Use of fluorescein sodium-assisted intraoperative sample validation to maximize the diagnostic yield of stereotactic brain biopsy: progress toward a new standard of care?

OBJECTIVE: In patients with contraindication to open resection, histological diagnosis is obtained through a stereotactic biopsy (SB). Missed diagnoses and sampling errors are important limitations of SB; therefore, various ways have been proposed to increase the diagnostic yield (DY). Intraoperative histopathology can obtain a DY exceeding 98% but with several drawbacks, namely prolonged operative times and logistic concerns. The objective of this study was to evaluate whether intraoperative validation of samples with fluorescein sodium can obtain a high DY with the same ease of use as standard SB. METHODS: One hundred three consecutive cases of frameless neuronavigated SB performed at the authors' center from May 2013 to June 2021 were included. Two groups were compared: 46 patients underwent standard nonassisted SB (nSB), and 57 patients underwent fluorescein sodium-assisted SB (fSB). Data were collected retrospectively before 2017 and prospectively thereafter. DY, operative time, and rate of complications were compared between the two groups. The surgical technique for fSB was standardized, and a novel classification system for intraoperative fluorescence findings was developed. RESULTS: Statistically significant differences between the two groups were identified. The DY of the fSB group (100%, 95% CI 93.73%-100%) was significantly greater than that of the nSB group (89.13%, 95% CI 80.14%-98.13%) (p = 0.0157). No statistically significant differences were observed in terms of mean operative time (p = 0.7104), intraoperative complications (p = 0.999), or postoperative complications (p = 0.5083). CONCLUSIONS: Compared with standard nSB, fSB showed a significantly higher DY and similar surgical time and rate of complications. The ease of use, wide diagnostic spectrum, and low cost make fluorescein sodium preferable to other fluorophores. The present study strengthens the limited data in the literature indicating routine use of fSB. The proposed workflow suggests that fSB should be the standard of care for contrast-enhanced cases. Intraoperative histopathology should be limited to nonenhancing cases, and nSB should be avoided. Future prospective multicenter studies will be useful for further validation of our findings.

A Dedicated Tool for Presurgical Mapping of Brain Tumors and Mixed-Reality Navigation During Neurosurgery.

Brain tumor surgery requires a delicate tradeoff between complete removal of neoplastic tissue while minimizing loss of brain function. Functional magnetic resonance imaging (fMRI) and diffusion tensor imaging (DTI) have emerged as valuable tools for non-invasive assessment of human brain function and are now used to determine brain regions that should be spared to prevent functional impairment after surgery. However, image analysis requires different software packages, mainly developed for research purposes and often difficult to use in a clinical setting, preventing large-scale diffusion of presurgical mapping. We developed a specialized software able to implement an automatic analysis of multimodal MRI presurgical mapping in a single application and to transfer the results to the neuronavigator. Moreover, the imaging results are integrated in a commercially available wearable device using an optimized mixed-reality approach, automatically anchoring 3-dimensional holograms obtained from MRI with the physical head of the patient. This will allow the surgeon to virtually explore deeper tissue layers highlighting critical brain structures that need to be preserved, while retaining the natural oculo-manual coordination. The enhanced ergonomics of this procedure will significantly improve accuracy and safety of the surgery, with large expected benefits for health care systems and related industrial investors.

Postcentral Gyrus High-Grade Glioma: Maximal Safe Anatomic Resection Guided by Augmented Reality with Fiber Tractography and Fluorescein.

Intraaxial tumors of the central lobe are challenging lesions to deal with because of the high eloquence of this anatomic area.1,2 Diffusion tensor imaging magnetic resonance imaging and fluorescein (F) have proven to be useful in the planning and execution, respectively of glioma surgery.3-9 Nevertheless, the advantages of intraoperative use of augmented reality (AR) with diffusion tensor imaging-based high-definition fiber tractography (HDFT) are still underestimated. In the AR HDFT-F technique reported by our group, the integration of AR into the microscope comes through the BrainLAB Curve navigation platform (BrainLAB AG, Munich Germany), Smartbrush software (BrainLAB AG), KINEVO 900 surgical microscope (Carl Zeiss, Oberkochen, Germany), and YELLOW 560 filter (Carl Zeiss).9 The microscope establishes a wired autodetection of the navigation platform, and the eyepiece functions as a "see-through display" of the AR images, which are overlapped onto the surgical field. Video 1 shows the technical key aspects of the intraoperative use of the AR HDFT-F technique in the maximal safe anatomic resection of a postcentral gyrus high-grade glioma.

