Improving mixed-reality neuronavigation with blue-green light: a comparative multimodal laboratory study.

OBJECTIVE: This study aimed to rigorously assess the accuracy of mixed-reality neuronavigation (MRN) in comparison with magnetic neuronavigation (MN) through a comprehensive phantom-based experiment. It introduces a novel dimension by examining the influence of blue-green light (BGL) on MRN accuracy, a previously unexplored avenue in this domain. METHODS: Twenty-nine phantoms, each meticulously marked with 5-6 fiducials, underwent CT scans as part of the navigation protocol. A 3D model was then superimposed onto a 3D-printed plaster skull using a semiautomatic registration process. The study meticulously evaluated the accuracy of both navigation techniques by pinpointing specific markers on the plaster surface. Precise measurements were then taken using digital calipers, with navigation conducted under three distinct lighting conditions: indirect white light (referred to as no light [NL]), direct white light (WL), and BGL. The research enlisted two operators with distinct levels of experience, one senior and one junior, to ensure a comprehensive analysis. The study was structured into two distinct experiments (experiment 1 [MN] and experiment 2 [MRN]) conducted by the two operators. Data analysis focused on calculating average and median values within subgroups, considering variables such as the type of lighting, precision, and recording time. RESULTS: In experiment 1, no statistically significant differences emerged between the two operators. However, in experiment 2, notable disparities became apparent, with the senior operator recording longer times but achieving higher precision. Most significantly, BGL consistently demonstrated a capacity to enhance accuracy in MRN across both experiments. CONCLUSIONS: This study demonstrated the substantial positive influence of BGL on MRN accuracy, providing profound implications for the design and implementation of mixed-reality systems. It also emphasized that integrating BGL into mixed-reality environments could profoundly improve user experience and performance. Further research is essential to validate these findings in real-world settings and explore the broader potential of BGL in a variety of mixed-reality applications.

Use of BoneScalpel Ultrasonic Bone Dissector in Anterior Clinoidectomy and Posterior Fossa Surgery: Technical Note.

BackgroundFirst popularized by Dolenc, anterior clinoidectomies were performed with rongeurs, before the adoption of modern high-speed drills. We describe a novel application of the piezoelectric BoneScalpel™ in anterior skull base and posterior fossa surgeries. In the literature, to date, there are no mentions of anterior clinoidectomies performed with piezosurgical devices.MethodsWe reported a total of 12 patients, 8 affected by posterior fossa tumors and 4 treated for anterior skull base oncologic and vascular pathologies. This study aims to assess the safety and efficacy of the piezoelectric osteotomy in skull base and posterior fossa surgeries. In all patients, an ultrasonic bone dissector (BoneScalpel™ - Misonix) was used to perform the anterior clinoidectomy (AC) and craniotomy.ResultsA successful clinoidectomy was performed in 4 out of 12 patients (33.3%). We did not notice any heat damage to the surrounding soft tissue in critical areas such as paraclinoid structures. We documented only one durotomy in an oncologic patient, while no lesions of SSS or TS were detected.We recorded only a slightly increased surgery duration in the PIEZOSURGERY® and BoneScalpel™ group, compared to standard surgery with an osteotome to perform craniotomies, but no time difference in performing the clinoidectomy between BoneScalpel™ and a conventional high-speed drill.ConclusionWe report the first experience with piezosurgery for anterior clinoidectomy. There is no time difference in performing the clinoidectomy between BoneScalpel™ and a conventional high-speed drill, and this is an undoubted advantage in critical contexts such as clinoid-paraclinoid surgeries, where the risk of dural sinuses tears is common.

Multilevel Corpectomy for Subaxial Cervical Spondylodiscitis: Literature Review and Role of Navigation, Intraoperative Imaging and Augmented Reality.

