Reflections upon the intrauterine repair of myelomeningocele.

The intrauterine repair of myelomeningocele presents certain advantages and has gained widespread acceptance. It significantly reduces the incidence of Chiari-2 anomalies and hydrocephalus, and it is thought to enhance the neurologic outcome. Nevertheless, several issues remain unsettled and there are no negligible disadvantages. After working with patients with myelomeningocele for 30 years, I thought about how we currently treat them. There are ethical, organizational, neurological, obstetrical, and postnatal aspects worth discussing.

Posterior fossa syndrome in a population of children and young adults with medulloblastoma: a retrospective, multicenter Italian study on incidence and pathophysiology in a histologically homogeneous and consecutive series of 136 patients.

INTRODUCTION: Posterior fossa syndrome (PFS) is a set of debilitating complications that can occur after surgery for posterior fossa tumors. This study aimed to assess the preoperative radiological and surgical risk factors for the onset of PFS in a histologically homogeneous population of children with medulloblastoma and compare it to a similar population of young adults. METHODS: Included patients underwent posterior fossa surgery for medulloblastoma at 11 Italian neurosurgical wards (2003-2019) and were referred to Fondazione IRCCS Istituto Nazionale dei Tumori in Milan (INT) for postoperative treatments. We collected patients' pre- and post-operative clinical, surgical and radiological data from the INT charts. To compare the distribution of variables, we used the Mann-Whitney and Fisher tests for continuous and categorical variables, respectively. RESULTS: 136 patients (109 children and 27 young adults) were included in the study. Among children, 29 (27%) developed PFS, and all of them had tumors at midline site with invasion of the fourth ventricle. Radiological evidence of involvement of the right superior (39% versus 12%; p = 0.011) or middle cerebellar peduncles (52% versus 18%; p = 0.002) seemed more common in children who developed PFS. Young adults showed an expected lower incidence of PFS (4 out of 27; 15%), that may be due to anatomical, physiological and oncological elements. CONCLUSIONS: This study confirmed some factors known to be associated with PFS onset and shed light on other debated issues. Our findings enhance an already hypothesized role of cerebellar language lateralization. The analysis of a population of young adults may shed more light on the often-neglected existence of PFS in non-pediatric patients.

Diagnosis and treatment of Chiari malformation type 1 in children: the International Consensus Document.

BACKGROUND: Chiari malformation type 1 (CM1) is a rare condition where agreed classification and treatment are still missing. The goal of this study is to achieve a consensus on the diagnosis and treatment of CM1 in children. METHODS: A multidisciplinary panel formulated 57 provisional statements based on a review of the literature. Thirty-four international experts (IE) participated in a Delphi study by independently rating each statement on a 4-point Likert scale ("strongly disagree," "disagree," "agree," "strongly agree"). Statements that were endorsed ("agree" or "strongly agree") by < 75% of raters were re-formulated, or new statements were added, and another Delphi round followed (up to a maximum of three). RESULTS: Thirty-five IE were contacted and 34 agreed to participate. A consensus was reached on 30/57 statements (52.6%) after round 1. Three statements were added, and one removed. After round 2, agreement was reached on 56/59 statements (94.9%). Finally, after round 3, which took place during the 2019 Chiari Consensus Conference (Milan, Italy), agreement was reached on 58/59 statements (98.3%) about four main sections (Definition and Classification, Planning, Surgery, Isolated Syringomyelia). Only one statement did not gain a consensus, which is the "definition of radiological failure 24 month post-surgery." CONCLUSIONS: The consensus document consists of 58 statements (24 on diagnosis, 34 on treatment), serving clinicians and researchers following children with CM1. There is a clear need for establishing an international network and registry and to promote collaborative studies to increase the evidence base and optimize the long-term care of this patient population.

Diagnosis and treatment of Chiari malformation and syringomyelia in adults: international consensus document.

