Ahn, Edward S.

OBJECTIVE Quantitative measurements of trigonocephaly can be used to characterize and track this phenotype, which is associated with metopic craniosynostosis. Traditionally, trigonocephaly metrics were extracted from CT scans; however, this method exposes patients to ionizing radiation. Three-dimensional optical scans are another option but are not routinely available in most outpatient settings. Recently, the authors developed semiautomated artificial intelligence algorithms that extract craniometric data from orthogonal 2D photographs. Although 2D photographs are safe, inexpensive, and straightforward to obtain, the accuracy of photograph-based craniometrics in comparison to CT and 3D optical scan correlates has not been established. In this study the authors compared the classification power of 2D photograph–based metrics of trigonocephaly with four CT-based metrics and one 3D optical scan–based metric in a heterogeneous series of patients who presented to an outpatient craniofacial clinic. METHODS In this study the authors performed retrospective craniometric analyses of patient 2D photographs, 3D optical scans, and CT scans. Imaging-derived craniometrics include the 2D photograph–based anterior arc angle (AAA2D-photo), anterior-posterior ratio (APR2D-photo), and anterior-middle ratio (AMR2D-photo); the CT-based anterior arc angle (AAACT), metopic index (MICT), endocranial-bifrontal angle (eBFACT), and interfrontal angle (IFACT); and the 3D optical scan–based anterior arc angle (AAA3D-optical). Receiver operating characteristics (ROCs) were used to identify craniometrics strongly descriptive of trigonocephaly. Interrater comparisons were made between paired trigonocephaly measurements obtained from photographs and either CT scans or 3D optical scans. RESULTS There were 13 photograph-based and CT-based pairs and 22 paired measurements from 2D photographs and 3D optical scans. AAA displayed the strongest classification capacity across all three imaging modalities. Significant agreement was observed between AAACT and AAA2D-photo (intraclass correlation coefficient [ICC] = 0.68 [95% CI 0.24–0.89], p = 0.0035), and AAA3D-optical and AAA2D-photo (ICC = 0.70 [95% CI 0.41–0.87], p < 0.0001). There was no significant correlation between APR2D-photo or AMR2D-photo and conventional CT-based metrics describing longitudinal width ratios (MICT). CONCLUSIONS Photograph-based craniometrics are powerful tools that can be used to quantify the severity of trigonocephaly and exhibit high concordance with standard measurements derived from CT scans and 3D optical scans. The authors developed and freely share a research-use application to calculate trigonocephaly metrics from 2D photographs. Given the availability of digital photography, lack of ionizing radiation, and low cost of photograph-based craniometric derivation, this technique may be useful to supplement routine ambulatory care and objectively track outcomes following treatment.

BACKGROUND: Chiari I malformation is a common pediatric neurosurgical disorder with an established treatment paradigm. Posterior fossa decompression and duraplasty (PFDD) is associated with symptom improvement but it carries postoperative risk, particularly cerebrospinal fluid (CSF) leak and wound complications. In addition, the cosmetic outcomes of PFDD have been overlooked in the literature. OBJECTIVE: To describe a novel approach for PFDD in which the transverse surgical incision is completely hidden above the hairline and to report early outcomes in a prospective patient cohort. METHODS: Clinical and cosmetic outcomes were recorded for 15 consecutive pediatric patients who underwent PFDD for Chiari I malformation via the above-the-hairline transverse suboccipital approach. RESULTS: The median clinical follow-up time was 6 months (range 1-12 months), and the majority of patients experienced significant improvement of their preoperative symptoms. Three patients (20%) experienced complications associated with surgery, which included injury to the greater occipital nerve, CSF hypotension and subfascial pseudomeningocele, and superficial wound dehiscence that resolved spontaneously with oral antibiotics. Zero patients (0%) returned to the operating room for persistent CSF leak, deep wound infection, or revision decompression. An excellent cosmetic outcome was achieved in 12 patients (80%). No patient had a poor cosmetic outcome. CONCLUSION: The above-the-hairline transverse suboccipital approach for PFDD in patients with Chiari I malformation offers favorable cosmetic outcomes and fascial closure while permitting adequate decompression.

OBJECTIVE Complex tethered spinal cord (cTSC) release in children is often complicated by surgical site infection (SSI). Children undergoing this surgery share many similarities with patients undergoing correction for neuromuscular scoliosis, where high rates of gram-negative and polymicrobial infections have been reported. Similar organisms isolated from SSIs after cTSC release were recently demonstrated in a single-center pilot study. The purpose of this investigation was to determine if these findings are reproducible across a larger, multicenter study. METHODS A multicenter, retrospective chart review including 7 centers was conducted to identify all cases of SSI following cTSC release during a 10-year study period from 2007 to 2017. Demographic information along with specific microbial culture data and antibiotic sensitivities for each cultured organism were collected. RESULTS A total of 44 SSIs were identified from a total of 655 cases, with 78 individual organisms isolated. There was an overall SSI rate of 6.7%, with 43% polymicrobial and 66% containing at least one gram-negative organism. Half of SSIs included an organism that was resistant to cefazolin, whereas only 32% of SSIs were completely susceptible to cefazolin. CONCLUSIONS In this study, gram-negative and polymicrobial infections were responsible for the majority of SSIs following cTSC surgery, with approximately half resistant to cefazolin. Broader gram-negative antibiotic prophylaxis should be considered for this patient population.

