Ranjeev Bhangoo

Papillary glioneuronal tumour: a review of the literature with two illustrative cases

Abstract We report two cases of papillary glioneuronal tumour (PGNT). One was located in the supratentorial parenchyma and the other was intraventricular. Both patients underwent gross total resection of their tumour and have returned to normal lifestyle. Papillary glioneuronal tumor is a recently described rare cerebral neoplasm. Recently classified by the World Health Organization in 2007 as a Grade I neuronal-glial tumour, these tumours are infrequent lesions that can be challenging to the practising pathologist. Patients commonly present with headaches or seizures, but may be asymptomatic with the mass discovered incidentally. The characteristic radiological, histological and immunohistochemical features are discussed. Surgical excision has been curative in most of the cases with only a handful of cases of recurrence reported. The increasing number of reports in the literature shows how PGNT forms a good example of a newly diagnosed tumour category in evolution. New classifications and re-classifications of broad categories of brain tumours will hopefully lead to a narrower diagnostic, prognostic and therapeutic profile. The even rarer presence of atypia calls for longer follow-up to help elucidate further its biological behaviour.

Natural history of supratentorial hemangioblastomas in von Hippel-Lindau disease.

BACKGROUNDSupratentorial hemangioblastomas are rare lesions, occurring either sporadically or in von Hippel-Lindau disease. OBJECTIVEFollowing recent advances in our understanding of the natural history of von Hippel-Lindau–associated cerebellar and spinal hemangioblastomas, we conducted a study of the natural history of supratentorial hemangioblastomas in von Hippel-Lindau disease. METHODSWe reviewed a series of 18 supratentorial hemangioblastomas in 13 patients with von Hippel-Lindau disease. Clinical, genetic, and serial imaging data and operative records were analyzed. RESULTSHemangioblastomas were most commonly seen in the temporal lobe. Only 6 tumors had a cyst at diagnosis or during follow-up, and only 6 patients had associated symptoms at presentation or during follow-up. The most frequent clinical presentations were intracranial hypertension and visual loss. Of 14 tumors with documented serial imaging, 13 demonstrated tumor growth. Rates and patterns of tumor growth were unique to each patient. The mechanism of cyst formation described in other locations was also demonstrated in the supratentorial region. Patterns of peritumoral edema and rate of cyst formation seemed to be influenced by the presence of anatomic barriers. Germline VHL mutation was identified in all patients, but no specific genotype-phenotype correlation was found, although a familial predisposition is suggested. CONCLUSIONThis series illustrates the wide variation in tumor locations, patterns of growth, and edema progression seen in supratentorial hemangioblastomas and adds to our knowledge of the natural history of hemangioblastomas.

Active dendritic cell immunotherapy for glioblastoma: Current status and challenges

Abstract Dendritic cell (DC) immunotherapy is developing as a promising treatment modality for patients with glioblastoma multiforme (GBM). The aim of this article is to review the data from clinical trials and prospective studies evaluating the safety and efficacy of DC vaccines for newly diagnosed (ND)- and recurrent (Rec)-GBM and for other high-grade gliomas (HGGs). By searching all major databases we identified and reviewed twenty-two (n = 22) such studies, twenty (n = 20) of which were phase I and II trials, one was a pilot study towards a phase I/II trial and one was a prospective study. GBM patients were exclusively recruited in 12/22 studies, while 10/22 studies enrolled patients with any diagnosis of a HGG. In 7/22 studies GBM was newly diagnosed. In the vast majority of studies the vaccine was injected subcutaneously or intradermally and consisted of mature DCs pulsed with tumour lysate or peptides. Median overall survival ranged between 16.0 and 38.4 months for ND-GBM and between 9.6 and 35.9 months for Rec-GBM. Vaccine-related side effects were in general mild (grade I and II), with serious adverse events (grade III, IV and V) reported only rarely. DC immunotherapy therefore appears to have the potential to increase the overall survival in patients with HGG, with an acceptable side effect profile. The findings will require confirmation by the ongoing and future phase III trials.

Resection of olfactory groove meningioma - a review of complications and prognostic factors

Introduction. High complication rates have been cited following olfactory groove meningioma (OGM) resection but data are lacking on attendant risk factors. We aimed to review the complications following OGM resection and identify prognostic factors. Methods. A retrospective review was performed on 34 consecutive patients who underwent primary OGM resection at a single London institution between March 2008 and February 2013. Collected data included patient comorbidities, pre-operative corticosteroid use, tumour characteristics, imaging features, operative details, extent of resection, histology, use of elective post-operative ventilation, complications, recurrence and mortality. Results. Complication rate was 39%. 58% of complications required intensive care or re-operation. Higher complication rates occurred with OGM > 40 mm diameter versus ≤ 40 mm (53 vs. 28%; p = 0.16); OGM with versus without severe perilesional oedema (59 vs. 19%; p = 0.26), more evident when corrected for tumour size; and patients receiving 1–2 days versus 3–5 days of pre-operative dexamethasone (75 vs. 19%; p = 0.016). Patients who were electively ventilated post-operatively versus those who were not had higher risk tumours but a lower complication rate (17 vs. 44%; p = 0.36) and a higher proportion making a good recovery (83 vs. 55%; p = 0.20). Complete versus incomplete resection had a higher complication rate (50 vs. 23%; p = 0.16) but no recurrence (0 vs. 25%; p = 0.07). Conclusion. Risk of morbidity with OGM resection is high. Higher complication risk is associated with larger tumours and greater perilesional oedema. Pre-operative dexamethasone for 3–5 days versus shorter periods may reduce the risk of complications. We describe a characteristic pattern of perilesional oedema termed ‘sabre-tooth’ sign, whose presence is associated with a higher complication rate and may represent an important radiological prognostic sign. Elective post-operative ventilation for patients with high-risk tumours may reduce the risk of complications.