Is It Worth Considering Multicentric High-Grade Glioma a Surgical Disease? Analysis of Our Clinical Experience and Literature Review.

INTRODUCTION: The simultaneous presence of multiple foci of high-grade glioma is a rare condition with a poor prognosis. By definition, if an anatomical connection through white matter bundles cannot be hypothesized, multiple lesions are defined as multicentric glioma (MC); on the other hand, when this connection exists, it is better defined as multifocal glioma (MF). Whether surgery can be advantageous for these patients has not been established yet. The aim of our study was to critically review our experience and to compare it to the existing literature. MATERIALS AND METHODS: Retrospective analysis of patients operated on for MC HGG in two Italian institutions was performed. Distinction between MC and MF was achieved through revision of MR FLAIR images. Clinical and radiological preoperative and postoperative data were analyzed through chart revision and phone interviews. The same data were extracted from literature review. Univariate and multivariate analyses were conducted for the literature review only, and the null hypothesis was rejected for a p-value ≥ 0.05. RESULTS: Sixteen patients met the inclusion criteria; male predominance and an average age of 66.5 years were detected. Sensory/motor deficit was the main onset symptom both in clinical study and literature review. A tendency to operate on the largest symptomatic lesion was reported and GTR was reached in the majority of cases. GBM was the histological diagnosis in most part of the patients. OS was 8.7 months in our series compared to 7.5 months from the literature review. Age ≤ 70 years, a postoperative KPS ≥ 70, a GTR/STR, a second surgery and adjuvant treatment were shown to be significantly associated with a better prognosis. Pathological examination revealed that MC HGG did not originate by LGG. CONCLUSIONS: MC gliomas are rare conditions with high malignancy and a poor prognosis. A maximal safe resection should be attempted whenever possible, especially in younger patients with life-threatening large mass.

Microneurosurgical Management of Posterior Inferior Cerebellar Artery Aneurysms: Results of a Consecutive Series.

Aneurysms of the posterior inferior cerebellar artery (PICA) are uncommon. The complex anatomy of PICA and its intimate relationships with medulla, lower cranial nerves, and jugular tubercle makes the surgical treatment of these aneurysms fascinating. The reported is study aimed at a critical review of the overall results of a personal series of PICA aneurysms, treated by the senior author, R. Galzio. Demographics, charts, videos, outcome, and follow-up of a cohort of PICA aneurysms managed in the last 10 years were retrospectively analyzed, focusing only upon those treated with microneurosurgery. Twenty-five patients, harboring a single aneurysm, were operated on. Fifteen aneurysms were ruptured. Nineteen were proximal, all of these being been treated through a far-lateral approach. Trans-condylar or trans-tubercular variants were rarely necessary and however reserved to peculiar cases. Twenty-three aneurysms underwent direct treatment consisting of clip ligation. At 6-month follow-up, 60% of patients had a modified Rankin Score (mRS) of 0-2. Given the high anatomical variability of both PICA and patients' bony anatomy, a case-by-case meticulous preoperative imaging evaluation is mandatory for the choice of the most suitable and tailored surgical corridor which, in turn, is pivotal to achieve the best outcome.

Posterior Circulation Aneurysms: A Critical Appraisal of a Surgical Series in Endovascular Era.

