Multinodular plexiform tumors of major peripheral nerves: A practical overview.

BACKGROUND AND AIMS: Multinodular/plexiform schwannomas and neurofibromas of major nerves are rare: before surgery, differential diagnosis among these two uncommon variants is challenging. For both forms, surgical removal is recommended in case of progressive growth and worsening of neurological symptoms. Surgery has a higher risk of neurological damage than conventional schwannomas or neurofibromas. In literature, a comparison among these rare tumors is usually limited to the pathological aspect while specific surgical and clinical management indications are lacking. Cutaneous tumors of both forms arising from terminal peripheral nerves' branches might be treated by plastic surgeons while tumors of major nerves remain under neurosurgical competence. Here we report our recent neurosurgical experience on the matter, to furnish useful suggestions for the management of these tumors. METHOD: We analyzed the clinical, radiological, and pathological data in a consecutive case series of plexiform/multinodular nerve tumors operated at our institution in the last five years. RESULTS: In our series, neurofibroma type of plexiform tumors was more frequent than schwannoma type: two sporadic plexiform-multinodular schwannomas (patients 1, and 5) and three multinodular/plexiform Neurofibromatosis familial (Neurofibromatosis 1 / NF-1) (patients 2, 3, and 4). Surgery was complex when major nerves were involved. The early outcome appeared mostly related to the pre-surgical neurological conditions and histological grading. INTERPRETATION: Although sharing some features, multinodular-plexiform schwannomas and neurofibromas have consistent differences from the clinical, surgical and pathological points of view.

Intraventricular infusion test accuracy in predicting short- and long-term outcome of iNPH patients: a 10-year update of a three-decade experience at a single institution.

OBJECTIVE: In a previous work, we found that an Intracranial Elastance Index (IEI) ≥0.3 at ventricular infusion test had a high accuracy in predicting shunt response at 6 and 12 months in idiopathic normal pressure hydrocephalus (iNPH). The aim of this study was to verify the accuracy of IEI to predict response to shunt at both short- and long-term follow-up. METHODS: Retrospective evaluation of 64 patients undergoing ventriculo-peritoneal shunting for iNPH between 2006 and 2015 based on a positive ventricular infusion test (IEI≥0.3). Patients were classified according to Krauss scale and mRS preoperatively, at 1-year and at last follow-up. An improvement of at least one point at Krauss score or at mRS was considered as a good outcome; unchanged or worsened patients were grouped as poor outcome. RESULTS: Mean follow-up was 6.6 years. Improvement at Krauss scale was seen in 62.5% and 64.3% of patients at 1-year and last follow-up, respectively. Patients in good functional status (mRS≤2) increased from 25 in the preoperative period to 57% at both 1-year and last follow-up. IEI was significantly associated with Krauss (p=0.041) and mRS (p=0.036) outcome at last follow-up. Patients with worse preoperative Krauss and mRS had higher chance to improve but higher overall scores after treatment. At ROC curves, IEI showed a good long-term prediction of change in mRS from first year to last follow-up. CONCLUSIONS: IEI≥0.3 predicts outcomes at both short- and long-term, with more than 50% of patients being able to look after themselves after 6 years from treatment.

Old Perched Facet Joint Syndrome: "The Always-Anterior Strategy." Report of Two Cases and Review of the Literature.

BACKGROUND: Perched facet joint syndrome is a common post-traumatic condition encountered at the level of subaxial cervical spine in acute settings but more rarely found in a chronic manner. We define this dislocation as old subaxial cervical facet dislocation (OSCFD) when adequate treatment is not established within 3 weeks after initial trauma. It is a clinical entity, moreover, associated with significant impact on neurologic functions such as nerve root or spine compression. Many factors are attributed to explain delayed diagnosis, such as living in a developing country, misreading or inadequate imaging, the presence of multiple injuries, or an absence of symptoms at the time of trauma. CASE DESCRIPTION: We report 2 typical examples of long-lasting OSCFD (up to 6 months), treated both by an anterior cervical approach but with 2 different surgical strategies, associated with similar subsequent clinical restoration and neuroradiologic realignment. We also review the related literature regarding the mechanisms underlying this unusual observation and varied surgical strategies adopted, finally explaining the reasons for our choosing the always-anterior strategy. CONCLUSIONS: In OSCFD, performing a vertebral canal decompression and realignment of the cervical spine column is crucial. More options are purposed to treat this challenging condition, and more of them could be complicated by time-consuming resetting in the operating room, prolonged anesthesiologic procedures, and elevated risk of 360° instrumentation surgical maneuvers. The one-stage combined anterior-approach only (corpectomy or discectomy) is an effective, fast, and safe surgical strategy for treating OSCFD.

