Expanded endoscopic endonasal approach for the resection of midline craniopharyngiomas with hypothalamic involvement.

BACKGROUND: With relevant surrounding neurological structures and potential involvement of the hypothalamus, the surgical management of craniopharyngiomas is complex. Compared to the transcranial approach, the expanded endoscopic endonasal approach provides direct access to the supradiaphragmatic and retrochiasmatic areas without crossing nerves and arteries. METHOD: Based on our substantial experience of 68 patients operated on between 2008 and 2022 by endoscopic surgery, our strategy has evolved such that all of our midline infundibular craniopharyngiomas with hypothalamic involvement are currently treated with an expanded endonasal route, except for tumours isolated to the third ventricle. Vascularized mucosal nasoseptal flaps are required for closure. Fine details of the related anatomy and surgical technique are described. CONCLUSION: Expanded endoscopic endonasal approach is a safe and effective route for resection of midline suprasellar craniopharyngiomas with hypothalamic involvement in centres of expertise.

Return to the Original Work Activity Following the Full-endoscopic Lumbar Surgery under the Local Anesthesia.

Transforaminal full-endoscopic spine (TF-FES) surgery is minimally invasive and can be performed under local anesthesia. Thus, it is expected that the patient can return to work (RTW) quickly. However, information in the literature regarding this is sparse. The purpose of this study is to review the timing of RTW after TF-FES surgery. This study involved 50 patients (14 women, 36 men; mean age 44.5 years, age range: 20-65 years) who underwent TF-FES surgery between January 2016 and April 2018. All the patients were active workers. Occupations varied widely (e.g., physician, nurse, helper, clerk, construction worker, chef, and schoolteacher). There were no surgery-related complications. Median time to RTW was 21 days. More than half of the patients could RTW within 21 days. In all, 12 cases (24%) could have RTW within 7 days. Occupations of 12 patients who achieved RTW within 7 days included physician, company owner, and restaurant owner, with 11 in the Light work, 1 was in the Medium work, and none in the Heavy work. All 12 had a quick RTW because their work was Light and they could not take prolonged sick leave. Prompt RTW is possible with TF-FES surgery. The biggest merit of TF-FES surgery is minimal invasiveness to the muscles of the back. Also, it can be performed under local anesthesia. Our findings reveal quicker RTW after surgery, depending on occupational type.

Quality of life and olfactory function after suprasellar craniopharyngioma surgery-a single-center experience comparing transcranial and endoscopic endonasal approaches.

The endoscopic endonasal approach to suprasellar craniopharyngiomas has become popular as alternative to transcranial approaches. However, the literature lacks data regarding quality of life and olfactory function. The assessment of the long-term quality of life and olfactory function of all patients harboring a suprasellar craniopharyngioma who underwent surgery in our department has been done. Patient characteristics and perioperative data were gathered in a prospectively maintained database. At the last follow-up visit, the olfactory function and the quality of life (ASBQ, SNOT-22) as well as visual and pituitary function were assessed. Thirteen and 17 patients underwent surgery via a transcranial (T) and endonasal (E) route, respectively. No differences were seen in ASBQ, SNOT-22, and olfactory function between T and E, but in E were more full-time worker and less obesity. CSF leaks occurred in 15% of T and 29% of E (p = 0.43). Patients from group E had a superior visual outcome which was most pronounced in the visual field. The degree of new anterior and posterior pituitary gland deficiency after surgery and in the follow-up was lower in group E. The general and sinonasal quality of life and the olfactory function are equal in E and T. E is associated with a superior visual outcome, lower rates of diabetes insipidus, and lower rates of obesity, but has a higher risk for postoperative CSF leaks.

Surgical treatment of hypothalamic hamartomas.