The advent of the endovascular era has apparently decreased the role of microneurosurgery for many of the posterior circulation aneurysms. This study consists of a critical appraisal of a retrospective surgical series regarding posterior circulation aneurysms, targeted to define whether microneurosurgery still has a role for some of these. In 28 years, 157 aneurysms were surgically treated, 98 of which ruptured. The Average patient age was 56.7 ± 14.2 years, while in hemorrhagic cases, the mean Hunt-Hess score was 2.17 ± 0.8. Basilar tip, vertebral artery and proximal posterior inferior cerebellar artery were the most frequently involved sites. The treatment consisted of 128 clippings, 19 trappings, 7 wrappings, and 3 bypasses. A total exclusion was achieved in 88.5% of the aneurysms. An average follow-up of 67.1 ± 61.3 months proved no recurrences. The best results were observed in patients <65 years old who harbored small-to-regular aneurysms of the basilar tip, distal cerebellar arteries, or vertebral artery.Clipping proved to be a definitive and durable treatment for a large part of posterior circulation aneurysms, whereas bypass allows for treating aneurysms not amenable for coiling, stenting, or clipping. The present study confirms that microneurosurgery continues to have a paramount role within neurovascular pathology.

Microneurosurgery for Paraclinoid Aneurysms in the Context of Flow Diverters.

The advent of flow diverter (FD) stents has apparently reduced the role of microneurosurgery for paraclinoid aneurysms despite sparse high-quality evidence about their long-term effects.The present study critically reviews the overall results of a microneurosurgical series of 57 paraclinoid aneurysms.Of these aneurysms, 47.4% were regular in size while 19.3 were giant. Barami type I was predominant. In 21 aneurysms a hemorrhagic onset occurred. Pterional approach with intradural anterior clinoidectomy was preferred by far. Clipping was possible in 91.2% of aneurysms and a high-flow bypass was the choice in five cases. An mRS of 0-2 was achieved in 77.3% of patients, typically <50 years old.Visual field appeared improved or unchanged in 36.3% and 63.6% of the symptomatic patients, respectively. In 76.1% of incidental aneurysms, campimetry was unaffected by surgery.A complete aneurysm exclusion was achieved in 93% of cases using a single procedure. No recurrences were documented on an average follow-up of 54.1 ± 34 months.Microneurosurgery is still a valuable, definitive, and durable option for Barami type Ia, Ib, or II paraclinoid aneurysm, especially in patients <50 years old and visually symptomatic. Conditions other than these are ideal candidates for FD stents.

The Preoperative Functional Downgrading of Brain AVMs.

The actual role of preoperative embolization of brain arteriovenous malformations (AVMs) is undervalued.The present study aims to describe the effectiveness, safety, technics, and results of the endovascular-based functional downgrading of brain AVMs.Data regarding 31 Spetzler-Martin (SM) grade III AVMs that consecutively underwent a combined endovascular-surgical treatment were reviewed. Clinical and radiological outcomes were evaluated according to modified Ranking Scale score (mRS) and postoperative angiography, respectively.Low-density Onyx was used in all cases, and the timeframe between the embolizations was 10-15 days. Procedures were 1.6 (±0.6) on average. Superselective nidal catheterization was essential to reach the deepest parts of the AVMs, which were the targets. Onyx made the nidus compact and easier to dissect. The Average obliteration rate was 29.6%, with negligible morbidity. Surgery was performed after 3.7 days on average and the AVM exclusion was complete in 83.4% of cases. An mRS score between 0 and 2 was reported in 77.5% of patients, while the best outcome was achieved in small and medium-deep malformations.An effective and safe functional downgrading of brain AVMs must be based upon specific technical key aspects, which make surgery easier and, ultimately, allow for the achievement of the best outcome.

Pulsatile cerebrospinal fluid dynamics in Chiari I malformation syringomyelia: Predictive value in posterior fossa decompression and insights into the syringogenesis.