BACKGROUND: Subaxial cervical spine spondylodiscitis represents a real challenge in spine surgery. In later stages multiple spinal metamers can the interested by the pathological infection and the alteration of the spinal stability leading to spinal deformity. There is scant literature on subaxial cervical spondylodiscitis management and especially on ≥three-level cervical corpectomies. The authors conducted a literature search on this specific topic and presented an emblematic case of a patient treated with circumferential cervical fixation and four-level cervicothoracic corpectomy. MATERIALS AND METHODS: A comprehensive literature review was performed using the combined Medical Subject Headings (MeSH) terms (multilevel) AND (sub axial spine OR cervical spine) AND (spine osteomyelitis OR spinal osteomyelitis), to search in the PubMed and Scopus databases. Our case was also included in this literature review. From our literature search the authors selected 13 papers, eight were excluded because they did not match our inclusion criteria (the involvement of only one or two levels, or did not perform corpectomy, discectomy, or cervical spine localization). The authors also presented a 71-year-old patient, in poor general clinical status who underwent several cage repositioning, with a final four-level corpectomy (C5, C6, C7, and T1), expandable C5-T1 cage positioning and C4-T2 anterior plating performed merging augmented reality, neuronavigation and intraoperative imaging. RESULTS: This systematic review included 28 patients treated with ≥ three-level corpectomy (11 patients with three-level corpectomy, 15 patients with four-level corpectomy, and 2 patients with six-level corpectomy), 6 women, 5 men, and 17 not reported specifically, with a mean age of 55.9 years (range: 44-72 years). The combined anterior and posterior approach was taken in all but one case, which was treated with the anterior approach only. In one case of six-level cervicothoracic corpectomy, sternotomy was necessary. All reported patients recovered after surgery, except one who died after nosocomial pneumonia. No major intraoperative complications were reported. Usual postoperative complications include wound hematoma, pneumonia, subsidence, epidural hematoma, dural leakage, dysphagia, soft tissue swelling. The mean follow-up time was 31.9 months (range: 8-110 months). CONCLUSION: According to the literature search performed by the authors, multilevel corpectomies for cervical spinal osteomyelitis is a safe and effective complex surgical procedure, even in extended procedures involving up to six levels or those at the cervicothoracic junction. The use multimodal navigation merging intraoperative imaging acquisition, navigation, and augmented reality may provide useful information during implant positioning in complex and altered anatomy and for assessing the best final result.

Chronic encapsulated intracerebral hematomas: a systematic review.

BACKGROUND: Chronic encapsulated intracerebral hematoma (CEICH) is a rare type of intracerebral hematoma (ICH) with peculiar radiological features and presenting as subtle slow-growing lesion exerting mass effect. We performed a systematic review of the literature focused on diagnosis and management of patients affected by CEICH. MATERIAL AND METHODS: A literature search according to the PRISMA statement was conducted using PubMed and Scopus databases and pertinent Mesh terms. All papers that reported intraventricular CEICH, or CEICH cases treated conservatively or by CT-guided needle aspiration were not included in this study. A total of 40 papers were included in this review, with 58 patients (38 males and 20 females) and a mean age of 41.44 ± 20.05 years (range 1-80). RESULTS: Neurological symptoms of onset include those related to an increase in intracranial pressure (ICP) in 28/58 cases (48.2%), seizures in 17/58 cases (29.3%), motor deficits in 14/58 cases (24.1%). The most frequent localization is atypical in 45/58 cases (77.6%). Surgical approach is not specified in 21/58 cases (36.2%), craniotomy was performed in 31/58 cases (53.4%), craniectomy in 5/58 cases (8.6%) and only in one case (1.7%) an endoscopic approach was performed. CEICH are usually located in an atypical site. CONCLUSIONS: There is not an association with anticoagulants and antiplatelets intake. Arteriovenous malformation is the most frequent cause. Surgery is suggested, and craniotomy is the most used approach even if further investigation should be directed to analyze the efficacy of endoscopic approach of these lesions, which may show favorable outcome.