Hypothalamic hamartomas are aberrant masses, composed of abnormally distributed neurons and glia. Along endocrine and cognitive symptoms, they may cause epileptic seizures, including the specific gelastic and dacrystic seizures. Surgery is the treatment of drug-resistant hamartoma epilepsy, with associated positive results on endocrine, psychiatric, and cognitive symptoms. Recently, alternatives to open microsurgical treatment have been proposed. We review these techniques and compare their efficacy and safety. Open resection or disconnection of the hamartoma, either through pterional, transcallosal, or transventricular approach, leads to good epileptological control, but its high complication rate, up to 30%, limits its indications. The purely cisternal peduncular forms remain the only indication of open, pterional approach, while other strategies have been developed to overcome the neurological, endocrine, behavioral, or cognitive complications. Laser and radiofrequency thermocoagulation-based disconnection through robot-guided stereo-endoscopy has been proposed as an alternative to open microsurgical resection and stereotactic destruction. The goal is to allow safe and complete disconnection of a possibly complex attachment zone, through a single intraparenchymal trajectory which allows multiple laser or radiofrequency probe trajectory inside the ventricle. The efficacy was high, with 78% of favorable outcome, and the overall complication rate was 8%. It was especially effective in patients with isolated gelastic seizures and pure intraventricular hamartomas. Stereotactic radiosurgery has proved as efficacious and safer than open microsurgery, with around 60% of seizure control and a very low complication rate. Multiple stereotactic thermocoagulation showed very interesting results with 71% of seizure freedom and 2% of permanent complications. Stereotactic laser interstitial thermotherapy (LiTT) seems as effective as open microsurgery (from 76 to 81% of seizure freedom) but causes up to 20% of permanent complications. This technique has however been highly improved by targeting only the epileptogenic onset zone in the hamartoma, as shown on preoperative functional MRI, leading to an improvement of epilepsy control by 45% (92% of seizure freedom) with no postoperative morbidity. All these results suggest that the impact of the surgical procedure does not depend on purely technical matters (laser vs radiofrequency thermocoagulation or stereotactic vs robot-guided stereo-endoscopy) but relies on the understanding of the epileptic network, including inside the hamartoma, the aim being to plan an effective disconnection or lesion of the epileptogenic part while sparing the adjacent functional structures.

An unusual case of post-nasal "clicking" after pituitary surgery.

We report a case of a 64-year-old female who represented two months after pituitary surgery with the novel complication of intermittent disabling post-nasal pulsatile "clicking". Imaging and endoscopic examination showed a residual sella cleft with the tumour capsule and diaphragma cupping against the anterior sella bony defect with each pulsation, causing the clicking. The clicking resolved following second redo surgical endoscopic repair to jail a fat graft within the residual cleft with a central barricade of conchal cartilage graft and onlay standard repair.

Percutaneous Endoscopic Thoracic Decompression for Thoracic Spinal Stenosis Under Local Anesthesia.

BACKGROUND: Thoracic spinal stenosis (TSS), a common vertebral degenerative disease, is generally treated via surgical decompression. Percutaneous endoscopic thoracic decompression (PETD) under local anesthesia is considered a relatively safe, minimally invasive procedure. Few reports detail the success of endoscopic decompression for treatment of TSS caused by ossification of ligamentum flavum, the most common cause of TSS. This study investigated application of PETD for treatment of TSS caused by ossification of ligamentum flavum, ossification of posterior longitudinal ligament, or thoracic disc herniation. METHODS: From January 2017 to January 2019, 12 consecutive patients (6 men and 6 women) underwent PETD. TSS was caused by ossification of ligamentum flavum in 5 patients, thoracic disc herniation in 5 patients, and ossification of posterior longitudinal ligament in 2 patients. All cases were followed up for 1 year postoperatively. Preoperative and postoperative neurologic status was evaluated using the modified Japanese Orthopaedic Association score, and complications were documented. RESULTS: Average modified Japanese Orthopaedic Association score improved significantly from 6.25 ± 1.60 preoperatively to 9.75 ± 1.21 at final follow-up. Dural tear was observed in 1 case during the intervention, and 1 case had transient worsening of preoperative paralysis. Recovery at final follow-up was classified as excellent in 5 cases, good in 6 cases, and poor in 1 case. CONCLUSIONS: This retrospective analysis showed that PETD under local anesthesia may be a feasible alternative to treat TSS in elderly patients with other underlying complications for whom general anesthesia or major surgical trauma would be harmful.

Stepwise Local Anesthesia for Percutaneous Endoscopic Interlaminar Discectomy: Technique Strategy and Clinical Outcomes.

