Seizures as presentation of shunt malfunction: tertiary paediatric neurosurgery experience.

AIM: Patients with a background of cerebrospinal fluid (CSF)-diverting shunts are frequently investigated for shunt malfunction when presenting with seizures. However, there is very limited evidence in the literature regarding the association of seizures and shunt malfunction. We sought to determine the incidence of shunt malfunction in our cohort of shunted paediatric patients presenting with seizures, and the utility of seizures as a marker of shunt malfunction. METHODS: We retrospectively identified all shunted patients presenting with seizures, as well as all patients undergoing shunt revision following a presentation with seizures from our hospital database over a 14-year period from 2009 to 2023. Data gathered included demographics, de novo seizures or change in pattern of seizures, the aetiology of hydrocephalus and the segment of shunt requiring revision. Exclusion criteria included infected cases requiring shunt externalisation. A literature review of all papers discussing seizures as a presentation of shunt malfunction was also carried out. RESULTS: Overall, over a 14-year period of study, 338 shunted patients presented with seizures and were referred as suspected shunt malfunction with 10 having confirmed shunt malfunction requiring revision (2.9%). This group represented 6.2% of 161 cases of shunt revision carried out during the 14-year period of study. Post-haemorrhagic hydrocephalus secondary to prematurity was the commonest aetiology of shunted hydrocephalus presenting with seizures. Out of 10 patients presenting with seizures with shunt malfunction, 4 presented with de novo seizures, while 6 presented with a change in seizure pattern or frequency in already known epileptic patients. Shunt revision surgeries included 5 distal catheter, 2 proximal catheter, 1 proximal catheter-valve, 1 valve only and 1 case of whole shunt change. CONCLUSION: Our data supports that seizures are rare manifestation of shunt malfunction and can present either de novo or with a change in seizure frequency in already-known epileptic patients.

Dens Growth After Surgical Fixation in Children with Morquio-Brailsford Disease.

Mucopolysaccharidosis type IVA is a lysosomal storage disorder caused by a deficiency of the enzyme N-acetyl-galactosamine-6-sulphate sulphatase. Mucopolysaccharidosis type IVA is multisystemic disease with significant spinal involvement and atlantoaxial instability leading to neural compression and significant morbidity. Dens hypoplasia is a common feature of this condition. In this study we demonstrate that after spinal fixation, there is new growth of dens in significant proportion of patients, suggesting atlantoaxial instability as one of the major driving forces of lack of development of dens in this condition.

Retroflexed dens in paediatric Chiari 1 patients and implications: Single centre retrospective study.

INTRODUCTION: Chiari 1 malformation and hind brain hernia can be associated with skull base and craniocervical anomalies. One of the more recently associated anomalies is a retroverted or retroflexed odontoid process or dens. We conducted a retrospective study of our operated symptomatic and conservatively managed asymptomatic Chiari cohort to assess the impact of dens retroflexion on rate of revision or cerebrospinal fluid diversion following primary foramen magnum decompression (FMD). METHODS: We undertook a retrospective study of all foramen magnum decompression (FMD) cases for Chiari type 1 malformation performed over a 15-year period in a single tertiary paediatric neurosurgical unit. For comparison, non-operated asymptomatic Chiari cases were considered as reference cohort. Information gathered included: demographics, age, sex, length of cerebellar tonsils below McRae's line, pB-C2 distance (a line drawn perpendicular to one drawn between the basion and the posterior aspect of the C2 body), angle of retroflexion (angle formed between a line drawn through the odontoid synchondrosis and its intersection with a line drawn from the tip of the odontoid process) and angle of retroversion (angle formed between the line drawn from the base of C2 and its intersection with a line drawn from the tip of the odontoid process). Grade of retroflexion was measured using pre-operative mid-sagittal MR images and classified as grade 0 (> 90°), grade 1 (85°-89°); grade 2 (80°-84°) and grade 3 (< 80°). The rates for redo surgery or need for cerebrospinal fluid (CSF) diversion were obtained from clinical records and compared in the operated and non-operated groups. RESULTS: One hundred twenty-six Chiari 1 patients were included in this study with adequate imaging. Sixty-five patients were in the non-operated asymptomatic cohort with 61 patients in the operated symptomatic cohort. Mean age of non-operated cohort was 10.2 years with M:F ratio (30:35). Mean cerebellar tonsillar length below McRae's line was 10.3 mm. 7.7% of this cohort had associated syrinx. Mean angles of retroversion and retroflexion were 76 and 78°, respectively. Retroflexion grades included (9.2% grade 1, 35% grade 2 and 52.3% grade 3). pB-C2 distance was 6.8 mm. Mean age of operated cohort was 11.3 years, with M:F ratio (21:40). Mean cerebellar tonsillar length below McRae's line was 15 mm. 45.9% of this cohort had associated syrinx. Mean angles of retroversion and retroflexion were 73 and 74.5°, respectively. Retroflexion grades included (4.9% grade 1, 16.5% grade 2 and 78.6% grade 3). pB-C2 distance was 6.9 mm. No association was identified between retroflexion grade and rate of revision or CSF diversion following primary foramen magnum decompression. CONCLUSION: The operated Chiari 1 cohort had more retroflexed dens, longer tonsils and associated syrinx compared to the non-operated asymptomatic cohort.

