Caroline Hayhurst

Tuberculum sella meningioma.

Tuberculum sellae (TS) meningiomas represent a distinct subgroup of anterior cranial fossa meningiomas with distinctive features. Early visual deterioration with optic canal infiltration occurs because of the site of dural origin. The expanded endonasal transsphenoidal approach and the eyebrow supraorbital craniotomy have been advocated as minimally invasive techniques for TS meningiomas. The authors review the current literature on minimally invasive techniques for TS meningiomas to define visual outcomes, extent of resection, and operative morbidity associated with each approach and highlight pertinent features of individual tumors, which favor either a cranial or an endonasal approach to achieve optimal outcomes.

Results with Expanded Endonasal Resection of Skull Base Meningiomas Technical Nuances and Approach Selection Based on an Early Experience.

AIM Reconstruction technique advances have created renewed enthusiasm for the expanded endonasal approach (EEA). However, as with any new technique, early experiences inevitably lead to more selective use of these techniques. We reviewed our experience of the expanded endonasal endoscopic approach for skull base meningiomas and place it in context of the literature. MATERIAL AND METHODS We performed retrospective review of all endonasal cases performed at our center for histologically proven meningioma. Tumor locations in 26 patients included the olfactory groove (n=9), tuberculum sellae (n=7), optic nerve sheath (n=1), planum sphenoidale (n=2), clival (n=1) petroclival (n=3), cavernous sinus (n=2) and extensive pan-basal meningioma (n=1). RESULTS The median follow-up was 38.6 months. Excluding 3 patients with tumors found incidentally, pre-operative symptoms improved in 14 of 23 (61%), were the same in 8 of 23 (35%) and worsened in one of 23 patients (4%) at time of last follow-up. Of all 26 patients, 16 (62%) had complete macroscopic resection of their tumor, 5 (19%) underwent at least 90% resection, and 5 (19%) underwent subtotal resection. There were two neurological complications and one cerebrospinal fluid leak. CONCLUSION This study presents outcomes of patients treated with endonasal endoscopic meningioma surgery. We believe that very low rates of morbidity can be achieved in carefully selected patients, thus avoiding brain manipulation.

Contemporary management of low-grade glioma: a paradigm shift in neuro-oncology

Supratentorial diffuse intrinsic low-grade gliomas represent a distinct but heterogenous group of tumours, with the propensity to grow and to differentiate into malignant tumours. They have been historically viewed in the ‘benign’ spectrum of intrinsic brain tumours, so a watch-and-wait policy was often adopted. With recent advances in our understanding of the natural history of these tumours, combined with advances in surgical technique, an aggressive approach is now recommended. Increasing quality evidence of the impact of tumour resection and multicentre trials of adjuvant radiotherapy and chemotherapy have led to a new algorithm for low-grade glioma management. This review aims to outline the emerging evidence that has shifted neuro-oncology practice.

Use of day 1 early morning cortisol to predict the need for glucocorticoid replacement after pituitary surgery

Background. Assessment of adrenal reserve in patients who have undergone pituitary surgery is crucial. However, there is no clear consensus with regards to the type and timing of the test that should be used in the immediate post-operative period. Recently, there has been increased interest in measuring post-operative cortisol levels. We present our data utilising day 1 post-operative early morning cortisol as a tool to assess adrenal reserve in steroid-naive patients. Methods. A retrospective analysis of endoscopic pituitary surgery undertaken over a 2-year period. 82 patients underwent 84 surgeries in total. Patients who were already on glucocorticoids pre-operatively and patients with Cushings disease, pituitary apoplexy and those without follow-up data were excluded, leaving a study group of 44 patients with 45 operations. A 9am day 1 post-operative cortisol value of > 400 nmol/L was taken as an indicator of adequate adrenal reserve. All the patients were reassessed at 6 weeks with a standard short synacthen test (SST) using 250 micrograms of intravenous synacthen. Results. 22 out of 45 patients had a cortisol value of > 400 nmol/L on day 1 post-operatively and were discharged without glucocorticoid supplementation. Of these, only 2 patients subsequently failed the SST when reassessed at 6–8 weeks. The remaining 23 patients had a cortisol value of < 400 nmol/L on day 1 post-operatively and were discharged on hydrocortisone 10 mg twice daily. At 6–8 weeks, nine continued to show suboptimal stimulated cortisol levels whereas the remaining fourteen patients showed adequate adrenal reserve. The 9 am cortisol value had high specificity (81.8%) and positive predictive value (90.9%) for integrity of the HPA axis. Sensitivity was 58.8% and negative predictive value was 39.1%. Conclusion. A day 1 post-operative early morning cortisol is a useful tool to predict adrenal reserve post-pituitary surgery, enabling clinicians to avoid unnecessary blanket glucocorticoid replacement.