Vertebrobasilar Dolichoectasia, Hypoplastic Third Ventricle, and Related Biventricular Hydrocephalus: Case Report and Review of the Literature.

BACKGROUND: Vertebrobasilar dolichoectasia (VBDE) is defined as a symptomatic dilatation and tortuosity of the vertebrobasilar arteries. The risk of hydrocephalus development is due to direct compression of the third ventricle outflow or brainstem compression and related aqueduct stenosis. We present an uncommon case of a patient with symptomatic VBDE with the uniqueness of a hypoplastic third ventricle associated with biventricular hydrocephalus. A literature review concerning diagnosis and management of patients affected by biventricular hydrocephalus caused by VBDE was also performed. CASE ILLUSTRATION: We report a case of a 54-year-old man who presented with headache, ideomotor apraxia, and gait disorder. A head computed tomography (CT) scan showed a biventricular hydrocephalus and a subsequent CT angiography documented the presence of a VBDE compressing the anterior part of the third ventricle that also appeared hypoplastic. The patient also presented a clinical history of arterial hypertension for which he was given a proper pharmacologic treatment with symptom relief. A surgical treatment of ventriculoperitoneal shunt along with endoscopic septostomy was proposed, but the patient refused, probably due to the slightly positive response to medical treatment. CONCLUSIONS: The natural clinical history of patients affected by VBDE is unfavorable with 7.8 years of median survival. The therapeutic strategy is usually conservative and the role of antiplatelets or oral anticoagulants is still debated. In selected patients, ventriculoperitoneal shunt to resolve intracranial hypertension caused by biventricular hydrocephalus is the most effective treatment. In our opinion, chronic third ventricle compression could lead to anatomic-pathologic alterations like the third ventricle hypoplasia documented in our report.

Diffuse cerebral angiomatosis associated to basilar apex aneurysm.

BACKGROUND: Diffuse cerebral angiomatosis (DCA) is a diffuse infiltration of normal brain by complex vascular structures. It differs from arteriovenous malformations (AVMs) that are composed of a nidus of vessels through which arteriovenous shunting occurs without interposed functional brain parenchyma. A rare subgroup of AVMs is diffuse with no recognizable nidus with functional neuronal tissue interspersed within the malformed vessels. We present a rare association of DCA and cerebral arterial aneurysm, which dramatically influenced the patient's prognosis. CASE DESCRIPTION: A 43-year-old male patient with right hemispheric diffuse cerebral angiomatosis presented with a ruptured basilar tip aneurysm that was successfully embolised. Unfortunately, the patient developed a locked-in syndrome. CONCLUSION: The present report shows a possible association between diffuse cerebral angiomatosis and cerebral aneurysms, but this association appears to be less strong than it is with other AVMs.

The one-step edge-to-edge technique in ventriculoperitoneal shunt.

BACKGROUND: Subcutaneous tunneling of the distal catheter is a potentially risky part of ventriculoperitoneal shunt (VPS) insertion. We describe our institutional experience with a simple trick to improve functional and aesthetic results in VPS by reducing the distal catheter tunneling to a single passage. MATERIALS AND METHODS: The one-step edge-to-edge technique has been performed in our institution over 14 years in 46 patients with a mean age of 63. 27 were female (58.7%). 7 patients suffered from post-traumatic hydrocephalus, 6 from normal pressure hydrocephalus, 15 from obstructive hydrocephalus and 18 from hydrocephalus secondary to subarachnoid hemorrhage. Operative blood loss varied from 20 to 40 cc. RESULTS: No complication related to the modified tunneling technique were described except a transitory peripheral VII nerve palsy (2.2%). The absence of middle skin incision is appreciated by the patient, especially in young females that not presented scars at the level of the neckline. CONCLUSION: Our technique is the first report of one step tunneling in adults. It reduces distal catheter tunneling time in VPS simplifying the procedure to a single step and using a simple reproducible trick.

