Targeted head CT reduction for pediatric patients with hydrocephalus and traumatic brain injury: academic center institutional experience as an example of opportunities for further improvement Abstract Purpose Recent studies aim to reduce radiation exposure associated with computed tomography (CT) using rapid-sequence magnetic resonance imaging (MRI). We evaluated imaging modalities used for hydrocephalus and traumatic brain injury (TBI) to identify opportunities for further radiation exposure reduction. Methods Pediatric (≤ 18 years) patients, with either hydrocephalus or TBI receiving a head CT or head MRI from 2009 to 2017, were quantified using ICD9, ICD10, and CPT codes at a large university hospital. The odds ratios of receiving each imaging modality year-to-year and receiving a MRI or CT in a given year with each diagnosis were calculated. Results Beginning in 2015, hydrocephalus patients were more likely to receive a MRI vs CT (p < 0.0001), with likelihood increasing in the following 2 years. TBI patients were more likely to receive a CT than an MRI from 2009 to 2017. There was a smaller overall decrease in CT scans in TBI patients (p < 0.05) than hydrocephalus patients (p < 0.0001) and a larger increase in MRI use in hydrocephalus patients (p < 0.05) than TBI patients (p < 0.05) from 2009 to 2017. Conclusions Use of CT to evaluate hydrocephalus significantly decreased over the last 3-year time period. However, CT use for TBI patients was inconsistent and did not decrease proportionally, potentially representing a belief that CT is more effective than MRI for detecting hemorrhage. There was greater use of MRI as an alternate imaging method in hydrocephalus patients than TBI patients. Head injury remains an area of improvement to decrease pediatric radiation exposure at our institution and may be an area in need of attention more broadly.

Pediatric headache and neuroimaging: experience of two tertiary centers Abstract Introduction Headache is a frequent complaint in children and adolescents. Decision-making for neuroimaging should take into account the cost and the need for sedation in young children. Aim To evaluate the yield of MRI in pediatric headache patients seen in two large tertiary hospitals. Methods Data were retrospectively collected from patient records (n = 613) and neuroimaging reports. Headache was classified according to International Headache Society guidelines. Results There were 346 children with imaging studies (MRI n = 281, CT n = 65). Of patients who had at least one MRI study, 29% demonstrated an abnormal finding. Findings altering the management were obtained in 21 (7%) patients: the majority (n = 17, 80%) had headache for less than 3 months. On the other hand, four patients with headache longer than 3 months (19%) and 12 patients with normal neurological examination (57%) had significant MRI results affecting management. None of the children in whom the diagnosis of migraine could be made on clinical grounds (n = 40) had a significant MRI finding. Conclusion Neuroimaging should be performed selectively in children with headache seen in pediatric neurology clinics, especially in headache of short duration (< 3 months) and features atypical for migraine. A normal neurological examination should not reassure the clinician.

Ventricular shunt complications in patients undergoing posterior vault distraction osteogenesis Abstract Purpose The primary objective of this study is to investigate post-operative morbidity and shunt revision rates of patients with shunt-dependent hydrocephalus (SDH) undergoing posterior vault distraction osteogenesis (PVDO) compared to patients undergoing conventional posterior vault reconstruction (PVR). Methods A retrospective case-controlled cohort analysis of all patients with SDH undergoing PVDO and PVR for syndromic or complex craniosynostosis was performed. Demographic information, perioperative variables, distraction protocols, and shunt-related complications—infection, surgical revision of shunt, increased length of stay (LOS), and readmission within 90 days of surgery—were compared using the appropriate statistical tests. Results Fourteen patients with ventricular shunts who underwent PVDO and eight patients with shunts who underwent PVR were identified. Shunt-related complication rates were significantly higher with PVDO (n = 5) compared to PVR (n = 0), p = 0.0093. Among the five patients who suffered complications, the most common were shunt infection (n = 4), shunt malfunction (n = 4), and wound infections (n = 3). All patients with complications required additional operations for shunt revision and/or replacement; four patients required multiple takebacks for such procedures, with an average of three additional procedures per patient. Conclusions In complex or syndromic craniosynostosis patients who have previously undergone ventricular shunting, PVDO is associated with higher shunt-related complications and need for additional procedures when compared to traditional PVR. While the benefits of PVDO in the treatment of syndromic craniosynostosis are well documented, the risks of PVDO in the face of a VP shunt must be considered. Further investigation into patient-specific risk factors and risk reduction strategies is warranted.

