Augmented reality simulation as training model of ventricular puncture: Evidence in the improvement of the quality of punctures.

BACKGROUND: Ventricular puncture is a common procedure in neurosurgery and the first that resident must learn. Ongoing education is critical to improving patient outcomes. However, training at the expense of potential risk to patients warrants new and safer training methods for residents. METHODS: An augmented reality (AR) simulator for the practice of ventricular punctures was designed. It consists of a navigation system with a virtual 3D projection of the anatomy over a 3D-printed patient model. Forty-eight participants from neurosurgery staff performed two free-hand ventricular punctures before and after a training session. RESULTS: Participants achieved enhanced accuracy in reaching the target at the Monro foramen after practicing with the system. Additional metrics revealed significantly better trajectories after the training. CONCLUSION: The study confirms the feasibility of AR as a training tool. This motivates future work towards standardising new educative methodologies in neurosurgery.

Neurenteric Cyst of the Posterior Cranial Fossa: A Case Report and Literature Review.

Neurenteric cysts (NCs) are rare benign endodermal lesions of the central nervous system (CNS), most commonly found in the spinal cord. Intracranial lesions are rare, among which the posterior fossa appears to be the predominant location. We present a case of a 60-year-old man who presented with a suddenly decreased level of consciousness. After a series of radiological studies were done, a multilobulated cystic lesion in the right posterior fossa was observed. Surgical resection was performed and based on its histopathological characteristics, NC diagnosis was confirmed. Because of the wide list of differential diagnoses and low specificity of radiological features, surgical gross total resection remains the most effective treatment, followed by diagnosis confirmation through histopathological techniques.

Upward transtentorial herniation: A new role for endoscopic third ventriculostomy.

BACKGROUND: The placement of external ventricular drainage (EVD) to treat hydrocephalus secondary to a cerebellar stroke is controversial because it has been associated to upward transtentorial herniation (UTH). This case illustrates the effectiveness of endoscopic third ventriculostomy (ETV) after the ascending herniation has occurred. CASE DESCRIPTION: A 50-year-old man had a cerebellar stroke with hemorrhagic transformation, tonsillar herniation, and non-communicating obstructive hydrocephalus. Considering that the patient was anticoagulated and thrombocytopenic, an EVD was placed initially, followed by clinical deterioration and UTH. We performed a suboccipital craniectomy immediately after clinical worsening, but the patient did not show clinical or radiological improvement. On the 5th day, we did an ETV, which reverses the upward herniation and hydrocephalus. The patient improved progressively with good neurological recovery. CONCLUSION: ETV is an effective and safe procedure for obstructive hydrocephalus. The successful resolution of the patient's upward herniation after the ETV offers a potential option to treat UTH and advocates further research in this area.

Frontotemporal brain sagging syndrome: Craniospinal hypovolemia secondary to a T6-T7 cerebrospinal fluid-venous fistula.

BACKGROUND: The frontotemporal brain sagging syndrome (FTBSS) is defined as an insidious/progressive decline in behavior and executive functions, hypersomnolence, and orthostatic headaches attributed to cerebrospinal fluid (CSF) hypovolemia. Here, a T6 CSF-venous fistula (e.g., between the subarachnoid CSF and a paraspinal vein) resulted in a CSF leak responsible for craniospinal hypovolemia. CASE DESCRIPTION: A 56-year-old male started with orthostatic headaches and fatigue after scuba diving. His symptoms included progressive, vertigo, tinnitus, nausea, lack of judgment, inappropriate behavior, memory dysfunction, apathy, tremor, orofacial dyskinesia, dysarthria, dysphagia, and hypersomnolence. The lumbar puncture revealed an opening pressure of 0 cm H2O. Magnetic resonance imaging (MRI) findings included brain sagging, bilateral temporal lobe herniation, and pachymeningeal enhancement. The computed tomography (CT) myelogram showed a thoracic diverticulum and a CSF-venous leak at the T6-T7 level. Surgery, which comprised a T6-T7 laminotomy, allowed for dissecting, clipping, and ligating the diverticulum/fistula. The patient improved postoperatively (e.g., cognitive, behavioral, and brainstem symptoms). The follow-up MRI's showed the reversion of the sagging index/uncal herniation. CONCLUSION: The FTBSS should be considered in the differential diagnosis of an early onset frontotemporal dementia. Establishing the diagnosis and localizing the site of a spinal CSF/venous leak warrant both MRI and myelogram CT studies, to pinpoint the CSF leak site for proper surgical clipping/ligation of these thoracic diverticulum/CSF-venous leaks.

Hybrid fluorescein-guided surgery for pituitary adenoma resection: a pilot study.

OBJECTIVE: The authors conducted a pilot study on hybrid fluorescein-guided surgery for pituitary adenoma resection and herein describe the feasibility and safety of this technique. METHODS: In this pilot study, the authors included all consecutive patients presenting with pituitary adenomas, functioning and nonfunctioning. They performed a hybrid fluorescein-guided surgical technique for tumor resection. An endonasal endoscopic approach was used; after exposure of the rostrum of the sphenoid sinus, they administered a bolus of 8 mg/kg of fluorescein sodium (FNa) intravenously, and during resection, they alternated between endoscopic and microscopic techniques to guide the resection under a YELLOW 560 filter. RESULTS: The study included 15 patients, 7 men (47%) and 8 women (53%). Of the pituitary adenomas, 7 (46%) were nonfunctioning, 6 (40%) were GH secreting, 1 (7%) was prolactin secreting, and 1 (7%) was ACTH secreting. There were no FNa-related complications (anaphylactic reactions); yellowish staining of urine, skin, and mucosa was seen in all patients and resolved in a maximum time of 24 hours. After color spectrophotometric analysis, the authors identified a statistical difference in fluorescence among tumor, gland, and scar tissue (p = 0.01). CONCLUSIONS: This is the first study of its kind to describe the feasibility and safety of using FNa to guide the resection of pituitary adenomas. The authors found this technique to be safe and feasible. It may be used to obtain better surgical results, especially for hormone-producing and recurring tumors, as well as for reducing the learning curve in pituitary adenoma surgery.

Neurosurgical Therapy for Status Epilepticus in Oligoastrocytoma Patients.

BACKGROUND: Super-refractory status epilepticus (SRSE) is a life-threatening neurologic emergency defined as "status epilepticus (SE) that continues 24 hours or more after the onset of anesthesia, including those cases in which the SE recurs on the reduction or withdrawal of anesthesia," which occurs in 10% to 15% of patients with SE and rarely has been resolved surgically. CASE DESCRIPTIONS: A 20-year-old man with SRSE and a long history of left parieto-occipital oligoastrocytoma was admitted for convulsive SE that became SRSE and underwent lesionectomy guided by electrocorticography and neuronavigation for local tumor recurrence. Histopathologic diagnosis was oligoastrocytoma. SRSE was aborted and the patient recovered fully without any functional deficits. CONCLUSIONS: The lesionectomy guided by electrocorticography and neuronavigation should be considered as a treatment option for patients with SRSE.

Endoscopic endonasal infrasellar approach to the sellar and suprasellar regions: technical note.

We report a technical variation of the endoscopic endonasal approach to the sellar and suprasellar regions which relies on the use of a 45-degree angled endoscope. The so-called "infrasellar approach" aims at excising lesions situated within the intermediate and posterior lobes of the pituitary gland without damaging the anterior lobe, thus potentially minimizing endocrinological morbidity. In this regard the endoscopic infrasellar approach might be advantageous in selected cases when compared with the traditional transsphenoidal approach with the microscope. We describe the technique and illustrate it with representative clinical cases.