Extraforaminal Vertebral Artery Until C2 Transverse Foramen in Down Syndrome Patient Affected by Atlantoaxial Subluxation: First Observation and Review of Literature.

BACKGROUND: Patients with Down syndrome (DS) have an increased incidence of multisystem disorders, like cardiovascular, neurologic, gastrointestinal, respiratory, and musculoskeletal disorders. Craniovertebral junction instability is a common illness in DS patients, and they may often be affected by vertebral artery (VA) anomalies. CASE DESCRIPTION: In this paper we present neuroradiologic findings of a 34-year-old female patient affected by DS with atlantoaxial subluxation, scheduled for transoral decompression of C1-C2 and posterior occipitocervical fixation. The preoperative angio-computed tomography scan showed a peculiar anatomic variation in the entrance of the VA at the level of the C2 transverse foramen (TF). Normally, the segment of VA, named V2, becomes intraforaminal on average at the TF of C6. CONCLUSIONS: We reviewed the literature about the incidence of anatomic variations of the V2 segment in both the general population and the one affected by DS, and although numerous cases of anomalous course, none reported a C2 TF entry point. Ignoring such extremely rare anatomic variation during anterior, posterior, or lateral surgical approach to the cervical spine can lead to inadvertent injury and potentially serious complications like arterial dissection, thrombus, vascular spasm, fistula, pseudoaneurysm, cerebral ischemia, and death.

Bullough's Lesion: An Unexpected Diagnosis After the Resection of a Slowly Growing Osseous-Like Retroauricular Bump-Case Report and Review of the Literature.

We describe the case of a 33-year-old woman with a history of over 15 years of a slow growing firm osseous-like right retroauricular mass. Surgical resection was easily performed using a sharp technique, because of a clear cleavage plane. The histologic diagnosis was a rare, unexpected, protuberant fibro-osseous lesion named "Bullough lesion." Only few cases of this benign pathologic entity have been described in English literature. Clinical differential diagnosis must be done with osteoma, periosteal chondroma, and other fibro-osseous lesions such as fibrodysplasia and ossifying fibroma. Because of the paucity of data, the natural history of this lesion is unknown and serial clinical and radiological follow-up is advised.

Surgical Management of Intracranial Giant Epidermoid Cysts in Adult: A Case-Based Update.

Epidermoid cysts (ECs) are benign and slow-growing lesions that account for about 0.2%-2% of all intracranial tumors. Symptoms appear slowly and tumors may have already grown to giant proportions when patients receive their first diagnosis. The optimal treatment for ECs is surgical removal, which includes the total resection of the entire capsule of the lesion in order to minimize the risk of malignant transformation associated with partial removal. However, considering the giant size that the ECs can reach at the time of the diagnosis, and their adherence to the surrounding structures, the risks and benefits of total versus subtotal resections in the short- and long-term patients' outcome are still under debate. Here, we report a case of an extensive giant EC and offer a discussion of its characteristics, surgical management, and postoperative outcome, taking a cue to argue about the recent literature based in the latest case studies.

Incidental intraoperative diagnosis of Mycobacterium abscessus meningeal infection: a case report and review of the literature.

PURPOSE: Mycobacterium abscessus, and rapidly growing mycobacteria in general, are rare but increasing causes of central nervous system (CNS) infections. The aim of this study is to highlight the importance of considering these microorganism in the differential diagnosis of CNS infections, obtaining a prompt diagnosis, and improving clinical outcomes. METHODS: Case report and literature review. RESULTS: We report a case of meningeal infection in a patient who underwent decompressive craniectomy after a craniofacial trauma. The diagnosis was made analyzing a sample obtained during a second operation of cranioplasty. A regimen of amikacin, clarithromycin, and imipenem/cilastatin was started. In the following days, the patient experienced a variety of side effects. So, first clarithromycin was replaced with linezolid, then amikacin was stopped and cefoxitin added to the therapy and at the end all the antibiotics were withdrawn. The patient was discharged in good conditions and a clinical interdisciplinary follow-up was started. After 12 months, the patient is still doing well. After a literature analysis, 15 cases of M. abscessus CNS infections were identified. Various modes of acquisition, underlying disease and therapeutic schemes were evident. CONCLUSIONS: Considering the results of the literature analysis and the increasing incidence of M. abscessus, all specialists involved in the management of CNS infection should be aware of the importance of atypical microorganisms in differential diagnosis.