminal approach (n = 3); combined transforminal and subchoroidal approaches (n = 1); and, interforniceal approach (n = 1) were used.

RESULTS

Total excision was performed in four patients. In one patient, a small part of capsule was left attached to thalamostriate vein. Symptoms of raised intracranial pressure showed improvement in all the patients with resolution of hydrocephalus. There was no tumor recurrence at follow-up.

CONCLUSIONS

Pediatric colloid cysts are rarer than their adult counterparts due to their late detection only after manifestations of raised intracranial pressure, visual or cognitive dysfunction or drop attacks occur. Their radiological appearance varies depending upon the amount of mucoid content, cholesterol, proteins, and water content. The fast development of clinical manifestations in children may be related to rapid enlargement of cyst due to higher water content within them. The transcallosal approach is the "gold standard" of surgery and usually ensures gratifying and lasting results.

Microsurgical Excision of Colloid Cyst With Favorable Cognitive Outcomes and Short Operative Time and Hospital Stay

OBJECTIVE

Microsurgical and endoscopic colloid cyst excision differ with regard to operative time, length of hospital stay, and extent of resection.

METHODS

A retrospective review of a single surgeon's microsurgical colloid cyst resection in 10 consecutive patients was performed. Cyst size, hydrocephalus, symptoms, operative time, postoperative stay, complications, and objective testing of memory, concentration, calculation, and attention (cognition), along with performance at job, were noted.

RESULTS

All 10 patients had complete excision. Mean cyst size, mean operative time, and median postoperative stay were 1.6 cm, 124 minutes, and 3.5 days respectively. The mean operative time from cyst visualization to complete excision was 18 minutes. Follow-up ranged from 6 to 111 months (mean, 49.5 months). There were no recurrences; symptoms (headache, visual and balance problems) improved significantly in 70%. Postoperative cognitive performance, including memory, was the same in 8 patients (5 of whom had preoperative memory problems) and worse in 2 patients who had no preoperative memory problems. The bone flap was removed in 1 patient for wound dehiscence. Hemiparesis in another patient, seen immediately after surgery, completely resolved before discharge. One patient with loculated ventricles and multiple previous shunt revisions had unresolved hydrocephalus after cyst excision.

CONCLUSION

We report the very short operative times and postoperative stay for microsurgery, which are comparable to some endoscopic series. We also report results of objective tests of cognitive performance. With adoption of a callosal incision of 1 cm or less, meticulous dissection around the fornix, and complete excision, acceptable long-term cognitive function and functional performance were achieved. Our results support the microsurgical approach. A larger sample size can more conclusively establish whether it should be chosen over the endoscopic technique.

Dizygotic twins with a colloid cyst of the third ventricle: case report

OBJECTIVE AND IMPORTANCE

Colloid cysts of the third ventricle are rare benign tumors of endodermal origin accounting for 1% of all intracranial tumors. Interestingly, a few familial cases have been reported previously. We present the first case of dizygotic twins with a symptomatic colloid cyst of the third ventricle.

CLINICAL PRESENTATION

A 10-year-old boy was admitted to a local hospital in 1993 because of severe progressive headache. Computed tomographic and magnetic resonance imaging scans revealed acute obstructive hydrocephalus attributable to a third ventricular colloid cyst, which was removed after emergent ventricular drainage. Fourteen years later, a nonidentical twin brother complained of continuous headache with nausea and vomiting. A magnetic resonance imaging scan showed obstructive hydrocephalus and a third ventricle colloid cyst, which was removed by use of the transcallosal approach.

INTERVENTION

Both twins underwent complete removal of the cyst by the interhemispheric transcallosal approach without postoperative complications.

CONCLUSION

On the basis of a literature review, 2 cases of colloid cysts of the third ventricle in monozygotic twins and a few familial cases have been reported. Our case is the first in dizygotic twin brothers. These findings suggest that the prevalence of colloid cyst may be higher in twins than in the general population. We believe that the presence of this lesion in a twin necessitates magnetic resonance imaging of the other twin, and a clinical follow-up would be recommended in all other first-degree relatives.

APPLICATION OF NEUROENDOSCOPY TO INTRAVENTRICULAR LESIONS

WE PRESENT AN overview of the history, development, technological advancements, current application, and future trends of cranial endoscopy. Neuroendoscopy provides a safe and effective management modality for the treatment of a variety of intracranial disorders, either tumoral or non-tumoral, congenital, developmental, and degenerative, and its knowledge, indications, and limits are fundamental for the armamentarium of the modern neurosurgeon.

Complete Microsurgical Resection of Colloid Cysts with a Dual-port Endoscopic Technique

Objective:

A dual-port endoscopic approach, used for the surgical management of colloid cysts, was developed with the following goals: 1) a direct, unobstructed, high-illumination endoscopic view of the attachment point of the colloid cyst to the tela choroidea, and 2) a gross total resection of the colloid cyst capsule using microsurgical techniques.

Methods:

Eleven symptomatic, hydrocephalic, colloid cyst patients who underwent operation with a unilateral, precoronal-frontopolar dual-port endoscopic technique were retrospectively assessed. Preoperative magnetic resonance imaging scans were analyzed, comparing the lateral precoronal to the frontopolar approach, to determine the degree of angulation that would be required to directly view the roof of the third ventricle. Clinical outcome and radiographical follow-up were assessed.

Results:

The frontopolar approach achieved an approach angle to the roof of the third ventricle of only 15 ± 4 degrees compared with 56 ± 6 degrees (P< 0.0001) for the precoronal approach. The view obtained from the frontopolar endoscope allowed excellent visualization of the cyst attachment point. Microsurgical dissection techniques, using many standard microsurgical instruments introduced through the second port, were satisfactorily accomplished. Complete resections were obtained in 10 out of 11 dual-port patients. Worsening of memory deficits occurred in one patient. There was no cyst recurrence with a mean follow-up period of 26 ± 27 months.

Conclusion:

The dual-port endoscopic technique described is an alternative to classic microsurgical craniotomy approaches. The technique allows excellent visualization of the colloid cyst attachment and permits microdissection techniques.