Papilloedema: a highly specific predictor of raised intracranial pressure in a complex neurosurgical paediatric cohort.

PURPOSE: Papilloedema is recognised as an indicator of raised intracranial pressure, although there is a paucity of literature describing the utility of fundoscopy in screening for raised ICP in children with craniofacial synostosis, particularly young children. We sought to investigate the association of optic disc morphology with ICP in children, and to define the sensitivity and specificity of papilloedema as a clinical indicator of raised ICP and determine if age, or underlying conditions impact the findings. METHOD: Retrospective analysis of all patients undergoing ICP monitoring at a designated paediatric neurosurgical and craniofacial unit in the United Kingdom between October 2009 and October 2018. The fundoscopy findings and ICP monitoring data were analysed for 31 children with craniosynostosis and 29 children without craniosynostosis. RESULTS: All children who had papilloedema had raised ICP confirmed with monitoring. Across the 60-patient cohort, confirmed papilloedema on fundoscopy had Positive Predictive Value (PPV) of 1.00, Negative Predictive Value (NPV) of 0.64 with sensitivity 48% and specificity 100% for the presence of raised ICP (p = < 0.0001). In the craniosynostosis group, PPV was 1.00, NPV was 0.39, sensitivity 48% and specificity 100% (p = < 0.03). There is no correlation between severity of optic disc swelling using Frisen grading and elevation of ICP. Age did not affect the presence of papilloedema in those with raised ICP. CONCLUSION: The presence of papilloedema is a strong indicator of raised ICP in a child, regardless of underlying aetiology. Detailed fundoscopy can prevent the need for further investigations including imaging-related radiation and invasive CSF pressure monitoring.

Endoscopic third ventriculostomy for hydrocephalus after craniovertebral decompression for Chiari malformation type I: technical nuances and surgical pitfalls.

PURPOSE: Hydrocephalus after craniovertebral decompression (CVD) for Chiari I malformation (CM-1) is a well-recognised complication. The mainstay of management involves medical management with high-dose steroids and/or acetazolamide, repeated lumbar punctures, external ventricular drainage (EVD) or insertion of a ventriculoperitoneal shunt (VPS). Endoscopic third ventriculostomy (ETV) has only been used a handful of times to treat this type of hydrocephalus with controversial outcomes. Not much is known about this or the technical nuances of this procedure. We report our experience. METHODS: All children who underwent ETV to treat hydrocephalus post CVD done for CM-1 were identified from a prospectively kept database. RESULTS: Three children were identified (13F, 11F, 13F). The average time to presentation of hydrocephalus was 8 days after craniovertebral decompression. Two were successfully treated with ETV with brain imaging showing a reduction in the size of the ventricles post-operatively and not requiring any further cerebrospinal fluid drainage. In one patient, the procedure had to be abandoned after the peel away catheter was introduced into the right ventricle because CSF egressed under high pressure with ventricle walls collapse resulting in an obstructed view. This child ultimately required a VPS. CONCLUSION: ETV can be used to successfully treat post CVD hydrocephalus in CM-1 patients depending on the aetiology of the hydrocephalus. There are technical and anatomical commonalities between these cases which make it more challenging than an ETV performed in "typical" obstructive hydrocephalus. We describe our experience and review the cases previously reported in the literature.