Trihexyphenidyl for treatment of dystonia in ataxia telangiectasia: a case report Abstract Ataxia telangiectasia (AT) is an autosomal recessive multisystem disorder caused by mutations of ATM gene. And dystonia may develop as a late manifestation in typical AT. Here we report a novel homozygous frameshift ATM mutation (c.1402_1403delAA; p. K468Efs*18) in a 10-year-old male. The patient was diagnosed as typical AT according to clinical presentations which included progressive cerebellar ataxia, oculocutaneous telangiectasia, immune deficiency, and cerebellar atrophy. The genetic finding confirmed the diagnosis. Severe dystonia was presented in late stage of this disease. After 3 months of trihexyphenidyl treatment, the frequency of dystonia was reduced significantly. Although dystonia is not uncommon in phenotype spectrum of AT, compared with other symptoms of this syndrome, such as cerebellar ataxia and dysarthria, dystonia can be treated.

Incidence of venous thromboembolism in hospitalized pediatric neurosurgical patients: a retrospective 25-year institutional experience Abstract Purpose Venous thromboembolism (VTE) refers to both deep venous thrombosis (DVT) and pulmonary embolism (PE). The risk of VTE in adult neurosurgical patients is thoroughly studied. However, the incidence and risk of VTE in a comprehensive pediatric neurosurgical population is not well-defined. The available pediatric data consists of reviews of specific high-risk groups, such as trauma, critical care, or cancer patients. This may not be reflective of the entire spectrum of a high-volume pediatric neurosurgery practice. This study was undertaken to analyze the incidence and risk factors of VTE in all hospitalizations evaluated by a pediatric neurosurgery service over a 25-year period. Methods A retrospective review of electronic medical records was performed for 9149 hospitalizations in 6374 unique patients evaluated by the pediatric neurosurgery service at Riley Hospital for Children (Indianapolis, IN, USA) from 1990–2014. During this time period, there was no standardized VTE prevention protocol. The study group included all patients less than 18 years of age. Patients with a known pre-existing VTE or pregnancy were excluded. Results VTE was diagnosed in 20 of the 9149 (0.22%) hospitalizations, in 18 unique patients. All DVTs were diagnosed via Doppler ultrasound and/or computed tomography. Anatomic clot locations included 9 in the upper extremity (0.098% of hospitalizations), 8 in the lower extremity (0.087%), and 4 (0.044%) pulmonary emboli. Ten of the 20 occurred in hospitalizations where the patient underwent surgery, although the need for surgery was not a statistically significant risk factor. Sixteen of the 20 (80%) occurred in patients with at least one form of central venous line (p < 0.00001). There was one VTE-related death (0.01%). Conclusions In all pediatric neurosurgical patients, a VTE was found in 0.22% of hospitalizations over a 25-year span. Statistically significant risk factors for VTE included central venous line placement, paralysis, malignancy, intubation greater than 48 h, and hypercoagulable state.

Childhood medulloblastoma—a single institution’s historical perspective on survival and functional morbidity Abstract Purpose To compare results from a third (1995–2010) cohort of children with medulloblastoma with two previous series (J Neurosurg 86:13–21, 1997; Arch Dis Child 54:200–203, 1979) to analyse the effects of management changes aimed at improving both overall and event-free survivals (OS and EFS) and functional outcomes. Methods Review of neuro-oncology and imaging databases and previously published results. Results There was no statistically significant improvement in the 5-year OS for 104 children diagnosed 1995–2010, 61.5% (95% CI, 52.9, 71.6), compared with 50% of the 80 children presenting 1980–1990 (J Neurosurg 86:13–21, 1997) (difference 11.5%; 95% CI, 2.8, 25.4). Five-year OS for 96 children suitable for risk-stratification was overall 66% (95% CI, 57.9, 75.8); standard risk 77.8% (95% CI, 67.4, 89.7); high risk < 3 years 50.0% (95% CI, 32.3, 77.5); high risk ≥ 3 years 54.5% (95% CI, 37.2, 79.9); 5-year EFS were standard risk 68.5% (95% CI, 57.2, 82.1); high risk < 3 years 40.0% (95% CI, 23.4, 68.4); and high risk ≥ 3 years 36.4% (95% CI, 20.9, 63.2); overall 55.2% (95% CI, 46.1, 66.1). Of 62/63 ≥ 5-year survivor, 9 died later from tumour relapse and 4 from second malignancy. Functional outcomes of 62 of the 63 ≥ 5-year survivors: 67.7% had educational issues requiring remedial input; 18% restricted mobility indoors and outdoors; 59.7% hearing impairment (42% prescribed aids). Conclusions Comparison of this single-institution series with its predecessor found that revised chemotherapy and RT protocols and greater accuracy of risk stratification did not result in statistically significant improvements in either survival or treatment-related functional disability. Extended (> 5-year) follow-up is essential if 20% of late deaths from relapse and second malignancies are not to be overlooked.