Extra-Neural Metastases From Primary Intracranial Ependymomas: A Systematic Review.

Background: Primary intracranial ependymomas (IE) are rare brain tumors rarely metastasizing outside the central nervous system. We systematically reviewed the literature on extra-neural metastases from primary IEs. Methods: PubMed, Scopus, Web-of-Science, and Cochrane were searched following the PRISMA guidelines to include studies of extra-neural metastases from primary IEs. Clinical features, management strategies, and survival were analyzed. Results: We collected 48 patients from 43 studies. Median age was 13 years (range, 2-65). Primary IEs were frequently located in the parietal (22.9%) and frontal (16.7%) lobes, and mostly treated with resection (95.8%) and/or radiotherapy (62.5%). Most IEs were of grade-III (79.1%), and few of grade-I (6.3%) or grade-II (14.6%). 45 patients experienced intracranial recurrences, mostly treated with resection (86.7%), radiotherapy (60%), and/or chemotherapy (24.4%). Median time-interval from primary IEs was 28 months (range, 0-140). Most extra-neural metastases were diagnosed at imaging (37.5%) or autopsy (35.4%). Extra-neural metastases were multifocal in 38 patients (79.1%), mostly involving cervical or hilar lymph-nodes (66.7%), lung/pleura (47.9%), and/or scalp (29.1%). Surgical resection (31.3%), chemotherapy (31.3%) and locoregional radiotherapy (18.8%) were the most common treatments for extra-neural metastases, but 28 (58.3%) patients were not treated. At last follow-up, 37 patients died with median overall-survivals from primary IEs of 36 months (range, 1-239), and from extra-neural metastases of 3 months (range, 0.1-36). Overall-survival was significantly longer in patients with grade-I and II IEs (P=0.040). Conclusion: Extra-neural metastases from primary IEs are rare, but mostly occur at later disease stages. Multidisciplinary management strategies should be intended mostly for palliation.

Spontaneous intracerebral pseudoaneurysm rupture and meningiomatosis: A case report and review of the literature.

BACKGROUND: We report the first case of a spontaneous ruptured anterior cerebral artery pseudoaneurysm in a patient affected by meningiomatosis. CASE DESCRIPTION: A 71-year-old female patient was admitted to our emergency department after acute loss of consciousness. An urgent head CT scan showed third ventricle hemorrhage and a giant extra-axial tumor with associated peritumoral bleeding. A second, smaller, and right-sided tumor was detected at the posterior third of the superior sagittal sinus, indicative of meningiomatosis diagnosis. A following CT angiogram showed an hypervascularized lesion at the right frontal convexity and a ruptured A2 pseudoaneurysm. Tumor removal was performed through right frontal craniotomy. After the initial debulking and removal of the peritumoral hemorrhage, the A2 segment associated with the bleeding pseudoaneurysm was surgically coagulated. CONCLUSION: We report the unique occurrence of two relatively rare neurological entities: meningiomatosis and intracranial pseudoaneurysm. In our experience, their simultaneous and acute presentation is associated to poor prognosis.

Posterior epidural intervertebral disc migration and sequestration: A systematic review.