BACKGROUND: Due to suboptimal pain control under conventional local anesthesia, percutaneous endoscopic interlaminar discectomy is typically performed under general anesthesia. The purpose of this study was to develop a stepwise approach of local anesthesia for endoscopic interlaminar discectomy and evaluate its efficacy. METHODS: A stepwise local anesthesia was developed, which mainly includes 3 steps: conventional local anesthesia from skin to laminae, epidural injection, and nerve root block. From June 2015 to May 2017, consecutive patients who underwent endoscopic interlaminar discectomy were included. Local anesthesia or general anesthesia was used based on patients' preference. Anesthetic effectiveness was evaluated as excellent, good, or poor, and adverse events were recorded. Hospitalization expense was compared between the 2 groups. Clinical outcomes were assessed using the Visual Analog Scale and the Oswestry Disability Index. RESULTS: There were 98 patients included in the study. Among them, 48 received stepwise local anesthesia and the other 50 received general anesthesia. In the stepwise local anesthesia group, 40 (83.3%) patients rated anesthetic effectiveness as excellent, 7 (14.6%) as good, and 1 (2.1%) as poor. Nine patients had complications that may be associated with local anesthesia, including dyspnea, temporary paresis of legs, and temporary worsened dysesthesia or numbness in legs. After surgery, the patients' leg pain and Oswestry Disability Index significantly improved in both groups. On average, hospitalization expense was approximately 20% less when local anesthesia was used, as compared with using general anesthesia. CONCLUSIONS: The stepwise local anesthesia can achieve satisfactory pain control and seems to be a good choice for endoscopic interlaminar discectomy.

MR Navigation and Tractography-Assisted Transcranial Neuroendoscopic Aspiration of Pediatric Thalamic Abscess.

AIM: Management of thalamic abscess is being considered as a contentious issue in neurosurgery. Regarding these lesions, besides removing the abscess, the most minimal morbidity is targeted during surgery and planning. MATERIAL AND METHOD: A 5-year-old female presented with the symptoms of altered consciousness and left hemiparesis. Her medical history pointed out that she was being followed up for a congenital cardiac anomaly consisting of transposition of the great arteries and a ventricular septal defect. A cranial MRI revealed 2 masses with peripheral contrast enhancement in the right frontal and thalamic regions. She was operated immediately and the right frontal mass, compatible with abscess, was totally excised with frontal mini craniotomy. The patient was hospitalized and followed up under intensive parenteral antibiotics. Control cranial imaging revealed progression in the size of the thalamic abscess, which was corroborative with the increased left hemiparesis. MR tractography was obtained and the patient underwent MR navigation and tractography combined neuronavigation-assisted transcranial neuroendoscopic aspiration of the thalamic abscess. RESULTS: The patient was stable in the early and late postoperative periods and her hemiparesis showed a dramatic recovery with no additional neurological deficits. CONCLUSION: Neuronavigation is considered as one of the techniques that aid the neurosurgeon to augment the success of surgery and minimize the morbidity, especially in critically localized lesions, i.e., eloquent areas. Combining MR navigation with MR tractography images and using them during neuronavigation to assist endoscopic procedures may decrease the surgical morbidity as much as possible.

Preservation of Hypothalamic Function with Endoscopic Endonasal Resection of Hypothalamus-Invaded Craniopharyngiomas.

OBJECTIVE: To analyze the preservation of hypothalamic function using the endoscopic endonasal approach (EEA) in a single-center clinical series of patients with hypothalamus-invaded craniopharyngioma (CP) and compare this series with reported cases by the open transcranial approach (TCA). METHODS: A retrospective review of hypothalamus-invaded CP surgical cases treated with EEA was performed. Hypothalamic damage was evaluated in terms of the body mass index (BMI), endocrine status, and quality of life before and after surgery. A review of the available literature reporting the use of EEA and TCA over the last decade was performed for comparison. RESULTS: In total, 63 cases amenable to EEA were investigated. The elevation in BMI was substantial and an increase in BMI greater than 9% was observed in 22 patients (34.92%). Most patients exhibited a BMI gain >9% within 3 months postoperatively. A total of 16 of the 19 patients who had normal anterior pituitary function preoperatively worsened after surgery. Of the 27 cases reporting preoperative partial hypopituitarism, 16 cases worsened postoperatively and 11 cases remained unchanged. All 9 cases with preoperative panhypopituitarism remained unchanged postoperatively. A total of 40 new cases developed diabetes insipidus, and 3 of the 10 patients with preoperative diabetes insipidus exhibited resolved at the latest follow-up. The quality of life showed no significant difference. CONCLUSIONS: EEA can achieve greater gross total resection than TCA when performed by an experienced surgeon. Combined with the reduced postoperative hypothalamic damage in our patients with only hypothalamus-invaded CP, especially the shortened time horizons of hypothalamic obesity development and reduced percentage of patients with obesity, the EEA technique should be a preferred alternative over TCA.

