Self-Trephination in Cranial Excoriation Disorder.

BACKGROUND AND IMPORTANCE: Trephination is a procedure in which a small hole is made in the skull. Rare cases of self-trephination by individuals seeking medical benefit have been reported. Excoriation disorder is a compulsive skin-picking condition in which an individual self-inflicts cutaneous lesions. Left untreated, severe excoriation disorder can pose significant health risks. CLINICAL PRESENTATION: Here, we describe 5 patients who presented with self-trephination due to a severe form of compulsive cranial excoriation at 2 neighboring academic medical centers over a 4-year period. We review the clinical presentation of self-trephination in cranial excoriation disorder and associated risk factors, surgical and nonsurgical interventions, complications of the disease, treatments, and mortality. Defining clinical characteristics include repetitive self-induced destruction of the scalp and skull with entry into the intracranial compartment, frequent psychiatric comorbidities, infection or injury of the brain with consequent neurological morbidity or mortality, and frequent treatment failures because of poor adherence. CONCLUSION: Self-trephination in cranial excoriation disorder is a severe neuropsychological disorder and neurosurgical emergency that exposes the brain and is often life-threatening. Appropriate therapy requires antibiotics, surgical debridement and repair of the wound, and concomitant effective psychiatric management of the underlying compulsion, including the use of antidepressants and behavioral therapy.

Left-Handed Palming of the Needle Driver: A Technical Report for Surgical Trainees.

Left-handed surgical trainees are uniquely challenged when learning how to suture using standard needle drivers designed for right-handed individuals and often feel disadvantaged in comparison to their right-handed peers. "Palming," a suturing technique that improves suturing mechanics and efficiency, cannot be achieved in the standard manner using the left hand. This paper proposes a previously undescribed technique for palming using the left hand that provides many of the same benefits as standard palming methods using the right hand, potentially reducing a common source of inequity in surgical training.

Explaining the practicum experiences of diagnostic radiography undergraduates in Australia and Ethiopia using the theory of human relatedness.

INTRODUCTION: Practice learning is critical to the development of clinical skills; hence placements are a major component of all pre-registration radiography programmes. Nonetheless, dissatisfaction with practicum experiences is a common reason why students consider leaving such programmes. Providing effective placements which promote retention may not only require better appreciation of students' clinical reflections, but also a more fundamental understanding of the implicit criteria they use to appraise a practicum. This study applied the theory of human relatedness (THR) to the placement experiences of radiography undergraduates to identify the evaluative mechanisms which may underpin these experiences. METHODS: A critical realist investigative approach was employed to reanalyse data regarding the practicum experiences of stakeholders involved in undergraduate diagnostic radiography programmes at two universities in Australia and Ethiopia against the eight core THR concepts, namely connectedness, disconnectedness, parallelism, enmeshment, belonging, reciprocity, mutuality, and synchrony. RESULTS: The findings identified all states of relatedness and processes/social competencies of the THR within the placement experiences of these stakeholders. The degree of positive relatedness a radiography student experiences within a practicum, irrespective of the setting, may affect their clinical performance. CONCLUSION: The findings support the argument that the THR may reflect an implicit set of criteria stakeholders use to evaluate clinical encounters. Additionally, these results are congruent with earlier investigations regarding the practicum reflections of other undergraduate healthcare students. IMPLICATIONS FOR PRACTICE: To enhance student placement experiences, it is necessary to recognise the effect a student's sense of relatedness may have on their self-efficacy and proficiency, modifying pre-practicum preparation and assessment arrangements to inhibit disconnectedness and enmeshment, avoid the need for parallelism, and better cultivate connectedness, belonging, reciprocity, mutuality, and synchrony.

Benefits and limitations of a dual faculty neurosurgeon approach to resection of pediatric craniopharyngioma.