Posterior epidural intervertebral disc migration and sequestration (PEIMS) is a rare and debilitating complication of degenerative disc disease. Radiological differential diagnosis is often challenging, complicating the accurate planning of appropriate treatment strategies. We systematically reviewed the literature on PEIMS, focusing on clinical-radiological features and available treatments. PubMed, Scopus, Web of Science, and Cochrane were searched to include studies reporting clinical data of patients with PEIMS. Clinical characteristics, treatment strategies, and functional outcomes were analyzed. We included 82 studies comprising 157 patients. Median age was 54 years (range, 19-91). PEIMSs occurred spontaneously (49.7%) or acutely in patients with underlying progressive degenerative disc disease (50.3%). The most common symptoms were lower-back pain (77.1%) and radiculopathy (66.2%), mainly involving the L5 nerve root (43.8%). PEIMSs were mostly detected at MRI (93%) and/or CT (7%), frequently located in the lumbar spine (81.5%). Median maximum PEIMS diameter was 2.4 cm (range, 1.2-5.0). Surgical debulking was completed in 150 patients (95.5%), sometimes coupled with decompressive laminectomy (65%) or hemilaminectomy (19.1%). Median follow-up time was 3 months (range, 0.5-36.0). Post-treatment symptomatic improvement was reported in 153 patients (97.5%), with total recovery in 118 (75.2%). All 7 patients (4.5%) who received conservative non-surgical management had total clinical recovery at ≤ 3 months follow-ups. PEIMS is a challenging entity that may severely quality-of-life in patients with degenerative disc disease. Surgical removal represents the gold standard to improve patient's functional status. Spine fusion and conservative strategies proved to be effective in some cases.

Thoracic Spinal Angiolipomas: A Systematic Review.

BACKGROUND: Spinal angiolipomas (SAs) are rare, benign tumors, representing 0.0004 to 1.2% of angiolipomas, usually located at the extradural and posterior thoracic level, with multimetameric extension. METHODS: A systematic literature review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. The authors searched on PubMed and Scopus databases for published articles with the Mesh term "spinal angiolipoma" and pertinent associations. Language restriction to English papers was applied. The authors also reported three emblematic cases of patients who underwent surgical resection of spindle-shaped (type IA) and dumbbell-shaped (type II) SAs between 2014 and 2020. RESULTS: Of the 256 retrieved articles, 33 were included in the meta-analysis. These 33 studies, together with our 3 reported cases, included a total of 60 patients, 36 females (60%) and 24 males (40%), with a mean age of 53.12 ± 12.82 years (range: 12-77 years).T5 was the most represented level (22 patients). Usually, the localization of SA was extradural, with 53 patients suffering from spindle-shaped type IA SA (88.3%) and 7 patients from dumbbell-shaped type II SA (11.6%). Almost all patients underwent laminectomy (78.3%) and presented a full recovery of motor deficits (85%). Gross total removal (GTR) was performed in 93.3% of patients. The mean follow-up was of 22.71 ± 21.45 months (range: 2-80 months). There was no documented recurrence at follow-up magnetic resonance imaging in any of the patients. CONCLUSIONS: SAs are rare, benign tumors with a great vascular component that presents a favorable outcome. GTR is the gold standard treatment and usually an adjuvant therapy is not required. Even infiltrative lesions, which are more complex, can be treated successfully with a good prognosis. Dumbbell-shaped SAs must be differentiated from schwannomas and meningiomas, and require different surgical techniques, given the profuse bleeding associated with the attempt of debulking. En block resection is the key to treat these common benign tumors with acceptable blood loss.

A Review of Remote Intracerebral Hemorrhage after Chronic Subdural Hematoma Evacuation.

BACKGROUND: Remote intracerebral hemorrhage (RICH) is a severe complication following chronic subdural hematoma (cSDH) drainage, and only case reports and small case series have been reported to date. The authors present an emblematic patient affected by RICH following cSDH drainage. A systematic review of the literature on diagnosis and management of patients affected by RICH following cSDH evacuation has also been performed. METHODS: A literature search according to the PRISMA statement was conducted using PubMed and Scopus databases with the following Mesh terms: [(remote) AND (intracerebral hemorrhage or cerebral hematoma or cerebral infarction or cerebellar hemorrhage or cerebellar hematoma or cerebellar infarction) AND (chronic subdural hematoma)]. RESULTS: The literature search yielded 35 results, and 25 articles met our inclusion criteria: 22 articles were case reports and 3 were case series including three to six patients. Overall, 37 patients were included in the study. Age was reported in all 37 patients, 26 males (70.3%) and 11 females (29.7%), with a male-to-female ratio of 2.4:1. The mean age at diagnosis was 64.6 years (range: 0.25-86 years). Only in 5 cases (13.5%) did the ICH occur contralaterally to the previously drained cSDH. The rapidity of drainage can lead to several types of intracranial hemorrhages, caused by a too rapid change in the cerebral blood flow (CBF) and/or tears of bridging veins. The average time interval between cSDH drainage and neurologic deterioration was 71.05 hours (range: 0-192 hours). CONCLUSIONS: RICH following cSDH represents a rare occurrence and a serious complication, associated with elevated morbidity. Careful monitoring of drain speed after cSDH evacuation surgery is recommended, and minimally invasive techniques such as twist drill craniostomy are suggested, especially for massive cSDHs.

