A flexible endoscope-assisted interhemispheric transcallosal approach through the contralateral ventricle for the removal of a third ventricle craniopharyngioma: A technical report

A Novel Foley Catheter-Based Brain Retraction Method for the Interhemispheric Approach: Technical Considerations and an Illustrative Video

BACKGROUND

Management of interhemispheric pathologies requires surgical intervention through a restricted anatomical corridor ensconced within critical cerebral structures. The use of retractors to facilitate operative access may cause damage to cerebral tissue. The development of an innovative retraction technique designed to alleviate cerebral damage in such cases is imperative. In this study, we present a novel and gentle retraction method to facilitate the interhemisferic approach.

METHODS

We retrospectively examined data of 9 right-handed patients who underwent surgical resection of interhemispheric lesions between 2021 and 2022. All patients underwent surgery for the first time because of this pathology. All operative specimens were histologically confirmed. Clinical characteristics, operative details, and follow-up data were retrospectively analyzed.

RESULTS

The new retraction technique was successfully applied to 8 tumor patients and 1 patient with an aneurysm. Eight patients had an anterior interhemispheric approach, and 1 patient had a posterior interhemispheric approach. Complete surgical excision was achieved in all patients with no postoperative complications. Postoperative Gadolinium (Gd)-enhanced magnetic resonance imaging (MRI) showed no signs of ischemia or contusion. All patients exhibited significant improvements in their symptoms. An illustrative video that elucidates the removal of an interhemispheric epidermoid tumor, employing the anterior ipsilateral interhemispheric approach, featuring the novel retraction method.

CONCLUSIONS

The ideal retraction technique during the interhemispheric approach is still a challenge. Our novel retraction technique may help minimize brain parenchymal damage during surgical resection of interhemispheric lesions.

Interhemispheric Transcingulate Sulcus Approach to Deep-Seated Medial Frontal and Parietal Lesions-Fiber Dissection Study With Illustrative Cases

BACKGROUND

Surgery for lesions located in the medial frontal and parietal lobes can be quite challenging for neurosurgeons because of morbidities that may arise from damage to critical midline structures or intact neural tissue that need to be crossed to reach the lesion. In our anatomic studies, the cingulate sulcus was observed as an alternative access route for lesions located in medial frontal and parietal lobes.

OBJECTIVE

To explain the microsurgical anatomy of the medial hemisphere and cingulate sulcus and to demonstrate the interhemispheric transcingulate sulcus approach (ITCSA) with 3 clinical cases.

METHODS

Five formalin-fixed brain specimens, which were frozen at -18 °C for at least 2 weeks and then thawed under tap water, were gradually dissected from medial to lateral. Diffusion fiber tracking performed using DSI Studio software in data was provided by the Human Connectome Project. Clinical data of 3 patients who underwent ITCSA were reviewed.

RESULTS

Cingulate sulcus is an effortlessly identifiable continuous sulcus on the medial surface of the brain. Our anatomic dissection study revealed that the lesions located in the deep medial frontal and parietal lobes can be reached through the cingulate sulcus with minor injury only to the cingulum and callosal fibers. Three patients were treated with ITCSA without any neurological morbidity.

CONCLUSION

Deep-seated lesions in the medial frontal lobe and parietal lobe medial to the corona radiata can be approached by using microsurgical techniques based on anatomic information. ITCSA offers an alternative route to these lesions besides the known lateral transcortical/transsulcal and interhemispheric transcingulate gyrus approaches.

THIRD VENTRICLE CRANIOPHARYNGIOMA INTRAVENTRICULAR TUMOR: A CASE REPORT AND A BRIEF LITERATURE REVIEW

Craniopharyngioma is a rare embryonic malformation, usually benign, of the sellar or parasellar regions. In this study, an uncommon case of third ventricle craniopharyngioma and a succinct review of its prevalence are presented. Even with low mortality rates, these injuries involve a high degree of endocrinological, visual, and neuropsychological morbidities, which have a huge impact on the patient's quality of life. Thus, surgical resection is the preferred therapy for tumors that compromise the flow of cerebrospinal fluid. However, due to the location of the craniopharyngioma, surgical management is accompanied by the risk of injury to important adjacent areas with postoperative repercussions. Therefore, the neurosurgeon's experience and the choice of the best surgical approach, are crucial for increasing prognosis.