PURPOSE: The utility and safety of including two neurosurgeons for tumor resections is unknown. This study compares outcomes among pediatric patients with craniopharyngiomas operated on with a dual or single surgeon approach (DSA, SSA). METHODS: A single-center review identified all craniopharyngioma transsphenoidal or craniotomy resections from 2000 to 2020. Surgical years of experience (YOE) and rates of 5-year reoperations, complications, recurrence, and postoperative radiotherapy were analyzed. RESULTS: Twenty-six transsphenoidal and 68 craniotomies were identified among 62 patients. Eleven transsphenoidal (42.3%) utilized DSA and 15 utilized (57.7%) SSA. Eight craniotomies (11.8%) were DSA and 60 (88.2%) were SSA. The surgeon for SSA transsphenoidal procedures had a median of 10.7 YOE (IQR: 9.9-13.7) versus 6.6 (IQR: 2.7-16; p = 0.058) for the lead surgeon in DSAs. The co-surgeon in transsphenoidal DSAs had a median of 27 YOE (IQR: 11.8-35.7). The surgeon for SSA craniotomies had a median of 19.3 YOE (IQR: 12.1-26.4) versus 4.5 years (IQR: 1.3-15.3; p = 0.017) for the lead surgeon in DSA cases. The co-surgeon in DSA craniotomies had a median of 23.2 YOE (IQR: 12.6-31.4). Case complexity was similar across transsphenoidal groups. DSA transsphenoidal resections had fewer complications (18% DSA vs. 33% SSA), reoperations (45% vs. 53%), and radiation therapy (9.1% DSA vs. 33% SSA) than SSA. CONCLUSION: Lead surgeons in DSAs are frequently junior surgeons while SSAs typically employ senior surgeons. Outcomes did not significantly differ between DSA and SSA. Mentorship through DSAs does not negatively affect patient care.

Snacking practices from infancy to adolescence: parental perspectives from longitudinal lived experience research in England.

Consumption of snacks and ultra-processed foods (UPF) high in fat, salt and sugar (HFSS) is associated with rising rates of obesity and growing socioeconomic disparities in nutrition. While infancy, childhood and adolescence are critical periods for development of dietary preferences, there remains a dearth of research exploring factors that underpin snacking behaviour over this time. This review aims to address this gap by drawing from qualitative lived experience research, with 122 families of different socioeconomic position (SEP), to explore how the (i) home food environment, (ii) food environment and (iii) social value and meanings of food shape parental provision of snacks. This review shows that snacking holds important meanings in everyday family life, with infants integrated into existing snacking practices from an early age. Price promotions, low-cost and long shelf-lives all make UPF and HFSS snacks an appealing option for many low-SEP parents; while children's requests and preferences for HFSS snacks present a challenge across SEP. However, higher-SEP parents can ensure fresh fruits are always available as an alternative snack, while fruit is described as a financially risky expenditure for low-SEP families. The present findings also indicate that retailers and producers are increasingly promoting 'healthier' snacks through product packaging and marketing, such as 'meets one of your five a day', despite these products displaying similar nutritional profiles to traditional UPF and HFSS snacks. We outline a series of policy recommendations, including extending Healthy Start Vouchers and the Fruit and Vegetable Scheme in schools and action to address misleading product marketing and packaging.

Endoscopic third ventriculostomy with choroid plexus cauterization: predictors of long-term success and comparison with shunt placement for primary treatment of infant hydrocephalus.

