Prognostic risk factors for early outcomes of patients with myelomeningocele: a prospective study.

INTRODUCTION: Myelomeningocele (MMC) is a prevalent form of neural tube defect. Despite advancements in treatment, MMC still poses significant health risks, including complications leading to chronic disability and mortality. Identifying prognostic risk factors for early outcomes is crucial for tailored intervention strategies. METHODS: This prospective study involved newborns and infants diagnosed with MMC who underwent surgery between 2020 and 2023 at Urmia University of Medical Sciences. Demographic data and surgical outcomes were collected, and participants were followed up for six months. Statistical analyses were conducted using descriptive statistics, Chi-Square, and independent t-test. RESULTS: The study included 29 MMC cases, with an incidence rate of 1.4 per 10,000 live births. Lesions were predominantly located in the lumbar spine. Although mortality rates appeared to increase with ascending lesion sites, this trend was not statistically significant. Short-term outcomes revealed high morbidity and mortality rates, with neurological deficits being the most prevalent complication. Multivariable analysis identified head circumference as a significant predictor of adverse outcomes (IRR = 1.37, 95% CI = 1.02 to 1.86, p = 0.04). Furthermore, an increase in birth weight was associated with a reduction in the incidence of requiring a ventriculoperitoneal shunt (IRR = 0.99, 95% CI = 0.998 to 0.999, p = 0.02). CONCLUSION: This prospective study highlights prognostic risk factors for early outcomes in MMC patients, emphasizing the need for personalized intervention strategies. By addressing modifiable risk factors and implementing targeted interventions, healthcare providers can strive to improve outcomes and enhance the quality of life for MMC patients.

Clear cell meningiomas-case presentation, review of radiographic identifiers, and treatment approaches.

Spinal clear cell meningiomas (CCMs) are a rare histological subtype of meningiomas that pose preoperative diagnostic challenges due to their radiographic similarities with other lesions. They are also more aggressive, exhibiting higher rates of recurrence, particularly in pediatric patients. Overcoming diagnostic challenges of these tumors can improve patient outcomes. In this report, we describe a case of a pediatric patient presenting with a lumbar CCM in whom we were able to obtain gross total resection. Our report reviews previously identified predictors of CCM recurrence, including the Ki-67 proliferation index, number of spinal segments involved, and hormonal influences related to age and sex. We describe the characteristic radiographic features that differentiate spinal CCMs from other tumors to improve pre-operative diagnosis. Furthermore, we provide our rationale for adjuvant therapy for pediatric patients to refine treatment protocols for these rare tumors.

A comprehensive systematic review and meta-analysis study in comparing decompressive craniectomy versus craniotomy in patients with acute subdural hematoma.

There are two controversial surgery methods which are traditionally used: craniotomy and decompressive craniectomy. The aim of this study was to evaluate the efficacy and complications of DC versus craniotomy for surgical management in patients with acute subdural hemorrhage (SDH) following traumatic brain injury (TBI). We conducted a comprehensive search on PubMed, Scopus, Web of Science, and Embase up to July 30, 2023, using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses checklist. Relevant articles were reviewed, with a focus on studies comparing decompressive craniectomy to craniotomy techniques in patients with SDH following TBI. Ten studies in 2401 patients were reviewed. A total of 1170 patients had a craniotomy, and 1231 had decompressive craniectomy. The mortality rate was not significantly different between the two groups (OR: 0.46 [95% CI: 0.42-0.5] P-value: 0.07). The rate of revision surgery was insignificantly different between the two groups (OR: 0.59 [95% CI: 0.49-0.69] P-value: 0.08). No significant difference was found between craniotomy and decompressive craniectomy regarding unilateral mydriasis (OR: 0.46 [95% CI: 0.35-0.57] P-value < 0.001). However, the craniotomy group had significantly lower rates of non-pupil reactivity (OR: 0.27 [95% CI: 0.17-0.41] P-value < 0.001) and bilateral mydriasis (OR: 0.59 [95% CI: 0.5-0.66] P-value: 0.04). There was also no significant difference in extracranial injury between the two groups, although the odds ratio of significant extracranial injury was lower in the craniotomy group (OR: 0.58 [95% CI: 0.45-0.7] P-value: 0.22). Our findings showed that non-pupil and bilateral-pupil reactivity were significantly more present in decompressive craniectomy. However, there was no significant difference between the two groups regarding mortality rate, extracranial injury, revision surgery, and one-pupil reactivity.

