Daniele Bongetta

Central and peripheral components of writing critically depend on a defined area of the dominant superior parietal gyrus

Classical neuropsychological models of writing separate central (linguistic) processes common to oral spelling, writing and typing from peripheral (motor) processes that are modality specific. Damage to the left superior parietal gyrus, an area of the cortex involved in peripheral processes specific to handwriting, should generate distorted graphemes but not misspelled words, while damage to other areas of the cortex like the frontal lobe should produce alterations in written and oral spelling without distorted graphemes. We describe the clinical and neuropsychological features of a patient with combined agraphia for handwriting and typewriting bearing a small glioblastoma in the left parietal lobe. His agraphia resolved after antiedema therapy and we tested by bipolar cortical stimulation his handwriting abilities during an awake neurosurgical procedure. We found that we could reversibly re-induce the same defects of writing by stimulating during surgery a limited area of the superior parietal gyrus in the same patient and in an independent patient that was never agraphic before the operation. In those patients stimulation caused spelling errors, poorly formed letters and in some cases a complete cessation of writing with minimal or no effects on oral spelling. Our results suggest that stimulating a specific area in the superior parietal gyrus we can generate different patterns of agraphia. Moreover, our findings also suggest that some of the central processes specific for typing and handwriting converge with motor processes at least in the limited portion of the superior parietal gyrus we mapped in our patients.

Low-Cost Fluorescein Detection System for High-Grade Glioma Surgery

BACKGROUND Intraoperative fluorescein detection has been used in the fields of vascular and oncologic neurosurgery since 1948. Modifications of the optics in order to enhance the fluorescence contrast under microscopic view have been developed by many authors. The industries, during the past 10 years, provided commercial high-cost optimized apparatuses. Reviewing the literature, we found that the prototypical techniques were definitely inexpensive but lacked reliability, reproducibility, and standard legal norms. METHODS We describe the developing of a fluorescein detection system that could be economic, simple, effective, and law abiding. RESULTS We employed a commercial violet-blue filter designed for fluorescein excitation in endoscopic procedures and used commercial photographic yellow optical filters for fluorescence detection. All the instrumentation is cleared for clinical use, and its cost is up to 200 times lower than commercial apparatuses. CONCLUSION Our results show a good distinction of fluorescein-stained structures, with overall acceptable operating light conditions.

Are antiplatelet and anticoagulants drugs a risk factor for bleeding in mild traumatic brain injury

OBJECTIVE Facing mild traumatic brain injury, clinicians must decide whether to perform a computed tomography (CT) scan to detect a potential intracranial hemorrhage. Many useful guidelines have been developed for the general population, but there is no general consensus about the best practice to adopt when dealing with patients on antiplatelet or anticoagulation drugs. The relatively recent introduction of new anticoagulants and second-generation antiplatelet drugs poses new challenges in this field. There are no data in the literature about the relative risk of intracranial bleeding in such categories. METHODS We enrolled 2773 consecutive patients presenting at our emergency department with mild traumatic brain injury as chief complaint and evaluated the results of their head CT scans, stratifying their anticoagulation and/or antiplatelet drug regime. RESULTS Of these patients, 1608 matched the criteria for head CT scan and had a Glasgow Coma Scale (GCS) score of 15; 517 were on antiplatelet drugs, whereas 213 were on anticoagulants. The risk of developing intracranial bleeding was significantly higher for patients on antiplatelet drugs, whereas the risk of anticoagulated patients overlapped with that of the general population. The trend for second-generation drugs was of higher risk of bleeding only for antiplatelets. CONCLUSIONS Patients with a GCS score of 15 on long-term anticoagulation therapy seem to be at no higher risk for intracranial hemorrhage than are nonanticoagulated patients. On the contrary, patients with a GCS score of 15 on antiplatelet therapy seem to be more prone to developing intracranial bleeding than are the general population, with a trend to be more at risk when it comes to second-generation drugs.

Poor man's fluorescence and equipment.

