Interactive Image-Guided Management of Colloid Cysts of the Third Ventricle

Endoscopic Colloid Cyst Resection in the Absence of Ventriculomegaly

BACKGROUND:

The absence of ventriculomegaly has been considered an overt or relative contraindication to the endoscopic resection of colloid cysts. In the past, endoscopic removal of colloid cysts in the absence of ventriculomegaly has been considered ill advised. Reports of successful endoscopic surgery in small ventricles are surfacing.

OBJECTIVE:

We examined the combined experience of 2 high-volume endoscopic centers to characterize the outcomes of patients undergoing endoscopic removal of colloid cysts in small ventricles.

METHODS:

We retrospectively reviewed all endoscopic colloid cyst removal procedures by the 2 senior authors (P.N., C.T.) performed at the Barrow Neurological Institute over an 8-year period. Radiographic, clinical, and interview data were recorded and analyzed. The age-adjusted relative bicaudate index was used to define small ventricles.

RESULTS:

Sixteen patients (8 female) underwent attempted endoscopic removal of a colloid cyst in the absence of ventriculomegaly. Surgery was technically successful in 15 patients. The cyst was removed completely in 13 of patients. Short-term memory loss was initially present in 3 patients and completely resolved in all but 1 patient who had presented with short-term memory loss. Temporary complications occurred in 2 patients.

CONCLUSION:

Normal-size ventricles are not a contraindication to endoscopic removal of third ventricular colloid cysts. Complication rates are at least comparable to those of patients with ventriculomegaly or to those undergoing open microsurgical resection.

Treatment of colloid cysts of the third ventricle through neuroendoscopic Nd: YAG laser stereotaxis

OBJECTIVE: Colloid cysts (IIIVT CC) are benign neuroepithelial cysts located in the anterior third ventricle. The authors propose the use of Nd:YAG laser stereotactic neuroendoscopic for guided resection of the third ventricle colloid cysts. METHOD: Eleven patients presented third ventricle colloid cysts and were treated by Nd:YAG laser guided with stereotactic endoscopy (n=7) , stereotactic endoscopy (n=3) or stereotactly guided puncture (n=1). The patients were followed prospectively (average 33 months, range 19-64 months). The clinical data, neuroimaging findings, hospitalization stay, outcomes and complications of the method were evaluated. RESULTS: All patients presented headache; six had papilledema, one had gait disturbance and one had third-nerve palsy. Neuroimaging showed hydrocephalus and a IIIVT CC with 14.4-mm mean diameter. After surgery all patients presented clinical and image improvement. Only two patients presented transient morbidities that were easily treated: One had diabetes insipidus that lasted for two days and was treated with a single dose of DDAVP, and another had chemical aseptic meningitis, probably due to the contact of the cyst content with the CSF. This patient was treated with antibiotics and corticosteroids with complete resolution of the problem without sequels. The other patients were discharged from the hospital 48 h after surgery. CONCLUSION: The stereotactic neuroendoscopy-guided procedure with Nd:YAG laser allowed the complete removal of the third ventricle colloid cysts, without definitive morbidities, sequels or recurrence of the lesion.

Interhemispheric transcallosal subchoroidal fornix-sparing craniotomy for total resection of colloid cysts of the third ventricle

OBJECT

Endoscopic surgery has been reported to be more cost-effective and safer than open craniotomy for resection of colloid cysts, despite a 5-10% conversion rate to craniotomy, a 5% recurrence rate, a 5-10% ventricular shunting rate, a 5-10% epilepsy rate, and a 3-4 day hospital stay. In 1985, the authors developed a interhemispheric, transcallosal, subchoroidal, fornix-sparing approach that allowed safe total resection of the colloid cyst and that appeared to be superior to the endoscopic approach. The long-term results are analyzed and compared with findings in the literature.

METHODS

Fifty-seven consecutive colloid cysts were totally removed via a 3 x3-in paramedian craniotomy flap and a microscopic interhemispheric, transcallosal, subchoroidal approach sparing the ipsilateral fornix. The length of the callosotomy was 1.5-2 cm in all patients. The mean follow-up duration was 12 years (range 2-22 years). A retrospective analysis comparing the authors' results with those reported in the endoscopic literature was performed.

RESULTS

All patients had 1-year postoperative imaging studies (CT or MR imaging) documenting gross-total resection with no deaths, infection, hemiparesis, seizures, or disconnection syndrome. One surgery was complicated by bilateral subdural hematomas, which were successfully treated. There has been a zero recurrence rate. Three patients required a permanent ventriculoperitoneal shunt (including 2 who required emergency ventriculostomy before surgery). The mean hospital stay was 4.8 days (range 2-24 days). There was 1 patient with permanent short-term memory loss who presented with a herniation syndrome requiring emergency ventriculostomy.

CONCLUSIONS

The interhemispheric, transcallosal, subchoroidal, fornix-sparing approach to gross-total resection of colloid cysts is safe and led to a zero recurrence rate with no permanent neurological sequelae including epilepsy, and these results are superior to any reported results with endoscopy.

Purely endoscopic resection of colloid cysts

OBJECTIVE

To further assess the safety and long-term efficacy of endoscopic resection of colloid cysts of the third ventricle.

METHODS

A retrospective review of a series of 35 consecutive patients (18 male, 17 female) with colloid cysts treated by endoscopic surgery was undertaken.

RESULTS

The mean patient age was 32.4 years (range, 11-54 yr). Headache was the most common presenting symptom (22 patients). The average tumor size was 18 mm (range, 3-50 mm). The endoscopic technique could not be completed in six patients, necessitating conversion to an open craniotomy and a transcortical approach to the colloid cyst. All patients had histologically confirmed colloid cysts of the third ventricle, and complete resection of the lesion was confirmed macroscopically and radiologically in all patients. There were no deaths. Two patients developed aseptic meningitis without any permanent sequelae. One patient developed unilateral hydrocephalus attributable to obstruction of the foramen of Monro, which was treated with endoscopic septum pellucidotomy. The median follow-up period was 88 months (range, 10-132 mo). There was one asymptomatic radiological recurrence. No seizures occurred after surgery.

CONCLUSION

The results of this study support the role of endoscopic resection in the treatment of patients with colloid cysts as a safe and effective modality. In some cases, conversion to an open procedure may be required. Additional follow-up will be required to continue to address the duration of lesion-free survival.

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.

Endoscopic and stereotactic neurosurgery

PURPOSE OF REVIEW

Review of the anesthetic considerations for neuroendoscopy and stereotactic procedures.

RECENT FINDINGS

Minimally invasive procedures are increasingly applied in novel ways in the diagnosis and treatment of neurological pathologies. Endoscopic third ventriculostomy, endoscopic shunt revisions and drainage of intraventricular hematoma using a neuroendoscope have become routine neurosurgical procedures. Stereotaxis has expanded its scope from simple brain biopsy to functional neurosurgery and psychiatry. While these procedures are 'minimally invasive', perioperative critical events may still occur.

SUMMARY

Vigilance in preoperative assessment and intraoperative monitoring is essential in minimizing perioperative morbidity and mortality in patients undergoing neuroendoscopic and stereotactic procedures.