OBJECTIVE: Endoscopic third ventriculostomy (ETV) with choroid plexus cauterization (CPC) can avoid ventriculoperitoneal shunt (VPS) dependence in very young hydrocephalic children, although long-term success as a primary treatment in North America has not been previously reported. Moreover, optimal age at surgery, impact of preoperative ventriculomegaly, and relationship to prior cerebrospinal fluid (CSF) diversion remain poorly defined. The authors compared ETV/CPC and VPS placement for averting reoperation, and they evaluated preoperative predictors for reoperation and shunt placement after ETV/CPC. METHODS: All patients under 12 months of age who underwent initial hydrocephalus treatment via ETV/CPC or VPS placement at Boston Children's Hospital between December 2008 and August 2021 were reviewed. Analyses included Cox regression for independent outcome predictors, and both Kaplan-Meier and log-rank rank tests for time-to-event outcomes. Cutoff values for age and preoperative frontal and occipital horn ratio (FOHR) were determined with receiver operating characteristic curve analysis and Youden's J index. RESULTS: In total, 348 children (150 females) were included with principal etiologies of posthemorrhagic hydrocephalus (26.7%), myelomeningocele (20.1%), and aqueduct stenosis (17.0%). Of these, 266 (76.4%) underwent ETV/CPC and 82 (23.6%) underwent VPS placement. Treatment choice largely reflected surgeon preferences before practice shifted toward endoscopy, with endoscopy not considered for > 70% of initial VPS cases. ETV/CPC patients trended toward fewer reoperations, and Kaplan-Meier analysis estimated that 59% of patients would achieve long-term shunt freedom through 11 years (median 42 months of actual follow-up). Among all patients, corrected age < 2.5 months (p < 0.001), prior temporizing CSF diversion (p = 0.003), and excess intraoperative bleeding (p < 0.001) independently predicted reoperation. Among ETV/CPC patients, corrected age < 2.5 months (p = 0.031), prior CSF diversion (p = 0.001), preoperative FOHR > 0.613 (p = 0.011), and excessive intraoperative bleeding (p = 0.001) independently predicted ultimate conversion to VPS. The actual VPS insertion rates remained low in patients who were ≥ 2.5 months old at ETV/CPC either with prior CSF diversion (2/10 [20.0%]) or without prior CSF diversion (24/123 [19.5%]); however, the actual VPS insertion rates increased in patients who were < 2.5 months old at ETV/CPC with prior CSF diversion (19/26 [73.1%]) or without prior CSF diversion (44/107 [41.1%]). CONCLUSIONS: ETV/CPC successfully treated hydrocephalus in most patients younger than 1 year irrespective of etiology, averting observed shunt dependence in 80% of patients ≥ 2.5 months of age regardless of prior CSF diversion and in 59% of those < 2.5 months of age without prior CSF diversion. For infants aged < 2.5 months with prior CSF diversion, particularly those with severe ventriculomegaly, ETV/CPC was unlikely to succeed unless safely delayed.

Morning glory disc anomaly and its implications in moyamoya arteriopathy: a retrospective case series.

OBJECTIVE: Morning glory disc anomaly (MGDA), a congenital abnormality of the optic nerve, may be associated with moyamoya arteriopathy, a cerebrovascular abnormality. In this study, the authors aimed to define the temporal evolution of cerebrovascular arteriopathy in patients with MGDA to characterize a rational strategy for screening and management over time. METHODS: The records of pediatric neurosurgical patients at two academic institutions were retrospectively reviewed to identify cases of cerebral arteriopathy and MGDA, including radiographic and clinical records documenting patient outcomes of medical and surgical management. RESULTS: Thirteen cases of moyamoya syndrome (MMS) associated with MGDA were identified in 13 children aged 0.6-17 years. The pattern of arteriopathy resembled that of non-MGDA MMS, with predominantly anterior circulation involvement. The arteriopathy lateralized with the MGDA, although 3 patients also had contralateral involvement. The overall group was followed for a median of 3.2 years. Radiological biomarkers of cerebral ischemia were applied to guide surgical decisions, and more than half of the patients (7 of 13) had evidence of stroke or progression on serial imaging. Nine patients underwent revascularization surgery, and 4 were managed medically. CONCLUSIONS: Cerebral arteriopathy observed in association with MGDA resembles MMS seen in patients without MGDA and is dynamic, with progression observed over months to years and an associated risk of cerebral ischemia that indicates a role for surgical revascularization. Radiological biomarkers may augment clinical data to identify candidates for revascularization surgery.