BACKGROUND: Syringomyelia and Chiari malformation are classified as rare diseases on Orphanet, but international guidelines on diagnostic criteria and case definition are missing. AIM OF THE STUDY: to reach a consensus among international experts on controversial issues in diagnosis and treatment of Chiari 1 malformation and syringomyelia in adults. METHODS: A multidisciplinary panel of the Chiari and Syringomyelia Consortium (4 neurosurgeons, 2 neurologists, 1 neuroradiologist, 1 pediatric neurologist) appointed an international Jury of experts to elaborate a consensus document. After an evidence-based review and further discussions, 63 draft statements grouped in 4 domains (definition and classification/planning/surgery/isolated syringomyelia) were formulated. A Jury of 32 experts in the field of diagnosis and treatment of Chiari and syringomyelia and patient representatives were invited to take part in a three-round Delphi process. The Jury received a structured questionnaire containing the 63 statements, each to be voted on a 4-point Likert-type scale and commented. Statements with agreement <75% were revised and entered round 2. Round 3 was face-to-face, during the Chiari Consensus Conference (Milan, November 2019). RESULTS: Thirty-one out of 32 Jury members (6 neurologists, 4 neuroradiologists, 19 neurosurgeons, and 2 patient association representatives) participated in the consensus. After round 2, a consensus was reached on 57/63 statements (90.5%). The six difficult statements were revised and voted in round 3, and the whole set of statements was further discussed and approved. CONCLUSIONS: The consensus document consists of 63 statements which benefited from expert discussion and fine-tuning, serving clinicians and researchers following adults with Chiari and syringomyelia.

Surgical pathway proposal for severe paralytic scoliosis in adolescents with myelomeningocele.

PURPOSE: The increased life expectancy of patients with myelomeningocele led to the necessity of new management for addressing complex spine deformities with severe pelvic obliquity. Tethered cord release (TCR) and spinal fusion were described as treatment options. However, nowadays, the surgical strategy is not well defined and high rates of mechanical failures and complications are reported. Our aim was to propose a new two-stage surgical pathway to treat a selected group of severe myelomeningocele scoliosis. METHODS: This is a retrospective series of myelomeningocele scoliosis in paralytic adolescent patients treated with concurrent TCR and posterior spinal fusion (PSF), followed by delayed anterior fusion (ASF) through minimally invasive lateral approach. Inclusion criteria were as follows: evolutive scoliosis in tethered cord syndrome and paraplegia, main curve >70°, pelvic obliquity >20°, and age between 10 and 18 years. Clinical, surgical, and radiographic parameters were evaluated preoperatively and at a mean follow-up (FU) of 2.8 years. RESULTS: Six patients out of 58 met the inclusion criteria and were included in the study (mean age 12.3 years old). The mean curve and pelvic obliquity correction were 68.8% and 82%, respectively. No loss of correction was recorded at FU. One case of cerebrospinal fluid leakage requiring revision surgery was recorded. CONCLUSION: To the best of our knowledge, this is the first study proposing a two-stage surgical pathway for severe MMC spinopelvic deformity treatment. Concurrent TCR and PSF with delayed minimally invasive ASF permitted to minimize complications providing good fusion rates without loss of correction and implant failure.

Intracranial Dural Arteriovenous Fistulas: The Sinus and Non-Sinus Concept.

INTRODUCTION: Dural arteriovenous fistulas (dAVFs) account for 10-15% of all intracranial arteriovenous lesions. Different classification strategies have been proposed in the course of the years. None of them seems to guide the treatment strategy. OBJECTIVE: We expose the experience of the vascular group at Niguarda Hospital and we propose a very practical classification method based on the location of the shunt. We divide dAVF in sinus and non-sinus in order to simplify our daily practice, as this classification method is simply based on the involvement of the sinuses. MATERIAL AND METHODS: 477 intracranial dural arteriovenous fistulas have been treated. 376 underwent endovascular treatment and 101 underwent surgical treatment. Cavernous sinus DAVFs and Galen ampulla malformations have been excluded from this series as they represent a different pathology per se. 376 dAVFs treated by endovascular approach: 180 were sinus and 179 were non-sinus. 101 dAVFs treated with surgical approach: 15 were sinus and 86 were non-sinus. DISCUSSION: Of the 477 intracranial dAVF the recorded mortality and severe disability was 3% and morbidity less than 4%. All patients underwent a postoperative DSA with nearly 100% of complete occlusion of the fistula. At a mean follow-up of 5 years in one case there was a non-sinus fistula recurrence, due to the presence of a partial clipping of "piè" of the vein. CONCLUSIONS: The sinus and non-sinus concept has guided our institution for years and has led to good clinical results. This paper intends to share this practical classification with the neurosurgical community.

