Interhemispheric Transcallosal Research Articles

Posterior transcallosal intervenous-interforniceal approach to a periaqueductal tumor.

Described by Dandy in 1921, the posterior interhemispheric transcallosal approach provides an operative corridor to the pineal region, posterior third ventricle, and upper midbrain. Intervenous-interforniceal and paravenous-interforniceal variants have been utilized for midline and paramidline pathology, respectively. The intervenous-interforniceal variant capitalizes on the natural separation of the internal cerebral veins, which are found medial to the forniceal crura at this level, to provide a safe corridor to the tumor while minimizing the risk of injury to the fornices. Here, the authors describe a posterior interhemispheric transcallosal approach using the intervenous-interforniceal variant for resection of a periaqueductal pilocytic astrocytoma.The video can be found here: https://youtu.be/mtQKEXEveTg.

Left Interhemispheric Craniotomy for Resection of Cavernous Malformation: 2-Dimensional Operative Video.

Thalamic cavernous malformations pose variable surgical challenges given that the location and size of the lesion often determine the approach surgical trajectory. The patient in this case has a large thalamic cavernous malformation that results in a mass effect on the third ventricle and directly abuts the lateral ventricle. A small interhemispheric craniotomy is performed to allow for an anterior interhemispheric transcallosal approach to the lesion. The lateral ventricle is accessed, and the septum is removed to enhance visualization of the surgical field. A small rim of normal parenchyma on the lateral margin of the thalamus is transgressed, and the cavernous malformation is entered. The lesion is removed in a piecemeal manner. Use of counter traction assists with the piecemeal removal. The lighted suction is critical during inspection and manipulation of the lesion within the resection cavity given the limited lighting deep within the cavity. The lesion was removed completely, and postoperative imaging confirms gross total resection. The patient gave informed consent for surgery and video recording. The institutional review board approval was deemed unnecessary. Used with permission from the Barrow Neurological Institute.

A primary third ventricle mixed germ cell tumor with leptomeningeal dissemination of immature teratoma component

A 17-year-old male patient presented to the clinic with a headache, nausea, and vomiting. Magnetic resonance imaging demonstrated a fat-containing and -enhancing heterogeneous tumor in the third ventricle, and fat droplets within the ventricles and the subarachnoid space. Obstructive hydrocephalus was also present. Emergency subtotal removal of the mass was performed via interhemispheric transcallosal approach. The histopathological diagnosis was a mixed germ cell tumor that was composed of embryonal carcinoma, yolk-sac tumor, germinoma, and immature teratoma containing a large amount of mature elements. The patient was referred for postoperative chemoradiotherapy. A mixed germ cell tumor is a rare type of nongerminomatous germ cell tumor that is made up of at least two different types of germ cell tumors. These may include germinoma, choriocarcinoma, embryonal carcinoma, yolk sac tumor, mature teratoma, immature teratoma, or teratoma with malignant degeneration. As far as we know, this is the first reported case of a primary third ventricle mixed germ cell tumor with leptomeningeal dissemination of the immature teratoma component that contains grossly visible mature elements at admission.

Chordoid glioma of the third ventricle: A systematic review and single-center experience

BackgroundChordoid gliomas (CG) are neoplasms within the anterior part of the third ventricle. ObjectiveTo analyze all reported cases of CG with regard to imaging features, neurosurgical approaches, VP-shunt dependency, immunohistochemistry and follow-up. Furthermore, we present three cases. MethodsClinical symptoms, MRI features and immunohistochemistry were analyzed in 70 cases. Univariate analyses of extent of resection, surgical approaches, recurrence rates and postoperative hydrocephalus were performed. Three cases are reported with focus on clinical presentation, surgical results, immunohistochemistry and follow-up. ResultsHeadache (51.4%), visual deterioration (41.4%) and memory deficits (21.4%) are the main symptoms. MRI shows a homogenously enhancing solid mass in 84.8% with cysts in 20% of all reported cases. 20% of the patients treated by a subtotal resection (STR) and 0% by a gross total resection (GTR) had a recurrence (p = 0.034). VP-Shunt dependency was higher in the STR group (19.2%) compared with GTR group (5%; p = 0.067). Rate of GTR of the subfrontal trans-lamina terminalis route (83.3%) was superior to the interhemispheric transcallosal approach (23.1%; p = 0.041). GFAP (100%), Vimentin (100%) and CD 34 (69.6%) are the strongest immunohistochemical markers. Two female and one male patient were admitted to our department. However, in one case recurrence ouccured at 18 months after STR. ConclusionDespite the benign histopathology, CGs have high recurrence rates. Morphologically, CGs are solid homogenously enhancing tumors. GTR should be achieved, preferably by the trans-lamina terminalis route. Anatomy and immunohistochemistry seem to show tanycytic origin of this entity.