Endoscopic strip craniectomy with orthotic helmeting for safe improvement of head growth in children with Apert syndrome.

OBJECTIVE: Bilateral coronal craniosynostosis in Apert syndrome is traditionally managed with open cranial vault remodeling procedures like fronto-orbital advancement (FOA). However, as minimally invasive procedures gain popularity, limited data exist to determine their efficacy in this syndromic population. This study examines whether endoscopic strip craniectomy (ESC) is inferior to FOA in correcting head growth in patients with Apert syndrome. METHODS: The authors conducted a retrospective review of children with Apert syndrome over a 23-year period. Postoperative head circumferences until 24 months of age were compared for patients treated with ESC versus FOA by using normative growth curves. Intraoperative and postoperative morbidity was compared between groups. RESULTS: The median postoperative follow-up for the FOA (n = 14) and ESC (n = 16) groups was 40 and 28.5 months, the median age at operation was 12.8 and 2.7 months, and the median operative time was 285 and 65 minutes, respectively (p < 0.001). The FOA group had significantly higher rates of blood transfusion, ICU admission, and longer hospital length of stay (p < 0.01). There were no statistically significant differences in premature reossification rates, complications, need for further procedures, or complaints of asymmetry. Compared to normative growth curves, all patients in both groups had head circumferences comparable to or above the 85th percentile at last follow-up. CONCLUSIONS: Children with Apert syndrome and bilateral coronal craniosynostosis treated with ESC experience early normalization of head growth and cephalic index that is not inferior to those treated with FOA. Longer-term assessments are needed to determine long-term aesthetic results and the correlation between head growth and neurocognitive development in this population.

Craniosynostosis of the Metopic Suture in a Patient With CADASIL/Lehman Syndrome.

ABSTRACT: A 3-month-old patient presented for evaluation by plastic surgery with marked trigonocephaly and was subsequently diagnosed with metopic craniosynostosis. During presurgical evaluation, the patient was found to have two variants of the NOTCH3 gene, resulting in the diagnosis of lateral meningocele (Lehman) syndrome. Due to the increased possibility of stroke associated with cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy, the patient underwent only anterior calvarial vault remodeling without fronto-orbital advancement for correction of her craniosynostosis. This unique constellation of symptoms, and its impact on operative management, has not been previously described in the literature.

Analysis of 2141 pediatric craniopharyngioma admissions in the USA utilizing the Kids' Inpatient Database (KID): predictors of discharge disposition.

OBJECTIVES: To recognize the national trends in management of pediatric craniopharyngioma and to address the significant predictors of discharge disposition. METHODS: We utilized the Kids' Inpatient Database (KID), a pediatric inpatient sample generated by the Healthcare Cost and Utilization Project (HCUP) triennially from 1997 to 2016. RESULTS: KID contains 2141 pediatric craniopharyngioma admissions. Patient demographics had no effect on discharge disposition. Based on the multivariable logistic regression analysis, we confirmed a significantly higher non-routine discharge rate among patients with hydrocephalus (P = 0.01). Patients who developed diabetes insipidus were at higher risk for non-routine discharge (P = 0.02). Admission of patients to a freestanding children's hospital increased the likelihood of routine discharge (P = 0.001). CONCLUSION: Hydrocephalus, diabetes insipidus, and admission to a freestanding children's hospital are significant independent predictors of discharge disposition.

Comparative analysis of cranial vault remodeling versus endoscopic suturectomy in the treatment of unilateral lambdoid craniosynostosis.