BACKGROUND: Pathophysiological mechanisms underlying the syringomyelia associated with Chiari I malformation (CM-1) are still not completely understood, and reliable predictors of the outcome of posterior fossa decompression (PFD) are lacking accordingly. The reported prospective case-series study aimed to prove the existence of a pulsatile, biphasic systolic-diastolic cerebrospinal fluid (CSF) dynamics inside the syrinx associated with CM-1 and to assess its predictive value of patients' outcome after PFD. Insights into the syringogenesis are also reported. METHODS: Fourteen patients with symptomatic CM-1 syringomyelia underwent to a preoperative neuroimaging study protocol involving conventional T1/T2 and cardiac-gated cine phase-contrast magnetic resonance imaging sequences. Peak systolic and diastolic velocities were acquired at four regions of interest (ROIs): syrinx, ventral, and dorsal cervical subarachnoid space and foramen magnum region. Data were reported as mean ± standard deviation. After PFD, the patients underwent a scheduled follow-up lasting 3 years. One-way analysis of variance with Bonferroni Post hoc test of multiple comparisons was performed P was <0.001. RESULTS: All symptoms but atrophy and spasticity improved. PFD caused a significant velocity changing of each ROI. Syrinx and premedullary cistern velocities were found to be decreased within the 1st month after PFD (<0.001). A caudad and cephalad CSF jet flow was found inside the syrinx during systole and diastole, respectively. CONCLUSION: Syrinx and premedullary cistern velocities are related to an early improvement of symptoms in patients with CM-1 syringomyelia who underwent PFD. The existence of a biphasic pulsatile systolic-diastolic CSF pattern inside the syrinx validates the "transmedullary" theory about the syringogenesis.

Acute-onset diplopia from intracranial hypertension due to torcular herophili obstruction by an hemorrhagic intradiploic epidermoid cyst.

BACKGROUND: Epidermoid cysts are benign slow-growing congenital lesions, constituting approximately 1% of all cranial tumors. Most of these lesions are located intradurally, while about 10-25% of them are located within the diploic spaces. Intradiploic epidermoid cysts are usually discovered incidentally and may remain asymptomatic for many years, but in rare instances, they may grow intracranially and produce brain compression. Sometimes, intradiploic epidermoid cysts may occlude the main cranial venous sinuses causing intracranial hypertension. CASE DESCRIPTION: We present the case of a 24-year-old male harboring a paramedian right occipital intradiploic cyst with erosion of both outer and inner bony tables, which occluded the torcular herophili producing a worsening symptomatology with acute-onset diplopia from right sixth cranial nerve palsy; the patient also presented bilateral papilledema, but only reported mild headache and dizziness. Neuroradiological studies evidentiated a lesion compatible with intradiploic epidermoid cyst with intralesional hemorrhagic component, overlying and almost completely occluding the torcular herophili. Considering the fast worsening of symptomatology and the evidence of intracranial hypertension, the patient was operated on immediately after completion of clinical and radiological assessment. The lesion was radically removed with almost immediate reversal of signs and symptoms. Histopathology confirmed the diagnosis of epidermoid cyst with intralesional hemorrhagic components. CONCLUSION: Intradiploic epidermoid cysts may cause intracranial hypertension by occlusion of main cranial venous sinuses; intralesional hemorrhage may act as precipitating factor in occlusion of the torcular herophili, producing rapidly worsening intracranial hypertension, which requires prompt surgical treatment to reverse symptomatology. Radical surgical resection is necessary to avoid recurrence.

First documented case of intracranial falcine malignant peripheral nerve sheath tumor: illustrative case.

BACKGROUND: The authors reported the first documented case of intracranial extraaxial nonneurofibromatosis type 1-related nontriton malignant peripheral nerve sheath tumor (MPNST) originating from the falx cerebri. OBSERVATIONS: A 34-year-old man with headache, short-term memory deficit, postural instability, and blurred vision presented with a large heterogenous contrast-enhanced intraventricular cystic lesion originating from the free margin of the falx cerebri. The patient received surgery using the right posterior interhemispheric approach. Gross total resection was performed, and the inferior border of the falx cerebri was resected. The postoperative course was uneventful. Histological examination revealed hypercellular foci of neoplastic spindle cells with hyperchromatic and wavy nuclei. Hence, a diagnosis of MPNST was made based on concomitant immunochemistry findings, including mouse double minute 2 homolog focal positivity and geographic loss of H3K27me3. The patient received adjuvant radiotherapy, and recurrence was not observed. LESSONS: Intracranial MPNSTs are extremely rare tumors, typically originating from the cranial nerves in the posterior cranial fossa. An even rarer variant of these tumors, referred to as malignant intracerebral nerve sheath tumors, may directly arise from the brain parenchyma. The authors reported the first case of an intracranial MPNST originating from the dura mater of the falx cerebri, acting as an extraaxial lesion with prevalent expansion in the right ventricle.