Is referral to the neuro-oncology MDT safe?

Abstract Introduction. Since 2006, National Institute for Health and Clinical Excellence (NICE) guidelines advise referral of any suspected brain tumour to a dedicated neuro-oncology multidisciplinary team (MDT). We investigated two aspects of MDT safety: whether time to operation was delayed and whether brain abscesses were inappropriately referred to the MDT. Material(s) and methods. We reviewed the notes of 220 consecutive patients referred to our neuro-oncology service before and after implementation of a pre-operative MDT meeting. Results. Median time to operation was similar for patients referred before and after introduction of the MDT (8 days pre-MDT, 9 days post-MDT). There were four abscesses referred via the MDT with a significantly longer median time to operation than in the pre-MDT era (6 days vs. 1 day), although no patient came to any apparent harm as a consequence. No lesion imaged with MRI was misdiagnosed. Discussion. Pre-operative MDT does not lengthen time to operation for patients with brain tumour. However, it may delay time to operation for abscesses inadvertently referred via the MDT route. We advocate the use of MRI to minimise the risk of misdiagnosis of cerebral abscesses.

Good outcome following emergency decompressive craniectomy in a case of malignant middle cerebral artery infarction in a 14-month-old infant

Abstract We report the case of a 14-month-old infant presenting with unresponsiveness and seizure following thoracic surgery. Imaging showed full territory left middle cerebral artery infarct and signs of raised intracranial pressure (ICP) that required emergency decompressive craniectomy (DC). The child made a good functional recovery. We discuss the case.

Peduncular hallucinosis and cerebellar cognitive affective syndrome: Letter to the editor

In the March 2009 issue of Acta Neurochirurgica, Miyazawa et al. suggest that peduncular hallucinosis (PH) can occur in the absence of direct brainstem injury as a result of retraction-related cerebellar oedema, in a case of microvascular decompression for trigeminal neuralgia. They postulate that this may involve the mechanism seen in cerebellar cognitive affective syndrome (CCAS) [4]. At a time of great interest in attributing localisation importance to symptoms of hallucination, PH was first described by Jean Lhermitte in 1922, in a 72 year old who experienced headache, vomiting, vertigo, bizarre visual hallucinations in association with ptosis, ophthalmoplegia and cerebellar and pyramidal signs, suggesting a pontine/ midbrain lesion [3]. At that time, contemporary ideas on the function of hallucinations in neurological localisation had been summarised by the neurosurgeon Gilbert Horrax, assistant to Harvey Cushing at the Brigham Hospital and later Chief of Neurosurgery at the Lahey Clinic: localisation of unformed or elemental visual hallucinations (e.g. lights or spots) was to the calcarine area and localisation of formed hallucinations (e.g. objects or people) to temporal lobe tumours [1, 2]. Contrary to standard thinking, therefore, Lhermitte localised the hallucinations of his patient to a lesion of the midbrain and pontine regions, and in the context of a deranged sleep-wake cycle, as during these hallucinations the patient was both awake and aware that they were not real. Current knowledge, however, is that even though PH can be caused by isolated midbrain lesions, these are not the only cause. Isolated lesions in the thalamus or the substantia nigra pars reticulata can cause PH. Risser and Powell thus suggested the term Lhermitte’s hallucinosis to avoid anatomic confusion [7]. The authors’suggestion of a relation between PH and CCAS may be tentative, but is interesting. CCAS comprises impairment of executive function, visuospatial organisation and memory, non-motor language, affect regulation and personality [8]. It is attributed to the disruption of cerebellar modulation of the circuitry that links the prefrontal, posterior parietal, superior temporal and limbic cortices with the cerebellum. It has been observed in groups of patients with different cerebellar abnormalities and lesions. Going a small step further, similarities exist between CCAS and cerebellar mutism syndrome (CMS) where retraction injury, among several others, has been noted to be a causative factor [5, 9]. Hence, whereas the cerebellum has traditionally been thought of as coordinating and controlling purposeful movement, there is clear and mounting evidence—case reports, functional neuroimaging and neuropsychology— that supports a role for the cerebellum in higher cognitive function: in language, cognitive behaviour, emotional behaviour and executive function. Support for this notion is rendered by the neuropsychological dysfunction observed in children with posterior fossa tumours where damage to the dentate nuclei and inferior vermis seems to be implicated. Furthermore, there may even be a lateralisation effect in that damage to the right sided dentate nucleus and cerebellum—linked to the dominant hemisphere—was associated with lower scores in verbal and performance IQ than the left [6]. Loops from the dentate nucleus project back to the posterior parietal cortex, superior temporal sulcus and frontal regions (cortico-ponto-cerebellar pathways), implying a cerebellar role in modifying information that arrives from association cortices. While currently there is a paucity of evidence for a direct mechanism of injury that would influence surgical techActa Neurochir (2010) 152:379–380 DOI 10.1007/s00701-009-0412-4

