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Surgical management of craniopharyngioma with third ventricle involvement

Danielle de Lara, Leo F. S. Ditzel Filho, Jun Muto, Bradley A. Otto, Ricardo L. Carrau, Daniel M. Prevedello, and M.D.

Craniopharyngiomas are notorious for their ability to invade the hypothalamus and third ventricle. Although several transcranial approaches have been proposed for their treatment, the endonasal route provides direct access to the tumor with no need for cerebral retraction or manipulation of the optic apparatus. After the lesion is debulked, the unique angle of approach achieved with this technique enables the surgeon to perform an extra-capsular dissection and visualize the walls of the third ventricle, the foramina of Monro, and the anterior comissure. Moreover, the enhanced magnification and lighting afforded by the endoscope facilitate safe tumor removal, particularly in areas where there is loss of clear lesion delimitation and greater infiltration of the surrounding structures.

Herein we present the case of a 68-year-old female patient with a 3-month history of visual deterioration accompanied by worsening headaches. Investigation with magnetic resonance imaging revealed a heterogeneous mass in the suprasellar region, extending into the third ventricle and displacing the pituitary gland and stalk inferiorly. Hormonal profile was within expected range for her age. An endonasal, fully endoscopic, transplanum transtuberculum approach was performed. Gross-total removal was achieved and pathology confirmed the diagnosis of craniopharyngioma. Postoperative recovery was marked by transient diabetes insipidus. Closure was achieved with a pedicled nasoseptal flap; despite exploration of the third ventricle, there was no cerebrospinal fluid leakage. Pituitary function was preserved. Visual function has fully recovered and the patient has been uneventfully followed since surgery.

The video can be found here: http://youtu.be/it5mpofZl0Q .

Free access

Endoscopic treatment of a third ventricle choroid plexus cyst

Danielle de Lara, Leo F. S. Ditzel Filho, Jun Muto, and Daniel M. Prevedello

Choroid plexus cysts are frequent benign intraventricular lesions that infrequently cause symptoms, usually in the form of obstructive hydrocephalus. These instances are even less common in the adult population. When warranted, treatment seeks to reestablish cerebrospinal fluid flow and does not necessarily require resection of the cyst itself. Hence, endoscopic exploration of the ventricles with subsequent cyst ablation is the current treatment of choice for these lesions.

Herein we present the case of a 25-year-old female patient with a 3-week history of intermittent headaches. Investigation with computerized tomography (CT) of the head detected supratentorial hydrocephalus, with enlargement of the lateral and third ventricles. Magnetic resonance imaging revealed a homogeneous cystic lesion in the third ventricle. A right-sided, pre-coronal burr hole was carried out, followed by endoscopic exploration of the ventricular system. A third-ventriclostomy was performed. With the aid of the 30-degrees endoscope, a cyst arising from the choroid plexus was visualized along the posterior portion of the third ventricle, obstructing the aqueduct opening. The cyst was cauterized until significant reduction of its dimensions was achieved and the aqueduct opening was liberated. Postoperative recovery was without incident and resolution of the hydrocephalus was confirmed by CT imaging. The patient reports complete improvement of her headaches and has been uneventfully followed since surgery.

The video can be found here: http://youtu.be/XBtj_SqY07Q .

Full access

Letter to the Editor. Endoscopic transpterygoid corridor

Jun Muto, Daniel M. Prevedello, and Ricardo L. Carrau

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Retrosigmoid approach for resection of petrous apex meningioma

Daniel G. de Souza, Leo F. S. Ditzel Filho, Girma Makonnen, Matteo Zoli, Cristian Naudy, Jun Muto, and Daniel M. Prevedello

We present the case of a 50-year-old female with a 1-year history of right-side facial numbness, as well as an electric shock-like sensation on the right-side of the face and tongue. She was previously diagnosed with vertigo and trigeminal neuralgia. MRI was obtained showing a large right cerebellopontine angle mass. A retrosigmoid approach was performed and total removal was achieved after dissection of tumor from brainstem and cranial nerves IV, V, VI, VII and VIII. Pathology confirmed the diagnosis of a meningioma (WHO Grade I). The patient was discharged neurologically intact on the third postoperative day free of complications.