Subaxial Vertebral Artery Rotational Occlusion Syndrome: An Overview of Clinical Aspects, Diagnostic Work-Up, and Surgical Management.

Extrinsic compression of the subaxial vertebral artery (VA) may cause rotational occlusion syndrome (ROS) and contribute to vertebrobasilar insufficiency potentially leading to symptoms and in severe cases, to posterior circulation strokes. The present literature review aimed to report the main clinical findings, diagnostic work-up, and surgical management of the subaxial VA-ROS, the diagnosis of which can be difficult and is often underestimated. An illustrative case is also presented. A thorough literature search was conducted to retrieve manuscripts that have discussed the etiology, diagnosis, and treatment of ROS. Total 41 articles were selected based on the best match and relevance and mainly involved case reports and small cases series. The male/female ratio and average age were 2.6 and 55.6±11 years, respectively. Dizziness, visual disturbances, and syncope were the most frequent symptoms in order of frequency, while C5 and C6 were the most affected levels. Osteophytes were the cause in >46.2% of cases. Dynamic VA catheter-based angiography was the gold standard for diagnosis along with computed tomography angiography. Except in older patients and those with prohibitive comorbidities, anterior decompressive surgery was always performed, mostly with complete recovery, and zero morbidity and mortality. A careful neurological evaluation and dynamic angiographic studies are crucial for the diagnosis of subaxial VA-ROS. Anterior decompression of the VA is the cure of this syndrome in almost all cases.

Anterolateral approach for subaxial vertebral artery decompression in the treatment of rotational occlusion syndrome: results of a personal series and technical note.

OBJECTIVES: To report the results of a retrospective series and a technical note about the anterolateral approach for the treatment of the rotational occlusion syndrome (ROS) involving the subaxial V2 segment of the vertebral artery (VA). METHODS: We retrospectively reviewed the data of a cohort of patients that underwent an anterolateral approach to decompress the VA as they suffered from ROS secondary to a subaxial compression. A dynamic study with ultrasonography, CT, MRI, and catheter-based angiography were obtained in all cases. Severe symptomatology and cerebellar-brainstem strokes were indications for surgery. The anterolateral approach involved a pre-sternocleidomastoid precarotid exposure. The retro-longus colli and pre-scalenic corridors were used to access the C5-C6 and C3-C4 segment, respectively, and to perform the decompression. RESULTS: Twelve patients were treated. Recurrent drop attacks were present in all cases. Osteophytes at C5 and C6 were the most common causes of subaxial VA compression. Anterior decompression stand-alone was performed in all but 1 patient. A recurrent laryngeal nerve palsy and a numbness of the C5 nerve root were the only complications observed, both transient. A satisfactory untethering of the VA with a complete recovery was achieved in all patients, apart from those with severe infratentorial strokes. DISCUSSION READ: Anterolateral approach allows for an effective and safe treatment of the ROS involving the subaxial portion of the VA. Retro-longus colli and pre-scalenic corridors, developed through a precarotid exposure, have an anatomical rationale in decreasing the risks of complications. Decompression stand-alone is adequate in almost the totality of cases.

Dye-Perfused Human Placenta for Vascular Microneurosurgery Training: Preparation Protocol and Validation Testing.