Navigated Transcranial Magnetic Stimulation In A Patient With A Cranioplasty In Situ: A Safe And Accurate Procedure

BACKGROUND Navigated transcranial magnetic stimulation (nTMS) is a nonsurgical mapping technique used in mapping of motor and language eloquent areas within and/or surrounding brain tumors. Previous reports support this as a safe technique with minor side effects associated with minor headaches and discomfort around the stimulation area. Currently there are no published reports concerning the accuracy and safety of this procedure in patients with a titanium cranioplasty in situ. CASE PRESENTATION A 59-year-old lady was diagnosed with a recurrent glioma in the context of increasing seizure frequency, left-sided numbness, and weakness. She was diagnosed with a World Health Organization grade 2 oligodendroglioma 10 years before her presentation, which was initially treated with radiotherapy and then surgical resection of this lesion 5 years later. The procedure was complicated with a wound infection, treated with a craniectomy and wound washout, followed by a titanium cranioplasty. Before proceeding with surgery for recurrence, nTMS was performed for motor mapping. No complications were identified. She underwent a craniotomy for tumor resection with aminolevulinic acid HCl (Gliolan), and the tumor was completely removed. Intraoperatively, the direct cortical stimulation correlated with the preoperative nTMS. The pathologic diagnosis on recurrence was an anaplastic oligodendroglioma grade III, and the patient is currently undergoing adjuvant chemotherapy. CONCLUSION This report confirms that nTMS is a safe and accurate procedure in patients who have a titanium cranioplasty in situ.

Posterior longitudinal ligament and its implications in intradural cervical disc herniation: Case report and review of the literature

Background: Intradural disc herniations (IDH) are rare, particularly in the cervical spine, where they account for less than 5% of all discs. Adhesions between the ossified/calcified posterior longitudinal ligament (OPLL), dura, and ossified/calcified disc herniations increase the complexity of resecting these cervical lesions. Case Description: A 42-year-old male presented with a rapidly progressive cervical myelopathy over a 2-month period. This was attributed to an ossified/calcified intradural cervical disc herniation in conjunction with OPLL. The anterior cervical discectomy and fusion (ACDF) resulted in a dural defect but there was no cerebrospinal fluid (CSF) fistula as the arachnoid membrane remained intact. Had there been a CSF leak, it would have warranted both wound-peritoneal (WP) and lumbo-peritoneal shunts (LP). The surgeons should have anticipated that a CSF leak would likely occur prior to performing the ACDF, and should have prophylactically prepared and draped the abdomen for a potential WP, followed by a LP shunt. Three months postoperatively, the patients proprioceptive deficit improved, and he almost completely recovered motor function. Conclusion: Performing an ACDF for resection of an intradural calcified/ossified disc with OPLL often results in both a dural defect and CSF fistula. As the arachnoid membrane rarely remains intact, the spine surgeon should be prepared to immediately perform both a WP shunt, and subsequently, an LP. In this case, following an ACDF, resection of an intradural ossified disc with OPLL resulted in an isolated dural defect without a CSF fistula and did not require no dural repair or shunting procedures.

Commentary: Giuseppe Campani (1635-1715, Rome, Italy): the First Use of a Microscope in Medicine and Surgery

Abstract Giuseppe Campani (1635‐1715) was a polymath in Rome, Italy, during the Scientific Revolution in the XVIIth century. In particular, he forged the screw barrel microscope and was manufacturing his own lenses for microscopes and telescopes. He mastered the art of lens grinding. Those lenses have been analyzed with modern methods and turned out to be of extremely good quality, shining light on the fact that Giuseppe Campani mastered the theories of optics. Moreover, in a letter that Giuseppe Campani sent to Pope Innocent XI, he clearly described the use of a microscope for the examination of wounds of legs. This letter dates back to 15 August 1686 and is the first evidence of the use of microscopes to analyze wounds, sores, and anatomic specimens in medical and surgical settings. MG Yasargil previously showed the lithography accompanying this letter and was the first to recognize its great importance. We accessed this original letter in the Vatican Library, and for the first time we have translated it from Latin to English in order to unveil its significance in the context of the Scientific Revolution and the history of medicine and surgery.