Clinical considerations on a right operculo-insular cavernous angioma: an illustrative case.

The insular cortex is considered one of the most complex regions of the brain, defined as the "hub" of somatosensory areas. Here, we examine the case of a surgically treated haemorrhagic cavernoma involving the middle and posterior insular cortex, presenting both sensory, gustative and speech symptoms. By reviewing the recent findings in humans' and primates' basic research, we illustrated clinical and radiological correlations of the reported case, confirming insular role in sensitive and gustatory functions.

Acute presentation of Chiari 1 malformation in children.

PURPOSE: To review the literature about the acute presentation of Chiari 1 malformation in children, with a focus on acute cervical cord syndromes with impairment of the cortico-spinal tract. To analyze the possible precipitating factors and the pathophysiology of the acute onset. METHOD: Illustrative case presentation with literature review. RESULTS: The literature includes just a few dozens of children with acute presentation of Chiari 1 malformation. The more frequent presentations consist of oropharyngeal dysfunction, cranial nerve impairment, high intracranial pressure, peripheral motor deficit. Acute impairment of cervical long tracts is very rare and we could find only 16 previously reported cases of cervical cord impairment with quadriparesis or hemiparesis. CONCLUSIONS: Nowadays, a lot of asymptomatic Chiari 1 malformations are frequently observed owing to the wide diffusion of magnetic resonance imaging. This raised the question about the management of these patients. Despite severe and even lethal manifestations being reported in previously asymptomatic patients, the absolute rarity of acute deterioration does not justify prophylactic surgery. The diagnosis of Chiari malformation may be initially difficult in patients with isolated, acute, and unusual presentations but physicians should bear in mind its possibility, because prompt cranio-cervical decompression may be decisive.

Surgical management of Chiari malformation type II.

BACKGROUND: Chiari malformation type II is present in almost all patients with myelomeningocele but usually remains asymptomatic. Symptoms are generally more severe in neonates, who have the worst prognosis. The association symptoms/hydrocephalus is well known, and first treatment usually consists of ensuring adequate ventricular drainage. Craniovertebral decompression may be required in patients who do not improve after drainage. However, mechanisms of symptom development are not yet completely understood, timing and techniques of surgery are not codified, long-term evolution is poorly reported, and there are few paper reporting clinical onset and treatment in older patients. METHODS: We reviewed our personal series of 42 consecutive symptomatic patients that required surgical treatment. Age at surgery ranged from 1 week to 44 years (mean 6.6 years). Surgical timing strictly depended on clinical conditions: urgent management in the more compromised patients (usually infants) and elective treatment before severe deterioration in patients with less severe conditions. All patients first underwent external ventricular drainage, which resolved the symptomatology in 17 cases (40%). Craniocervical decompression was required by 25 patients (60%) who received no benefit from the ventricular drainage. RESULTS: Early mortality (2 cases = 4.7%) occurred only in neonates. Clinical improvement was achieved in 37 of 40 survivors (92%). During a follow-up ranging from 2 to 20 years (mean 10.3 years), late mortality consisted of 4 cases (10%), mainly due to cardio-respiratory arrest. Twenty-two patients (55%) required surgery for shunt malfunction and 4 for cord detethering. Six patients (15%) required reoperation owing to symptom recurrence. CONCLUSION: Early treatment of symptomatic Chiari II malformations may warrant satisfactory results in a significant number of patients, even in neonates. Nevertheless, overall mortality remains relatively high, throughout the patient life. Formal transition programs and adult spina bifida care processes have become crucial.