Cerebral salt wasting following traumatic brain injury

Summary Hyponatraemia is the most commonly encountered electrolyte disturbance in neurological high dependency and intensive care units. Cerebral salt wasting (CSW) is the most elusive and challenging of the causes of hyponatraemia, and it is vital to distinguish it from the more familiar syndrome of inappropriate antidiuretic hormone (SIADH). Managing CSW requires correction of the intravascular volume depletion and hyponatraemia, as well as mitigation of on-going substantial sodium losses. Herein we describe a challenging case of CSW requiring large doses of hypertonic saline and the subsequent substantial benefit with the addition of fludrocortisone. Learning points: The diagnosis of CSW requires a high index of suspicion. Distinguishing it from SIADH is essential to enable prompt treatment in order to prevent severe hyponatraemia. The hallmarks of substantial CSW are hyponatraemia, reduced volume status and inappropriately high renal sodium loss. Substantial volumes of hypertonic saline may be required for a prolonged period of time to correct volume and sodium deficits. Fludrocortisone has a role in the management of CSW. It likely reduces the doses of hypertonic saline required and can maintain serum sodium levels of hypertonic saline.

Rapid regression of a symptomatic pineal region meningioma after presumed spontaneous central infarction.

Dear Sir, A 73-year-old type 2 diabetic female presented to our department with severe headaches, drowsiness and cognitive decline. On admission she was confused with a GCS of 13 (E3, V4, M6). There was no evidence of meningism but she had a low-grade pyrexia of 37.7°. MRI demonstrated significant ventriculomegaly with periventricular T2 signal change and a large pineal region mass with a maximum diameter of 40 mm (Fig. 1). The mass was irregularly ring enhancing with a low signal intensity core. Diffusion-weighted imaging showed restriction within the lesion. An emergency endoscopic third ventriculostomy (ETV) was undertaken, and via a second burr hole and separate trajectory, image-guided biopsy and aspiration of the lesion were attempted, in view of the possibility of intracerebral abscess. However, the biopsy only revealed reactive tissue and aspiration was unsuccessful. There was no evidence of infection on microbiology. After ETV the patient made an excellent clinical recovery to GCS 15. Following post-operative treatment with dexamethasone, a repeat CT showed that the lesion had reduced to 32 mm maximum diameter. Repeat image-guided biopsy was performed 7 days later, which revealed a WHO grade 1 meningioma with no atypical features and evidence of necrosis. The patient was discharged with planned readmission 8 weeks later for resection of the pineal region meningioma but on pre-operative imaging the lesion had regressed further to a new maximum diameter of 23.4 mm (Fig. 2a). She was also completely asymptomatic, so the decision was made to defer surgery and pursue surveillance imaging. The meningioma has since been followed up with 6-monthly CT scans, with the maximum diameter gradually reducing in size to 18 mm over a 3-year period (Fig. 2b). The patient remains well with no neurological deficit and has returned to all normal activities. Our case most likely represents central infarction in a meningioma that became acutely symptomatic and subsequently regressed. Central infarction secondary to hypoperfusion is recognised as an uncommon cause for the acute presentation of meningioma, with resulting vasogenic cerebral oedema and raised intracranial pressure reported [1]. In our case, there was evidence of central tumour infarction and necrosis on CT. In the literature there are a small number of cases of central infarction of meningioma, all suggesting a precipitating cause * Luke Galloway lukegalloway14@hotmail.com

Diffuse low grade glioma after the 2016 WHO update, seizure characteristics, imaging correlates and outcomes

