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

How I do it: endoscopic evacuation of intraventricular lesions using a flexible endoscope in combination with an angiographic catheter

BACKGROUND

In intraventricular surgery using a flexible endoscope, the lesion is usually aspirated via the working channel. However, the surgical view during aspiration is extremely poor because the objective lens is located adjacent to the working channel.

METHOD

To address this issue, we developed a novel surgical procedure using an angiographic catheter. In this procedure, the catheter is inserted into the working channel, and the lesion is aspirated through the catheter. Besides, continuous intraventricular irrigation is performed via the gap between the catheter and the working channel.

CONCLUSION

This procedure maintains a clear view during surgery and reduces complications.

Isolated entrapment of the lateral ventricle after neuroendoscopic resection of colloid cysts: single - center experience and management

BACKGROUND

A minimally invasive option of colloid cyst surgical treatment is endoscopic resection, well validated in various reports and clinical practice. A rare complication of the surgical treatment, previously reported only once in literature, is the entrapment of the lateral ventricle. In this study we aim to outline our experience in the management of this occurrence, hypothesizing possible etiopathogenetic causes.

METHODS

Among patients who underwent neuroendoscopic resection for a colloid cysts at our Institution between 2013 and 2022, cases who developed a postoperative lateral ventricle entrapment were retrospectively reviewed and included. Clinical history, imaging and treatment were reported.

RESULTS

Among 34 patients treated for a colloid cysts, two (5.9 %) patients developed an ipsilateral ventricular entrapment with dilation from two to five months after the resection. Both patients were substantially asymptomatic and neurologically intact, and therefore treated conservatively. One case underwent complete spontaneous radiological resolution one month later, and the other one has remained neurological asymptomatic at follow-up.

CONCLUSIONS

Isolated asymptomatic ventricular entrapment with significant dilation after endoscopic colloid cyst resection is a rare occurrence which can be plausibly caused by scar tissue at the level of the foramen of Monro. Because they can have an indolent course with spontaneous resolution, conservative treatment is a viable option, with strict radiological and clinical follow - up. Given the rarity of the occurrence, further studies with larger cohorts are warranted to confirm the etiopathogenetic hypothesis and validate the clinical management.

Trascallosal bilateral transforaminal resection of a solid partially calcified colloid cyst: 2D operative video

BACKGROUND

Colloid cysts are benign lesions of the roof of the third ventricle, often diagnosed incidentally; sometimes they can cause hydrocephalus due to obstruction of the foramina of Monroe. Symptomatic cysts could be resected either microsurgically (transcallosal or transcortical) or endoscopically. Although both strategies are effective and have advantages and disadvantages, there is no consensus on the choice of the optimal approach. Transcallosal resection, although more invasive than endoscopy, allows adequate bimanual manipulation of the cyst and is associated with high rates of complete resection, the use of neuronavigator and intraoperative ultrasound optimizes surgical trajectory and improves safety of the procedure with complication rates comparable to endoscopy. Endoscopy is less invasive but complete resection of solid cysts can be challenging.

CASE DESCRIPTION

In Video 1, we show resection of a solid partially calcified colloid cyst using a transcallosal bilateral transforaminal approach to anterior third ventricle male, 65 years old; headache and mild memory impairment for 6 months; admitted at our emergency department because of a brief loss of consciousness. Neurologic examination was normal. Computed tomography (CT) and magnetic resonance imaging (MRI) showed a colloid cyst at the level of anterior third of the third ventricle (1.5 cm in diameter) with hypointense appearance in T2 sequences suggesting a solid calcific component. The ventricular system was enlarged. Colloid cyst risk score 3/5 (diameter >0.7 cm, headache, risk zone I) considered an intermediate-risk subgroup according to Alford et al. On this basis, we proposed the surgical treatment. We chose a transcallosal microsurgical resection. The patient gave consent for the procedure. A preoperative planning with a computer-generated 3D model is performed to simulate the approach. Craniotomy, interhemispheric dissection, and callosotomy were planned with the neuronavigator and with the aid of intraoperative ultrasound to optimize the trajectory and perform a limited and tailored callosotomy. The 1.5 cm callosotomy allows to approach both lateral ventricles, the cyst was progressively dissected working bilaterally through both foramina of Monroe without injuries of the fornices. Resection at term is complete. Postoperative MRI and CT scan confirmed complete excision without complications; the patient was discharged after a week in good neurological condition with complete regression of headache.