Complications of Halo Placement.

BACKGROUND: The halo vest is widely used throughout the world to manage craniovertebral and cervical instabilities. It can be used for postoperative immobilization or as an alternative to surgical fixation. METHOD: In this paper we present some cases of severe complications from our own practice and review the literature on halo complications. RESULTS: Like any therapeutic manoeuvre, halo placement may be followed by various complications. In the meantime, modern techniques of fixation offer safe and immediate stabilization. CONCLUSION: The halo vest remains a formidable method for cervical immobilization. However, it should not be used a priori instead of surgery.

Transplant of Adult Bone for Reconstruction of a Large Post-Traumatic Cranial Defect in a Very Young Baby.

Large cranial defects in very young patients are challenging. The ideal material for cranioplasty in this age group has not yet been identified. Cryopreserved autologous bone presents very high rates of failures, acrylic resins pose a number of compatibility problems, bioceramics may be contraindicated, and autografts may be not adequate for repair of large defects. We present an 18-month-old baby with a large post-traumatic cranial defect which was repaired by assembling a new bone flap on a sterile stereolithographic 3-D model. This customized newly assembled flap consisted of a scaffold of autologous bone (from vault duplication) sustaining 2 large grafts of homologous cadaveric bone. It was adequately modeled and contoured on the 3-D model using metallic plates and screws. Immediately after implantation on the skull, the metallic devices were progressively replaced by reabsorbable material, thus maintaining the previously obtained flap profile. In this paper we detail this original technique which was developed to manage this specific patient.

Aesthetic Cranial Vault Expansion in a Child With Slit Ventricle Syndrome and Eumorphic Face.

Ventricular shunting procedures represent the classical surgical treatment for hydrocephalus. Slit ventricle syndrome (SVS) with craniocerebral disproportion (CCD) and secondary craniosynostosis (SCS) is a well-known but uncommon complication following cerebrospinal fluid (CSF) shunting in children. Its general management includes shunt upgrade or revision, placement of anti-siphon devices, lumbo-peritoneal shunting, and endoscopic third ventriculostomy. Cranial expansion is generally considered a major procedure and is indicated when less invasive treatments fail. In these cases, SVS and associated SCS have been usually managed through anterior cranial vault expansion. This procedure aims to decrease the risk of further shunt revisions and to improve neurologic symptoms, but it takes the disadvantage of considerable iatrogenic alterations of the facial proportions. The authors report a case of a 6-year old boy with SVS and SCS, who maintained eumorphic face and was treated by an innovative post-coronal vault expansion ensuring a wide volume increase while avoiding any change of facial conformation.

Homologous Banked Bone Grafts for the Reconstruction of Large Cranial Defects in Pediatric Patients.

PURPOSE: Autogenous bone represents the best material in pediatric reconstructive cranioplasty because of its compatibility with growth; however, its availability is limited. Alternative use of alloplastic materials would have the advantage of unlimited amount, but shows an increased risk of complications and incompatibility with growth. Fresh frozen banked cadaveric bones could be ideal for the reconstruction of large cranial defects in growing patients, because it offers unlimited amount of structural grafts with biomechanics properties quite similar to the autologous bones. RESULTS: The authors report 2 cases of growing patients (13 months female and 9 years old male) undergoing the reconstruction of large (about 70 cm and 50 cm respectively) cranial vault defects, by using structural homologous banked bone grafts.Analytic main reconstruction materials risks/benefits evaluation, literature review of few previously reported pediatric cranioplasty with homologous bone, and both clinical cases satisfactory radiologic long-term results (beyond 4 years of F.U.) are reported. CONCLUSION: Structural homologous banked bone grafts appear as a valid solution for pediatric canioplasty reconstruction of wide defects, entailing the advantages of available without limitations and compatibility with future growth. The risk of transmissible infections seems minimal and is totally counterbalanced by the stability of long-term results.

Craniovertebral fusion in an infant using struts of banked adult bone.

