Langerhans cell histiocytosis with aneurysmal bone cyst-like changes: a case-based literature review.

BACKGROUND: Langerhans cell histiocytosis (LCH) is a neoplastic transformation of myeloid precursors that commonly presents as an osteolytic lesion of the long or flat bones in children. Aneurysmal bone cysts (ABC) are benign neoplasms that frequently affect the metaphysis of long bones and the spine, often revealing a rapidly expansile lesion with fluid-fluid levels. LCH with secondary ABC-like changes is a rare condition that has only been reported five times, with two presentations in the cranium. The aim of this paper is to review the etiology, clinical and radiographic presentations, and treatment of this condition, as well as to present a novel case on the topic. CASE DESCRIPTION: We describe a 5-year-old boy with a rapidly growing head mass and eye pain resulting in a diagnosis of LCH with secondary ABC-like changes. Radiography demonstrated an expansile, lytic lesion of the left parietal bone with fluid-fluid levels. A confirmatory diagnosis was made through histopathology, demonstrating an inflammatory, histiocytic infiltrate staining positive for CD1a, CD68, CD207 (Langerin), and S-100. The lesion was surgically excised, and the patient recovered without any complications. CONCLUSION: We present a novel case of LCH with secondary ABC-like changes managed with surgical excision. While a radiographic workup with multiple imaging modalities is helpful for diagnosis, a thorough immunohistochemical analysis is essential as imaging characteristics are variable and nonspecific. Furthermore, surgical excision should be considered first-line treatment for lesions involving the skull in surgically accessible areas as it is curative, alleviates symptoms, and allows for histopathological diagnosis.

Radical resection of lumbosacral lipomas in children: the Great Ormond Street Hospital experience.

PURPOSE: In 2009, Pang described a radical resection technique for congenital lumbosacral lipomas, with lower long-term symptomatic re-tethering rates compared with partial resections and conservative management, and low surgical morbidity. We adopted this technique in 2011, and aim to describe our first results. METHODS: In this monocentric retrospective audit, we included dorsal, transitional, chaotic, and caudal-type lumbosacral lipomas. Exclusion criteria were previously operated lipomas, pure filar lipomas, and concomitant major congenital anatomical urogenital/gastrointestinal abnormalities. Neuro-uro-orthopaedic status at presentation and at three months, one year and last postoperative follow-up, intraoperative electrophysiology, and extent of resection were collected. RESULTS: From January 2011 to September 2019, 91 patients were operated (median age 2y2m; 63 transitional; 14 caudal; 8 dorsal; 6 chaotic). Preoperatively, 67% were symptomatic. Preoperative and one-year postoperative rates of impaired ambulation (44% to 43%), hypoesthesia (8% to 5%), urodynamic/uroradiological abnormalities (49% to 37%), and foot/ankle deformities (8% to 5%) were comparable, whilst pain improved (25% to 5%) but catheterisation rates increased (21% to 36%). 23/92 (25%) suffered wound-related complications. 2/91 (2%) developed symptomatic re-tethering requiring second surgery. Mean cord/sac ratio was 0.47. 43% had > 20 mm3 residual fat, which improved with increasing surgical experience. CONCLUSION: Radical lipoma resection, guided by intraoperative neuromonitoring, with reconstruction of the neural placode and expansion duraplasty is technically feasible and results in low rates of late deterioration and re-tethering. Lipoma-type and pre-operative status are important outcome predictors. Operative risks are not insignificant. Future studies need to determine appropriate selection criteria for surgery.

Results Following Adoption of a Modified Melbourne Technique of Total Scaphocephaly Correction.