Trampoline-Associated Cranial and Spinal Injuries: A 10-Year Study in a Pediatric Neurosurgery Center.

OBJECTIVE:  There has been an increasing use of trampolines for recreation by children in recent years. Many studies have explored the different types of injuries sustained due to falls from trampolines, but so far none have focused specifically on cranial and spinal injuries. In this study, we describe the pattern of cranial and spinal injuries sustained by pediatric patients that were associated with the use of trampolines and their management in a tertiary pediatric neurosurgery unit over a period of 10 years. METHODS:  This is a retrospective study of all children less than 16 years of age with suspected or confirmed trampoline-associated cranial or spinal injuries, managed by a tertiary pediatric neurosurgery unit from 2010 to 2020. Data collected included the patient's age at the time of injury, gender, neurological deficits, radiological findings, management, and clinical outcome. The data were analyzed to highlight any trends in the pattern of injuries. RESULTS:  A total of 44 patients with a mean age of 8 years (ranging from one year and five months to 15 years and five months) were identified. 52% patients were male. 10 patients (23%) had a reduced Glasgow Coma Scale (GCS) score. In terms of imaging findings, 19 patients (43%) had a radiologically positive head injury, nine (20%) had a craniovertebral junction (CVJ) injury, including the first (C1) and second (C2) cervical vertebrae, and six (14%) had an injury involving other parts of the spine. No patient sustained concurrent head and spinal injuries. Eight (18%) patients had normal radiological findings. Two (5%) had incidental findings on radiology that required subsequent surgery. A total of 31 patients (70%) were managed conservatively. 11 patients (25%) underwent surgery for their trauma, of which seven were cranial. Two further patients underwent surgery for their incidental intracranial diagnoses. One child died from an acute subdural hemorrhage. CONCLUSIONS:  This study is the first to focus on trampoline-associated neurosurgical trauma and report the pattern and severity of cranial and spinal injuries. Younger children (less than five years of age) are more likely to develop a head injury, whereas older children (more than 11 years of age) are more likely to develop a spinal injury following the use of a trampoline. Although uncommon, some injuries are severe and require surgical intervention. Therefore, trampolines should be used prudently with the appropriate safety precautions and measures.

Endoscopic fenestration of the superior medullary velum for the treatment of a trapped fourth ventricle-technical note.

A trapped fourth ventricle is a clinic-radiological entity characterised by progressive neurological symptoms due to an enlargement of the fourth ventricle secondary to obstruction to its outflow. This condition is most commonly observed in ex-preterm patients shunted for a post-haemorrhagic or post-infective hydrocephalus. Until the introduction of endoscopic aqueductoplasty and stent placement, through a supratentorial or an infratentorial approach, treatment of trapped fourth ventricle entailed high rates of complications, repeated procedures and consequent morbidity. We describe the first case of successful treatment of trapped fourth ventricle by fenestration of superior medullary velum through an infratentorial approach in a 20-month-old child with a functional supratentorial ventriculoperitoneal shunt and an aqueductal anatomy not favourable for stenting. To the best of our knowledge, this is the first reported case of utilisation of this technique in a patient with a trapped fourth ventricle, and we wish to highlight this new alternative approach in cases where conventional aqueductoplasty and stenting may not be feasible.

Clinical features and outcome in pediatric arteriovenous malformation: institutional multimodality treatment.