Volumetric segmentation in the context of posterior fossa-related pathologies: a systematic review.

BACKGROUND: Segmentation tools continue to advance, evolving from manual contouring to deep learning. Researchers have utilized segmentation to study a myriad of posterior fossa-related conditions, such as Chiari malformation, trigeminal neuralgia, post-operative pediatric cerebellar mutism syndrome, and Crouzon syndrome. Herein, we present a summary of the current literature on segmentation of the posterior fossa. The review highlights the various segmentation techniques, and their respective strengths and weaknesses, employed along with objectives and outcomes of the various studies reported in the literature. METHODS: A literature search was conducted in PubMed, Embase, Cochrane, and Web of Science up to November 2023 for articles on segmentation techniques of posterior fossa. The two senior authors searched through databases based on the keywords of the article separately and then enrolled joint articles that met the inclusion and exclusion criteria. RESULTS: The initial search identified 2205 articles. After applying inclusion and exclusion criteria, 77 articles were selected for full-text review after screening of titles/abstracts. 52 articles were ultimately included in the review. Segmentation techniques included manual, semi-automated, and fully automated (atlas-based, convolutional neural networks). The most common pathology investigated was Chiari malformation. CONCLUSIONS: Various forms of segmentation techniques have been used to assess posterior fossa volumes/pathologies and each has its advantages and disadvantages. We discuss these nuances and summarize the current state of literature in the context of posterior fossa-associated pathologies.

A Case Report of Infant-Type Hemispheric Glioma with a Novel GAB1-ABL2 Kinase Fusion Treated with Dasatinib.

INTRODUCTION: Infant-type hemispheric glioma (IHG) is a rare form of cancer that affects newborns and infants. It is classified as a pediatric-type high-grade glioma and typically harbors receptor tyrosine kinase (RTK) gene fusions. Here, we present the finding of a novel gene fusion IHG treated with a targeted therapy that has yet to be implemented for any other IHG case to date. CASE PRESENTATION: We report the case of a 12-month-old boy with IHG who presented with obstructive hydrocephalus due to a large mass in the right frontal lobe. The patient initially underwent mass resection, but subsequent imaging showed rapid interval progression of the residual tumor. Comprehensive molecular analysis of the tumor tissue revealed a novel GAB1-ABL2 gene fusion, and the patient was started on dasatinib, an ABL kinase inhibitor. Shortly after initiation of dasatinib treatment, there was a significant reduction in tumor size and enhancement, followed by stabilization of disease. DISCUSSION: The patient's robust response to treatment suggests that dasatinib is an effective targeted therapy for IHG harboring a GAB1-ABL2 gene fusion. This finding may inform future investigations into the disease processes of IHG and help guide the diagnosis and treatment of IHG in the absence of previously identified gene fusions, improving clinical management of this vulnerable patient population.

A nine-month-old boy with regression of milestones and severe constipation: an unusual case of a large spinal NTRK1 fusion pilocytic astrocytoma.

INTRODUCTION: Pilocytic astrocytoma, a World Health Organization grade 1 tumor, is the most common brain tumor in children between 5 and 14 years of age and the second most common in children younger than 5 and older than 14. Although classical to the cerebellum and hypothalamic regions, it can also arise in the spinal cord. Larotrectinib, a selective inhibitor of tropomyosin receptor kinase, has been effective in pediatric tumors with NTRK fusion mutations in children as young as 1-month-old. CASE: We share the case of a 9-month-old boy who presented with a 4-month history of regression of his milestones and severe constipation who was found to have a large spinal pilocytic astrocytoma with multiple intracranial periventricular lesions.

STAT5b gain-of-function disease in a child with mycobacterial osteomyelitis of the skull: rare presentation of an emerging disease entity.