OBJECTIVES The majority of patients with supratentorial diffuse grade II glioma present with seizures, which adversely affect quality of life. The exact mechanism of epileptogenesis is unknown and the influence of tumour characteristics, radiological and histological, are not well studied, particularly following the introduction of molecular genetics in the 2016 WHO reclassification of gliomas. We sought to define predictors of seizure development and outcome in low grade glioma. PATIENTS AND METHODS A retrospective review of patients who underwent resection of a supratentorial grade II glioma in a single institution. All patients underwent surgery at initial presentation with the aim of maximal safe resection. Presenting symptoms and radiological variables were recorded, including eloquent location, cortical involvement, tumour margins and tumour volume. Extent of resection (EOR), surgery type (awake vs asleep) and seizure outcome were analysed. Using molecular genetics data the original histology was reclassified according to the 2016 WHO update. RESULTS 63 patients were included, 45 (71%) presented with seizures. 36 (57%) had oligodendroglioma and 27 astrocytoma. IDH-1 mutation was present in 53 (84%). 18 (29%) had tumour in an eloquent location. 33 (73%) were Engel class I following surgery at median follow up of 43 months. 6 patients were Engel II, 6 class III. Complete and near total resection were associated with improved Engel class compared to subtotal resection. No factors such as age, tumour location, tumour margins or tumour molecular genetics (including IDH-1 mutation) predicted better seizure outcome. Updated histological subtype did not predict the presence of seizures at initial diagnosis, only tumour heterogeneousity on initial MRI (p = 0.043). More patients who underwent awake craniotomy with intraoperative mapping were Engel class 1 post-operatively than those operated under general anaesthetic (84% vs 65%). Tumour volume at presentation did not correlate with seizure outcome but impacts on the EOR. CONCLUSION Seizure outcome is directly related to EOR in low grade glioma, which can be predicted by the initial tumour volume. Tumour histological subtype, including updated molecular genetic classification did not predict seizure development or outcome in this series. The use of awake craniotomy results in greater EOR and improved Engel Class following surgery.

Orbitocerebral mucormycosis and intracranial haemorrhage: a role for caution with steroids in suspected giant cell arteritis

A 75-year-old man with type 2 diabetes mellitus presented with complete loss of vision in his right eye and severe headaches for the past 24 hours. He had been treated for suspected giant cell arteritis (GCA) with high-dose corticosteroids which were being tapered to stop after an inconclusive right temporal artery biopsy and an erythrocyte sedimentation rate (ESR) value of 8. His current acute presentation, however, raised further concern for partially treated GCA and precipitated treatment with pulsed methylprednisolone. The patient, taking metformin, developed diabetic ketoacidosis and was transferred to the intensive care unit where a swollen, painful right eye with chemosis and complete ophthalmoplegia was subsequently revealed to be secondary to cavernous sinus thrombosis. Rhino-orbital skin necrosis with positive samples for the organism Rhizopus on eventual orbital exenteration revealed angioinvasive fungal infection, mucormycosis, to be the cause. We discuss here the lessons learnt, and how best to treat a susceptible cohort within our ageing western population.

Pineal parenchymal tumours of intermediate differentiation – An evidence-based review of a new pathological entity

Abstract Pineal region lesions are uncommon, and pineal parenchymal tumours (PPT) account for 20–30% of tumours in this area of which pineocytomas (PCs) and pineoblastomas (PBs) are more prevalent. In 2007, the World Health Organisation (WHO) reclassified PPT from two subgroups (PC and PB) into four, including pineal parenchymal tumours of intermediate differentiation (PPTID). PPTID have been further divided into low- and high-grade lesions (WHO II and III), but due to their rarity have proven difficult lesions to diagnose and a paucity of literature means their optimal treatment options are a challenge to define. This article is a review of the literature of PPTID highlighting diagnostic criteria, a discussion on the role of surgery and radiotherapy, including treatment paradigms and reported outcomes for these problematic neoplasms.

Electromagnetic Neuronavigation for CNS Tumors

The integration of image guidance into all neurosurgical procedures is fast becoming routine. Most navigation systems are based on optical tracking and therefore require a direct line of sight between camera and tracking probe, interfering with theatre workflow and freedom of movement within the surgical field. Electromagnetic (EM) neuronavigation overcomes many of the obstacles inherent in optical systems and provides rapid, real time, accurate navigation. The advantages of EM navigation are outlined and the potential applications in neuro-oncology, including awake craniotomy and endonasal transphenoidal skull base procedures are highlighted.