Minimally invasive percutaneous anterior odontoid screw fixation: institutional experience with a simple and effective technique.

BACKGROUND: The aim of this paper was to show a novel modified technique to perform minimally invasive anterior odontoid screw fixation. METHODS: Twenty-nine patients with a mean age of 45 years were treated with a modified percutaneous anterior odontoid screw fixation. All patients were affected by type II or rostral shallow type III odontoid fractures. A modified guide tube was used in all these patients, with reduction of soft tissue dissection for percutaneous approach. RESULTS: There were no complications related to the modified technique. Good results and optimal screw placement were achieved in 28 out of 29 patients. Only in 1 patient we observed, after mobilization, screw displacement, probably due to severe osteoporosis. CONCLUSIONS: In our opinion, this modified percutaneous minimally invasive technique for anterior odontoid screw fixation, along with the use of a soft tissue dilator not fixed to the spine, has not yet been reported in literature and is strongly recommended to reduce invasiveness of odontoid screw placement.

Largest neurosurgical social media group and its impact on communication and research.

BACKGROUND: The use of social media to communicate and disseminate knowledge has increased exponentially, especially in the field of neurosurgery. 'Neurosurgery cocktail' (NC) was developed by a group of young neurosurgeons as a means of sharing didactic materials and clinical experiences via social media. It connects 35.000 neurosurgeons worldwide on multiple platforms, primarily Facebook and Twitter. Given the rising utilization of social media in neurosurgery, the popularity of NC has also increased since its inception. In this study, the authors surveyed the social media analytics of NC for both Facebook and Twitter. Besides, we reviewed the literature on the use of social media in neurosurgery. METHODS: Facebook and Twitter metrics were extracted through each respective platform's analytics tools from December 2020 (earliest available date for data analysis) through January 2021. A literature search was conducted using PubMed (MEDLINE) and Scopus databases. RESULTS: On Facebook, as of January 2021, the group had a total of 25.590 members (87.6% male), most commonly (29%) between 35 and 44 years of age with over 100 countries were represented. As of January 2021, they had amassed 6457 followers on Twitter. During the last 28 d between December 2020 and January 2021, the account published 65 tweets that garnered a total of 196,900 impressions. Twelve articles were identified in our literature review on the use of social media within the neurosurgical community. CONCLUSIONS: NC is one of the most widely utilized neurosurgical social media resources available. Sharing knowledge has been broadened thanks to the recent social media evolution, and NC has become a leading player in disseminating neurosurgical knowledge.

Use of Gelatin-thrombin Hemostatic Matrix for Control of Ruptured Cerebral Aneurysm.