PURPOSE: The aim of this paper is to discuss the problems of craniocervical instability and craniocervical fusion in infancy. Despite the relative frequency of carniovertebral joint malformations, actual instability is quite rare in infancy. METHODS: An infant 8 months of age presented with tetraparesis and sleep apnea due to a complex malformation of her craniovertebral joint. An initial attempt at conservative treatment using a rigid neck collar failed, so the patient was surgically managed by the onlay placement of two autologous rib grafts. The rigid collar was maintained for 5 months. RESULTS: Both rib grafts progressively reabsorbed within a few months, while the clinical deficits recurred. Reoperation consisted of occipitocervical interposition of two robust struts of banked cadaveric adult fibula. This time, the skull appeared mature enough to allow immobilization by the halo system. Adequate occipitocervical fusion was eventually achieved, and the patient fully recovered. CONCLUSIONS: To the best of our knowledge, there is no other reported case of an infant undergoing craniovertebral fusion using cadaveric adult bone. When screw placement is not considered advisable to manage small infants, appropriate stability may be obtained using struts of robust cadaveric bone. A meticulous carpentry technique with graft interposition under compression and adequate postoperative immobilization remains mandatory.

Traumatic injuries to the craniovertebral junction: a review of rare events.

The craniovertebral junction is a specific region of the spine with unique anatomical and biomechanical properties that yields a wide variety of injury patterns. Junctional traumatic fractures and/or dislocations are widely reported in clinical practice, but we could identify only a subgroup of upper cervical spine traumatic injuries with very few cases reported in the literature, and for this reason may be considered rare. In some of these cases, the absence of spinal biomechanical instability, in association with moderate clinical symptoms (neck stiffness and pain) and the difficulty in fracture identification through standard cervical radiographs, leads to a high percentage of missed injuries. In other cases, traumatic events have been commonly described only in autopsy series due to the high degree of spinal biomechanical instability. Herein, we have summarized all the relevant literature concerning this issue and also included our cases, with the aim of emphasizing prompt diagnosis and correct management. We provide a guide for correctly identifying "rare" craniovertebral junction traumatic injuries.

Surgical Treatment of Complex Craniofacial Fractures.

OBJECTIVE: Severe craniofacial fractures may present different needs in treating intracranial lesions over facial injuries. This paper examines the results of our strategy, consisting of a single-stage combined neurosurgical-maxillofacial treatment. METHODS: A retrospective review was conducted of 33 consecutive patients with complex fractures of the anterior cranial fossa and facial skeleton, who required elective surgery for craniofacial reconstruction. Patients who required emergency surgery for intracranial clots or penetrating wounds were excluded. In all cases, all or almost all the anterior skull-base was injured with compound fractures of the frontal sinus, the orbital roofs, the lamina cribrosa, and the planum sphenoidale. In all cases, the prioritization of treatment was carefully discussed, and surgical timing and strategy were agreed. RESULTS: There was 1 dead. Olfactory injuries were always found intraoperatively. There were no mucoceles, CSF-leak recurrences, cranial infections, or neurologic worsening. The functional and neurologic results were highly satisfactory. CONCLUSIONS: The one-stage surgical treatment of complex craniofacial fractures has numerous advantages, including the possibility of reducing facial fractures without the risk of CSF leaks. It also eliminates the need for repeated procedures in fragile patients, and the need to dismantle the facial reconstruction if the skull base repair is performed later. The main issue is the surgical timing, considering that the maxillofacial surgeon usually favors early facial repair, whereas the neurosurgeon generally prefers delayed manipulation of the contused frontal lobes. A timeframe of 10-14 days after trauma may be a good compromise for safe procedures with excellent neurologic and functional outcomes.

PEG hydrogel sealant versus fibrin glue in posterior fossa surgery: an economic comparison across five European countries.

