ICG Flow 800 technology targeted STA-MCA microvascular bypass for exclusion of deep-seated fusiform MCA aneurysm: 2-dimensional operative video.

The authors present the case of an 18-year-old male with a deep-seated left fusiform dissecting M3 aneurysm for which endovascular treatment was not applicable. At the open surgery, they used the less commonly reported FLOW 800 fluorescent indocyanine green (ICG) videoangiography, before and after parental aneurysmal artery temporary clipping, to locate the distal outflow branch of the aneurysm and use it as the recipient artery for a superficial temporal artery-M4 bypass, excluding the aneurysm by clipping the parental artery. Repeated ICG FLOW 800 angiography confirmed bypass patency and adequate blood flow. The aneurysm's exclusion from circulation was confirmed by digital subtraction angiography postoperatively. The video can be found here: https://stream.cadmore.media/r10.3171/2021.10.FOCVID21183.

Cavernous Sinus Epidermoid Cyst Removal through a No-Keyhole Pterional Craniotomy: Operative Video and Technical Nuances.

Intracranial epidermoid cysts are considered benign tumors with good general prognosis. However, their radical removal may be associated with certain morbidity, especially when the capsule is attached to neurovascular structures. Epidermoid cysts located in the cavernous sinus are very rare. We present an operative video of a 22-year-old female patient, who suffered a right-sided headache for 5 years. The video demonstrates main steps and surgical nuances of resection of a right interdural cavernous sinus epidermoid cyst, measuring 22 × 19 × 21 mm (4.3 cc) ( Fig. 1A ). On initial physical examination, the patient had a right partial third nerve palsy (mild ptosis with minimal diplopia), without any other cranial nerve deficit. A right no-keyhole pterional craniotomy was performed, followed by extradural anterior clinoidectomy and peeling of the outer dural layer of the lateral wall of the cavernous sinus. The dura matter was also detached from the distal carotid dural ring, which was exposed by the clinoidectomy ( Fig. 2A ). This maneuver provided excellent exposure of the interdural epidermoid cyst, which severely compressed the oculomotor nerve against the posterior petroclinoid dural fold ( Fig. 2B ). Gross total resection of the epidermoid cyst was achieved ( Fig. 1B and C ). The patient developed a transient worsening of the third nerve palsy, which recovered completely 3 months after the surgery. Postoperative magnetic resonance imaging revealed no signs of residual tumor. The link to the video can be found at: https://youtu.be/pobhYb5ZNig .

Solid vs. cystic predominance in posterior fossa hemangioblastomas: implications for cerebrovascular risks and patient outcome.

BACKGROUND: Hemangioblastomas (HGBs) are highly vascular benign tumors, commonly located in the posterior fossa, and 80% of them are sporadic. Patients usually present with features of raised intracranial pressure and cerebellar symptoms. HGB can be classified as either mostly cystic or solids. Although the solid component is highly vascularized, aneurysm or hemorrhagic presentation is rarely described, having catastrophic results. METHODS: We identified 32 consecutive patients with posterior fossa HBG who underwent surgery from 2008 through 2020 at our medical center. Tumors were classified as predominantly cystic or solid according to radiological features. Resection was defined as gross total (GTR) or subtotal (STR). RESULTS: During the study period, 32 posterior fossa HGBs were resected. There were 26 cerebellar lesions and 4 medullar lesions, and in 2 patients, both structures were affected. Predominant cystic tumors were seen in 15 patients and solids in 17. Preoperative digital subtraction angiography (DSA) was performed in 8 patients with solid tumors, and 4 showed tumor-related aneurysms. Embolization of the tumors was performed in 6 patients, including the four tumor-related aneurysms. GTR was achieved in 29 tumors (91%), and subtotal resection in 3 (9%). Three patients had postoperative lower cranial nerve palsy. Functional status was stable in 5 patients (16%), improved in 24 (75%), and 3 patients (9%) deteriorated. One patient died 2 months after the surgery. Two tumors recurred and underwent a second surgery achieving GTR. The mean follow-up was 42.7 months (SD ± 51.0 months). CONCLUSIONS: Predominant cystic HGB is usually easily treated as the surgery is straightforward. Those with a solid predominance present a more complex challenge sharing features similar to arteriovenous malformations. Given the important vascular association of solid predominance HGB with these added risk factors, the preoperative assessment should include DSA, as in arteriovenous malformations, and endovascular intervention should be considered before surgery.

Vestibular schwannoma manifesting with hemifacial spasm in a young woman: clinical considerations and tumor removal with hearing preservation. 2-Dimensional operative video.