PURPOSE: Intracranial arteriovenous-malformation (AVM) is a relatively rare condition in pediatrics, yet is a major cause of spontaneous intracranial hemorrhage with a risk of fatal hemorrhage reported to be between 4 and 29%. Little is known about vessel morphology and optimum treatment modalities including multimodality combination therapy and prognosis in children. METHODS: A retrospective review of all children presenting to our institution from 2006 to 2020 that had an AVM was undertaken. RESULTS: A total of 50 children were identified with median age of 11 (range 1-16) years. The mean follow-up was 7.6 years. Forty-one children presented as an emergency and of those, 40 had hemorrhage identified on initial brain imaging. The average nidus size was 25 mm, drainage was superficial in 51% of cases, and located in eloquent cortex in 56%. The supplemental Spetzler-Martin grading indicated 78% (39/50) were grade 4 and above (moderate to high risk). Primary treatment modalities included embolization in 50% (25) or SRS in 30% (15) and surgery in 20% (10).The AVM was obliterated on follow-up DSA in 66% children. Three children had post-treatment hemorrhage, two related to embolization and one the day following SRS, giving a re-bleed rate of 6%. The GOSE was available for 32 children at long term follow and 94% had a good outcome (GOSE 5-8). Two children died due to acute hemorrhage (4%). CONCLUSION: The majority of children with AVM present with hemorrhage. The rebleed rate during definitive treatment is low at 6% over the study period. The selective use of the 3 modalities of treatment has significantly reduced mortality and severe disability.

The role of surgery in relieving calcified shunt site-related pain in patients with functioning VP shunt.

PURPOSE: Shunt calcification is a known late sequela of ventriculoperitoneal (VP) shunt insertion and is associated with shunt malfunction. However, in some patients, while shunt functionality is preserved despite calcification of the catheters, they experience nociceptive symptoms. In this paper, the authors present their surgical experience in managing patients with a functional VP shunt and experiencing pain secondary to shunt calcification. METHODS: We analysed outcomes of patients presenting with pain at the level of a calcified shunt who underwent surgical untethering of the calcified catheter from the soft tissues. This procedure was commenced by the senior author in 2015. Patients were collected prospectively from the databases of two institutions. Evidence of shunt calcification was confirmed on neuroimaging. RESULTS: Seven patients, two male and five female, were included. The mean age at untethering was 13.5 years. The mean time interval between primary shunt surgery and symptom onset was 12 years (range 6-16 years). The commonest site of tethering was the neck (50%) followed by abdomen and chest (both 25%). Six patients underwent untethering of the catheter from soft tissues. One patient had removal of a redundant segment of calcified shunt left in situ during a previous revision. All patients experienced pain relief following shunt untethering. CONCLUSION: Untethering of calcified VP shunt catheters from soft tissue can be considered an effective treatment of shunt site pain and offered to patients presenting with a functional VP shunt.

ERF-related craniosynostosis and surgical management in the paediatric cohort.

INTRODUCTION: ERF mutation is one of the most recently identified genetic aberrations associated with syndromic craniosynostosis. Data on the pattern of craniosynostosis, surgical management of ERF-related craniosynostosis and outcomes is limited. We report on our single-centre experience in paediatric cohort of patients with syndromic craniosynostosis secondary to ERF mutation. METHODS: A retrospective review of all paediatric craniofacial cases was performed over an 8-year period (2014-2022). All patients with genetically confirm ERF-related craniosynostosis were identified, and clinical parameters including, age, sex, pattern of craniosynostosis, associated tonsillar herniation and follow-up period were further analysed from electronic clinical and imaging systems. All patients were selected and discussed in multidisciplinary craniofacial meeting (composed of neurosurgical, maxillofacial, plastics and genetics teams) prior to any surgical intervention. RESULTS: Overall, 10 patients with ERF-related craniosynostosis were identified with a male-to-female ratio of 4:1 with mean age at the time of surgery of 21.6 months with a mean follow-up period of 5.2 years. ERF-confirmed cases led to variable craniosynostosis pattern with multi-sutural synostosis with concurrent sagittal and bilateral lambdoid involvement as the most common pattern (7/10). No patient pre-operatively had evidence of papilloedema on ophthalmological assessment. Eight out of 10 patients had associated low-lying tonsils/hind brain hernia pre-operatively. Eight out of 10 patients required surgery which included 2 fronto-orbital advancement, 3 calvarial remodelling, 2 posterior calvarial remodelling/release and 1 insertion of ventriculoperitoneal shunt. CONCLUSION: Involvement of sagittal and lambdoid sutures is the most common pattern of craniosynostosis. ERF-related craniosynostosis can have variable pattern of suture fusion, and management of each patient requires unique surgical planning and execution based on clinical needs for the optimal outcomes.