Endoscopic resection of the third ventricular epidermoid cysts: A case review and review of literature

Background:Epidermoid cysts are benign, congenital lesions that originate from ectodermal cells, they are most commonly found in the cerebellopontine angle, but rarely in the ventricular system. There is limited literature regarding the different microsurgical techniques utilized to approach these lesions.Methods:A 63-year-old female with a recurrent third ventricular epidermoid cyst underwent gross total resection utilizing an endoscopic technique. We also reviewed the various endoscopic/microsurgical approaches and outcomes reported in literature.Results:We identified 15 cases, including our own. Nine of these were managed using microsurgical techniques, while six cases (including ours) were treated endoscopically; gross total resection was achieved in 10/15 cases (67%). Most commonly, surgeons utilized the interhemispheric transcallosal approach (five cases). Tumor recurrence was seen in two cases. Complications attributed to these resections included: disorders of the hypothalamic-pituitary axis (3) – diabetes insipidus, galactorrhea, and hypopituitarism; tumor recurrence (2); aseptic meningitis (1); and a transient Korsakoff syndrome (1).Conclusion:Epidermoid cysts of the third ventricle are exceedingly rare, and surgical resection is generally well tolerated. Microsurgical transcortical, transcallosal, and endoscopic approaches each have advantages and disadvantages, and are associated with unique procedure-specific complications. Continuing technological improvement would favor endoscopic approaches for resection of tumors of the third ventricle in the future.

Human Midbrain Participates In Mismatch Detection Without Cognitive Activity Of The Cerebral Cortex: Case Report

Mismatch detection is the process of identification of rare stimuli from a sequence of stimuli. This important cognitive function is usually attributed to the cerebral cortex. To test the human midbrain involvement in sound mismatch detection, we recorded local field potentials in the states of deep anesthesia and clear consciousness from the drainage-electrode implanted in the cerebral aqueduct of an adult patient with an obstructive hydrocephaly who had undergone pineal region tumor removal through anterior interhemispheric transcallosal approach. We found a significant difference in the state of deep anesthesia at 256-364 ms after hearing a rarely presented sounds compared with frequently presented sounds and equally probable sounds. This difference was not found in the same experiment in the state of clear consciousness. The results suggest that human midbrain participates in mismatch detection and can do it even without cognitive activity of the cerebral cortex. Amplitude-frequency analysis of the midbrain records revealed that propofol affects the electrical activity of both human midbrain and cortex but the level of inhibition of the cortex is 6 times higher than the level of inhibition of the midbrain. We suppose that the human cortex is more susceptible to propofol than the human midbrain.

Interhemispheric transcallosal transchoroidal approach for resection of a mesencephalic lesion

A 12 years old boy presented with strabismus, left third nerve palsy (ptosis, mydriasis, downward and abducted eye), and vertical conjugate gaze paresis. A brain magnetic resonance image revealed a brainstem solid cystic tumor in the mesencephalic tegmentum, with compression of the aqueduct of Sylvius and associated supratentorial ventriculomegaly. The patient underwent an interhemispheric transcallosal transchoroidal approach for a subtotal resection of the mesencephalic periaqueductal lesion. The pathology report was a low grade neuroepithelial tumor. The patient evolved with no new neurological deficits.