Dear Editor, We have read with great interest the debate on the use of fluorescein during high-grade glioma surgery. Three consecutive letters to the editor outlined two factions: those against, and those in favor of the use of fluorescein, which has been labeled as the Bpoor man’s fluorescence^ [2, 3, 5, 7]. We strongly agree with Brawanski et al. in stating that any technical innovation potentially increasing our surgical skills should be welcomed [3]. Nevertheless, we partially disagree in stating that the difference between 5-ALA and fluorescein is not really a problem of poor man–rich man fluorescence. Moreover, we maintain that much research and trials still need to be performed in order to fully evaluate and compare these two methods and we leave to more experienced surgeons the specific analyses of their respective benefits and liabilities. Still, we deem that cost issues are not to be overlooked. Albeit with some conflicts of interests, Slof et al. and Esteves et al. have actually demonstrated the costeffectiveness of 5-ALA, whose cost of a single dose is reported to be around 1,000 euros [4, 6]. Still, their models only make vague references to the cost of the instrumentation needed not giving a real picture of the cost of this new technology. To our knowledge, at least in Europe, there are two companies currently with dedicated fluorescence filters for both 5-ALA and fluorescein (Karl Zeiss, Oberkochen, Germany, and Leica Microsystems,Wetzlar, Germany). Although these companies are both to be commended for their efforts in the development of such systems, new technologies come with a price to be paid. In particular, both systems reportedly need a cuttingedge microscope and an accessory module, implying that the encompassing total cost easily exceeds a few hundred thousand euros. All the centers involved in the debate are wellrenowned, high-volume centers which strive to perform pioneering techniques on the basis of costly, resourcedemanding equipment, whose implementation is often immediate; but what about the rest of the world, i.e., the low-volume settings or, more relevantly, the developing countries, which struggle in providing medical care? In a spending-review setting involving many aspects of the health system worldwide, we have developed a method of providing a low-cost fluorescein detection system. Other pioneering works reported their custom settings but the novelty of this approach is the fact that it employs low-cost, already widespread surgical technologies. Briefly, we employed a blue filter designed for fluorescein detection in endoscopic procedures connected to a xenon light source and fixed the light cable to a standard retractor blade applied to the head holder. As for fluorescence detection, we purchased commercial yellow optical filters (for less than 50 euros), which have been modified to fit in the microscope oculars: no structural change has been made to the microscope and the system can be easily mounted and easily removed during the operation. The endoscopic technology is already widespread in neurosurgical centers and, as a reference, in our region the commercial system employed amounts to less than 1,000 euros. Relying on this Bpoor man’s technology ,̂ we are currently recruiting patients for a phase II trial (BGLOWOMA: Glioma I, Daniele Bongetta, certify that this manuscript is a unique submission and is not being considered for publication, in part or in full, with any other source in any medium.

Chordoid glioma: a rare radiologically, histologically, and clinically mystifying lesion

Chordoid glioma (CG) is a rare central nervous system neoplasm (WHO grade II) of uncertain origin whose typical localization is in the anterior part of the third ventricle. Its clinical, radiological, and histological features may vary and furthermore mimic other kind of benign lesions usually associated with a better outcome. We report a case of a 43-year-old female who underwent gross total removal of a lesion of the third ventricle causing hydrocephalus. The imaging studies and the intraoperative examination led at first to a hypothesis of meningioma. Early surgical and neurological outcomes were good. The patient underwent multiple complications related to hypothalamic dysfunctions and thrombohemorragic issues and eventually died because of systemic infections. Definitive examination was of chordoid glioma of the third ventricle. Reviewing literature, we evaluated possible pitfalls in radiological and histological diagnosis as well as in surgical and medical treatment of CGs. Despite their benign presentation, a high incidence of multiple possible severe complications is reported. Early alertness and combined treatment strategies could improve overall CGs treatment strategies.

Strokectomy and Extensive Cerebrospinal Fluid Drainage for the Treatment of Space-Occupying Cerebellar Ischemic Stroke