Intraventricular Craniopharyngiomas-Overcoming Their Relative Inaccessibility: Institutional Experience With a Review of Literature

Introduction: Craniopharyngiomas constitute 2-4% of intracranial neoplasms. Intraventricular craniopharyngiomas (IVCrs) are the rarely encountered varieties of these lesions. Objective: The objective of the study was to study the special features in clinical presentation, imaging, management, and surgical outcome of IVCrs. Materials and Methods: This retrospective analysis included the combined experience from two tertiary care institutions. Medical records of histopathologically proven cases of IVCrs from January 1994 to June 2021 were assessed, and images were analyzed based on the criteria by Migliore et al. for inclusion of solely intraventricular lesion with the third ventricular ependyma demarcating it from the suprasellar cistern. Results: Among the 25 patients included (mean age: 35.4 years), the most common presentation included headache (n = 21, 84%), vomiting and other features of raised ICP (n = 18, 72%), visual complaints (n = 12, 48%), and endocrinopathies (n = 11, 44%). Fifteen had predominantly cystic tumors, two were purely solid, and eight were of mixed consistency. Primary open microsurgical procedures were performed in 18 (72%) patients, of which four (16%) were endoscope-assisted. Seven (28%) underwent a purely endoscopic procedure. One underwent a staged surgery with endoscopic cyst fenestration and intracystic interferon (IFN)-alpha therapy, followed by microsurgical excision. Complete excision was achieved in 10 patients, near-total in nine, and partial excision in six. Four patients underwent a ventriculoperitoneal shunt (one before the definitive procedure). At a median follow-up of 36 months (range:11-147 months), five patients developed a recurrence, and one had a stable small residue. This patient and two others with small cystic recurrences were observed. One patient was managed with radiotherapy alone. Another underwent re-surgery after a trial of radiotherapy, and the last patient developed a local recurrence, which was managed with radiotherapy; he then later developed an intraparenchymal recurrence, which was operated. Conclusion: Purely IVCrs present with raised intracranial pressure, and visual disturbances are less common. Their deep-seated location and limited surgical field-of-view makes minimally invasive endoscopic-assisted surgery most suitable for their excision. The thin-walled cystic lesions may be occasionally adherent to the ependymal wall in close vicinity to the thalamus-hypothalamus complex, making complete excision difficult. Their responsiveness to radiotherapy, often leads to a gratifying long-term outcome.

Intraventricular neuroepithelial tumors: surgical outcome, technical considerations and review of literature

Background

Intraventricular neuroepithelial tumors (IVT) are rare lesions and comprise different pathological entities such as ependymomas, subependymomas and central neurocytomas. The treatment of choice is neurosurgical resection, which can be challenging due to their intraventricular location. Different surgical approaches to the ventricles are described. Here we report a large series of IVTs, its postoperative outcome at a single tertiary center and discuss suitable surgical approaches.

Methods

We performed a retrospective chart review at a single tertiary neurosurgical center between 03/2009–05/2019. We included patients that underwent resection of an IVT emphasizing on surgical approach, extent of resection, clinical outcome and postoperative complications.

Results

Forty five IVTs were resected from 03/2009 to 05/2019, 13 ependymomas, 21 subependymomas, 10 central neurocytomas and one glioependymal cyst. Median age was 52,5 years with 55.6% (25) male and 44.4% (20) female patients. Gross total resection was achieved in 93.3% (42/45). 84.6% (11/13) of ependymomas, 100% (12/21) of subependymomas, 90% (9/10) of central neurocytomas and one glioependymal cyst were completely removed. Postoperative rate of new neurological deficits was 26.6% (12/45). Postoperative new permanent cranial nerve deficits occurred in one case with 4th ventricle subependymoma and one in 4th ventricle ependymoma. Postoperative KPSS was 90% (IR 80–100). 31.1% of the patients improved in KPSS, 48.9% remained unchanged and 20% declined. Postoperative adverse events rate was 20.0%. Surgery-related mortality was 2.2%. The rate of shunt/cisternostomy-dependent hydrocephalus was 13.3% (6/45). 15.4% of resected ependymomas underwent adjuvant radiotherapy. Mean follow-up was 26,9 (±30.1) months.

