'What's in a name', a systematic review of the pterional craniotomy for aneurysm surgery and its many modifications with a proposal for simplified nomenclature.

BACKGROUND: The pterional or frontosphenotemporal craniotomy has stood the test of time and continues to be a commonly used method of managing a variety of neurosurgical pathology. Already described in the beginning of the twentieth century and perfected by Yasargil in the 1970s, it has seen many modifications. These modifications have been a normal evolution for most neurosurgeons, tailoring the craniotomy to the patients' specific anatomy and pathology. Nonetheless, an abundance of variations have appeared in the literature. METHODS: A search strategy was devised according to the 2020 Preferred Reporting Items of Systematic Reviews and Meta-Analyses (PRISMA) statement. To identify articles investigating the variations in the pterional approach, the following search terms were applied: (pterional OR minipterional OR supraorbital) AND (approach OR craniotomy OR technique). RESULTS: In total, 3552 articles were screened with 74 articles being read in full with 47 articles being included for review. Each article was examined according the name of the technique, temporalis dissection technique, craniotomy technique and approach. CONCLUSION: This systematic review gives an overview of the different techniques and modifications to the pterional craniotomy since it was initially described. We advocate for the use of a more standardised nomenclature that focuses on the target zone to simplify the management approach to supratentorial aneurysms.

The Learning Curve for Endoscopic Endonasal Transsphenoidal Pituitary Surgery: Evaluating Endocrine Outcomes.

OBJECTIVE: In South Australia endoscopic endonasal approach (EEA) pituitary surgery has been practiced since 2006, largely by two neurosurgeons with a small fellowship-trained otolaryngology team. The aim of this cohort study was to determine if a "learning curve" can be established over this time period, as represented by structural and endocrine patient outcomes. METHOD: Retrospective cohort study of patients undergoing EEA surgery between 2006 and 2021 in Adelaide, South Australia at three tertiary teaching hospitals.. Cases were divided by each surgeon and split into groups of sequential 40 cases. Endocrine assessment pre- and post-operatively involved static pituitary and end-organ hormones, with dynamic tests as required, assessed by an pituitary endocrinologist. Each hormonal axis (gonadal, cortisol, thyroid, prolactin and growth hormone) was documented preoperatively and at an early and long term follow up at 1-2 and 12 months, respectively. RESULTS: The study included a cohort of 443 pituitary adenomas managed with endoscopic endonasal transsphenoidal surgery in a consecutive fashion between two neurosurgeons over 16-years. Gross tumour resection but not visual visual outcomes improved with surgical experience but this outcome may be neurosurgeon dependent. Endocrine outcomes were not consistently improved with experience, but lower rates of hypopituitarism were seen with experience with one neurosurgeon. Average follow up was approximately 5 years, and a minimum follow up of 12 months for all patients. CONCLUSIONS: We present long term endocrine follow up for patients with functional and non-functional adenomas. Improved rates of gross tumour resection were evident with with surgical experience. However, there was no apparent change in post-operative endocrine outcomes.

Pituitary carcinoma - case series and review of the literature.

Although pituitary adenomas (PAs) account for 15% of intracranial tumors, pituitary carcinomas (PCs) are a rare entity. Most commonly, PCs evolve from aggressive PAs invading the surrounding structures and eventually leading to metastatic lesions. Due to the low incidence, the diagnosis and treatment remains challenging. We report a case series of five patients with pituitary carcinoma (PC) treated in our center. At first diagnosis 3 patients had an ACTH-producing adenoma, 1 a prolactinoma and 1 a double secreting adenoma (GH and prolactin). The mean time interval from initial diagnosis to diagnosis of PC was 10.7 years (range 5-20 years). All patients underwent multiple surgical resections and radiotherapy. Four patients were treated with temozolomide for metastatic disease. One patient with concomitant radiochemotherapy for local recurrence. Temozolomide led to a stable disease in 2 patients. One patient had a progressive disease after 9 cycles of temozolomide. In absence of standard treatment, immunotherapy was initiated, resulting in a stable disease. We report five cases of PCs. Three patients obtained a stable disease after tailored multidisciplinary treatment. Additionally, one patient was treated with immunotherapy, opening a new treatment option in PCs. Overall, PCs are rare intracranial neoplasms occurring several years after the initial diagnosis of aggressive PAs. Currently, the absence of predictive factors for an aggressive clinical course, provokes a challenging management.