Hemifacial spasm (HFS) is a rare presentation of vestibular schwannoma. The authors present their experience with a 27-year-old woman who presented with normal hearing and HFS, which was the single neurological manifestation of an 18-mm vestibular schwannoma. In this challenging situation, the treatment goals were maximal tumor removal with preservation of hearing and facial nerve function and cure of the HFS. The authors achieved these goals, performing complete tumor removal via a retrosigmoid approach, assisted with neurophysiological monitoring and a 45°-angle QEVO endoscope. In the video, they explain the clinical, radiological, and surgical considerations and demonstrate the surgical technique. The video can be found here: https://stream.cadmore.media/r10.3171/2021.7.FOCVID2099.

Accuracy of freehand external ventricular drain placement in patients after a large decompressive hemicraniectomy.

Our study aim is to evaluate the accuracy of freehand external ventricular drain (EVD) placement, without the use of adjuncts to placement, immediately following a large decompressive hemicraniectomy (DC). We performed a retrospective cohort analysis comparing patients who underwent freehand EVD placement immediately after a DC, to those who underwent freehand EVD placement without DC. Computed tomography (CT) studies were used to assess accuracy based on catheter tip location. Intracranial catheter length, pre- and post-operative Evan's Index, and midline shift pre- and post-operatively were analysed as separate variables in each group. A previously described grading system was used to assess the accuracy of free hand EVD placement. There were a total 110 patients overall; DC group, n = 50; non-DC group, n = 60. There was a significant reduction from pre-operative midline shift to post-operative midline shift in the DC group (9.13 vs 6.02 mm; p = 0.0064). There was no significant difference in accuracy between the two groups (p = 0.8917), and similar rates of Grade 1 - i.e. optimal - catheter tip location (DC = 78% vs non-DC = 81%) were found. All analysed variables comparing both Grade 1 subgroups (pre- and postoperative Evan's Index, and midline shift) showed significant differences between them. Mean catheter length in Grade 1 EVD placement showed a statistically significant difference between the DC and non-DC groups (63.78 vs 59.96 mm, respectively; p = 0.009). An EVD, after DC for traumatic and non-traumatic intracranial pathologies, can be accurately placed by freehand.

Do Not Give Up on Ossified Tuberculum Sellae Meningioma - Vision Restored.

This case report accompanies a video of the treatment of a Tuberculum sellae meningioma (TSM) in a woman that presented with left eye near-blindness. The senior author conducted the operation via a pterional retractorless approach, and the patient had a full recovery. This case report discusses the unique anatomy of conchal sphenoid sinus, ossified TSM with very calcified consistency, and retractorless brain microsurgery. The resection of ossified TSM is still safe and viable with adequate microsurgical techniques and skull base instruments without compromising the neurovascular structure and with good neurological and visual outcomes for the patient.

Progressive facial numbness in a patient with multiple enhancing dural based tumours: Question.

Sarcoidosis is uncommon multiple organ granulomatous disease of unknown etiology. Neurosarcoidosis occurs in about 5% of cases and most frequently follows systemic disease. We present a case of 52 -years -old woman with a progressive hemifacial paresthesia and multiple enhancing dural based lesions. Resection of the right frontal mass allowed for the diagnosis to be made. The patient had no other features of sarcoidosis. Therefore, the diagnosis of neurosarcoidosis, especially when unaccompanied by systemic features can be challenging but should be considered in the differential diagnosis of multiple enhancing dural based tumours.

Progressive facial numbness in a patient with multiple enhancing dural based tumours: Answer.

Sarcoidosis is uncommon multiple organ granulomatous disease of unknown etiology. Neurosarcoidosis occurs in about 5% of cases and most frequently follows systemic disease. We present a case of 52-years-old woman with a progressive hemifacial paresthesia and multiple enhancing dural based lesions. Resection of the right frontal mass allowed for the diagnosis to be made. The patient had no other features of sarcoidosis. Therefore, the diagnosis of neurosarcoidosis, especially when unaccompanied by systemic features can be challenging but should be considered in the differential diagnosis of multiple enhancing dural based tumours.

Spontaneous symptomatic orbital meningoencephalocele in an adult patient. Case report and review of the literature.

Symptomatic spontaneous meningoencephalocele (MEC) is a very rare entity in adults and there have been no reported cases of spontaneous MEC through the orbital roof in an adult. We report a 41-year-old woman who presented with a left eyelid swelling for several weeks without any history of trauma. Brain magnetic resonance imaging (MRI) showed a MEC through the orbital roof causing a significant blepharocele in this young patient. Supraorbital craniotomy was performed to repair the bone defect. The symptoms resolved immediately after surgery. Even though blepharocele is a rare manifestation of spontaneous orbital MEC it should be considered in the differential diagnosis for appropriate surgical management.

The oblique occipital sinus - implications in posterior fossa approaches.