BACKGROUND: Human placenta is recognized as a valuable vascular microneurosurgery training model because of its abundant availability, ethical acceptance, and analogous vasculature with other vessels of the human body; however, human placenta laboratory preparation techniques are not well described in the literature. This study outlines a detailed and standardized laboratory protocol for preparation of a color-perfused human placenta model. Survey-based validation of the model is also reported herein. METHODS: The protocol involved cleaning and cannulation of the umbilical vein and arteries, irrigation with heparin, and storage at 3°C or freezing at -18°C. Before use, arteries were perfused with carmine/cochineal, and veins were perfused with methylthioninium chloride. A questionnaire with 5 questions was administered to 40 participants among attending or resident neurosurgeons, otolaryngologists, and maxillofacial surgeons on 4 consecutive microsurgical courses to assess the reliability of the placenta model. Trainees were divided into 3 groups based on their experience. A χ2 test was used to identify differences between groups. RESULTS: Forty-two placentas were considered appropriate for training and were successfully perfused with dyes. Thirty-three participants completed the questionnaire, of which most, especially advanced and intermediate participants, indicated the placenta as a valuable, accurate, and reproducible model. No differences were observed among the groups. CONCLUSIONS: The human placenta is an excellent tool for vascular microneurosurgery laboratory training. Color perfusion enhances the reliability of this model, which was validated by most surgeons, regardless of their experience.

Microneurosurgical management of giant intracranial aneurysms: Datasets of a twenty-year experience.

The data presented in this brief paper aims to summarize the overall results of 82 consecutive patients surgically treated over 20 years for a giant intracranial aneurysm (GIA) in the context of the endovascular era. Data were retrospectively collected from the database of two different tertiary referral Italian hospitals. A retrospective analysis of the patients' cohort was performed. Data are presented as they relate to the demographic and clinical aspects, the prevalence of GIAs according to anterior and posterior circulation, aneurysm angioarchitectural features, surgical treatment options, complications, outcome, and main microneurosurgical techniques required explicitly for GIAs, namely temporary clipping, aneurysm remodeling, thrombectomy, fragmentation, and bypass. Furthermore, data about the effects of implementing the flow-diverter/flow-disruptor on the surgical case volume over the years are also reported. The data presented herein are related to our previously published research article titled "Surgical Management of Giant Intracranial Aneurysms: Overall Results of a Large Series" (2020) [1].

Surgical Management of Giant Intracranial Aneurysms: Overall Results of a Large Series.

OBJECTIVE: To review and discuss surgical treatment options for giant intracranial aneurysms (GIAs), focusing on indications, technical aspects, and results, along with some illustrative cases. METHODS: We reviewed the data of 82 consecutive patients surgically managed between January 2000 and December 2019 for treatment of a GIA. RESULTS: Male sex and hemorrhage at presentation were prevalent. The average follow-up was 81.2 ± 45 months. The anterior circulation was involved in 76.8% of GIAs. If the GIA showed a clear neck, minimal atherosclerosis, or intrasaccular thrombosis, and ≤2 branches arising from the neck, it was reconstructed. This procedure was possible in 78% of cases. The technique also involved temporary clipping, remodeling, and thrombectomy, as well as fragmentation techniques. Angioarchitectural features other than these techniques underwent bypass and aneurysm trapping. Most bypasses were extracranial to intracranial and high flow. Flow capacity, collateral circulation, and availability of the donor vessel mainly affected the choice of the type of bypass. Overall, successful exclusion of the GIA was 91.4%. The need for retreatment and complication rate were 3.6% and 19.5%, respectively. A good overall outcome (modified Rankin Scale score 0-3) was achieved in 84.2% of patients, and mortality was 10%. CONCLUSIONS: Microneurosurgical techniques still maintain a significant role for most GIAs, with a high durability and acceptable rate of morbidity and mortality. Clip reconstruction is the first-line surgical treatment option, whereas bypass is indicated in cases of planned or unplanned sacrifice of the parent artery to prevent long-term ischemic complications.

Targeting of renin-angiotensin system in COVID-19 patients affected by stroke: Emerging concerns about detrimental vs. benefit effect.

OBJECTIVE: The present short report summarizes some clinical characteristics of six patients affected by stroke while being on angiotensin-converting enzyme (ACE)2 inhibitors and angiotensin II receptor blockers (ARBs) before and during COVID-19. METHODS: Medical charts and images of six patients affected by stroke while being on ACE-Is and ARBs therapy before and during COVID-19 outbreak in Lombardy region, Italy, were reviewed. RESULTS: Three patients had a dural sinus thrombosis, whereas the remaining suffered by an arterial ischemia, which was a middle cerebral artery occlusion in one case, and a posterior-inferior cerebellar artery occlusion in the remaining two. All patients showed clinical features typical of SARS-CoV-2 infection and positive chest CT scan, and were treated with ACE-Is as needed. Hypercoagulability panel was negative in any case. A recovery was achieved in all cases, although in a variable manner. CONCLUSIONS: Whether or not and in which manner the pharmacomodulation of the renin-angiotensin system may had affect the clinical course of the reported six COVID-19 patients affected by stroke has to be still clarified. An urgent need of randomized clinical trials aimed to assess the safety profile and neuroprotective properties of ACE-Is and ARBs in COVID-19 patients diagnosed with stroke does exists.