The Melbourne technique was described in 2008 as a novel method for complete correction of scaphocephaly. Since 2015, it has become our operation of choice for children with sagittal synostosis who are too old at presentation for minimally invasive techniques. Our modifications were 2-position (initially supine then prone) technique and undertaking a formal fronto-orbital remodeling to correct forehead contour. Retrospective chart review was used to record demographics, blood transfusion frequency and volumes, operating time, length of stay, clinical outcome, and complications. Eleven underwent modified Melbourne procedure between July 2015 and March 2017; 9 of 11 were male. All had a diagnosis of nonsyndromic sagittal synostosis. Mean age at surgery was 29 months. Mean surgical time was 6 hours. All patients required blood transfusion with a mean volume transfused of 29 mL/kg (range 13-83 mL/kg). For those 5 patients where preoperative and postoperative measurements were available, there was an increase in mean cephalic index (CI) from 0.64 to 0.75. All postoperative patients had a CI of over 0.70. Three-dimensional shape analysis indicated head shape change addressing all phenotypic aspects of scaphocephaly. In the 5 patients in which analysis could be undertaken, the mean intracranial volume increased from 1481 cm preoperatively to 1671 cm postoperatively, a mean increase in intracranial volume of 14%. The postoperative intracranial volume was higher than preoperative in all 5 patients. There were 4 minor and no major complications. Modified Melbourne procedure is safe and effective for the treatment of severe scaphocephaly in sagittal synostosis.

Selective dorsal rhizotomy for hereditary spastic paraparesis in children.

PURPOSE: The aim of this study was to determine the outcomes for children who underwent selective dorsal rhizotomy (SDR) for the treatment of spasticity related to spinal pathology. METHODS: We performed a retrospective review of all cases of SDR at our institution over the last 30 years and identified patients in whom spasticity was attributed to spinal rather than cerebral pathology. We gathered demographic information and recorded functional status and spasticity scores pre-operatively and over long-term follow-up. RESULTS: We identified four patients who underwent SDR for spinal-related spasticity. All four had hereditary spastic paraparesis (HSP). All patients had reduced spasticity in the lower limbs after SDR, which was maintained over long-term follow-up. Two patients had a more severe and progressive subtype of HSP, and both these patients exhibited functional decline despite improvement in tone. CONCLUSIONS: Our findings suggest SDR is a reasonable option to consider for relief of spinal-related spasticity in uncomplicated hereditary spastic paraparesis. However, SDR for the treatment of complicated HSP seems to carry more risks and have a less predictable outcome. Overall, SDR is probably best reserved for pathologies that are relatively stable in their disease course.

Minimizing blood transfusions in the surgical correction of craniosynostosis: a 10-year single-center experience.

INTRODUCTION: Our center previously reported low transfusion rates for craniosynostosis surgery by two experienced neurosurgeons using standard intraoperative techniques and acceptance of low hemoglobin levels. This study evaluated whether low rates were maintained over the last 10 years and if a less experienced neurosurgeon, trained in and practicing in the same environment, could achieve similar outcomes. METHODS: All craniosynostosis operations performed in children between 2004 and 2015 were reviewed retrospectively. Transfusion rates were calculated. Analyses examined the relationship of transfusion to craniosynostosis type, surgical procedure, redo operation, surgeon, and perioperative hemoglobin levels. RESULTS: Two hundred eighteen patients were included: 71 open sagittal, 28 endoscopic-assisted sagittal, 32 unicoronal, 14 bicoronal, 42 metopic, and 31 multisuture. Median age at operation was 9.1 months. Overall transfusion rate was 24 %: 17 % open sagittal, 7 % endoscopic-assisted sagittal, 6 % unicoronal, 21 % bicoronal, 45 % metopic, and 45 % multisuture. The timing of transfusions were 75, 21, and 4 % for intraoperative, postoperative, and both, respectively. Patients not receiving transfusion had a mean lowest hemoglobin of 87 g/l (range 61-111) intraoperatively and 83 g/l (range 58-115) postoperatively. Mean lowest hemoglobin values were significantly lower in those necessitating intraoperative (75 g/l, range 54-102) or postoperative (59 g/l, range 51-71) transfusions. There was no significant difference in transfusion rate between less and more experienced surgeons. There were no cardiovascular complications or mortalities. CONCLUSION: In craniosynostosis surgery, reproducible, long-term low blood transfusion rates were able to be maintained at a single center by careful intraoperative technique and acceptance of low intraoperative and postoperative hemoglobin levels in hemodynamically stable patients. Furthermore, low rates were also achieved by an inexperienced neurosurgeon in the group. This suggests that these results may be achievable by other neurosurgeons, who follow a similar protocol.