Aneurysmal subarachnoid haemorrhage in Indigenous and non-Indigenous Australians: A retrospective study assessing patient characteristics and outcome.

INTRODUCTION: Smoking and hypertension are prevalent among Indigenous Australians (Aboriginal and Torres Strait Islanders). We investigated if these risk factors suggest a greater rate of aneurysmal subarachnoid haemorrhage in Indigenous Australians (IA) compared to non-IA. MATERIALS AND METHODS: A retrospective cross-sectional study was performed on data retrieved from the Nationwide Hospital Morbidity Database for all aSAH cases in Australia between 2012 and 2018. Patient characteristics, radiological findings, aneurysm characteristics, treatment characteristics and discharge outcomes were assessed. Crude and age-adjusted incidences, trends of aSAH and case fatality rate over time were calculated. RESULTS: A total of 12,286 patients were included (285 IA, 12,001 non-IA). Indigenous aSAH patients were significantly younger than non-IA, with 89.8 percent of IA younger than 65 years old (p < 0.001). Crude annual incidences were similar between the 2 cohorts, however age-adjusted incidence shows a RR = 1.4 at 45-59 years in IA patients, compared with their non-IA counterparts. 30-day mortality was similar between the two groups, at 25.3 and 26.9% for IA and non-IA groups, respectively. CONCLUSION: This 10 year nationwide retrospective study highlights a disparity between the crude and age-adjusted incidence of aSAH in IA compared to non-IA.

Randomized Trial Comparing Burr Hole Craniostomy, Minicraniotomy, and Twist Drill Craniostomy for Treatment of Chronic Subdural Hematoma.

BACKGROUND: The mainstay of treatment for symptomatic or large chronic subdural hematoma (CSDH) is surgery, but controversy still exists regarding the best surgical technique. Three different techniques are commonly used: burr hole craniostomy (BHC), minicraniotomy (MC), and twist drill craniostomy (TDC). OBJECTIVE: To determine which surgical technique for drainage of CSDH offers best results. METHODS: We set up a multicenter prospective randomized trial (Comparison of Chronic Subdural Hematoma Treatment [COMPACT] trial) comparing BHC, MC, and TDC for the surgical treatment of CSDH. The primary end point was reoperation rate, and secondary end points included complication rates and clinical outcome. Patients were considered to have good outcome when they did not undergo reoperation, suffered no surgical or medical complication, and had no related mortality. Clinical outcome was also evaluated by evolution of the Markwalder score and the modified Rankin score. RESULTS: Two-hundred forty-five patients were included in the final analysis: 79 BHC, 84 MC, and 82 TDC. Mean duration of surgery was shorter for TDC than for BHC and MC ( P < .001). Reoperation rate was 7.6% for BHC, 13.1% for MC, and 19.5% for TDC ( P = .07). This trend toward better results for BHC was not statistically significant in logistic regression analysis. The proportion of patients with good outcome was 78.5% for BHC group, 76.2% for MC, and 69.5% for TDC ( P = .4). Evolution of the Markwalder score and modified Rankin score were not significantly different between treatment groups. CONCLUSION: All 3 techniques are effective at treating patients with CSDH with eventual 6-month outcome being similar. Although not reaching statistical significance in our study, BHC offers the lowest recurrence rate combined with manageable complication rate.

The O-Arm as an Additional Tool to Confirm Optimal Ventricular Tip Position-A Technical Note.

BACKGROUND: Ventricular catheter placement can be a challenging procedure when treating patients with slit ventricles, despite the use of a neuronavigation system. METHODS: We report the case of 3 patients with idiopathic intracranial hypertension who had required revision of their ventricular catheter due to malpositioning, despite initial placement using neuronavigation. Owing to the absence of intraoperative computed tomography in our center, we used the O-arm imaging system to confirm placement of the optimal ventricular tip position intraoperatively. RESULTS: Optimal ventricular drain position was achieved in all 3 patients. CONCLUSIONS: This short technical note describes an easy technique for using the O-arm to confirm the optimal ventricular drain position.

The surgical management of intraoperative intracranial internal carotid artery injury in open skull base surgery-a systematic review.