The video can be found here: http://youtu.be/-tR0FtMiUDg.

Free access

Intraoperative real-time near-infrared optical imaging for the identification of metastatic brain tumors via microscope and exoscope

Jun Muto, Yutaka Mine, Yu Nakagawa, Masahiro Joko, Hiroshi Kagami, Makoto Inaba, Mitsuhiro Hasegawa, John Y. K. Lee, and Yuichi Hirose

OBJECTIVE

As chemotherapy and radiotherapy have developed, the role of a neurosurgeon in the treatment of metastatic brain tumors is gradually changing. Real-time intraoperative visualization of brain tumors by near-infrared spectroscopy (NIRS) is feasible. The authors aimed to perform real-time intraoperative visualization of the metastatic tumor in brain surgery using second-window indocyanine green (SWIG) with microscope and exoscope systems.

METHODS

Ten patients with intraparenchymal brain metastatic tumors were administered 5 mg/kg indocyanine green (ICG) 1 day before the surgery. In some patients, a microscope was used to help identify the metastases, whereas in the others, an exoscope was used.

RESULTS

NIRS with the exoscope and microscope revealed the tumor location from the brain surface and the tumor itself in all 10 patients. The NIR signal could be detected though the normal brain parenchyma up to 20 mm. While the mean signal-to-background ratio (SBR) from the brain surface was 1.82 ± 1.30, it was 3.35 ± 1.76 from the tumor. The SBR of the tumor (p = 0.030) and the ratio of Gd-enhanced T1 tumor signal to normal brain (T1BR) (p = 0.0040) were significantly correlated with the tumor diameter. The SBR of the tumor was also correlated with the T1BR (p = 0.0020). The tumor was completely removed in 9 of the 10 patients, as confirmed by postoperative Gd-enhanced MRI. This was concomitant with the absence of NIR fluorescence at the end of surgery.

CONCLUSIONS

SWIG reveals the metastatic tumor location from the brain surface with both the microscope and exoscope systems. The Gd-enhanced T1 tumor signal may predict the NIR signal of the metastatic tumor, thus facilitating tumor resection.

Open access

Utility of intraoperative real-time near-infrared fluorescence surgery for spinal schwannoma

Jun Muto, Yutaka Mine, Sota Nagai, Naoyuki Shizu, Hiroki Takeda, Daiki Ikeda, Akifumi Saito, Masahiro Joko, Mitsuhiro Hasegawa, Shinjiro Kaneko, Tatsushi Inoue, John Y. K. Lee, and Yuichi Hirose

The authors report the first cases of fluorescence-guided spinal surgery of schwannomas using near-infrared fluorescence imaging with the delayed window indocyanine (ICG) green (DWIG) technique for accurate real-time intraoperative tumor visualization.

Patients with intradural spinal schwannomas received 0.5 mg/kg ICG at the beginning of surgery. After 1 hour, using the DWIG technique, near-infrared spectroscopy (NIRS) detected the spinal schwannomas, showing the exact tumor location and boundaries. DWIG with NIRS microscopy confirmed the exact location of spinal schwannomas before and after opening of the dura mater, thereby facilitating successful tumor dissection from the surrounding tissues, tumor resection, and confirmation of tumor removal.