PURPOSE: STAT proteins play a key role in several cellular functions related to cell development, differentiation, proliferation, and survival. Persistent STAT activation due to somatic STAT5bN642H gain-of-function mutation is a rare mechanism of STAT dysregulation that results in hypereosinophilia, frequent infections, leukemias, and pulmonary diseases. Herein, we describe a case of a child with a rare early onset STAT5b gain-of-function disease treated with targeted JAK inhibition who developed a cranial Mycobacterium avium osteomyelitis. METHODS: A 3-year-old male with a known STAT5b gain-of-function mutation presented with a 10-day history of a firm, immobile, non-painful cranial mycobacterium mass with dural infiltration located anterior to the coronal suture. Stepwise management finalized with complete resection of the lesion with calvarial reconstruction. A case-based literature review was performed evaluating all patients with this mutation who developed cranial disease. RESULTS: The patient was symptom and lesion-free at 1 year since surgical resection and initiation of triple mycobacterial pharmacotherapy. Our literature review demonstrated the rarity of this disease, as well as other presentations of this disease in other patients. CONCLUSION: Patients with STAT5b gain-of-function mutations have attenuated Th1 responses and are treated with medications, such as JAK inhibitors, which further inhibit other STAT proteins that regulate immunity against rare infectious entities, such as mycobacterium. Our case highlights the importance of considering these rare infections in patients on JAK inhibitors and with STAT protein mutations. Possessing a clear mechanistic understanding of this genetic mutation, its downstream effect, and the consequences of treatment may enhance a physician's diagnostic and clinical management of similar patients in the future.

Pediatric brain aneurysms: a review of 1458 brain MR angiograms.

PURPOSE: To evaluate clinical and imaging characteristics of pediatric brain aneurysms. MATERIALS AND METHODS: A retrospective review of 1458 MR angiograms of pediatric patients (≤18 years old) obtained between 2006 and 2021 was performed. A non-infundibular arterial luminal outpouching larger than 1mm in size was identified as an "Intracranial aneurysm." Patient demographics, clinical presentations, and predisposing risk factors, including family history and underlying medical conditions, were reviewed. MRA images were analyzed for aneurysm location, number, maximum diameter, and interval changes on follow-up. RESULTS: Forty-nine (3.3%) patients (30 females, 19 males) with 64 intracranial aneurysms were identified with an average age of 13.71 ± 3.67 years. Eleven (22.4%) patients had multiple aneurysms. An underlying systemic illness was observed in 81.6% (40/49) cases, with sickle cell disease as the most frequent (25/49, 51%) diagnosis. A first-degree family history of intracranial aneurysms was recognized in 36/1458 (2.5%) patients. However, no intracranial aneurysm was found in this group. While 02/49 (4%) patients presented with acute SAH, headache was the most common (16/49, 32.7%) symptom at presentation in unruptured cases. The majority (47/64, 73.4%) of the aneurysms were located in the anterior circulation, with the ICA ophthalmic segment being most frequently (24/47, 51%) involved. Most (54/64, 84.4%) aneurysms were smaller than 4mm in size at the time of diagnosis. At least one follow-up MRA was obtained in 72.3% (34/47) of the unruptured aneurysms cohort. There was no change in the aneurysm size and morphology in 31/34 (91.2 %) patients over an average imaging follow-up of 39.6 months. Three (6%) patients demonstrated an interval increase in the aneurysm size. SAH patients (n=2) and two unruptured aneurysm patients with an interval increase in size were successfully treated with endovascular techniques. CONCLUSION: Female predominance with a higher frequency of small and unruptured intracranial aneurysms was recognized in our cohort. A higher incidence of an underlying systemic illness, especially sickle cell disease, was also noted. Most intracranial aneurysms in children appear to remain stable. However, there seems to be the risk of an aneurysm size increase which warrants regular clinical and imaging follow-up.

Neurological Sequelae of COVID-19.