OBJECTIVE: Unilateral lambdoid synostosis is the premature fusion of a lambdoid suture or sutures and represents the least common form of craniosynostosis, occurring in 1 in 40,000 births. Cranial vault remodeling (CVR) and endoscopic suturectomy with helmet therapy (ES) are surgical approaches that are used to allow for normal brain growth and improved craniofacial symmetry. The authors conducted a comparative outcomes analysis of patients with lambdoid synostosis undergoing either CVR or ES. METHODS: The authors conducted a retrospective consecutive cohort study of patients with nonsyndromic lambdoid synostosis who underwent surgical correction identified from a single-institution database of patients with craniosynostosis seen between 2000 and 2018. Cranial growth was measured in head circumference percentile and z score. RESULTS: Nineteen patients (8 female and 11 male) with isolated unilateral lambdoid synostosis were identified (8 right and 11 left). Six underwent CVR and 13 underwent ES. No statistically significant differences were noted between surgical groups with respect to suture laterality, the patient's sex, and length of follow-up. Patients treated with ES presented and underwent surgery at a younger age than those treated with CVR (p = 0.0002 and p = 0.0001, respectively). Operating and anesthesia time, estimated blood loss, and ICU and total hospital days were significantly lower in ES (all p < 0.05). No significant differences were observed in pre- and postoperative head circumference percentiles or z scores between groups up to 36 months postoperatively. No patients required reoperation as of last follow-up. CONCLUSIONS: Endoscopic management of lambdoid synostosis is safe, efficient, and efficacious in terms of intraoperative and long-term cranial growth outcomes when compared to CVR. The authors recommend this minimally invasive approach as an option for correction of lambdoid synostosis in patients presenting early in their course.

Minimally Invasive Endoscopic Surgery for Infantile Craniosynostosis: A Longitudinal Cohort Study.

OBJECTIVE: To evaluate patient outcomes of minimally invasive endoscopic strip craniectomy (ESC) for craniosynostosis. STUDY DESIGN: This is a retrospective cohort analysis (2004-2018) of 500 consecutive infants with craniosynostosis treated by ESC with orthotic therapy at a single center. Operative outcomes included transfusions, complications, and reoperations as well as head circumference change based on World Health Organization percentiles. Multivariable logistic regression was used to identify risk factors associated with blood transfusion. Paired t tests were used for within-patient comparisons and Fisher exact test to compare syndromic and nonsyndromic subgroups. RESULTS: ESC was associated with low rates of blood transfusion (6.6%), complications (1.4%), and reoperations (3.0%). Risk factors for transfusion included syndromic craniosynostosis (P = .01) and multiple fused sutures (P = .02). Median surgical time was 47 minutes, and hospital length of stay 1 day. Transfusion and reoperation rates were higher among syndromic patients (both P < .001). Head circumference normalized by 12 months of age relative to World Health Organization criteria in infants with sagittal, coronal, and multisuture craniosynostosis (all P < .001). CONCLUSIONS: ESC is a safe, effective, and durable correction of infantile craniosynostosis. ESC can achieve head growth normalization with low risks of blood transfusion, complications, or reoperation. Early identification of craniosynostosis in the newborn period and prompt referral by pediatricians allows families the option of ESC vs larger and riskier open reconstruction procedures.

Results of more than 20 years of follow-up in pediatric patients with moyamoya disease undergoing pial synangiosis.