CONCLUSION

Microscopic transcallosal resection of the colloid cyst of the third ventricle allows for complete resection with low complication rates. The use of preoperative 3D planning and integrated neuronavigation with intraoperative ultrasound helps to reduce invasiveness.

Outcomes and complications of microscopic transcallosal colloid cyst resection: A single institution experience

Background:

Colloid cysts have always provoked the interest of neurosurgeons due to their benign histology, wide variety of clinical presentations, and differences in reported surgical outcomes. Although recent studies have reported favorable outcomes with different surgical resection approaches, the transcallosal approach remains the most popular approach to date. In this series, we report the clinical and radiological outcomes of the transcallosal approach for the resection of third ventricle colloid cysts in 12 patients.

Methods:

We present a case series of 12 patients who were radiologically diagnosed with a third ventricle colloid cyst who underwent transcallosal resection by a single surgeon in one center over a 6-year period. Clinical, radiological, and surgical data were collected, and surgical outcomes and complications were analyzed.

Results:

Of the 12 patients diagnosed with colloid cysts, 10 (83%) presented with headache, and five (41%) presented with memory disturbance. All 12 patients showed improvement or resolution of their symptoms following resection. Nine patients (75%) presented with hydrocephalus on radiology. All the patients required preoperative or intraoperative external ventricular drain insertion. Four patients (33%) experienced transient postoperative complications. None of the patients required long-term cerebrospinal fluids shunting. One (8%) of 12 patients experienced transient memory loss. No mortality was recorded during the follow-up.

Conclusion:

Transcallosal resection of colloid cysts has a favorable prognosis. It allows for complete resection of the cyst with minimal transient postoperative complications. Most patients with postoperative complications show complete resolution of symptoms, with no long-term morbidity.

Anterior Inter-hemispheric Transcallosal Approach for Resection of Colloid Cyst: A Video Abstract

Background Although histologically benign, colloid cysts have been an entity of interest to neurosurgeons due to the wide array of possible presentations ranging from asymptomatic to high ICP symptoms to sudden death. It is estimated that colloid cysts represent 0.3 to 2% of all brain tumors.1

As they are typically located in the third ventricle, multiple approaches have been adapted and developed for the maximum resection with the least complications given the sensitive anatomy in the area.1 2 The interhemispheric transcallosal approach can be safely performed to fully resect a third ventricle colloid cyst with close to zero recurrence rate and minimal to none permanent deficits.3 This video is an educational illustration of the surgical technique and the related anatomy for the interhemispheric transcallosal approach and how to provide best chances of a benign postoperative course.

Case Description In this surgical video, we present a case of a 20-year-old male, a known case of hypertension and un-controlled diabetes type-1, presented to our hospital with on and off headache, dizziness, and diplopia that gradually progressed. His neurological exam was unremarkable including memory function. CT and MRI scans demonstrated a rounded sharply demarcated lesion at the at the roof of the third ventricle, measuring 1 × 1 cm in size. The patient underwent an anterior inter-hemispheric transcallosal approach, with gross total resection of the cyst. In the follow-up office visit, the patient headache has resolved, and he had no seizures with preserved memory functions.

Conclusion When removal of the colloid cyst is indicated, the interhemispheric transcallosal approach can be performed safely with gross total resection and minimal neurological deficit. This is a surgical demonstration of the transcallosal approach showcasing the surgical corridors and related anatomy.

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.