Intraoperative internal carotid artery (ICA) injury during open skull base surgery is a catastrophic complication. Multiple techniques and management strategies have been reported for endoscopic skull base surgery; however, the literature on managing this complication in open skull base surgery is limited. To perform a systematic review and give an overview of the different techniques described to manage this complication intraoperatively, a systematic review was conducted in PubMed, Ovid Medline, Ovid Embase and Scopus for literature published until July 2021. Titles and abstracts were screened. Studies meeting prespecified inclusion criteria were reviewed in full. PRISMA guidelines were strictly adhered to. Out of 4492 articles, only 12 articles could be included, reflecting an underreporting of open skull base ICA injuries. Multiple techniques can be used depending on the location and size of the injury as well as the surgeon's experience. Described techniques include the following: a primary repair via a micro-suture or nonpenetrating clips; wrapping or plugging; coating; occlusion of the parent artery with or without a bypass; packing with further endovascular management. A treatment algorithm is proposed.

Management of an Internal Carotid Artery Injury During Open Skull Base Surgery With a Crushed Muscle Patch - Technical Note and Lessons Learned.

BACKGROUND: Iatrogenic internal carotid artery (ICA) injury is a catastrophic complication in open skull base surgery. There is a lack of information regarding the most appropriate techniques on how to manage this complication. OBJECTIVE: To highlight the difficulties encountered when an ICA injury arises intraoperatively and discuss the role and the potential pitfalls of the crushed muscle patch in the management of an ICA injury during open skull base surgery. METHODS: In this technical video, we demonstrate the management of intraoperative ICA injury, which occurred during the resection of a diffuse planum sphenoidale meningioma via a left pterional craniotomy. RESULTS: When isolation of the defect with temporary clips failed, we opted for a crushed muscle graft to plug the defect. Hemostasis was achieved, but because of prolonged pressure application and "overpacking," the parent vessel was occluded. CONCLUSION: The crushed muscle patch can be easily applied; however, care must be taken not to "overpack" and occlude the ICA.

Syringomyelia intermittens: highlighting the complex pathophysiology of syringomyelia. Illustrative case.

BACKGROUND: Chiari Type I malformation (CM1) is a disorder recognized by caudal displacement of the cerebellar tonsils through the foramen magnum and into the cervical canal. Syringomyelia is frequently found in patients with CM1, but the pathophysiology of syringomyelia remains an enigma. As a general consensus, symptomatic patients should be treated and asymptomatic patients without a syrinx should not be treated. Mildly symptomatic patients or asymptomatic patients with a syrinx, on the other hand, pose a more challenging dilemma, as the natural evolution is uncertain. For many surgeons, the presence of a syrinx is an indication to offer surgery even if the patient is asymptomatic or mildly symptomatic. OBSERVATIONS: The authors describe an illustrative case of a 31-year-old female with an incidental finding of a CM1 malformation and cervical syrinx in 2013. Conservative management was advocated as the patient was asymptomatic. Monitoring of the syrinx over a course of 8 years showed resolution, followed by reappearance and finally a complete resolution in 2021. A review of the literature and the possible pathophysiology is discussed. LESSONS: The unusual course of this patient highlights the importance of guiding treatment by clinical symptoms, not radiological findings. Furthermore it reflects the complexity of the pathophysiology and the uncertain natural history of syringomyelia.

Kinked Perforator Due to Clipping of Parent Vessel Aneurysm: Technical Note and Lessons Learned.

BACKGROUND: Adverse outcomes after aneurysm clipping can be potentially reversible, when managed appropriately. METHODS: This is a case report describing kinking of a perforator due to clipping of parent vessel aneurysm. RESULTS: Complete recovery of a high-grade motor deficit was achieved after instant reintervention with application of smaller clips in combination with gelfoam soaked in papaverine. CONCLUSION: Use of evoked potentials and intraoperative digital subtraction angiography are recommended and may help in preclinical diagnosis. Knowledge of delayed perforator kinking as a complication may lead to a more rapid diagnosis and management.

Posterior approach for anteriorly located cervical spinal cord hemangioblastomas: technical note.

The surgical management of anteriorly located spinal cord hemangioblastomas remains a challenge. Different approaches have been published, of which the anterior approach seems to be the most obvious and commonly used. A posterior approach might be more suitable in certain patients, especially in cases of cystic hemangioblastomas. The authors present 3 cases of anterior spinal hemangioblastomas, which were all resected via a posterior approach. The authors discuss the rationale for choosing this approach and explain the technique in detail.