Aim: Posterior cranial fossa (PCF) surgery is associated with complications, including cerebrospinal fluid (CSF) leakage. Dural sealants such as polyethylene glycol (PEG)-based hydrogels and fibrin glue can prevent CSF leaks, with evidence suggesting PEG hydrogels may outperform fibrin glue. However, the budget impact of using PEG hydrogels in PCF surgeries in Europe is unclear. Materials & methods: A decision tree was developed based on a previous US model, to assess the budget impact of switching from fibrin glue to PEG hydrogel in PCF surgery across five European countries. Input costs were derived from published sources for the financial year 2022/2023. Health outcomes, including CSF leaks, were considered. Results: The model predicted that using PEG hydrogel instead of fibrin glue in PCF surgery can lead to cost savings in five European countries. Cost savings per patient ranged from EUR 419 to EUR 1279, depending on the country. Sensitivity analysis showed that the incidence of CSF leaks and pseudomeningoceles had a substantial impact on the model's results. Conclusion: PEG hydrogels may be a cost-effective alternative to fibrin glue in PCF surgery. The model predicted that cost savings would be mainly driven by a reduction in the incidence of postoperative CSF leaks, resulting in reduced reliance on lumbar drains, reparative surgery and shortened hospital stays.

Single fracture in the atlas vertebral arch: analysis of an unusual event.

STUDY DESIGN: Retrospective study. OBJECTIVE: The aim of this study is to show that a single traumatic fracture of the atlas is unusual but not rare and requires specific management strategies, which can be highlighted by the study of the junctional ligaments and membranes. SUMMARY OF BACKGROUND DATA: A single traumatic fracture of the atlas arch is considered a rare event and has been analyzed in few case reports. Ligaments and membranes play a primary role in providing stability to the craniovertebral junction area. METHODS: Here, we report 10 cases of a single traumatic fracture of the atlas arch: 4 cases were part of our series of spine injuries and were studied by magnetic resonance imaging during the acute phase to assess the junctional ligaments. The remaining 6 cases were obtained from the Literature. RESULTS: Indirect signs of a traumatic ligamentous injury were found only in 1 patient. However, in all cases, these fractures were considered biomechanically stable and all patients were discharged with a rigid collar. During the follow-up, all patients reported an improvement in their neck pain and tenderness, with radiologic signs of bone healing. CONCLUSIONS: A single fracture of the atlas arch is an unusual traumatic event that results from slow-force impact. Medical experience in treating this specific fracture subtype is nowadays poor because of the paucity of the literature; thus, this unusual condition may either be underestimated or even overstudied and overtreated. Nowadays, it seems reasonable to assume that the management should be conservative in all cases and that magnetic resonance imaging often plays only a marginal role.

Reoperation in Chiari-1 Malformations.

(1) Background: The issue of unsuccessful surgery for Chiari-1 malformation (CM-1), as well as its potential causes and possible solutions, remains poorly documented and studied. (2) Methods: From a retrospective review of a personal series of 98 patients undergoing treatment for CM-1 during the past 10 years, we created two study groups. Group 1: 8 patients (8.1%) requiring additional surgeries owing to postoperative complications (7 cerebrospinal fluid leakage, 1 extradural hematoma); 7 patients (7.1%) undergoing reoperations for failed decompression during the follow-up. Group 2: During the same period, we also managed 19 patients who had previously been operated on elsewhere: 8 patients who required adequate CM-1 treatment following extradural section of the filum terminale; 11 patients requiring reoperations for failed decompression. Failed decompression was managed by adequate osteodural decompression, which was associated with tonsillectomy (6 cases), subarachnoid exploration (8 cases), graft substitution (6 cases), and occipito-cervical fixation/revision (1 case). (3) Results: There was no mortality or surgical morbidity in Group 1. However, one patient's condition worsened due to untreatable syrinx. In Group 2, there were two cases of mortality, and surgical morbidity was represented by functional limitation and pain in the patient who needed revision of the occipitocervical fixation. Twenty patients improved (58.8%), 6 remained unchanged (32.3%), 1 worsened (2.9%) and 2 died (5.9%). (4) Conclusions: The rate of complications remains high in CM-1 treatment. Unfortunately, a certain rate of treatment failure is unavoidable, but it appears that a significant number of re-operations could have been avoided using proper indications and careful technique.