The video can be found here: https://stream.cadmore.media/r10.3171/2021.10.FOCVID21158

Free access

Anatomic comparison of the endonasal and transpetrosal approaches for interpeduncular fossa access

Kenichi Oyama, Ph.D., Daniel M. Prevedello, Leo F. S. Ditzel Filho, Jun Muto, Ph.D., Ramazan Gun, Edward E. Kerr, Bradley A. Otto, and Ricardo L. Carrau

Object

The interpeduncular cistern, including the retrochiasmatic area, is one of the most challenging regions to approach surgically. Various conventional approaches to this region have been described; however, only the endoscopic endonasal approach via the dorsum sellae and the transpetrosal approach provide ideal exposure with a caudal-cranial view. The authors compared these 2 approaches to clarify their limitations and intrinsic advantages for access to the interpeduncular cistern

Methods

Four fresh cadaver heads were studied. An endoscopic endonasal approach via the dorsum sellae with pituitary transposition was performed to expose the interpeduncular cistern. A transpetrosal approach was performed bilaterally, combining a retrolabyrinthine presigmoid and a subtemporal transtentorium approach. Water balloons were used to simulate space-occupying lesions. “Water balloon tumors” (WBTs), inflated to 2 different volumes (0.5 and 1.0 ml), were placed in the interpeduncular cistern to compare visualization using the 2 approaches. The distances between cranial nerve (CN) III and the posterior communicating artery (PCoA) and between CN III and the edge of the tentorium were measured through a transpetrosal approach to determine the width of surgical corridors using 0- to 6-ml WBTs in the interpeduncular cistern (n = 8).

Results

Both approaches provided adequate exposure of the interpeduncular cistern. The endoscopic endonasal approach yielded a good visualization of both CN III and the PCoA when a WBT was in the interpeduncular cistern. Visualization of the contralateral anatomical structures was impaired in the transpetrosal approach. The surgical corridor to the interpeduncular cistern via the transpetrosal approach was narrow when the WBT volume was small, but its width increased as the WBT volume increased. There was a statistically significant increase in the maximum distance between CN III and the PCoA (p = 0.047) and between CN III and the tentorium (p = 0.029) when the WBT volume was 6 ml.

Conclusions

Both approaches are valid surgical options for retrochiasmatic lesions such as craniopharyngiomas. The endoscopic endonasal approach via the dorsum sellae provides a direct and wide exposure of the interpeduncular cistern with negligible neurovascular manipulation. The transpetrosal approach also allows direct access to the interpeduncular cistern without pituitary manipulation; however, the surgical corridor is narrow due to the surrounding neurovascular structures and affords poor contralateral visibility. Conversely, in the presence of large or giant tumors in the interpeduncular cistern, which widen the spaces between neurovascular structures, the transpetrosal approach becomes a superior route, whereas the endoscopic endonasal approach may provide limited freedom of movement in the lateral extension.

Restricted access

Comparative analysis of the anterior transpetrosal approach with the endoscopic endonasal approach to the petroclival region

Jun Muto, Daniel M. Prevedello, Leo F. S. Ditzel Filho, Ing Ping Tang, Kenichi Oyama, Edward E. Kerr, Bradley A. Otto, Takeshi Kawase, Kazunari Yoshida, and Ricardo L. Carrau

OBJECTIVE

The endoscopic endonasal approach (EEA) offers direct access to midline skull base lesions, and the anterior transpetrosal approach (ATPA) stands out as a method for granting entry into the upper and middle clival areas. This study evaluated the feasibility of performing EEA for tumors located in the petroclival region in comparison with ATPA.

METHODS

On 8 embalmed cadaver heads, EEA to the petroclival region was performed utilizing a 4-mm endoscope with either 0° or 30° lenses, and an ATPA was performed under microscopic visualization. A comparison was executed based on measurements of 5 heads (10 sides). Case illustrations were utilized to demonstrate the advantages and disadvantages of EEA and ATPA when dealing with petroclival conditions.