Conclusion

Our surgical findings emphasize satisfactory complete resection throughout all entities. Surgical treatment can remain feasible, if institutional experience is given. Satisfying long-term survival and cure is possible by complete removal. Gross total resection should always be performed under function-remaining aspects due to mostly benign or slow growing nature of IVTs. Further data is needed to evaluate standard of care and alternative therapy options in rare cases of tumor recurrence or in case of patient collective not suitable for operative resection.

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.

Preoperative Assessment of Craniopharyngioma Adherence: Magnetic Resonance Imaging Findings Correlated with the Severity of Tumor Attachment to the Hypothalamus

BACKGROUND AND OBJECTIVE

Craniopharyngioma (CP) adherence represents a heterogeneous pathologic feature that critically influences the potentially safe and radical resection. The aim of this study was to define the magnetic resonance imaging (MRI) predictors of CP adherence severity.

METHODS

This study retrospectively investigated a cohort of 200 surgically treated CPs with their corresponding preoperative conventional MRI scans. MRI findings related to the distortions of anatomic structures along the sella turcica-third ventricle axis caused by CPs, in addition to the tumor's shape and calcifications, were analyzed and correlated with the definitive type of CP adherence observed during the surgical procedures.

RESULTS

CP adherence is defined by 3 components, as follows: 1) the specific structures attached to the tumor, 2) the adhesion's extent, and 3) its strength. Combination of these 3 components determines 5 hierarchical levels of adherence severity with gradually increasing surgical risk of hypothalamic injury. Multivariate analysis identified 4 radiologic variables that allowed a correct overall prediction of the levels of CP adherence severity in 81.5% of cases: 1) the position of the hypothalamus in relation to the tumor-the most discriminant factor; 2) the type of pituitary stalk distortion; 3) the tumor shape; and 4) the presence of calcifications. A binary logistic regression model including the first 3 radiologic variables correctly identified the CPs showing the highest level of adherence severity (severe/critical) in almost 90% of cases.

CONCLUSIONS

A position of the hypothalamus around the middle portion of the tumor, an amputated or infiltrated appearance of the pituitary stalk, and the elliptical shape of the tumor are reliable predictors of strong and extensive CP adhesions to the hypothalamus.

Efficacy and Complications of Endoscopic Skull Base Surgery for Giant Pituitary Adenomas

OBJECTIVE

We report surgical results and complications of endoscopic endonasal skull base surgery for giant pituitary adenomas.

METHODS

This study included 34 pituitary adenomas >40 mm treated by endoscopic endonasal skull base surgery between 2002 and 2015. Removal rates, symptoms, and complications were analyzed by direction of tumor extension.

RESULTS

Average tumor size was 45.5 mm. Near-total resection was achieved in 16 of 34 (47.1%) cases. Near-total resection was achieved significantly more often in anterior extension types and round tumor in superior extension types compared with multiple extension types. The average residual amount in 18 partial resection cases was 30.2% of preoperative volume, with no significant difference between groups. Regrowth after partial resection occurred in 8 cases, but repeated surgery or stereotactic radiotherapy controlled tumor growth and improved symptoms. Postoperative improvement of visual field deficits was achieved in 23 of 25 (92.0%) cases. Postoperative complications included visual deterioration (n = 1), cerebrospinal fluid leakage (n = 2), and cerebral infarction secondary to perforator injury (n = 2). Symptomatic intratumoral hemorrhage occurred in 1 multiple extension type.

CONCLUSIONS

Endoscopic endonasal skull base surgery enables less invasive and safer removal of various extension types of giant pituitary adenomas. Preservation of visual function is essential. Two-stage surgery or partial resection with additional treatments is possible without complications if a sufficient amount of resection is performed. In cases in which insufficient resection may be expected, alternative treatment, including combined-simultaneous resection, should be considered.