BACKGROUND Cerebellar ischemia may lead to space-occupying edema, resulting in potentially fatal complications. Different surgical procedures are available to create space for the swollen ischemic brain; however, the type and timing of surgical treatments remain topics of debate in the literature. Here we report a case series of patients treated with a unilateral craniotomy to perform a cerebellar strokectomy and extensive cerebrospinal fluid (CSF) drainage without osteodural posterior fossa decompression. METHODS We retrospectively analyzed the clinical and radiographic data of 11 patients with posterior fossa ischemia who underwent surgery at one of our institutions. A statistical analysis was performed to identify potential predictive factors for functional outcome. RESULTS The mean patient age was 64.7 years. The involved vascular territory was the Posterior inferior cerebellar artery in 9 patients (82%) and the anterior inferior cerebellar artery/superior cerebellar artery in 2 patients (18%). The mean Glasgow Coma Scale score was 13.6 on admission, but 9.3 immediately before surgery. The surgical procedure was performed in a mean of 36.8 minutes after the radiologic diagnosis of space-occupying edema. Clinical outcome at 6 months was good (modified Rankin Scale [mRS] score ≤2) in 9 patients (82%). Surgery-related complications occurred in 2 patients (18%), and these was a single death (9%) not related to the procedure or posterior fossa compression. Matching patients with their mRS outcome evaluation, the sole variable significantly associated with good outcome was age at admission (62.1 vs. 76.5 years; P < 0.05). CONCLUSIONS Unilateral suboccipital craniotomy with strokectomy and extensive CSF drainage may allow for satisfactory decompression of the ischemic posterior fossa with acceptable morbidity and mortality rates, especially in younger patients.

Could Thalidomide Be a Treatment Option for Arteriovenous Malformations

LETTER: We read with great interest the article by Pabaney et al. 1 on the development of a de novo arteriovenous malformation (AVM) and their review of the literature. Besides their praiseworthy effort to collect and analyze all the sporadic literature reports, the authors are to be commended for trying to stress and explain the dynamic manifestation of AVMs. In this regard, they emphasize the potential role of vascular endothelial growth factor pathway activation induced by other factors or insults. In particular, in their case report, they infer that an ischemic event acted like a “second hit” to an existing genetic aberrancy. Their hypothesis is that after a stressing event, the cerebral endothelial structures may be subjected to the effect of an angiogenic niche, which could dynamically challenge the stability of the vascular architecture, leading to the development or enlargement of an AVM.

Intraregional differences of perioperative management strategy for lumbar disc herniation: is the Devil really in the details?

Background This study intends to evaluate whether regional common habits or differences in case-volume between surgeons are significative variables in the perioperative management of patients undergoing surgery for lumbar disc herniation. Methods An e-mail survey was sent to all neurosurgeons working in Lombardy, Italys most populated region. The survey consisted of 17 questions about the perioperative management of lumbar disc herniation. Results Forty-seven percent (47%) out of 206 Lombard neurosurgeons answered the survey. Although in some respects there is clear evidence in current literature on which is the best practice to adopt for an optimal management strategy, we noticed substantial differences between respondents, not only between hospitals but also between surgeons from the same hospital. Still, no differences were evident in a high vs low case-volume comparison. Conclusion We identified no regional clusterization as for practical principles in the perioperative management of lumbar disc herniation and neither was case-volume a significative variable. Other causes may be relevant in the variability between the perioperative management and the outcomes achieved by different specialists.

Fluorescein-guided intraoperative endoscopy in patients with hereditary hemorrhagic telangiectasia: first impressions

Hereditary hemorrhagic telangiectasia (HHT) is a rare genetic disease that results in mucocutaneous telangiectasias and arteriovenous visceral malformations. Nasal telangiectasias lead to recurrent epistaxis, which affects up to 96% of patients. Different morphologic classifications and methods of visualization of nasal lesions have been described in the literature. We developed a new method of intraoperative endoscopy based on the intravenous administration of fluorescein. Preliminary data of this technique are reported.

Endovascular embolization of pial arteriovenous fistula fed from P1 segment of posterior cerebral artery in 12 years old girl: case report and review of literature

Objective Intracranial pial arteriovenous fistulas (PAVFs) are rare vascular lesions with peculiar epidemiological, morphological, and pathophysiological characteristics. Since there is no nidus, PAVF treatment has been performed by direct disconnection of the arteriovenous communication via a surgical, endovascular, or a combined approach. We aim to outline the relevant variables to consider in planning an endovascular treatment strategy. Methods We present a case of a 12 year old girl with a single feeder PAVF originating from the first segment (P1) of the left posterior cerebral artery with a varicose venous drainage into the right cavernous sinus. Results We report the successful endovascular exclusion of the fistula with the release of a total of 27 detachable platinum coils with no complications at follow-up. Treatment strategy and nuances are discussed along with a review of the literature. Conclusions Morphology, age, embolization strategies, and materials are the different variables to be analyzed in the endovascular treatment of such lesions.