Endoscopic management of benign cystic lesions of the thalamus with fenestrated stent placement.

Benign intracranial cystic lesions of the thalamus are an uncommon clinical entity rarely requiring operative decompression. In combination with cyst fenestration, cerebrospinal fluid (CSF) flow diversion or fenestrated stent placement may be performed at the time of surgery. We describe a method of treatment of these cysts using endoscopic cyst fenestration with fenestrated transventricular stent placement. Three patients with benign cystic lesions were treated with stereotactic-guided, endoscopic fenestration and fenestrated stent placement. All 3 had radiographic and clinical improvement. There were no complications. Endoscopic fenestration and transventricular fenestrated stent placement is a minimally invasive, effective, and safe method to decompress benign, symptomatic cystic lesions of the thalamus.

Pediatric pituitary adenomas.

BACKGROUND: Pediatric pituitary adenomas are a rare medical entity that makes up a small portion of intracranial tumors in children and adolescents. Although benign, the majority of these lesions are secreting functional tumors with the potential for physiological sequela that can profoundly affect a child's development. FOCUS OF REVIEW: In this review, we discuss the medical and surgical management of these tumors with a focus on clinical presentation, diagnostic identification, surgical approach, and associated adjuvant therapies. We will also discuss our current treatment paradigm using endoscopic, open, and combined approaches to treat these tumors. The management of pituitary tumors requires a multidisciplinary team of surgeons, endocrinologists, and neuroanesthesiologists as well as neurocritical care specialists to deliver comprehensive care.

Is Gross Total Resection Reasonable in Adults with Craniopharyngiomas with Hypothalamic Involvement?

OBJECTIVE: The treatment of hypothalamus-invading craniopharyngiomas, based on pediatric experience, is subtotal resection (STR) with radiotherapy. This strategy sometimes leads to uncontrollable tumor progression. In adults, with the use of endoscopic endonasal surgery (EES), does removing the hypothalamic part of the tumor-whenever possible-compromise the outcome of the patients? METHODS: We included adults with craniopharyngioma treated by a first EES in 2008-2016 by senior neurosurgeon (E.J.). Endocrine, ophthalmologic, and hypothalamic data were retrospectively collected, including body mass index (BMI), cognitive and social status, with a systematic follow-up interview. Magnetic resonance imaging scans were graded according to Puget classification: 0, no hypothalamic involvement; 1, hypothalamic displacement; and 2, hypothalamic involvement. Grade 2 tumors were separated into gross total resection (GTR) or STR. RESULTS: We included 22 patients aged 18-79 years. Presenting symptoms were visual (14, 64%), endocrine dysfunction (10, 45%), BMI >30 (8, 36%), and cognitive/psychiatric impairment (9, 41%). Fourteen (64%) were grade 2 craniopharyngiomas. GTR was performed in 14 (64%) patients. Postoperatively, 12/14 (86%) cases improved visually, and 20 (91%) needed hormone replacement therapy. There was no difference in BMI evolution in the GTR versus STR group, cognitive status was stable or improved in all patients except 1; 4/8 patients with STR experienced progression needing adjuvant treatment versus no patient with GTR. CONCLUSIONS: EES GTR of grade 2 craniopharyngiomas does not cause major hypothalamic worsening, in contrast with children operated by cranial approaches. The surgeon's experience is key in deciding when to stop the dissection. Offering GTR whenever possible aims at avoiding tumor progression and radiotherapy.

Interhypothalamic adhesions in endoscopic third ventriculostomy.