BACKGROUND: The use of thrombin-based hemostatic agents (TBHAs) has become common practice in most neurosurgical procedures, both cranial and spinal. METHODS: We present the case of a 40-year-old woman who was referred to our institution with intense headache and Fisher grade 3 subarachnoid hemorrhage (SAH) mainly at the level of the right sylvian fissure, caused by a 5.71-mm right middle cerebral artery (MCA) bifurcation aneurysm, with hourglass morphology and a bleb on the bottom. Cerebral angiography demonstrated aneurysm enlargement, compared with the prior angiographic computerized tomography scan. RESULTS: A right pterional craniotomy was performed. After initial arachnoid dissection to get proximal vascular control, but before we obtained it, we witnessed profuse bleeding from the aneurysm. Floseal, a gelatin-thrombin matrix sealant, was sprayed over the breach of the aneurysm, and cottonoids were gently pressed with a self-retaining spatula, stopping the hemorrhage. After that, we obtained proximal control with an extradural clinoidectomy and temporary clipping of the right internal carotid artery (ICA) and MCA. Finally, aneurysm dissection and final clipping were performed with the application of two clips. The postoperative course was uneventful, and the patient was discharged on postoperative day 10. CONCLUSION: Intraoperative aneurysm rupture (IAR) is a dangerous event that carries great risks-even death. Proper use of TBHAs is a useful and safe way to stop the bleeding, take a deep breath, and achieve proximal vascular control. To the best of our knowledge, this is the first report of the use of TBHA during aneurysm clipping.

Diamond-Shaped Mini-Craniotomy: A New Concept in Neurosurgery.

BACKGROUND: We describe, step by step, a modified, less invasive, diamond-shaped mini-craniotomy that optimizes dural opening and can be performed in elderly patients affected by acute subdural or intracerebral hematomas, in therapy with antiplatelets or anticoagulants. METHODS: We retrospectively analyzed the clinical records of 67 patients (mean age of 78.5 years) treated in our institution, during a period of 10 years, with this novel diamond-shaped craniotomy. Seventeen patients were treated for intracerebral hemorrhage and 50 patients for acute subdural hematomas. All the patients were in therapy with antiplatelets or anticoagulants. RESULTS: Approach-related complications were not detected. Ten of 67 patients (14.9%) presented temporal muscle atrophy; there was no scar deformity, paresthesia, hyperalgesia, or ramus frontalis palsy around the scalp incision. Thirty-day mortality was 22%. The mean follow-up was 1.3 years. One-month postoperative brain computed tomography scans showed a satisfactory hematoma evacuation in 57 of 67 patients (85%). CONCLUSIONS: The diamond-shaped mini-craniotomy for acute subdural and intracerebral hematomas is safe and effective, and it should be considered as an alternative to traditional approaches, particularly in elderly patients.

Spontaneous sacral fracture with associated acrometastasis of the hand.

BACKGROUND: Acrometastases, secondary tumors affecting oncological patients with systemic metastases, are associated with a poor prognosis. In rare cases, acrometastases may precede establishing the primary tumor diagnosis. CASE DESCRIPTION: A 72-year-old female heavy smoker presented with low back pain, and right lower extremity sciatica/radiculopathy. X-rays, CT, MR, and PET-CT scans documented primary lung cancer with multi-organ metastases and accompanying pathological fractures involving the sacrum (S1) and right 4th digit. She underwent a S1 laminectomy and amputation of the distal phalanx of the right fourth finger. The histological examination documented a poorly differentiated pulmonary adenocarcinoma infiltrating bone and soft tissues in the respective locations. The patient was treated with a course of systemic immunotherapy (i.e. pembrolizumab). At 6-month follow-up, the patient is doing well and can stand and walk without pain. CONCLUSION: Spontaneous sacral fractures may be readily misdiagnosed as osteoporotic and/or traumatic lesions. However, in this case, the additional simultaneous presence of a lytic finger lesion raised the suspicion that these were both metastatic tumors. Such acrometastases, as in this case attributed to a lung primary, may indeed involve the spine.

Primary Extracranial Meningiomas of the Head and Neck.