Ophthalmological Care of Patients With Craniofacial Disorders.

Patients presenting with craniofacial conditions present a unique challenge from an ophthalmological view point. There are no set guidelines as to their management or their long-term monitoring and follow-up. Largely, this should be the remit of a dedicated craniofacial team. Here we present pertinent ophthalmological pathology occurring in combination with craniosynostosis alongside the protocol employed in Birmingham Children's Hospital for the management of these patients.

Posterior Calvarial Distraction in older paediatric population: single centre paediatric neurosurgery craniofacial unit outcomes.

PURPOSE: Posterior calvarial distraction (PCD) is a safe and effective technique used to increase cranial vault volume and therefore reduce intracranial pressure in children with complex craniosynostosis. Optimal timing and method used for PCD is controversial. This procedure is usually performed in children younger than 2 years. Literature regarding calvarial distraction in older children is sparse and limited. We report our single-centre experience with PCD in children aged 6 and above to outline the applications, benefits and challenges of employing this technique in an older paediatric population. METHODS: A retrospective analysis of a database on craniofacial cases from 2006 to 2021 was performed. Patients undergoing PCD were identified and children aged 6 and above at the time of operation were included. Data on demographics and clinical outcomes were obtained from electronic records and relevant imaging was reviewed. All cases were reviewed prior to a decision for surgery by the multidisciplinary craniofacial team (composed of neurosurgery, maxillofacial and plastics teams) and underwent surgery in our paediatric craniofacial centre. RESULTS: Overall, 98 PCD cases were identified during the study period, of which 20 cases were identified as having undergone PCD at age 6 or above with mean age of 8.8 years (range 6-18). The most common indication was pansynostosis associated with raised intracranial pressure. Four cases had calvarial remodelling previously and represented with symptoms of raised intracranial pressure sometime after their initial surgery requiring PCD as rescue procedure. Average duration of inpatient stay was 5.85 days. The average duration of follow-up was 3.5 years (0.3 to 11 years). Mean distraction distance achieved was 22.5 mm (18-29 mm). Five patients experienced complications related to wound infection or distractor. Follow-up assessment in all patients demonstrated evidence of vault expansion and symptomatic improvement and resolution of intracranial pressure signs. Comparison with younger cohort did not reveal any difference in any parameters except lower rate of transfusion in the older cohort compared to young cohort (5% vs 38%). CONCLUSION: Posterior calvarial distraction in older children is safe and effective for vault expansion and treatment of raised intracranial pressure in selected cases. A multidisciplinary craniofacial team approach is crucial for appropriate case selection and management in order to optimise outcomes.

A rare case of inferior vena cava occlusion secondary to abdominal pseudocyst associated with ventriculoperitoneal shunt-case report and review of literature.

BACKGROUND AND IMPORTANCE: Abdominal pseudocyst (APC) is an uncommon but well-recognised complication of ventriculo-peritoneal (VP) shunt. Diagnosis is based on clinical features of shunt malfunction, including headaches, vomiting and drowsiness, and abdominal swelling. APCs can grow to large sizes resulting in compression of abdominal viscera; however, inferior vena cava (IVC) compression is extremely rare, and only one other case associated with VP shunt had been reported. CLINICAL PRESENTATION: We report a case of a 12-year-old girl with a background of open myelomeningocoele repair, kyphoscoliosis and right-sided VP shunt in situ who presented with bilateral lower limb swelling and abdominal distension. She exhibited no features of raised intracranial pressure but had bilateral pitting oedema up to the groin. Abdominal ultrasound and CT scan showed a massive septated pseudocyst (20 × 18 × 8 cm) compressing the IVC. The APC was drained, and the shunt was externalised, with conversion to a ventriculo-atrial (VA) shunt 1 week later after cultures of the cystic fluid, cerebrospinal fluid and shunt tube came back sterile. The patient remained well with no recurrence of the abdominal fluid and no VA shunt complication at 36-month follow-up. CONCLUSION: This patient had specific risk factors for development of a massive APC and the subsequent IVC compression, including prior surgeries, spinal deformity, abnormal abdominal anatomy and poor abdominal muscle tone and sensation. Early recognition of this complication and prompt alleviation of the mass effect of IVC compression can prevent long-term neurological and vascular sequalae.