Flexible Fiber CO2 Laser in Microsurgical Treatment of Intraventricular Tumors: Usefulness and Limitations

To assess usefulness and limitations of flexible fiber carbon dioxide (CO2) laser in the microsurgical treatment of intraventricular tumors. We reviewed a series of 9 patients treated with microsurgical resection of intraventricular tumors using a flexible fiber CO2 laser. The lesions involved the third ventricle (8) and the frontal horn of the right lateral ventricle (1). Histology revealed 6 craniopharyngiomas, 1 pituitary macroadenoma, 1 subependymoma, and 1 neurocytoma. In all cases, an interhemispheric transcallosal approach was performed. The laser was used during callosotomy, fornix column sectioning, tumor debulking, and to facilitate tumor dissection. We used a 5-tiered score system to assess laser's efficacy in each surgical step (approach, dissection, debulking): grade 1: laser was not at all helpful, grade 5: laser was extremely helpful. Limits of the instrument also are discussed. Gross total resection was achieved in 6 cases and subtotal resection in the remaining 3. Three patients had pulmonary complications treated without clinical sequelae. No laser-related complication was described. Mean utility score observed was 4.2 (range 3-5) during approach, 2.8 (range 2-4) during tumor dissection; and 3.3 (range 2-5) during tumor debulking. Main limits were low hemostatic effect and inefficiency versus calcified and highly vascularized tumors. The CO2 laser proved to be a useful and safe tool that could be used for intraventricular pathology; its design is suitable for narrow surgical corridors like interhemispheric fissure and foramen of Monro; its main utility is the ability to create precise and relatively bloodless cut (callosotomy, tumor debulking); low hemostatic effect is its main limit.

Microsurgical Fenestration of Thalamic Cyst Along With Third Ventriculostomy and Septal Fenestration via the Interhemispheric Transcallosal Approach: 3-Dimensional Operative Video.

Microsurgical Fenestration of Thalamic Cyst Along With Third Ventriculostomy and Septal Fenestration via the Interhemispheric Transcallosal Approach: 3-Dimensional Operative Video.

Cavum Septum Pellucidum Epidermoid- An Extremely rare occurrence

Supratentorialintraventricularepidermoids are very rare and midline septal pellucidal epidermoids are even more uncommon with only one case being reported in available literature. A 42-year-old lady with no previous complaints was admitted to the emergency services with history of intermittent headache, vomiting and giddiness of 3 months duration. A cranial computed tomography (CT) revealed a hypodense, non-enhancing intraventricular mass lesion and cranial magnetic resonance imaging (MRI) demonstrated a non-enhancing mass lesion in the septum pellucidum suggestive of an epidermoid. She underwent endoscopic-assisted surgery via an interhemispheric transcallosal approach. Intra-operatively, the lesion was located in the enlarged cavum septum pellucidum and was removed totally. An extensive literature review unearthed only 10 cases of intraventricular epidermoids and one in the septum pellucidum. We present only the second case of a midline septum pellucidum epidermoid and reflect on the paucity of supratentorial intraventricular midline epidermoids.Nepal Journal of Neuroscience 15:32-34, 2018

Multistaged, multidirectional strategy for safe removal of large meningiomas in the pineal region.

OBJECTIVE Pineal region meningiomas are rare and tend to be discovered only after they grow. Several simultaneous multidirectional approaches performed as a single operation have been proposed, but the best strategy to remove these deeply situated large meningiomas involving the deep vital venous system remains to be established. The authors advocate a multistaged, multidirectional approach to safely remove these challenging tumors. METHODS Four consecutive cases of meningioma in the pineal region were treated between April 2013 and June 2016. The 3 large (> 40 mm diameter) tumors were removed via multistaged, multidirectional approaches (2 surgeries in 2 patients and 3 surgeries in 1 patient) with gravity retraction of the occipital or parietal lobe. The large occipital skin incision extending bilaterally was used for the next operation from the contralateral side. Combinations of the occipital transtentorial approach with or without the transfalcine approach, occipital bitranstentorial/falcine approach, combined supra-/infratentorial transsinus approach, and contralateral parietal interhemispheric transcallosal approach were used. RESULTS Transient visual field deficits occurred after 2 of the 8 operations, but all tumors were removed grossly or subtotally without permanent surgery-related morbidity. The galenic venous system and straight sinus remained intact in all patients. During the follow-up period (mean 29.5 months [range 13-52 months]), there were no recurrences after the final operation. CONCLUSIONS A multistaged, multidirectional strategy with an intentional large occipital scalp incision and gravity retraction of the occipital lobe is a good choice for the safe removal of large meningiomas in the pineal region.