INTRODUCTION: An interhypothalamic adhesion (IHA) is a gray mater-like band of tissue traversing across the third ventricle anterior to the mammillary bodies and is similar but distinct from an interthalamic adhesion. These rare anatomic anomalies can be detected with magnetic resonance imaging or, incidentally, during endoscopic ventricular surgery. METHODS: All cases of interhypothalamic adhesions visualized during endoscopic third ventriculotomy (ETV), outside of the myelomeningocele setting, were identified from two institutions. Retrospective chart and imaging reviews were conducted and compared to intraoperative videos and photos for all cases. IHA variables collected included the following size, location, multiplicity, and associated anatomic anomalies. RESULTS: Four cases of interhypothalamic adhesions were identified during ETV-all of which, either partially or completely, obscured access to the third ventricular floor. The IHAs in our cohort were duplicated in two patients, large (> 3 mm and severely obstructing access to the third ventricular floor) in three patients, and adherent to the floor of the third ventricle in three patients. All four patients had primary absence of the septum pellucidum. Previous reports found associations of IHAs with other congenital, particularly midline, abnormalities. The IHAs in our cohort affected the surgery in three of four cases including misdirecting the ventriculostomy and requiring retraction or division of the IHA. In no case was postoperative pituitary or hypothalamic dysfunction observed. CONCLUSIONS: Although interhypothalamic adhesions are rare, these anomalies must be recognized as they may hinder access to the third ventricular floor. IHAs may be large, multiple, or adherent to adjacent ventricular structures, they can misdirect or occlude the ventriculostomy or impart risk of bleeding and hypothalamic injury. Techniques for management of IHA include aborting the attempt, re-siting the ventriculostomy, or retracting or dividing the IHA, which enabled technically successful ETV in three of four patients in this series.

Surgical Approaches to the Thalamus in Relation to the White Matter Tracts of the Cerebrum.

BACKGROUND: Approaching the thalamus from any angle remains a challenge because of its deep-seated location and intimate relations with adjacent important neurovascular structures and functions such as relaying sensory and motor signals and cognition. Our aim was to explore the relationship of the white matter tracts of the cerebrum to the thalamus using a fiber dissection technique, to delineate anatomic principles of approaches to the thalamus, and to discuss the tracts at risk in relation to each approach. METHODS: The thalamus was subdivided into 6 different regions and 13 approaches were examined in an attempt to describe a surgical road map. RESULTS: To reach the anteroinferior, medial, and lateral parts of the thalamus, the anterior and middle group approaches were used, and to reach the posterosuperior and posteroinferior thalamus, posterior and middle group approaches were used. The anteroinferior zone was the most difficult site to be accessed and the posterosuperior thalamus had the maximum number of alternative approaches. The distal transsylvian approach to the posterosuperior thalamus and the supracarotid infrafrontal approach to the anteroinferior thalamus had the highest number of neural structures severed within the surgical corridor. The infratentorial approaches and the suboccipital transtentorial approach preserve most of the white matter tracts en route to the posterosuperior and medial posteroinferior parts of the thalamus. CONCLUSIONS: When the surgical approaches for thalamic lesions are defined, white matter tracts along the surgical route should be taken into consideration.

Endoscopic Hematoma Evacuation for Intracerebral Hemorrhage Under Local Anesthesia: Factors That Affect the Hematoma Removal Rate.

OBJECTIVE: Recent advances in endoscopic surgery have led to more patients being able to undergo endoscopic removal of hypertensive intracerebral hemorrhage (HICH). However, because of the minimal invasiveness, endoscopic HICH removal through a narrow surgical window can result in a low removal rate. The goal of the present study was to investigate the factors that affect the removal rate of HICH evacuation. METHODS: The data from 28 patients with supratentorial HICH who had undergone endoscopic hematoma evacuation were retrospectively analyzed. The inclusion criteria were spontaneous supratentorial HICH with a hematoma volume >30 mL, admission to the hospital within 24 hours of ictus, and a Glasgow coma scale score of ≥4. RESULTS: Of the 28 patients, 9 were women and 19 were men, ranging in age from 41 to 86 years (mean, 60.7 ± 12.7). The hematoma location was the basal ganglia in 25 patients and subcortical in 3 patients. The mean preoperative hematoma volume was 62.4 ± 22.5 mL. The hematoma removal rate was <60% for 11 patients (poor evacuation group) and ≥60% for in 17 patients (good evacuation group). Comparing the 2 groups, chronic renal failure treated with hemodialysis (P = 0.0072, χ2 test), liver cirrhosis (P = 0.023, χ2 test), and surgeon experience with ≥10 cases of endoscopic HICH removal (P = 0.016, χ2 test) were significant factors related to the HICH removal rate. CONCLUSION: To achieve a good removal rate, surgeons should have experience performing the endoscopic procedure. Also, patients with end-stage chronic renal failure or liver cirrhosis should be excluded.

Flexible endoscopically assisted evacuation of acute and subacute subdural hematoma through a small craniotomy: preliminary results.