OBJECTIVE Arteriovenous malformations (AVMs) are a major cause of intracerebral hemorrhage in children, resulting in significant morbidity and mortality. Moreover, the rate of AVM recurrence in children is significantly higher than in adults. The aim of this study was to define the risk of delayed pediatric AVM (pAVM) recurrence following confirmed radiological obliteration. Further understanding of this risk could inform the role of long-term radiological surveillance. METHODS The authors conducted a retrospective review of ruptured and unruptured pAVM cases treated at a single tertiary care referral center between 1994 and 2019. Demographics, clinical characteristics, treatment modalities, and AVM recurrence were analyzed. RESULTS A total of 102 pediatric patients with intracranial AVMs, including 52 (51%) ruptured cases, were identified. The mean patient age at presentation was 11.2 ± 4.4 years, and 51 (50%) patients were female. The mean nidus size was 2.66 ± 1.44 cm. The most common Spetzler-Martin grades were III (32%) and II (31%). Stereotactic radiosurgery was performed in 69.6% of patients. AVM obliteration was radiologically confirmed in 68 (72.3%) of 94 patients with follow-up imaging, on angiography in 50 (73.5%) patients and on magnetic resonance imaging in 18 (26.5%). AVM recurrence was identified in 1 (2.3%) of 43 patients with long-term surveillance imaging over a mean follow-up of 54.7 ± 38.9 months (range 2–153 months). This recurrence was identified in a boy who had presented with a ruptured AVM and had been surgically treated at 5 years of age. The AVM recurred 54 months after confirmed obliteration on surveillance digital subtraction angiography. Two other cases of presumed AVM recurrence following resection in young children were excluded from recurrence analysis because of incomplete sets of imaging available for review. CONCLUSIONS AVM recurrence following confirmed obliteration on imaging is a rare phenomenon, though it occurs more frequently in the pediatric population. Regular long-term follow-up with dedicated surveillance angiography is recommended even after obliteration following resection.

The authors describe an endoscopic strip craniectomy through a single incision for the treatment of sagittal craniosynostosis in a young infant. The endoscopic strip craniectomy was first introduced with the use of two incisions on either end of the fused suture. This single-incision technique offers several advantages. There is a cosmetic advantage and a reduced risk of wound complications. This technique also allows for early control of emissary veins and an inside-out identification of the lambdoid sutures. Endoscopic visualization is optimized to reduce the risk of blood loss, especially because circulating blood volume is very limited in these young infants. The video can be found here: https://vimeo.com/514366415

OBJECTIVE The authors sought to evaluate the accuracy of a novel telehealth-compatible diagnostic software system for identifying craniosynostosis within a newborn (< 1 year old) population. Agreement with gold standard craniometric diagnostics was also assessed. METHODS Cranial shape classification software accuracy was compared to that of blinded craniofacial specialists using a data set of open-source (n = 40) and retrospectively collected newborn orthogonal top-down cranial images, with or without additional facial views (n = 339), culled between April 1, 2008, and February 29, 2020. Based on image quality, midface visibility, and visibility of the cranial equator, 351 image sets were deemed acceptable. Accuracy, sensitivity, and specificity were calculated for the software versus specialist classification. Software agreement with optical craniometrics was assessed with intraclass correlation coefficients. RESULTS The cranial shape classification software had an accuracy of 93.3% (95% CI 86.8–98.8; p < 0.001), with a sensitivity of 92.0% and specificity of 94.3%. Intraclass correlation coefficients for measurements of the cephalic index and cranial vault asymmetry index compared to optical measurements were 0.95 (95% CI 0.84–0.98; p < 0.001) and 0.67 (95% CI 0.24–0.88; p = 0.003), respectively. CONCLUSIONS These results support the use of image processing–based neonatal cranial deformity classification software for remote screening of nonsyndromic craniosynostosis in a newborn population and as a substitute for optical scanner– or CT-based craniometrics. This work has implications that suggest the potential for the development of software for a mobile platform that would allow for screening by telemedicine or in a primary care setting.

OBJECTIVE Pediatric Chiari I malformation decompression is a common neurosurgical procedure. Liposomal bupivacaine (LB) is a novel formulation that can have an impact on postoperative recovery for particular procedures, but its potential role in pediatric neurosurgery is largely unexplored. The authors sought to describe and assess their initial experience with LB in pediatric Chiari I malformation decompression to better define its potential role as an analgesic agent in a procedure for which the postoperative course is often remarkably painful. METHODS A retrospective review of all pediatric Chiari procedures performed at the authors’ institution between 2018 and 2020 was conducted. Patients were divided into those who were treated with a single intraoperative dose of LB (LB group) and those who were not (control group). Comparisons of total opioid use and pain control were made using chi-square and Wilcoxon rank-sum tests. RESULTS A total of 18 patients were identified, 9 (50%) in the LB group and 9 (50%) in the control group. Overall, there were 13 (72%) female and 5 (28%) male patients with a mean age of 15.9 years. No surgical complications were observed over a mean length of stay of 2.7 days. Within the first 24 hours after surgery, the LB group had significantly lower total opioid use than the control group (17.5 vs 47.9 morphine milligram equivalents, respectively; p = 0.03) as well as lower mean pain scores reported by patients using a 10-point visual analog scale (3.6 vs 5.5 for the LB vs control groups, p = 0.04). However, from the first 24 postoperative hours to discharge, total opioid use (p = 0.51) and mean pain scores (p = 0.09) were statistically comparable between the two groups. There were 2/9 (22%) LB patients versus 0/9 (0%) control patients who did not require opioid analgesia at any point during hospitalization. CONCLUSIONS The use of a single intraoperative dose of LB in pediatric Chiari I malformation surgery appears to be safe and has the potential to reduce pain scores and opioid use when administered during the first 24 postoperative hours. From that time period to discharge, however, there may be no significant difference in total opioid use or pain scores.