Gross Total Resection of Chordoid Glioma of the Third Ventricle via Anterior Interhemispheric Transcallosal Transforaminal Approach at Two Stages

Suprasellar tumors in particular tumors located in the retrochiasmatic area and anterior third ventricle are challenging cases in terms of optimal surgical exposure. Several approaches have been described including transsylvian, translamina terminalis, endoscopic endonasal, and anterior interhemispheric. Each approach has advantages and disadvantages. In this video, we present a case of retrochiasmatic anterior third ventricular tumor that was operated via anterior interhemispheric transcallosal transforaminal approach. The patient is a 42-year-old female who presented with sudden onset of severe headache and depressed level of consciousness. Computed tomography (CT) scan of the head showed a hemorrhage in the third ventricle and suprasellar cisterns. CT angiogram and magnetic resonance imaging (MRI) confirmed diagnosis of hemorrhagic mass lesion in the third ventricle. Upon further questioning of her family, we found out that she was having excessive urination and short-term memory problems for last 2 weeks. First, ventriculostomy was placed for obstructive hydrocephalus. She then underwent surgical resection via anterior interhemispheric transcallosal transforaminal approach. Foramen of Monro was enlarged by performing transchoroidal dissection. Using transforaminal route, tumor was resected. Due to the narrow surgical corridor and high vascularity of the tumor, decision was made to come back at a second stage. Using same surgical approach, in the second stage, gross total resection was performed. Postoperative MRI confirmed gross total resection. Histopathology was chordoid glioma of the third ventricle. She made excellent recovery with persistent diabetes insipidus. Currently, she is completing radiation therapy. In this video, we demonstrate techniques and pitfalls of anterior interhemispheric transcallosal approach to anterior third ventricular tumor. The link to the video can be found at: https://youtu.be/CI5c6Zup8sY .

Clinical Features, Treatment, and Long-term Outcomes of Central Neurocytoma: A 20-Year Experience at a Single Center.

Central neurocytoma (CN) is a rare central nervous system tumor the optimal management strategy of which remains controversial because of their rarity. Detailed information on CN is necessary to establish optimal management strategies. The purpose of this study was to show the clinical features, treatments, and long-term clinical outcomes of CN. A total of 63 patients with CN were surgically treated between 1995 and 2016 at West China Hospital. All pathologically proven CN cases were identified. Epidemiologic characteristics, clinical features, imaging features, functional outcomes, overall survival, and progression-free survival according to multimodal treatments were reviewed retrospectively. There were 29 males and 34 females, with a median age of 29 years (range, 15-58 years). Thirty-four patients underwent gross total resection (GTR) and 29 patients underwent subtotal resection (STR). The surgical approaches to CNs in this study included a transcortical approach (39 cases) and an interhemispheric transcallosal approach (24 cases). There were no differences in functional outcomes or initial extent of resection according to the surgical approach used. The extent of resection was GTR in 34 patients (54.0%), and STR in 29 patients (46.0%). At the median follow-up of 74 months (range, 6-205 months), the actuarial 5-year and 10-year overall survival were 93.3% and 85.4%. At the last follow-up, 8 patients had experienced tumor progression. The 5-year and 10-year progression-free rate was 73.4% and 57.5%. The initial extent of resection and multimodal treatment was not related to overall survival; however, the actuarial local control rate differed significantly according to the initial extent of resection and multimodal treatment. CN is a rare type of World Health Organization grade II primary brain tumor with a tendency to recur. Complete resection of CNs with maximal safety remains the primary treatment to minimize local progression. Adjuvant radiotherapy should be considered in patients receiving incomplete resection. The long-term clinical outcomes of CN after multimodal treatment seem to be satisfactory.

Chapter 29 - Thalamic cavernous malformations

Cavernous malformations of the thalamus represent a particularly complex subset of cavernous malformations because of the highly eloquent nature of the involved tissue and their deep location. The decision about whether to operate on any individual lesion depends on the specific location of the lesion within the thalamus, the nature of the patient's symptoms, and the patient's history. When surgery is recommended, the approach must be chosen carefully. Each part of the thalamus is reached by a different surgical approach. These approaches include the orbitozygomatic approach to the anteroinferior thalamus, the anterior interhemispheric transcallosal approach to the medial thalamus, the anterior contralateral interhemispheric transcallosal approach to the lateral thalamus, the posterior interhemispheric transcallosal approach to the posterosuperior thalamus, the parieto-occipital transventricular approach to the lateral posteroinferior thalamus, and the suboccipital supracerebellar infratentorial/transtentorial approach to the medial posteroinferior thalamus. Careful attention to safe entry zones and image guidance can allow safe removal of these lesions when necessary.