BACKGROUND: The first choice to treat acute subdural hematoma (SDH) is a large craniotomy under general anesthesia. However, increasing age or comorbid burden of the patients may render invasive treatment strategy inappropriate. These medically frail patients with SDH may benefit from a combination of small craniotomy and endoscopic hematoma removal, which is less invasive and even available under local anesthesia. Although hematoma evacuation with a rigid endoscope for acute or subacute SDHs has been reported in the literature, use of a flexible endoscope may have distinct advantages. In this article, we attempted to clarify the utility of small craniotomy evacuation with a flexible endoscope for acute and subacute SDH in the elderly patients. METHOD: Between November 2013 and September 2016, a total of 17 patients with acute SDH (15 patients), subacute SDH (1 patient), or acute aggravation of chronic SDH (1 patient) underwent hematoma evacuation with a flexible endoscope at our hospital and were enrolled in this retrospective study. Either under local or general anesthesia, the SDH was removed with a flexible suction tube with the aid of the flexible endoscope through the small craniotomy (3 × 4 cm). Hematoma evacuation rate, improvement of clinical symptoms, and procedure-related complications were evaluated. RESULTS: Hematoma evacuation rate was satisfactory, and statistically significant clinical improvement was observed in postoperative Glasgow Coma Scale in all cases compared to the preoperative assessment. No procedure-related hemorrhagic complications were observed. CONCLUSIONS: The results reported here suggest that small craniotomy evacuation with a flexible endoscope is a safe, effective, and minimally invasive treatment for acute and subacute SDH in selected cases.

Endoscopic Carpal Tunnel Release with and without Sedation.

BACKGROUND: This study evaluated outcomes and complications with endoscopic carpal tunnel release performed with local anesthesia only versus local anesthesia with sedation. The authors hypothesized that patient outcomes and satisfaction would be equivalent in both groups irrespective of anesthesia type. METHODS: One hundred fifty-four consecutive patients undergoing endoscopic carpal tunnel release with local anesthesia either with or without sedation were prospectively enrolled in a study of satisfaction and outcomes. Patients were surveyed preoperatively and at 2 weeks and 3 months postoperatively to evaluate satisfaction, symptoms, complications, and disability using the 11-question Disabilities of the Arm, Shoulder, and Hand questionnaire survey; the Levine-Katz carpal tunnel survey; and a customized Likert scale. RESULTS: The hypothesis was upheld. Patients reported high levels of satisfaction (96 percent in the local anesthesia group and 93 percent in the local anesthesia with sedation group at 3 weeks). Disability, pain, and symptom scores did not differ significantly between groups at either postoperative time point. After surgery, patients in the sedation group recalled more mean preoperative anxiety (four of 10 versus 2.03 of 10 at 3 months). If they were to undergo surgery again, patients in the sedation group were likely to desire either sedation (68 percent) or general anesthesia (29 percent), whereas patients in the local anesthesia-only group were likely to wish for similar local-only anesthesia (78 percent). There were no reoperations or epinephrine-related complications in either group. CONCLUSIONS: Patients undergoing endoscopic carpal tunnel release with the local anesthesia or local anesthesia plus sedation experience similar levels of satisfaction and outcomes. Both methods of anesthesia provide excellent results and allow surgeons and patients to choose freely between the two anesthetic techniques.

Paratrigeminal, Paraclival, Precavernous, or All of the Above? A Circumferential Anatomical Study of the C3-C4 Transitional Segment of the Internal Carotid Artery.

BACKGROUND: Although the term paraclival carotid pervades recent skull base literature, no clear consensus exists regarding boundaries or anatomical segments. OBJECTIVE: To reconcile various internal carotid artery (ICA) nomenclatures for transcranial and endoscopic-endonasal perspectives, we reexamined the transition between lacerum (C3) and cavernous (C4) segments using a C1-C7 segments schema. In this cadaveric study, we obtained a 360°-circumferential view integrating histological, microsurgical, endoscopic, and neuroradiological analyses of this C3-C4 region and identified a distinct transitional segment. METHODS: In 13 adult, silicone-injected, formalin-fixed cadaveric heads (26 sides), transcranial-extradural-subtemporal and endoscopic-endonasal CT-guided dissections were performed. A quadrilateral area was noted medial to Meckel's cave between cranial nerve VI, anterolateral and posterolateral borders of the lateral-paratrigeminal aspect of the precavernous ICA, and posterior longitudinal ligament. Endoscopically, a medial-paraclival aspect was defined. Anatomical correlations were made with histological and neuroradiological slides. RESULTS: We identified a distinct precavernous C3-C4 transitional segment. In 18 (69%) specimens, venous channels were absent at the quadrilateral area, on the paratrigeminal border of the precavernous ICA. A trigeminal membrane, seen consistently on the superior border of V2, defined the lateral aspect of the cavernous sinus floor. The medial aspect of the precavernous ICA corresponded with the paraclival ICA. CONCLUSION: Our study revealing the juncture of 2 complementary borders of the ICA, endoscopic endonasal (paraclival) and transcranial (paratrigeminal), reconciles various nomenclature. A precavernous segment may clarify controversies about the paraclival ICA and support the concept of a "safe door" for lesions involving Meckel's cave, cavernous sinus, and petrous apex.