BACKGROUND: Though primarily a pulmonary disease, Coronavirus disease 2019 (COVID-19) caused by the SARS-CoV-2 virus can generate devastating disease states that affect multiple organ systems including the central nervous system (CNS). The various neurological disorders associated with COVID-19 range in severity from mild symptoms such as headache, or myalgias to more severe symptoms such as stroke, psychosis, and anosmia. While some of the COVID-19 associated neurological complications are mild and reversible, a significant number of patients suffer from stroke. Studies have shown that COVID-19 infection triggers a wave of inflammatory cytokines that induce endothelial cell dysfunction and generate coagulopathy that increases the risk of stroke or thromboses. Inflammation of the endothelium following infection may also destabilize atherosclerotic plaque and induce thrombotic stroke. Although uncommon, there have also been reports of hemorrhagic stroke associated with COVID-19. The proposed mechanisms include a blood pressure increase caused by infection leading to a reduction in angiotensin converting enzyme-2 (ACE-2) levels that results in an imbalance of the renin-angiotensin system ultimately manifesting inflammation and vasoconstriction. Coagulopathy, as demonstrated by elevated prothrombin time (PT), has also been posited as a factor contributing to hemorrhagics stroke in patients with COVID-19. Other neurological conditions associated with COVID-19 include encephalopathy, anosmia, encephalitis, psychosis, brain fog, headache, depression, and anxiety. Though there are several hypotheses reported in the literature, a unifying pathophysiological mechanism of many of these disorders remains unclear. Pulmonary dysfunction leading to poor oxygenation of the brain may explain encephalopathy and other disorders in COVID-19 patients. Alternatively, a direct invasion of the CNS by the virus or breach of the blood-brain barrier by the systemic cytokines released during infection may be responsible for these conditions. Notwithstanding, the relationship between the inflammatory cytokine levels and conditions such as depression and anxiety is contradictory and perhaps the social isolation during the pandemic may in part be a contributing factor to some of the reported CNS disorders. OBJECTIVE: In this article, we review the current literature pertaining to some of the most significant and common neurological disorders such as ischemic and hemorrhagic stroke, encephalopathy, encephalitis, brain fog, Long COVID, headache, Guillain-Barre syndrome, depression, anxiety, and sleep disorders in the setting of COVID-19. We summarize some of the most relevant literature to provide a better understanding of the mechanistic details regarding these disorders in order to help physicians monitor and treat patients for significant COVID-19 associated neurologic impairments. METHODS: A literature review was carried out by the authors using PubMed with the search terms "COVID-19" and "Neurology", "Neurological Manifestations", "Neuropsychiatric Manifestations", "Stroke", "Encephalopathy", "Headache", "Guillain-Barre syndrome", "Depression", "Anxiety", "Encephalitis", "Seizure", "Spasm", and "ICUAW". Another search was carried out for "Long-COVID" and "Post-Acute COVID-19" and "Neurological Manifestations" or "Neuropsychiatric Manifestations". Articles such as case reports, case series, and cohort studies were included as references. No language restrictions were enforced. In the case of anxiety and depression, attempts were made to focus mainly on articles describing these conditions in infected patients. RESULTS: A total of 112 articles were reviewed. The incidence, clinical outcomes, and pathophysiology of selected neurological disorders are discussed below. Given the recent advent of this disease, the incidence of certain neurologic sequelae was not always available. Putative mechanisms for each condition in the setting of COVID-19 are outlined.

Posterior ischemic optic neuropathy following supine craniotomy for epidural abscess in a child.

Post-operative vision loss (POVL) can be a devastating complication of neurosurgical procedures and is unusual in the pediatric population. Mechanisms of POVL include direct optic nerve injury, vascular occlusion, or indirect malperfusion resultant from surgeries with substantial blood loss or fluid shifts, with prone positioning being a major risk factor for these events. Posterior ischemic optic neuropathy (PION) is a rare cause of POVL and is associated with a poor prognosis for recovery of visual function. We present a case of PION following a supine bifrontal craniotomy for a frontal epidural abscess secondary to pan-sinusitis in a pediatric patient. This is an unusual reported case in that no additional traditional risk factors were identified. We present clinical and radiographic findings, diagnostic considerations, treatment strategies, and a literature review. The patient was managed medically and recovered substantial vision in the affected eye.

Surgical considerations in Labrune syndrome.

PURPOSE: Labrune syndrome (LS) is a rare white matter disease characterized by leukoencephalopathy with intracranial calcification and cysts (LCC). While the intracranial cyst characteristics of LS are for the most part stable, some may require surgical intervention when they develop associated hemorrhage and/or mass effect. To date, no review of the surgical outcomes of cyst decompression in LS has been performed. CASE PRESENTATION: We report the case of a 16-year-old girl with LS who presented with progressive right hemiparesis from an enlarging hemorrhagic left thalamic cyst. The patient underwent frameless stereotactic cyst aspiration and Ommaya reservoir placement and her hemiparesis subsequently improved. Serial monitoring demonstrated stable decompression of the cyst. CONCLUSIONS: The pathophysiology of LS is thought to be diffuse cerebral microangiopathy and it is thought that these microhemorrhages contribute to the formation of intracranial cysts as well as diffuse calcifications. Indications for surgical intervention in LS are not well established and the heterogeneity of lesions compels them to be managed on a case-by-case basis. Based on our literature review, surgery is the standard treatment of choice for patients with progressive symptoms and growing lesions on imaging studies, with outcomes favoring less-invasive stereotactic approaches with contingencies of reservoir placement when cysts recur.