The role of intra-operative neuroelectrophysiological monitoring in single-level approach selective dorsal rhizotomy Abstract Objective Selective dorsal rhizotomy via a single-level approach (SL-SDR) to treat spasticity 100% relies on the interpretation of results from the intra-operative neuroelectrophysiological monitoring. The current study is to investigate the role EMG interpretation plays during SL-SDR procedure with regard to the selection of nerve rootlets for partially sectioning in pediatric cases with spastic cerebral palsy (CP). Methods A retrospective study was conducted in pediatric patients with spastic CP undergone our modified rhizotomy protocol-guided SL-SDR from May 2016 to Mar. 2019 in our hospital. Our study focused on intra-operative EMG interpretation and its correlation with pre-op evaluation results, and dorsal rootlet selection difference when data of our intra-operative EMG recordings interpreted using different rhizotomy protocols. Results Clinical and intra-operative neuroelectrophysiological monitoring data of a total of 318 consecutive cases were reviewed, which include 231 boys and 87 girls with 32 hemiplegias, 161 diplegias, and 125 quadriplegias. Age at the time of SL-SDR in those cases was between 3.0–14.0 (5.9 ± 1.9) years. The number of targeted muscle ranged from 2 to 8 over these cases (the muscle in lower limbs with its pre-op muscle tone ≥ 2 grade, Modified Ashworth scale). Among 21,728 nerve rootlets tested (68.3 ± 8.2/case), 6272 (28.9%) were identified sphincter related by our intra-operative neuromonitoring. In the rest of 15,456 (48.6 ± 7.6/case) nerve rootlets which neuromonitoring suggested associated with lower limbs, 11,009 were taken as the dorsal ones (34.6 ± 7.4/case). A total of 3370 (10.6 ± 4.7/case) rootlets matched our rhizotomy criteria with 3061 (9.6 ± 4.1/case) sectioned 50% and 309 (1.0 ± 1.0/case) cut 75%. The rhizotomy ratio (partially transected nerve rootlets/all dorsal rootlets associated with lower limbs in a particular case) was 15.8%, 22.3%, 33.4%, 41.8%, and 45.7% across cases with their pro-op GMFCS level from I to V, respectively. Rootlets required 75% cut had a tendency to increase as well in our cases with their pro-op GMFCS level from I to V, which comprising 1.5%, 4.8%, 8.5%, 14.1%, and 15.2% of all rootlets transected, respectively. The muscle tone of 2068 targeted muscles in these cases at the time of 3 weeks after the SL-SDR was revealed a significant decrease when compared to pre-op (1.7 ± 0.5 vs. 2.7 ± 0.6). Further investigation to compare our rootlet selection with the one guided by the traditional rhizotomy criteria using our intro-operative EMG recordings in 318 cases, revealed that the overlap ratio had a tendency to increase in cases when their pre-op GMFCS level increased (39.5%, 41.3%, 52.2%, 54.1%, and 62.8% in cases with levels I–V, respectively). While our modified rhizotomy protocol successfully identified 2–23 rootlets for sectioning in all of our 318 cases, the traditional rhizotomy protocol failed to distinguish any for cutting in about 20% of cases with their pre-op GMFCS levels I and II. Conclusions The rhizotomy criteria fully rely on the EMG interpretation making intra-operative neuroelectrophysiological monitoring crucial when SDR is performed via a single-level approach. Our modified rhizotomy protocol is feasible, safe, and effective to guide SL-SDR to treat all types of spastic CP cases by decreasing muscle tone in particular spastic muscle groups in their lower limbs. Data of EMG responses during SL-SDR procedure and as well as the clinical outcomes based on their interpretation could help clinicians to further understand how neuronal circuits work in the spinal cord of these patients.

Atlantoaxial dislocation due to os odontoideum in patients with Down’s syndrome: literature review and case reports Abstract Purpose To clarify etiology, clinical features, and diagnostic and treatment options of atlantoaxial dislocation (AAD) due to os odontoideum (OsO) in patients with Down’s syndrome (DS). Methods We described and analyzed three clinical cases of AAD due to OsO in DS patients and reviewed descriptions of similar cases in the scientific sources. Results According to literature review, more than 80% of DS patients with odontoid ossicles had atlantoaxial instability (AAI). AAI in DS patients with OsO is more often manifested in childhood and adolescence, rarely in adults when ligament relaxation is reduced. Some patients had acute clinical manifestation after a minor trauma without any precursors; in some of the cases, neurological deterioration increased during several years. We found that the earlier surgical treatment of AAD due to OsO in DS patients carries the higher recovery potential. Conclusions Most patients with DS and OsO had AAI. The method of appropriate treatment in such cases is a posterior screw fixation. Preoperative halo traction and posterior fusion have proved to be a very useful tool in the treatment of AAD due to OsO in DS patients. Even if irreducibility of the AAD established preoperatively, it should not be an absolute indication for anterior decompression. In such cases, an attempt to reduce the AAD should be made under general anesthesia during posterior fixation.

Leonardo da Vinci and his contribution to our understanding of the lumbosacral plexus

Shunt independence in pediatric hydrocephalus