RESULTS

Extradurally, EEA allows direct access to the medial petrous apex, which is limited by the petrous and paraclival internal carotid artery (ICA) segments laterally. The ATPA offers direct access to the petrous apex, which is blocked by the petrous ICA and abducens nerve inferiorly. Intradurally, the EEA allows a direct view of the areas medial to the cisternal segment of cranial nerve VI with limited lateral exposure. ATPA offers excellent access to the cistern between cranial nerves III and VIII. The quantitative analysis demonstrated that the EEA corridor could be expanded laterally with an angled drill up to 1.8 times wider than the bone window between both paraclival ICA segments.

CONCLUSIONS

The midline, horizontal line of the petrous ICA segment, paraclival ICA segment, and the abducens nerve are the main landmarks used to decide which approach to the petroclival region to select. The EEA is superior to the ATPA for accessing lesions medial or caudal to the abducens nerve, such as chordomas, chondrosarcomas, and midclival meningiomas. The ATPA is superior to lesions located posterior and/or lateral to the paraclival ICA segment and lesions with extension to the middle fossa and/or infratemporal fossa. The EEA and ATPA are complementary and can be used independently or in combination with each other in order to approach complex petroclival lesions.

Free access

Letters to the Editor: Craniopharyngioma adherence to the hypothalamus

José M. Pascual, Ruth Prieto, Rodrigo Carrasco, Inés Castro-Dufourny, and Laura Barrios

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Shorter survival time of adolescents and young adult patients than older adults with spinal cord glioblastoma: a multicenter study

Tomoo Inoue, Toshiki Endo, Jun Muto, Daisuke Umebayashi, Takafumi Mitsuhara, Seiji Shigekawa, Ryo Kanematsu, Motoyuki Iwasaki, Toshihiro Takami, Kazutoshi Hida, Masaki Mizuno, and Investigators of Intramedullary Spinal Cord Tumors in the Neurospinal Society of Japan

OBJECTIVE

Cancers in adolescents and young adults (AYAs) (age 15–39 years) often present with unique characteristics and poor outcomes. To date, spinal cord glioblastoma, a rare tumor, remains poorly understood across all age groups, including AYAs. This comparative study aimed to investigate the clinical characteristics and outcomes of spinal cord glioblastoma in AYAs and older adults (age 40–74 years), given the limited availability of studies focusing on AYAs.

METHODS

Data from the Neurospinal Society of Japan’s retrospective intramedullary tumor registry (2009–2020) were analyzed. Patients were dichotomized on the basis of age into AYAs and older adults. Univariate and multivariate Cox proportional hazards regression models were utilized to explore risk factors for overall survival (OS).

RESULTS

A total of 32 patients were included in the study, with a median (range) age of 43 (15–74) years. Of these, 14 (43.8%) were AYAs and 18 (56.2%) were older adults. The median OS was 11.0 months in AYAs and 32.0 months in older adults, and the 1-year OS rates were 42.9% and 66.7%, respectively, with AYAs having a significantly worse prognosis (p = 0.017). AYAs had worse preoperative Karnofsky Performance Status (KPS) than older patients (p = 0.037). Furthermore, AYAs had larger intramedullary tumors on admission (p = 0.027) and a significantly higher frequency of intracranial dissemination during the clinical course (p = 0.048). However, there were no significant differences in the degrees of surgical removal or postoperative radiochemotherapy between groups. The Cox proportional hazards regression model showed that AYAs (HR 3.53, 95% CI 1.17–10.64), intracranial dissemination (HR 4.30, 95% CI 1.29–14.36), and no radiation therapy (HR 57.34, 95% CI 6.73–488.39) were risk factors for mortality for patients of all ages. Worse preoperative KPS did not predict mortality in AYAs but did in older adults. The high incidence of intracranial dissemination may play an important role in the poor prognosis of AYAs, but further studies are needed.

CONCLUSIONS

The clinical characteristics of AYAs with spinal cord glioblastoma differ from those of older adults. The prognosis of AYAs was clearly worse than that of older adults. The devastating clinical course of spinal glioblastoma in AYAs was in line with those of other cancers in this age group.