OBJECTIVEThere are limited data on the long-term outcomes for children undergoing surgical revascularization for moyamoya disease (MMD) in North America. The authors present a series of pediatric MMD patients who underwent a standard revascularization procedure, pial synangiosis, more than 20 years previously at a single institution by a single surgical team.METHODSThis study is a retrospective review of all patients aged 21 years or younger treated for MMD at Boston Children's Hospital who were operated on more than 20 years previously by the senior author (R.M.S.). Radiographic and operative reports, outpatient clinical records, and communications with patients and families were reviewed to document current clinical status, ability to perform daily activities, and concurrent or new medical conditions.RESULTSA total of 59 patients (38 female [64.4%], 21 male [35.6%]; median age at surgery 6.2 years [IQR 0.5-21 years]) were identified who were diagnosed with MMD and underwent surgical revascularization procedures more than 20 years previously. Clinically, all but 2 patients (96.6%) presented with the following symptoms alone or in combination: 43 (73%) presented with stroke, 22 (37%) with transient ischemic attack, 12 (20%) with seizures, 7 (12%) with headache, 3 (5%) with choreiform movements, and 2 (3%) with hemorrhage; MMD was incidentally detected in 2 patients (3%). Five patients had unilateral MMD at presentation, but 3 of these ultimately progressed to develop bilateral MMD after an average of 16 months; therefore, pial synangiosis was ultimately performed in a total of 116 hemispheres during the study period. Clinical follow-up was available at a median interval of 20.6 years (IQR 16.1-23.2 years). Modified Rankin Scale scores were stable or improved in 43 of 50 patients with evaluable data; 45 of 55 are currently independent. There were 6 patient deaths (10.2%; 3 due to intracranial hemorrhage, 2 due to tumor-related complications, and 1 due to pulmonary artery stenosis), 4 of whom had a history of previous cranial radiation. One patient (1.7%) experienced a late stroke. Synangiosis vessels remained patent on all available late MRI and MRA studies. Four patients reported uneventful pregnancies and vaginal deliveries years following their revascularization procedures.CONCLUSIONSRevascularization for MMD by pial synangiosis appears to confer protection from stroke for pediatric patients over long-term follow-up. A history of cranial radiation was present in 4 of the 5 patients who died and in the lone patient with late stroke. Most patients can expect productive, independent lives following revascularization surgery in the absence of significant preoperative neurological deficits and comorbidities.

General Principles for Pial Synangiosis in Pediatric Moyamoya Patients: 2-Dimensional Operative Video.

Pial synangiosis is a method of indirect surgical revascularization developed at our institution for the treatment of moyamoya disease in pediatric patients. Similar surgical principles are employed in adult cases, often performed because of lack of an adequate donor vessel. Standardized protocols, including preadmission for preoperative intravenous hydration and aspirin administration, as well as intraoperative electroencephalography, are routinely employed to minimize operative risk. Perioperative heparinization is not required. The patient is positioned supine, without skull fixation, and the parietal branch of the superficial temporal artery is mapped with Doppler ultrasonography. The artery is microscopically dissected from distal to proximal, leaving a cuff of tissue around the vessel and elevated from the temporalis. The microscope is then removed, the temporalis is opened in a cruciate fashion, and a generous craniotomy is performed, with care to drill away from the exposed artery. The dura is then opened widely (preserving dural collateral vessels), followed by microscopic opening of the arachnoid in as many areas as possible. The donor vessel is then sutured to the pia with 10-0 nylons. The dural leaflets are laid on the brain (without suturing). Closure is completed with saline-soaked gelfoam, with fixation of the bone flap, and muscle reapproximation in the horizontal plane. The galea is closed, followed by the use of resorbable skin suture in pediatric patients. If indicated, the second hemisphere may be performed under the same anesthetic, reducing anesthetic risks and avoiding delayed revascularization. Postoperatively, the patient is awakened and transferred to the intensive care unit.

Clinical status and evolution in moyamoya: which angiographic findings correlate?

Moyamoya is a progressive steno-occlusive cerebrovascular pathology of unknown aetiology that usually involves the terminal portions of the internal carotid arteries and/or the proximal portions of the anterior and middle cerebral arteries bilaterally. The pre-operative Suzuki staging system and post-operative Matsushima grade are nearly universally used markers of natural history and surgical revascularization results, respectively, but their correlation with clinical and radiographic manifestations of moyamoya has not been systematically evaluated in a large cohort. This study evaluated the strength of correlations between pre- and post-operative angiographic parameters and clinical status among paediatric patients with moyamoya. The participants included 58 patients of mean age 11 years at the time of surgery who underwent bilateral indirect revascularization in the same procedure at Boston Children's Hospital, between January 2010 and December 2015. All included patients had available pre-operative and 1-year post-operative digital subtraction angiography. Clinical data included presenting symptoms, degree of functional incapacity, and peri-operative and long-term complications. Radiographic data included pre-operative Suzuki stage, degree of arterial stenosis, a novel collateral score, the presence of hypovascular territories on digital subtraction angiography, and post-operative Matsushima grade and evolution of stenosis. Chi-squared test and Pearson coefficient were used for correlation studies for categorical variables and Spearman's rho was used for correlation studies for continuous variables. Results showed that Suzuki stage, collateral score and degree of stenosis were insufficient to predict clinical presentation, pre-operative incapacity and radiographic presentation, whereas the presence of hypovascular territories was correlated with all of these. At 1-year follow-up, Matsushima grade was insufficient for predicting peri-operative or long-term complications, nor did it correlate with post-operative incapacity. The presence of hypovascular territories at 1-year follow-up was correlated with the incidence of post-operative ischaemic symptoms.