The retrosigmoid craniotomy is the standard approach to resect pathologies in the cerebellopontine angle (CPA). Following the craniotomy, the dura mater is opened in the inferolateral direction and the basal cistern arachnoid is dissected in order to release pressure by the outflow of cerebrospinal fluid (CSF) from the foramen magnum, so that the CPA compartment can be approached with minimal retraction of the cerebellum. We report two patients, both with vestibular schwannoma, in whom preoperative magnetic resonance imaging (MRI) revealed unusual large oblique occipital sinus (OOS) draining laterally into the sigmoid sinus - jugular bulb junction. The sinuses were preserved intact while dura mater was opened for CSF release. Careful preoperative imaging is essential prior to posterior fossa lesions approaches in order to evaluate the persistency of an OOS, especially in a retrosigmoid approach. Inadvertent OOS damage might result in, not only significant bleeding during dural opening, but also air embolism or venous hypertension, if the contralateral sigmoid sinus is small or absent.

A Curious Case of Crystal Deposit Disease in the Petrous Bone.

Crystal deposit disease is a rare disorder with benign dense soft tissue calcium containing accumulations presenting as pseudogout or tumoral calcinosis. It rarely affects the head and neck region and even less to the petrous bone. We describe a case of para-articular tumoral calcinosis involving the external auditory canal wall in close proximity to the temporomandibular joint with extension towards the middle cranial fossa floor in a 73-year-old man presenting with otalgia and progressing mixed hearing loss. Subtotal petrosectomy with obliteration of the middle ear and mastoid was done with complete removal of the lesion. We discuss the course, treatment and final pathology with possible explanations for the pathophysiology in this particular case. Although tumoral calcinosis is uncommon, this entity should be considered in the differential diagnosis when an osteogenic temporal lesion is seen on computed tomography or magnetic resonance imaging. The treatment for this benign tumor includes complete excision of the lesion in symptomatic cases. Proper evaluation including anamnesis of the family history and previous trauma as well as serology should be done. The exact etiology and classification of crystal deposit diseases require further study.

The infratranstentorial subtemporal approach (ITSTA): a valuable skull base approach to deep-seated non-skull base pathology.

BACKGROUND: Surgical access to space-occupying lesions such as tumors and vascular malformations located in the area of the tentorial notch, mediobasal temporal lobe, and para-midbrain is difficult. Lesions in this area are typically resected with supratentorial approaches demanding significant elevation of the temporal lobe or even partial lobectomy, or via a supracerebellar transtentorial approach. We introduce an alternative, the skull base infratranstentorial subtemporal approach (ITSTA), which provides excellent exposure of the incisural area while minimizing risk to the temporal lobe. METHODS: We included consecutive patients with pathology involving the area of the tentorial incisura, para-midbrain, and mediobasal temporal area who underwent surgery via ITSTA from 2012 to 2018. The approach includes partial mastoidectomy, temporal craniotomy, and tentorial section. Space obtained by mastoidectomy provides a sharp high-rising angle-of-attack, significantly diminishing the need for temporal lobe retraction. Surgeries were performed using microsurgical techniques, neuronavigation, and electrophysiological monitoring. Clinical presentation, tumor characteristics, extent of resection, complications, and outcome were retrospectively reviewed under a waiver of informed consent. RESULTS: Nine patients met inclusion criteria (five female, four male; mean age 44 years, range 7-72). They underwent surgery for removal of para-midbrain arteriovenous malformation (AVM, 3/9), medial tentorial meningioma (2/9), mediobasal epidermoid cyst (2/9), oculomotor schwannoma (1/9), or pleomorphic xanthoastrocytoma (PXA) of the fusiform gyrus (1/9). Three AVMs were removed completely; among six patients with tumors, gross total resection was achieved in three and subtotal resection in three. All surgeries were uneventful without complications. There were no new permanent neurological deficits. At late follow-up (mean 42.5 months), eight patients had a Glasgow Outcome Score (GOS) of 5. One 66-year-old female died 18 months after surgery for reasons not related to her disease or surgery. CONCLUSIONS: The ITSTA is a valuable skull base approach for removal of non-skull base pathologies located in the difficult tentorial-incisural parabrainstem area.

CPA Epidermoid Cyst with Rare Anatomic Variant: Anterior Inferior Cerebellar Artery Embedded in the Subarcuate Fossa: Operative Video and Technical Nuances.