Intraventricular Tumor Resection

Neurosurgeon Marcus Czabanka treats an intraventricular tumor found in a patient with persistent headaches by resecting the tumor via an interhemispheric transcallosal approach.

The Posterior Transcallosal Approach to the Pineal Region and Posterior Third Ventricle: Intervenous and Paravenous Variants

There are a number of surgical approaches to the posterior third ventricle and pineal region, each with its associated advantages and disadvantages. To present our experience with the posterior interhemispheric transcallosal approach and to analyze the indications, technique, and outcomes. A retrospective study was conducted to identify and analyze all children and young adults who underwent the posterior transcallosal approach from July 2010 to March 2015. Perioperative data included patient demographics, signs and symptoms on presentation, tumor characteristics (type, origin, and size), complications, and clinical and radiographic outcome at final follow-up. Twenty-two patients (9 female, 13 male) were identified in 24 cases with a mean age of 10.5years (range, 3-32years). The most common tumor type was pineoblastoma (n = 6). Eleven patients underwent gross total resections; 11 underwent subtotal resections; and 2 tumors were biopsied. The intervenous operative corridor was used in 15 cases; the paravenous was used in 9. Of the 22 patients, 19 experienced 31 total postoperative events. There were 12 instances of contralateral weakness. Retraction-related hemiparesis was usually temporary; resection-related hemiparesis lasted longer. There were no complications related to occlusion of one or more bridging cortical veins or from thrombosis of 1 internal cerebral vein. Eight patients have died of tumor progression, and of the remaining 14 patients, only 1 patient to date has developed local progression. The posterior interhemispheric transcallosal approach allows resection of tumors located within the pineal region, posterior third ventricle, and thalamus. New postoperative neurological deficits can occur; however, many will improve significantly or resolve completely over time.

Combined Endoscopic and Microsurgical Interhemispheric Transcallosal Approach: A Minimally Invasive Strategy to Manage Complex Third Ventricular Lesions

Introduction: Surgical approaches to deep-seated brain pathologies, specifically lesions of the third ventricle, have always been a challenge for neurosurgeons. The endoscopic resection of intraventricular lesions has gained increasing popularity in recent years. However large, vascular, or extremely firm lesions are better approached microsurgically. In these cases, the transcallosal approach remains the most suitable option, to not violate the brain parenchyma, even if it carries a risk of postoperative cognitive and memory deficits in the event of bilateral fornical injury. In this background, the combined use of the endoscopic and microsurgical technique that requires a minimal callosotomy to reach the ventricular compartment, could combine the advantages of both techniques, then increasing the likelihood of a safe and complete resection.

Interhemispheric transcallosal transforaminal approach and its variants to colloid cyst of third ventricle: Technical issues based on a single institutional experience of 297 cases.

Context:Colloid cysts are benign intracranial lesions that usually involve the anterior third ventricle with varying appearance on imaging studies. The number of articles debating the origin of this tumor is surpassed by papers proposing the best modality available for its treatmentAim:The purpose of this study is to analyze the clinical presentation and surgical outcome of colloid cysts surgically managed over a period of thirty-two years and evaluate the technical issues based on our experience.Study Design:This is a retrospective case series study.Materials and Methods:This is a retrospective case series study on 297 consecutive patients with colloid cysts who were operated. The case records of all the patients were evaluated to record the clinical symptoms and signs, imaging findings, surgical procedure, complications and follow-up data.Results:There were 178 (60%) males and 119 (40%) females, their age ranging from 9 to 66 years with a mean age of 28 years. The mean duration of symptoms was 1.8 months. Raised intracranial pressure headache was the most common initial presenting symptom followed by visual blurring, memory disturbance and drop attacks with gait unsteadiness. The tumor was an incidental imaging finding in five patients (2%). While an interhemispheric transcallosal approach was used in 275 (92.6%) patients, it was trans-cortical in 22 (7.4%). Twenty-two patients required emergency surgery in view of worsening sensorium. Postoperative complications included memory impairment, limb weakness and seizures. Despite documented complete excision of the tumor in 6 cases, 8 patients had recurrence of tumor during follow-up.Conclusion:Colloid cysts are potential life threatening but benign lesions that can be removed safely with low morbidity and mortality through the interhemispheric transcallosal approach and its variants. The possibility for recurrence warrants, close imaging follow-up after surgery. It is essential for neurosurgeons to be familiar with the different transcallosal approaches to reach the third ventricle especially for a posteriorly situated cyst and a narrow foramen of Munro.