A Simple Method for Eye Protection During Prone Positioning for Craniofacial Surgery.

Surgery in the prone position risks vision loss due to a number of factors. Craniofacial surgery poses an even greater risk due to the anatomical and physiological makeup of these patients. Here, we describe a novel method of providing protection from direct pressure on the globe during prone positioning for craniofacial procedures and our protocol for improving safety and reducing the risk of postoperative vision loss.

Clinical effectiveness of and family experience with telephone consultation in a regional pediatric neurosurgery center in the United Kingdom.

OBJECTIVE: Pediatric neurosurgery outpatient consultation is conducted face-to-face (FTF) conventionally. Reasons for not using telemedicine include the perceived difficulty with obtaining a reliable history and an inability to perform a physical examination. However, FTF consultation can cause distress and inconvenience to the child and family. In 2018, the authors' department piloted a clinical nurse specialist-led telephone consultation (TC) for follow-up appointments. This was extended to the routine neurosurgery clinics in 2020. In this study, the authors evaluate 1) the effectiveness of TC, 2) families' experience with TC compared with traditional FTF appointments, and 3) the factors associated with their preferences. METHODS: In this prospective study using a survey methodology, TCs carried out by 2 consultant neurosurgeons and 1 nurse specialist over 8 weeks were evaluated. Based on clinical background, each patient was assigned to a TC or FTF appointment. Clinical and surgical details and home postal code were recorded. At the end of each TC, the clinician recorded whether the child required an FTF appointment within 3 months. In addition, patients/families answered 1) how the current TC compared with FTF consultation, and 2) their preference of TC or FTF for the next consultation. RESULTS: A total of 114 TCs were included. No child required an FTF appointment within 3 months. Overall, compared with an FTF appointment, the TC was the "same/better/much better" for 101 families (89%), and "worse/much worse" for 13 (11%). Two-thirds of families preferred the next appointment to be a TC. Families attending a TC for new appointments preferred the next appointment to be FTF compared with those attending a follow-up TC (6/8 [75%] vs 31/106 [29%], p = 0.006). A high rating of the current TC was associated with a preference for a TC as the next appointment (p < 0.0001). Families preferring TC over FTF lived farther from the hospital (mean 38 vs 27 km) (p = 0.029). CONCLUSIONS: From the clinicians' perspective, TC is adequate in appropriately selected patients as either the primary mode of consultation or as a triage system. From a service users' perspective, the majority of families felt that the appointment was the same/better than traditional FTF appointments. The findings suggested that 1) new patients should be offered FTF appointments; 2) follow-up TCs should be offered to families when possible; and 3) clinicians should develop their skills in conducting TCs. The authors' results have led to a modification of our algorithm in delivering traditional outpatient service and telemedicine with telephone.

A human importin-ß-related disorder: Syndromic thoracic aortic aneurysm caused by bi-allelic loss-of-function variants in IPO8.