Split cord malformation and tethered cord syndrome: case series with long-term follow-up and literature review.

PURPOSE: To date, the description of the natural course of concurrent tethered cord syndrome with a low-lying conus medullaris and split cord malformation is lacking in the literature. We report a cohort of adult and pediatric patients with concurrent malformations and long-term follow-up. METHODS: Patients with concurrent diagnoses of split cord malformation and tethered cord (radiographic evidence supporting clinical symptomatology) were identified between 2000 and 2020. Patients without sufficient documentation or at least 6-month follow-up were excluded. RESULTS: Nine patients were identified with an average of 8.9 years follow-up (range 2-31 years). The most common symptoms were radiating leg pain and lower extremity paresthesias, occurring in 44% of patients; and bladder/bowel dysfunction, worsening scoliosis, and acute motor deterioration were less common. Two patients were successfully treated conservatively for mild leg pain and paresthesias. For those who underwent surgery, all experienced symptomatic relief upon first follow-up. Two had late symptomatic recurrence; one 4 and 8 years after initial surgery; and the other, 11, 26, and 31 years after initial surgery. CONCLUSION: The rarity of concurrent split cord and tethered cord syndrome with a low-lying conus makes management difficult to formulate. This series supplements our knowledge of the long-term outcomes and lessons learned from the management of these patients. Approximately 25% of patients were managed conservatively and had symptomatic improvement. For surgically managed patients, with intractable pain or worsening neurological function, symptoms can still recur over a decade after intervention. Reoperation, however, can still be beneficial, can provide years of relief, and should be considered.

The limits of endoscopic endonasal approaches in young children: a review.

INTRODUCTION: The endoscopic endonasal approach (EEA) provides visualization of four deep surgical corridors (transcribiform, transtubercular, transsellar, and transclival) with superior illumination and specialized deep-reaching instruments, as compared to microscopic techniques. Several studies have evaluated EEAs in children but do not stratify for the very young of age, whose particularly small nares and developmental anatomy may limit endonasal instrumentation. METHODOLOGY: A comprehensive review of EEAs in infants and children to age 4 was performed to determine the limitations in this age group. RESULTS: Eighteen studies were identified describing this approach for pediatric patients and the surgical caveats and limitations were reviewed. In very small children, CSF leaks, meningioencephaloceles, tumors of the anterior skull base, and lesions at the rostral cervical spine have been successfully treated endonasally. While newer studies advocate using 2.7-mm diameter (18-cm length) lenses, 4-mm diameter rigid lenses have been used without technical difficulty. The youngest patient in whom an EEA was used was a 6-week-old for a dermoid resection. Some have advocated that due to the small nares, approaches via bilateral entry are optimal for multiple instruments, however, others, including authors of a series of 28 repaired CSF leaks demonstrate successful single nare access. DISCUSSION: EEAs are associated with less blood loss, are less likely to hinder normal growth of the skull and midface, and allow for the resection of even malignant lesions. Despite the limitations of the frontal, ethmoid, and sphenoid sinuses before age 3, reports have not documented insurmountable difficulty with EEAs even in infants. 2.7-mm diameter endoscopes are favored unilaterally or bilaterally to treat both benign and malignant lesions and preserve the young patient's facial anatomy better than older methods. Ever improving technology has facilitated the use of this approach in patients it would otherwise be infeasible for in the past, but it still cannot overcome the anatomical constraints of certain young patients in which this approach remains unindicated. Patient selection is therefore of utmost importance and the risks and benefits of more extensive approaches in these cases must be considered.

Dual Myelomeningoceles in Twins: Case Report, Review, and Insights for Etiology.