Neuronavigation-Guided Transcortical-Transventricular Endoport-Assisted Endoscopic Resection for Thalamic Lesions: Preliminary Experience

BACKGROUND

Surgery for thalamic lesions is generally challenging because they are deep-seated lesions surrounded by vital neurovascular structures. Whether neuronavigation-guided transcortical-transventricular endoport-assisted endoscopic resection for thalamic lesions is feasible remains to be further evaluated.

METHODS

A retrospective review of 8 who patients received neuronavigation-guided transcortical-transventricular endoport-assisted endoscopic resection for thalamic lesions was performed. Preoperative and tumor-related variables and postoperative outcomes were analyzed.

RESULTS

All lesions were located in the medial part of the thalamus, and most of them expanded forward, downward, or backward. Median size of lesions was 31 mm (range, 16-52 mm). Final pathology results confirmed that 1 case was a cavernous malformation, 3 were pilocytic astrocytomas, and 4 were glioblastomas. None of the patients had postoperative seizures. Gross total resection and long-term postoperative survival were achieved in all patients with benign lesions, while near-total resection (>90%) was achieved in 3 of 4 patients (75%) with glioblastoma, and subtotal resection (<90%) was achieved in 1 patient (25%). Among patients with glioblastoma, 1 patient remained free of recurrence at 16 months of follow-up; the other 3 patients had worse Karnofsky performance scale scores after surgery and died within 6 months.

CONCLUSIONS

Combining the advantages of neuronavigation, endoscopy, and endoport techniques via the middle frontal gyrus approach can safely and effectively remove benign lesions in the medial part of the thalamus. This procedure can also be performed in well-selected cases of glioblastoma and likely confers a survival advantage for this rapidly and universally fatal disease.

Structural Brain Network Reorganization Following Anterior Callosotomy for Colloid Cysts: Connectometry and Graph Analysis Results

Introduction:

The plasticity of the neural circuits after injuries has been extensively investigated over the last decades. Transcallosal microsurgery for lesions affecting the third ventricle offers an interesting opportunity to investigate the whole-brain white matter reorganization occurring after a selective resection of the genu of the corpus callosum (CC).

Method

Diffusion MRI (dMRI) data and neuropsychological testing were collected pre- and postoperatively in six patients with colloid cysts, surgically treated with a transcallosal-transgenual approach. Longitudinal connectometry analysis on dMRI data and graph analysis on structural connectivity matrix were implemented to analyze how white matter pathways and structural network topology reorganize after surgery.

Results

Although a significant worsening in cognitive functions (e.g., executive and memory functioning) at early postoperative, a recovery to the preoperative status was observed at 6 months. Connectometry analysis, beyond the decrease of quantitative anisotropy (QA) near the resection cavity, showed an increase of QA in the body and forceps major CC subregions, as well as in the left intra-hemispheric corticocortical associative fibers. Accordingly, a reorganization of structural network topology was observed between centrality increasing in the left hemisphere nodes together with a rise in connectivity strength among mid and posterior CC subregions and cortical nodes.

Conclusion

A structural reorganization of intra- and inter-hemispheric connective fibers and structural network topology were observed following the resection of the genu of the CC. Beyond the postoperative transient cognitive impairment, it could be argued anterior CC resection does not preclude neural plasticity and may subserve the long-term postoperative cognitive recovery.

Decision-Making and Management in a Patient With Coexistent Colloid Cyst and Pituitary Macroadenoma: A Case Report

The coexistence of separate and distinct primary intracranial tumors is rare. Specifically, there are no previous reports of a colloid cyst coexisting with a pituitary macroadenoma. We present the case of a 40-year-old male with a colloid cyst associated with mild enlargement of the right lateral ventricle and a coexistent pituitary macroadenoma with compression of the optic apparatus. An endoscopic endonasal transsphenoidal surgery (EETS) for resection of the pituitary mass was performed first due to the patient’s complaints of acute visual changes. He then underwent a right frontal craniotomy for resection of the colloid cyst one month later. The patient recovered without residual deficits in vision, and he did not require ventricular shunting after removal of the colloid cyst. We aimed to discuss our decision-making process and the management of these coexistent lesions.