General Principles for Preoperative Planning and Microsurgical Treatment of Pediatric Brain Arteriovenous Malformations: 2-Dimensional Operative Video.

Children with arteriovenous malformations (AVMs) are at cumulative, life-long risk of debilitating and fatal intracranial hemorrhage, especially with syndromes such as hereditary hemorrhagic telangiectasia. Cerebral angiography is the gold standard for diagnosis and allows simultaneous adjunctive embolization limiting radiation and contrast exposure and intraoperative blood loss, important in pediatric patients with low blood volume. Microsurgical resection of low-grade AVMs offers cure with minimal morbidity. The plasticity of the pediatric brain may allow resection of AVMs near eloquent regions. Multidisciplinary care offers the best outcomes in these cases. Discussion of the operative plan with all team members at the start of surgery is carried out. Confirmation that blood products are present and that the microscope, additional suction, and surgical clips are available is performed. A generous craniotomy is created, adequately exposing the lesion. The dura is carefully opened to avoid injury to draining veins. Circumferential dissection and isolation of the AVM is performed, coagulating small arterial feeders, dissecting to the lesion's apex to coagulate, and divide major deep feeders. Once all feeders have been obliterated, venous drainage is disconnected. Indocyanine green distinguishes arterial feeders from arterialized veins and confirms complete resection. Since 2008, all of our patients undergo perioperative angiography in our dedicated suite, greatly improving resection rates. Strict blood pressure control and close neurological monitoring in the intensive care unit is performed postoperatively. In conclusion, microsurgical resection of AVMs can be performed safely with low rates of morbidity. Protocols for preoperative evaluation and planning appear to improve outcomes. Anonymous video is permitted when done without identifying patient related information.

Fourth ventricle stent placement for treatment of recurrent syringomyelia in patients with type I Chiari malformations.

OBJECTIVEIn patients with syringomyelia and type I Chiari malformation (CM-I) who have required reoperation because of persistent, recurrent, or expanding syrinx, the senior author placed a stent from the fourth ventricle to the cervical subarachnoid space in hopes of promoting circulation of CSF out of the ventricle and away from the central canal of the spinal cord. This study was undertaken to determine the long-term success of this operative stratagem in eliminating the syrinx, as well as to document the complications that occurred following stent placement. The technique utilized for placement of fourth ventricle stents is presented.METHODSThe surgical database of the senior author was reviewed to identify all patients who underwent stent placement at a reexploration of a suboccipital decompression for a CM-I conducted for a recurrent or ineffectively treated syringomyelia. The clinical and radiological data of these patients were analyzed to determine long-term efficacy and complications of the procedure.RESULTSFourteen patients (average age 10.7 ± 5.2 years, range 2.6-20.1 years) were identified who met these inclusion criteria. They each presented with recurrent, residual, or expanding syringomyelia following a prior decompression for a CM-I. The reoperation with stent placement was complicated by late stent dislodgement and recurrence or persistence of the syrinx in 2 patients (14%) and by neurological deficit in 1 patient (7%). There was 1 perioperative CSF leak (7%). In 1 other patient (7%), the stent dislodged after surgery but required no further intervention, as the syrinx remained collapsed. Two patients (14%) required late reoperation for stent replacement when syrinxes recurred. At the most recent imaging follow-up, the stent was positioned appropriately in 12 patients (86%; average follow-up 6.9 years, range 0.5-18.1 years), and the recurrent or residual syrinx was eliminated or reduced in size by 75% or greater in 13 patients (93%).CONCLUSIONSThe placement of a stent from the fourth ventricle to the cervical subarachnoid space was a highly effective treatment for patients with recurrent, residual, or expanding syringomyelia following an initial decompression of an associated CM-I. The sole neurological complication in this series was related to lysis of arachnoid scar rather than stent placement itself, but inability to maintain fixation of the stent in situ led to further surgery to replace the stent in 2 patients.