INTRODUCTION: Despite folate supplementation, neural tube defects (NTDs) still occur in 0.5-1.0/1,000 pregnancies, with 30-50% not preventable with folate. Twinning has increased due to artificial fertilization and in itself predisposes to NTDs at a rate of 1.6/1,000. The contributions of genetic and environmental factors to myelomeningocele development remain poorly understood. Expression patterns of congenital pathologies in twins can sometimes provide etiological insight. Concordance of NTDs in twins is 0.03/1,000, with dual myelomeningocele reported in only 23 pairs, only one of which survived. We present the 24th pair, the 1st to maintain lower extremity motor function. We review all prior cases and discuss implications of twin concordance on the interplay of genetic and environmental influences. Case Report and Review: A new case of female monozygotic twins born to a well-nourished 24-year-old female is reported with details of perioperative care. Prenatal ultrasound showed L3-S4 and L5-S4 myelomeningoceles, Chiari II malformations, and ventriculomegaly. Copy number microarray was unrevealing. Each underwent uncomplicated repair on day of life 1, and ventriculoperitoneal shunt placement on days of life 10 and 16. Both had movement in the legs upon 6-week follow-up. All prior reported cases of concordant twin myelomeningoceles were abstracted and analyzed, revealing persistence of occurrence despite folate supplementation and a majority occurring in dizygotic pairs. The literature is also reviewed to summarize current knowledge of myelomeningocele pathophysiology as it relates to genetic and environmental influences. DISCUSSION: Meticulous surgical and perioperative care allowed for early positive outcomes in each twin. However, etiopathogenesis remains elusive. In general, only of a minority of cases have underlying genetic lesions or clear environmental triggers. Concordance in monozygotic twins argues for a strong genetic influence; yet, literature review reveals a higher rate of concordant dizygotic twins. This, along with the observation of differing resultant phenotypes in monozygotic twins as seen in this case, prompts further investigation into nonfolate environmental influences. While efforts in genetic investigation should continue, the role of teratogens and exposures should not be minimized in research efforts, public health, and family counseling. Clinical genetic testing remains of limited utility in the majority of patients until more is known.

The history of intracranial infections.

The 19th and 20th centuries heralded the advancement of our understanding of surgical infections, reducing the risk of morbidity and mortality to patients by overturning long-held dogmas surrounding infections and perioperative care. These advancements impacted the development and establishment of the field of neurological surgery by minimizing surgical risk through aseptic techniques and promoting surgical benefit via improved neurological localization and surgical technique. Infections were significant contributors to morbidity and mortality for all surgical patients, and historically almost half of patients lost their lives as a consequence of perioperative wound contamination. With advancing understanding of germ theory, contagion, antisepsis, and subsequently asepsis, the surgeon began embracing the knowledge and techniques which would hone their craft and allow for a renaissance in the management of neurological disorders in an unprecedented manner.

Congenital cervical kyphosis in an infant with Ehlers-Danlos syndrome.

BACKGROUND: Ehler-Danlos syndome (EDS) refers to a group of heritable connective tissue disorders; rare manifestations of which are cervical kyphosis and clinical myelopathy. Surgical treatment is described for the deformity in the thoracolumbar spine in adolescents but not for infantile cervical spine. Internal fixation for deformity correction in the infantile cervical spine is challenging due to the diminutive size of the bony anatomy and the lack of spinal instrumentation specifically designed for young children. We describe the first case of successful surgical treatment in an infant with a high cervical kyphotic deformity in EDS. CASE PRESENTATION: A 15-month-old female with EDS presented with several months of regression in gross motor skills in all four extremities. Imaging demonstrated 45° of kyphosis from the C2-4 levels with spinal cord compression. Corrective surgery consisted of a C3 corpectomy and C2-4 anterior fusion with allograft block and anterior fixation with dual 2 × 2 hole craniofacial miniplates, supplemented by C2-4 posterior fusion using four craniofacial miniplates fixated to the lamina. Radiographs at 20 months post-surgery demonstrated solid fusion both anteriorly and posteriorly with maintenance of correction. CONCLUSIONS: Ehlers-Danlos syndrome may present in the pediatric population with congenital kyphosis from cervical deformity in addition to the more commonly seen thoracolumbar deformities.

Virtual modeling, stereolithography, and intraoperative CT guidance for the optimization of sagittal synostosis reconstruction: a technical note.