Keyhole approach for removal of ventricular tumors

Objective To investigate the feasibility and its technical methods of keyhole approach for removal of ventricular tumors. Methods A total of 25 patients with ventricular tumor admitted to the Department of Neurosurgery, the Second Affiliated Hospital of Soochow University from January 2010 to December 2014 were collected. The average tumor size was 38.04 cm3. All the tumors were resected via the keyhole surgical approach. The tumors of 8 patients were located in the lateral ventricles; one of them was operated via the interhemispheric transcallosal approach and 7 were operated via the cortical approach. Seven patients had the third ventricle tumor, 4 of them were resected via the interhemispheric transcallosal approach, and 2 via the supraorbital approach, and 1 via the occipital cortex. Ten patients with the fourth ventricle tumor were resected via the suboccipital midline approach. The surgical approach in 7 patients with lateral ventricle tumor and 5 with the third ventricle tumor were designed under the neuronavigation and were identified by the intraoperative navigation. Results Of the 25 patients with intraventricular tumor, 23 were totally removed and 2 were subtotally removed. Before procedure, 9 patients had obvious hydrocephalus. The hydrocephalus of 6 cases disappeared after procedure. One patient was performed ventricular puncture drainage and 1 was performed ventriclar-peritoneal drainage, and another one was performed preoperative ventricular-peritoneal drainage. One patient had residual tumor hemorrhage after procedure and was reoperated for hematoma evacuation and decompressive craniectomy. The consciousness of the patient was clear at discharge with partly aphasia and hemiparalysia. No neurologic morbidity was observed when other patients were discharged. Conclusions The position of the ventricular system is deep inside. It is suitable for using keyhole amplification effect to adequately and effectively expose surgical fields. It can effectively decrease intracranial pressure and increase surgical expose space by releasing cerebrospinal fluid through the ventricular system. Most of hydrocephalus can be subsided in patients with preoperative hydrocephalus after postoperative cerebrospinal fluid circulation smooth. There is no need for routine ventricular-peritoneal drainage. Key words: Cerebral ventricle neoplasms; Microsurgery; Keyhole approaches

ATPS-53SURGICAL THERAPY FOR CEREBRAL VENTRICLE TUMOR IN INFANTS

BACKGROUND: Surgical treatment for infant ventricle tumors is a tough procedure. We summarize the clinical information, surgical experience and perioperative therapy for 14 patients. METHODS: The patients contained 8 males, 6 females and were treated from 2010-1 to 2014-12. The age ranged from 4 to 24 months with an average of 11.5 months. We used the approach of trigone area for 3 cases, interhemispheric transcallosal for 5 cases, and sub-occipital medline for 6 cases. RESULTS: Resection extent: 10 total resection (including 2 subtotal resection), 4 partial resection. Pathology categories: 5 choroid plexus papilomas (CPP), 1 choroid plexus carcinoma,1 mature teratoma, 1 anaplastic CPP, 3 anaplastic ependymoma (WHO III), 1 ependymoma (WHO I-II ), 1 glioma, 1 medulloblastoma. PROGNOSIS: 7 cases survive (4 cases survive with different complications); 5 infants died (all died for abandoning treatment); 1 case was lost. Overall, the prognosis is poor. CONCLUSIONS: 1. Infant cerebral ventricle tumors are often large before symptoms come up. Tumor's proximity to important brain regions makes it difficult for total resection. 2. Infants have a small blood volume and poor tolerance to operation, since great blood loss usually occurs intraoperation. Time-consuming operations, such as those for total resection, require a great deal of time under anaesthesia and blood loss. It's preferable to choose a stage operation when severe blood loss occurs. 3. Acute resection is a better choice to relieve hydrocephalus rather than drainage. 4. Close contact of qualified, specialist medical staff is necessary. Intensive care and nutritional support are important for postoperation therapy.