Acute fatal hemorrhage from previously undiagnosed cerebral arteriovenous malformations in children: a single-center experience.

OBJECTIVE The most significant adverse outcome of intracranial hemorrhage from an arteriovenous malformation (AVM) is death. This study reviews a single-center experience with pediatric AVMs to quantify the incidence and characterize clinical and radiographic factors associated with sudden death from the hemorrhage of previously undiagnosed AVMs in children. METHODS A single-center database review of the period from 2006 to 2017 identified all patients with a first-time intracranial hemorrhage from a previously undiagnosed AVM. Clinical and radiographic data were collected and compared between patients who survived to hospital discharge and those who died at presentation. RESULTS A total of 57 patients (average age 10.8 years, range 0.1-19 years) presented with first-time intracranial hemorrhage from a previously undiagnosed AVM during the study period. Of this group, 7/57 (12%) patients (average age 11.5 years, range 6-16 years) suffered hemorrhages that led directly to their deaths. Compared to the cohort of patients who survived their hemorrhage, patients who died were 4 times more likely to have an AVM in the posterior fossa. No clear pattern of antecedent triggering activity (sports, trauma, etc.) was identified, and 3/7 (43%) experienced cardiac arrest in the prehospital setting. Surviving patients were ultimately treated with resection of the AVM in 42/50 (84%) of cases. CONCLUSIONS Children who present with hemorrhage from a previously undiagnosed intracranial AVM had a 12% chance of sudden death in our single-institution series of pediatric cerebrovascular cases. Clinical triggers of hemorrhage are unpredictable, but subsequent radiographic evidence of a posterior fossa AVM was present in 57% of fatal cases, and all fatal cases were in locations with high risk of potential herniation. These data support a proactive, aggressive approach toward definitive treatment of AVMs in children.

Observation of residual disorder in the centre of amorphous solid water films after pore collapse at 125 K.

The rapid structural re-organisation of porous amorphous solid water, grown to thicknesses in the range 2.5-70 µm by vapour deposition on a copper substrate at 75 K, after heating to 125 K has been found to leave a µm-wide band of residual disorder-for example, nm-sized closed pores-in the centre of the film. This layer was revealed by thinning the film by sublimation and continuously measuring the fraction of 1.5 keV positrons implanted into the film which forms ortho-positronium in the top 150 nm and decays into three gamma photons.

Structural changes in amorphous solid water films on heating to 120-140 K and 150-160 K seen by positronium annihilation spectroscopy.

Changes in the structure of amorphous solid water films, grown by vapour deposition on a copper substrate at 75 K and then held at 120 K for 10 min to effect pore collapse, have been observed in the ranges 122-139 K and 150-162 K using positronium annihilation spectroscopy. It is proposed that the former is associated with the glass transition, with an effective activation energy of 0.266(3) eV. The data for the latter, which exhibit minima suggesting the temporary introduction of molecular disorder, can be processed to yield an effective activation energy of 0.47(2) eV, and are consistent with either a structural reorganization of the crystalline lattice or a relaxation of the amorphous structure mediated by defect migration.