Importin 8, encoded by IPO8, is a ubiquitously expressed member of the importin-ß protein family that translocates cargo molecules such as proteins, RNAs, and ribonucleoprotein complexes into the nucleus in a RanGTP-dependent manner. Current knowledge of the cargoes of importin 8 is limited, but TGF-ß signaling components such as SMAD1-4 have been suggested to be among them. Here, we report that bi-allelic loss-of-function variants in IPO8 cause a syndromic form of thoracic aortic aneurysm (TAA) with clinical overlap with Loeys-Dietz and Shprintzen-Goldberg syndromes. Seven individuals from six unrelated families showed a consistent phenotype with early-onset TAA, motor developmental delay, connective tissue findings, and craniofacial dysmorphic features. A C57BL/6N Ipo8 knockout mouse model recapitulates TAA development from 8-12 weeks onward in both sexes but most prominently shows ascending aorta dilatation with a propensity for dissection in males. Compliance assays suggest augmented passive stiffness of the ascending aorta in male Ipo8-/- mice throughout life. Immunohistological investigation of mutant aortic walls reveals elastic fiber disorganization and fragmentation along with a signature of increased TGF-ß signaling, as evidenced by nuclear pSmad2 accumulation. RT-qPCR assays of the aortic wall in male Ipo8-/- mice demonstrate decreased Smad6/7 and increased Mmp2 and Ccn2 (Ctgf) expression, reinforcing a role for dysregulation of the TGF-ß signaling pathway in TAA development. Because importin 8 is the most downstream TGF-ß-related effector implicated in TAA pathogenesis so far, it offers opportunities for future mechanistic studies and represents a candidate drug target for TAA.

Supratentorial vs infratentorial posterior calvarial distraction osteogenesis for the increase of ICV in children with syndromic or multi-suture craniosynostosis: a retrospective cohort study.

PURPOSE: Craniosynostosis is the premature and pathological fusion of calvarial sutures. One modality of surgical treatment of syndromic craniosynostosis is posterior calvarial distraction (PCD). This can be either supratentorial or infratentorial. Currently, supratentorial PCD may be regarded as safer but produces a smaller increase in calvarial volume compared to infratentorial PCD. This study quantifies and compares the effectiveness of supratentorial and infratentorial PCD to help guide surgical decision-making. METHODS: The CT and/or MRI scans of 47 cases of craniosynostosis who underwent PCD from the Birmingham Children's Hospital (BCH) were converted to sagittal series multi-planar reformatted (MPR) scans for the manual calculation of ICV. The 47 cases were classified as having undergone either supratentorial or infratentorial PCD using lateral plain film radiographs, with 28 and 32 pairs of pre- and post-operative CT/MRI scans reviewed respectively. RESULTS: A statistically significant difference between supratentorial and infratentorial PCD was observed for the increase in supratentorial volume (STV) (P = 0.0458) and total intracranial volume (TICV) (P = 0.0437), but not for the increase in infratentorial volume (ITV) (P = 0.0697). The relationship for each volume trended towards convergence but was not achieved before the physical limit of 30 mm distraction had been reached. Intraclass correlation coefficient values for agreement of MRI and CT scans for STV, ITV and total ICV were 0.852, 0.864 and 0.854 respectively. CONCLUSION: Our evidence suggests that supratentorial PCD is more effective for increasing ICV in a clinical setting. CT and MRI imaging modalities are acceptably clinically interchangeable for calculating ICV in craniosynostosis.

Evaluation and Management of Patients with Hydrocephalus in Craniosynostosis.

BACKGROUND: Hydrocephalus in presence of craniosynostosis, though relatively rare, occurs in 4%-10% cases, with an increased incidence in syndromic craniosynostosis. The optimum management in these patients is unknown. MATERIALS AND METHODS: A search was performed on the departmental craniofacial database to identify all patients with craniosynostosis and hydrocephalus from January 2000 to December 2020. Diagnosis was confirmed by a meticulous review of the notes and previous imaging. These patients were grouped into two groups based on the primary treatment they received: either a cerebrospinal fluid (CSF) diversion procedure or a calvarial remodeling procedure. By analyzing the outcomes for each group, we endeavor to rationalize and outline our management strategy for this complex cohort of patients. RESULTS: Sixty-four of 989 patients were confirmed to have hydrocephalus. Of these, 55 patients underwent calvarial expansion while nine had CSF diversion as a primary procedure. Our study demonstrates that the complication rate is lower in the primary calvarial expansion group. Furthermore, the need for a CSF diversion procedure was avoided in a significant number of these patients as a direct result. CONCLUSION: In the vast majority of patients with craniosynostosis and hydrocephalus, calvarial expansion surgery should be the preferred primary management option.