Meningiomas represent the most common benign histological tumor of the central nervous system. Usually, meningiomas are intracranial, showing a typical dural tail sign on brain MRI with Gadolinium, but occasionally they can infiltrate the skull or be sited extracranially. We present a systematic review of the literature on extracranial meningiomas of the head and neck, along with an emblematic case of primary extracranial meningioma (PEM), which provides further insights into PEM management. A literature search according to the PRISMA statement was conducted from 1979 to June 2021 using PubMed, Web of Science, Google Scholar, and Scopus databases, searching for relevant Mesh terms (primary extracranial meningioma) AND (head OR neck). Data for all patients were recorded when available, including age, sex, localization, histological grading, treatment, possible recurrence, and outcome. A total of 83 published studies were identified through PubMed, Google Scholar, and Scopus databases, together with additional references list searches from 1979 to date. A total of 49 papers were excluded, and 34 manuscripts were considered for this systematic review, including 213 patients. We also reported a case of a 45-year-old male with an extracranial neck psammomatous meningioma with sizes of 4 cm × 3 cm × 2 cm. Furthermore, whole-body 68Ga-DOTATOC PET/CT was performed, excluding tumor spread to other areas. Surgical resection of the tumor was accomplished, as well as skin flap reconstruction, obtaining radical removal and satisfying wound healing. PEMs could suggest an infiltrative and aggressive behavior, which has never found a histopathological correlation with a malignancy (low Ki-67, <5%). Whole-body 68Ga-DOTATOC PET/CT should be considered in the patient's global assessment. Surgical removal is a resolutive treatment, and the examination of frozen sections can confirm the benignity of the lesion, reducing the extension of the removal of healthy tissue surrounding the tumor.

Acrometastases to the Hand: A Systematic Review.

Background and Objectives: The term acrometastases (AM) refers to secondary lesions sited distally to the elbow and knee, representing 0.1% of all bony metastases. By frequency, pulmonary cancer and gastrointestinal and genitourinary tract neoplasms are the most responsible for the reported AM. Improvements in oncologic patient care favor an increase in the incidence of such rare cases. We performed a systematic review of acrometastases to the hand to provide further insight into the management of these fragile patients. We also present a peculiar case of simultaneous acrometastasis to the ring finger and pathological vertebral fracture. Material and Methods: A literature search according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) statement was conducted using the PubMed, Google Scholar, and Scopus databases in December 2020 on metastasis to the hand and wrist, from 1986 to 2020. MeSH terms included acrometastasis, carpal metastasis, hand metastasis, finger metastasis, phalangeal metastasis, and wrist metastasis. Results: In total, 215 studies reporting the follow-up of 247 patients were analyzed, with a median age of 62 years (range 10-91 years). Overall, 162 out of 247 patients were males (65.6%) and 85 were females (34.4%). The median reported follow-up was 5 months (range 0.5-39). The median time from primary tumor diagnosis to acrometastasis was 24 months (range 0.7-156). Acrometastases were located at the finger/phalanx (68.4%), carpal (14.2%), metacarpal (14.2%), or other sites (3.2%). The primary tumors were pulmonary in 91 patients (36.8%). The average interval from primary tumor diagnosis to acrometastasis varied according to the primary tumor type from 2 months (in patients with mesenchymal tumors) to 64.0 months (in patients with breast cancer). Conclusions: Acrometastases usually develop in the late stage of oncologic disease and are associated with short life expectancy. Their occurrence can no longer be considered rare; physicians should thus be updated on their surgical management and their impact on prognosis and survival.

Difficulty differentiating between a posterior extradural lumbar tumor versus sequestered disc even with gadolinum-enhanced MRI.

BACKGROUND: Differentiating between posterior extradural tumors versus sequestered lumbar disc herniations may be difficult even utilizing contrast-enhanced MR scans. CASE DESCRIPTION: A 49-year-old male acutely presented with an incomplete cauda equine syndrome. When the MRI showed a L4-L5 posterior extradural lesion that enhanced with gadolinium, an urgent left hemilaminectomy was performed. The lesion proved to be a sequestrated disc herniation rather than a tumor. Notably, postoperatively the patient almost completely recovered after 6-month follow-up. CONCLUSION: Even on contrast-enhanced MRI studies, posterior extradural sequestered lumbar disc herniations may mimic tumors.