The Interhemispheric Transgenual Approach for Microsurgical Removal of Third Ventricle Colloid Cysts. Technical Note.

BACKGROUND: Colloid cysts of the third ventricle are rare benign lesions, which amount to approximately 1% of all intracranial tumors. Because these lesions grow predominantly in the anterior aspect of the third ventricle, they may cause the occlusion of the foramina of Monro, generating obstructive hydrocephalus. Surgery is mandatory in cases of large cysts and/or in symptomatic patients. Among the different surgical strategies described in colloid cysts surgery, the microsurgical transcallosal approach still constitutes the procedure of choice in many centers. In this study, we describe a modified microsurgical transcallosal approach, the interhemispheric transgenual approach, in a series of 13 consecutive patients operated on for colloid cysts of the third ventricle. METHODS: All the procedures were performed by the senior author (V.E.) at Neuromed Institute of Pozzilli (Is, Italy). The operative procedure is described in its various steps, illustrating the differences and potential advantages compared with the traditional microsurgical transcallosal approach. RESULTS: No surgical complications or new-onset neurologic deficits were observed in the postoperative period. The postoperative magnetic resonance imaging confirmed in all cases complete lesion removal without any sign of parenchymal damage. No lesion recurrence or need for permanent cerebrospinal fluid diversion was detected in the patients of this series during the follow-up period. CONCLUSIONS: In our experience, the interhemispheric transgenual approach has been effective in providing complete colloid cyst removal with minimal risk of vascular and parenchymal damage. Further studies are required to confirm its efficacy in improving the overall outcome of the microsurgical transcallosal approach.

Mild head trauma in elderly patients: experience of an emergency department.

INTRODUCTION: We evaluated the risk profile of elderly patients who came to the emergency department for mild head trauma. The primary goal was to determine the difference in the incidence of posttraumatic intracranial hemorrhage (ICH) after minor head injury (MHI). The secondary objective was to assess worse outcome, such as: hospitalization rate, rate of re-admission, need of neurosurgery. We also assess the admission process times and length of hospital stay. The ultimate goal was to optimize the diagnostic-observational management of minor head trauma in elderly patients. MATERIAL AND METHODS: We evaluated all patients with MHI who came to our emergency department during 2017 and 2018. All patients underwent computed tomography. RESULTS: We enrolled 2325 patients, of whom 1094 were 75 years of age or older. The population was divided into two categories according to age: The "elderly population" was 75 or older, and the younger patients were younger than 75. The elderly population, in comparison with the younger patients, had a higher rate of ICH (12.1% versus 5.1%), a higher hospitalization rate (11.7% versus 5.5%), and a higher rate of readmission within 30 days (6.8% versus 3.2%). The elderly population also had longer admission process times (8 h, 25 min, versus 4 h, 09 min) and longer lengths of hospital stay (9 h, 41 min, versus 5 h, 29 min). Of the younger patients, 92% (versus 41% of the elderly population) did not take any drugs, 6% (versus 39%) were receiving antiplatelet therapy, 1% (versus 13%) took vitamin K antagonists, and 1% (versus 7%) took oral direct-acting anticoagulants. Logistic regression models revealed that a 1-year increase in age raised the risk of bleeding by 2% on average; this finding was statistically significant (odds ratio [OR], 1023/year, p < 0.001). The rate of ICH increased significantly after the age of 75, by 180% (OR, 2.82; p < 0.001). CONCLUSIONS: These data suggest that age is an independent risk factor for ICH, whereby the age of 75 entails a 180% increase in the risk of bleeding.