Intracranial epidermoid cysts are considered benign tumors with a good general prognosis; however, their radical removal, including tumor capsule, is associated with significant morbidity, especially when the capsule is attached to neurovascular structures. We show an operative video describing main steps and surgical nuances in the resection of a large right cerebellopontine angle (CPA) epidermoid cyst in a 42-year-old male patient who presented with intractable trigeminal neuralgia. Craniectomy was performed to exposure the transverse-sigmoid sinus junction. A mold for a polymethylmethacrylate (PMMA) bone flap was built before opening the dura to avoid potentially neurotoxic effects on the cerebellum. The video illustrates the management of the rare anatomical variant of the anterior inferior cerebellar artery (AICA). Its loop was embedded in the dura, covering the subarcuate fossa where it gives off the subarcuate artery. Near total removal of the epidermoid cyst was achieved, leaving only a tiny capsule remnant adhering to the abducens nerve. Postoperatively the patient's trigeminal neuralgia was fully relieved and medications were discontinued. The patient's hearing was preserved per audiometry at the preoperative level (Gardner-Robertson II). Postoperative magnetic resonance imaging (MRI) revealed no signs of residual tumor. In this case, it was not possible to obtain optimal surgical exposure of the CPA without handling a rare anatomical anomaly of the AICA in the dura of the subarcuate fossa, which demanded coagulation and transection of the subarcuate artery and transposition of AICA with the dural cuff. This manipulation enabled optimal surgical removal of the epidermoid and didn't cause any neurological deficit. The link to the video can be found at: https://youtu.be/lLZqBHlu-uA .

Intervening in the Acute Phase of Postradiation Carotid Blowout Syndrome.

Introduction Acute carotid blowout syndrome (aCBS) is a severe complication of head and neck cancer (HNC). It can be defined as a rupture of the extracranial carotid arteries, or one of their branches, that causes life-threatening hemorrhage, and which nowadays can be treated with urgent endovascular intervention. Objective We retrospectively evaluate the endovascular management of aCBS and its outcome in years of survival. Methods Retrospectively, we describe our experience with endovascular control of aCBS in patients treated for HNC. We review the characteristics, pathology, endovascular treatment and morbidity and assess the gain in life years. Results Nine individuals were included in this study. Four patients had been previously diagnosed with laryngeal squamous cell carcinoma (SCC), one with paranasal SCC, one with nasopharyngeal carcinoma and three with oral or maxillary adenocarcinoma. All subjects underwent radiotherapy and surgical excision to different extents. Twelve endovascular procedures were performed for injuries to the internal carotid artery ( n = 3; 25%), external carotid artery ( n = 1; 7%) or one of their branches ( n = 8; 67%). Deconstructive methods were used in nine procedures, and three procedures were mainly reconstructive with deployment of covered stents. Total control of bleeding was achieved in all individuals with no intraprocedural complications. Conclusion Endovascular therapy is an effective alternative for the management of exsanguinating CBS. In our series, this palliative therapy increased the overall patient survival by an estimated 9 months.

Combination Treatment with Intravenous Tigecycline and Intraventricular and Intravenous Colistin in Postoperative Ventriculitis Caused by Multidrug-resistant Acinetobacter baumannii.

Nosocomial infections with multidrug-resistant (MDR) pathogens are a life-threatening complication in neurosurgery. An MDR Acinetobacter baumannii (A. baumannii) central nervous system (CNS) infection following neurosurgery has been previously reported and was treated with relative success using intraventricular and/or intravenous (IV) colistin, IV tigecycline, or IV colistin-rifampicin combination therapy. We present a case of MDR A. baumannii in a 13-year-old girl following parietal craniotomy for the resection of a right intraventricular meningioma. Several days after surgery, the patient presented with clinical, radiological, laboratorial, and microbiological evidence of carbapenem-resistant A. baumannii ventriculitis. She was treated with IV colistin and then with combined intraventricular-IV colistin, with partial failure. The combined treatment of IV tigecycline and associated intraventricular and intravenous colistin was started and significant improvement was seen clinically and radiologically, with negative cultures after one week. To the best of our knowledge, this is the first case of a successful combination of intraventricular and IV colistin combined with IV tigecycline after a partial treatment failure with intraventricular and IV colistin alone.

Medulla oblongata cavernoma removal through a lazy far lateral approach: operative video and technical nuances.

Removal of brainstem cavernous malformation remains a surgical challenge. We present a case of a 63-year-old female who was diagnosed with a large cavernoma located in the medulla oblongata. The patient suffered three episodes of brainstem bleeding resulting in significant neurological deficits (hemiparesis, dysphagia, and dysarthria). It was decided to remove the cavernoma through a left-sided modified far lateral approach.3 The operative video demonstrates the surgical steps and nuances of a complete removal of this complex medulla oblongata cavernous malformation. Total resection was achieved without complications. Postoperative MRI revealed no signs of residual cavernoma with clinical improvement. The video can be found here: https://youtu.be/BTtMvvLMOFM.