Central Nervous System Coccidioidomycosis in Children: A Retrospective Case Series.

BACKGROUND: Published literature on central nervous system (CNS) coccidioidomycosis in children is limited. Here we describe a large case series of pediatric CNS coccidioidomycosis from a tertiary care center in an endemic region. METHOD: This is a retrospective case review of patients ≤21 years old with a diagnosis of CNS coccidioidomycosis from January 1, 2000, to December 31, 2018. RESULTS: Thirty patients (median age 10.8 years) were identified and most (93%) were previously healthy. Fever (90%), headache (70%), vomiting (53%), and fatigue (57%) were the most common presenting clinical manifestations, with focal neurological signs/symptoms present in 14 (47%). The initial serum Coccidioides compliment fixation (CF) titer was ≤ 1:8 in 33%. Most patients had extra-axial brain involvement (83%) and seven (23%) had associated spinal cord disease. Shunt placement was required in 70% and 62% required revision. Fluconazole was the initial treatment in 22 (73%), with treatment failure occurring in 50%. Most patients (77%) stabilized and were maintained on suppressive therapy, 4 (13%) experienced relapses and/or progressive disease, and one (3%) died, while long-term neurological complications occurred in 17%. CONCLUSIONS: CNS coccidioidomycosis is an uncommon and sometimes devastating complication of disseminated coccidioidomycosis. Many patients present with relatively low CF titers and hydrocephalus is common. Fluconazole treatment failures are common, and management remains difficult despite recent advances in therapy. Most patients do well once the disease is stabilized and require lifelong therapy. Newer therapeutic agents are needed.

Molecular characterization of Lal2, an SRK-like gene linked to the S-locus in the wild mustard Leavenworthia alabamica.

Single-locus sporophytic self-incompatibility inhibits inbreeding in many members of the mustard family (Brassicaceae). To investigate the genetics of self-incompatibility in the wild mustard Leavenworthia alabamica, diallel crosses were conducted between full siblings. Patterns of incompatibility were consistent with the action of single-locus sporophytic self-incompatibility. DNA sequences related to S-locus receptor kinase (SRK), the gene involved in self-pollen recognition in mustards, were cloned and sequenced. A single sequence with high identity to SRK and several other groups of sequences (Lal1, Lal2, Lal3, Lal8, and Lal14) were isolated from L. alabamica. We propose that either Lal2 sequences are divergent alleles of SRK or Lal2 is in tight linkage with SRK because (1) Lal2 alleles cosegregate with S-alleles inferred from dialleles in all 97 cases tested in five families; (2) Lal2 sequences are highly diverse at both synonymous and nonsynonymous sites and exhibit patterns of selective constraint similar to those observed at SRK in Brassica and Arabidopsis; and (3) transcripts of one Lal2 allele were detected in leaves and the styles of open flowers, but were most abundant in the stigmas of maturing buds. We discuss the utility of the S-linked polymorphism at Lal2 for studying the evolutionary forces acting on self-incompatibility in Leavenworthia.

Accuracy of robot-assisted versus optical frameless navigated stereoelectroencephalography electrode placement in children.