Effectiveness of Intraventricular Endoscopic Lamina Terminalis Fenestration in Comparison with Standard ETV: Systematic Review of Literature.

BACKGROUND: Endoscopic third ventriculostomy is a consolidated technique for the treatment of hydrocephalus. Despite its effectiveness and feasibility, several technical limitations about its use in certain situations have been described. Lamina terminalis-endoscopic third ventriculostomy (LT-ETV) has been proposed as an alternative technique. Authors systematically reviewed the literature in order to define the effectiveness and limits in comparison with standard ETV. METHODS: This systematic review followed the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) statement. It has also been registered with the PROSPERO International Prospective Register of Systematic Reviews (CRD42016041596). MEDLINE, Web of Knowledge, and EMBASE were independently searched. RESULTS: Seven studies were found to be eligible. A case of ours was added to the series, totaling 41 patients (mean patient age ± SD was 21.6 ± 20.7 years). Endoscopic findings leading surgeons to perform LT-ETV were abnormal ventricular anatomy (24, 57%), inadequate/insufficient interpeduncular subarachnoid space (11, 26%), a combination of both (5, 12%), and intraoperatory, unsatisfactory third ventricle floor fenestration (2, 5%). Most common pathologies were neurocysticercosis (12, 28.57%), aqueductal stenosis (8, 19%), tuberculous meningitis (4, 9.52%), and medulloblastoma (3, 7.14%). A flexible endoscope was the most used device (36 procedures, 86%), while not determining a statistical relevant diminution of complications in comparison with a rigid endoscope (P = 1.0). An overall success rate of 69% was registered, increasing to 89% if just the first year of follow-up was considered. CONCLUSIONS: LT-ETV can be considered a successful technical option when standard ETV cannot be performed, although more complex cerebrovascular anatomy is involved. Therefore we suggest that lateral terminalis fenestration is a valid technical option in experienced hands.

Endoscopic management of a low-grade thalamic glioma: a safe alternative to open microsurgery?

BACKGROUND: Despite considerable advances in preoperative and intraoperative imaging and neuronavigation, resection of thalamic gliomas remains challenging. Although both endoscopic biopsy and third ventriculostomy (ETV) for the treatment of secondary hydrocephalus are commonly performed, endoscopic resection of thalamic gliomas has been very sparsely described. METHOD: We report and illustrate the surgical procedure and patient's outcome after full endoscopic resection of a thalamic glioma and to discuss this approach as an alternative to open microsurgery. RESULTS: In 2016, a 56-year-old woman presented with disorientation, dysphasia and right facial hypaesthesia in our department. Cranial magnetic resonance imaging revealed a left thalamic lesion and subsequent hydrocephalus. Initially, hydrocephalus was treated by ETV but forceps biopsy was not diagnostic. However, metabolism in 18F-fluoroethyl-L-tyrosine positron emission tomography indicated glioma. Subsequently, endoscopic and neuronavigation-guided tumour resection was performed using a <1 cm2, trans-sulcal approach through the left posterior horn of the lateral ventricle. While visibility was poor using the intraoperative microscope, neuroendoscopy provided excellent visualisation and allowed safe tumour debulking. Neither haemorrhage from the tumour or collapse of the cavity compromised endoscopic resection. CONCLUSIONS: In accordance with one previously published case of endoscopic resection of a thalamic glioma, no surgery-related complications were observed. Although this remains to be determined in larger series, endoscopic resection of these lesions might be a safe and feasible alternative to biopsy or open surgery. Future studies should also aim to identify patients specifically eligible for these approaches.