INTRODUCTION: Sagittal synostosis affects 1 in 1000 live births and may result in increased intracranial pressure, hindrance of normal neural development, and cosmetic deformity due to scaphocephaly. Historically, several approaches have been utilized for surgical correction and recently, computed tomography (CT)-guided reconstruction procedures are increasingly used. In this report, the authors describe the use of a CT-derived virtual and stereolithographic (3D printed) craniofacial models, which are used to guide intraoperative bone placement, and intraoperative CT guidance for confirmation of bone placement, to ensure the accuracy of surgical correction of scaphocephaly, as demonstrated to parents. METHODS: Preoperative high-resolution CT imaging was used to construct 3D image sets of the skulls of two infants (a 14-month-old female and a 6-month-old male) with scaphocephaly. These 3D image sets were then used to create a virtual model of the proposed surgical correction for each of the infants' deformities, which was then printed and made available for use intraoperatively to plan the bone flap, fashion the bone cuts, and optimize graft placement. After the remodeling, adherence to the preoperative plan was assessed by overlaying a CT scan of the remodeled skull with the virtual model. Deviations from the preoperative model were noted. RESULTS: Both patients had excellent postoperative cosmetic correction of head shape and contouring. The mean operative time was 5 h, blood loss was 100 ml, and one child required modification of the subocciput after intraoperative imaging showed a deviation of the reconstruction from the surgical goal as depicted by the preoperative model. CONCLUSION: The addition of neuro-navigation to stereolithographic modeling ensured the accuracy of the reconstruction for our patients and provided greater confidence to both surgeons and parents. While unisutural cases are presented for clarity, correction was still required for one patient. The cost of the models and the additional CT required must be weighed against the complexity of the procedure and possibly reserved for patients with potentially complicated corrections.

Targeted ablation of cholinergic interneurons in the dorsolateral striatum produces behavioral manifestations of Tourette syndrome.

Gilles de la Tourette syndrome (TS) is characterized by tics, which are transiently worsened by stress, acute administration of dopaminergic drugs, and by subtle deficits in motor coordination and sensorimotor gating. It represents the most severe end of a spectrum of tic disorders that, in aggregate, affect ∼ 5% of the population. Available treatments are frequently inadequate, and the pathophysiology is poorly understood. Postmortem studies have revealed a reduction in specific striatal interneurons, including the large cholinergic interneurons, in severe disease. We tested the hypothesis that this deficit is sufficient to produce aspects of the phenomenology of TS, using a strategy for targeted, specific cell ablation in mice. We achieved ∼ 50% ablation of the cholinergic interneurons of the striatum, recapitulating the deficit observed in patients postmortem, without any effect on GABAergic markers or on parvalbumin-expressing fast-spiking interneurons. Interneuron ablation in the dorsolateral striatum (DLS), corresponding roughly to the human putamen, led to tic-like stereotypies after either acute stress or d-amphetamine challenge; ablation in the dorsomedial striatum, in contrast, did not. DLS interneuron ablation also led to a deficit in coordination on the rotorod, but not to any abnormalities in prepulse inhibition, a measure of sensorimotor gating. These results support the causal sufficiency of cholinergic interneuron deficits in the DLS to produce some, but not all, of the characteristic symptoms of TS.

The complex treatment paradigms for concomitant tethered cord and scoliosis: illustrative case.

BACKGROUND: Scoliosis associated with tethered cord syndrome is one of the most challenging spinal deformities to manage. Multiple surgical approaches have been developed, including traditional staged and concomitant procedures, spine-shortening osteotomies, and individual vertebral column resections. OBSERVATIONS: A 10-year-old female presented with congenital kyphoscoliosis with worsening curve progression, tethered spinal cord, and a history of enuresis. The scoliosis had progressed to a 26° coronal curve and 55° thoracolumbar kyphosis. Preoperative magnetic resonance imaging of the spine revealed a tethered cord between the levels of L3-4 and a large kyphotic deformity at L1. The patient underwent laminectomy, during which intraoperative motor signals were lost. A planned hemivertebrectomy at L1 was performed prior to an L4 laminectomy, untethering of the filum terminale, and posterior spinal fusion from T11 to L2. After surgery, the patient experienced transient lower-extremity weakness, with her neurological function improving from baseline over the next 2 months. Ultimately, the goal of this surgery was to halt the progressive decline in motor function, which was successfully achieved. LESSONS: Much remains to be learned about the treatment of this complicated disease, especially in the setting of concomitant scoliosis. This case serves to exemplify the complex treatment paradigms that exist when attempting to manage this clinical syndrome and that more remains to be learned.