OBJECTIVE The aim of this study was to compare the accuracy of optical frameless neuronavigation (ON) and robot-assisted (RA) stereoelectroencephalography (SEEG) electrode placement in children, and to identify factors that might increase the risk of misplacement. METHODS The authors undertook a retrospective review of all children who underwent SEEG at their institution. Twenty children were identified who underwent stereotactic placement of a total of 218 electrodes. Six procedures were performed using ON and 14 were placed using a robotic assistant. Placement error was calculated at cortical entry and at the target by calculating the Euclidean distance between the electrode and the planned cortical entry and target points. The Mann-Whitney U-test was used to compare the results for ON and RA placement accuracy. For each electrode placed using robotic assistance, extracranial soft-tissue thickness, bone thickness, and intracranial length were measured. Entry angle of electrode to bone was calculated using stereotactic coordinates. A stepwise linear regression model was used to test for variables that significantly influenced placement error. RESULTS Between 8 and 17 electrodes (median 10 electrodes) were placed per patient. Median target point localization error was 4.5 mm (interquartile range [IQR] 2.8­6.1 mm) for ON and 1.07 mm (IQR 0.71­1.59) for RA placement. Median entry point localization error was 5.5 mm (IQR 4.0­6.4) for ON and 0.71 mm (IQR 0.47­1.03) for RA placement. The difference in accuracy between Stealth-guided (ON) and RA placement was highly significant for both cortical entry point and target (p < 0.0001 for both). Increased soft-tissue thickness and intracranial length reduced accuracy at the target. Increased soft-tissue thickness, bone thickness, and younger age reduced accuracy at entry. There were no complications. CONCLUSIONS RA stereotactic electrode placement is highly accurate and is significantly more accurate than ON. Larger safety margins away from vascular structures should be used when placing deep electrodes in young children and for trajectories that pass through thicker soft tissues such as the temporal region. ABBREVIATIONS CTA = CT angiography; IQR = interquartile range; MEG = magnetoencephalography; ON = optical frameless neuronavigation; RA = robot-assisted; SEEG = stereoelectroencephalography.

Pediatric intracranial abscesses.

Intracranial infections in children are a relatively rare, but potentially severe condition. Because of the potential for rapid deterioration, timely diagnosis and treatment are necessary. These infections are categorized based on their intracranial location: epidural abscess, subdural empyema, and brain abscess. They largely arise from direct extension of adjacent infection, hematogenous seeding, or trauma. Clinical presentations of intracranial infections also vary. However, common signs and symptoms include headache, fever, nausea and vomiting, altered mental status, focal neurologic deficits, and seizures. In general, MRI demonstrates a peripherally enhancing lesion with high signal on diffusion weighted imaging (DWI). Bacterial isolates vary, but most commonly are a single pathogen. Successful treatment requires a multidisciplinary team approach including such modalities as antibiotic therapy and surgical drainage. When possible, open surgical evacuation of the abscess is preferred, however, in cases of deep-seated lesions, or in unstable patients, aspiration has also been performed with good results.

Intracystic interferon-α treatment leads to neurotoxicity in craniopharyngioma: case report.

Craniopharyngioma is a benign, cystic suprasellar tumor that can be treated with intracystic chemotherapy. Interferon-α (IFN-α) has been gaining popularity as an intracystic treatment for craniopharyngioma because of its efficacy and supposed benign neurotoxicity profile. In this case report the authors describe a patient who, while receiving intracystic IFN-α, suffered a neurological event, which was believed to be related to drug leakage outside the cyst. This is the first report of a focal neurological deficit potentially attributable to intracystic IFN-α therapy, highlighting the fact that IFN-α may have neurotoxic effects on the central nervous system. Given this case and the results of a literature review, the authors suggest that a positive leak test is a relative contraindication to intracystic IFN-α treatment.

Array CGH in brain tumors.

Alterations in the copy number of the cancer genome are frequently observed in brain tumors especially gliomas. Some pertinent examples include amplification of the EGFR locus in chromosome 7p and loss of the PTEN locus in 10q in glioblastoma. Meningiomas are often associated with loss of the NF2 locus in 22q. Array CGH or aCGH probes provide a reliable, consistent, and economical method of profiling genome-wide copy number alterations (CNAs) of cancer specimens at fairly robust resolution. This has allowed for the systematic assessment of brain tumors for recurrent genomic CNAs. In addition, recent technical advancements have increased the robustness of this technique to accommodate DNA derived from formalin-fixed paraffin-embedded (FFPE) tissue. Lastly, novel technologies such as next-generation sequencing and multiplex digital gene counting technology such as NanoString will expand the -repertoire of techniques for assessing CNAs in brain tumors.