BACKGROUND: Remifentanil, an ultra-short-acting µ-opioid receptor agonist, is commonly used for anesthetic management due to excellent adjustability. Remifentanil is known to cause sinus bradycardia, however, because it has a direct negative chronotropic effect on the cardiac conduction system and there is an indirect negative chronotropic effect via the parasympathetic nervous system.
METHODS: An 8-year-old Japanese boy was diagnosed with acute hydrocephalus due to a brain tumor in the fourth ventricle and underwent emergency surgery. Imaging examination showed brainstem compression. Endoscopic third ventriculostomy and ventriculoperitoneal shunt surgery were scheduled. Remifentanil was started during induction of general anesthesia, but electrocardiogram showed sinus bradycardia, then Wenckebach-type atrioventricular block, and then complete atrioventricular block. Remifentanil was immediately discontinued, and we administered atropine sulfate. Complete atrioventricular block was restored to sinus rhythm. When remifentanil was restarted, however, the electrocardiogram again showed sinus bradycardia, Wenckebach-type atrioventricular block, and then complete atrioventricular block. Remifentanil was again immediately discontinued, we administered adrenaline, and then complete atrioventricular block was restored to sinus rhythm. Fentanyl was used instead of remifentanil with continuous infusion of dopamine. There has since been no further occurrence of complete atrioventricular block.
CONCLUSIONS: This is the first known case of complete atrioventricular block in a pediatric patient with increased intracranial pressure seemingly caused by administration of remifentanil.

Lhermitte-Duclos disease (LDD), also known as dysplastic cerebellar gangliocytoma, is a rare, slow-growing, benign lesion that occurs in the cerebellum and is very uncommon in the pediatric population. There is a lack of literature and evidence about LDD management, and only one systematic review is available. Thus, more case reports and studies are warranted. This study reports a pediatric case diagnosed with LDD and describes the patient\'s clinical presentation, radiological findings, and histopathological criteria. In addition, important aspects of the disease are discussed to help reach the best management options. The main management option is surgical resection, though a \"wait and see\" approach is also an alternative, especially for asymptomatic patients. More studies are still needed to determine the best management options.

BACKGROUND: Metachronous intracranial germ cell tumors (iGCTs)-unrelated, histologically different iGCTs occurring at different time points-occurring within the same patient remain a rarity. Herein, the authors report such a case and discuss the literature and potential pathophysiological mechanisms leading to this phenomenon.
METHODS: A 9-year-old boy presented with new-onset impaired balance, headaches, nausea, visual disturbances, and left facial paresis. Magnetic resonance imaging (MRI) scans revealed a suspected pineal region teratoma originating from the pineal gland with consecutive obstructive hydrocephalus. A mature teratoma was diagnosed and resected. Postoperative recovery was good, and the patient could return to his normal daily activities. However, a new, slowly progressive lesion in the sellar region with an enlarged infundibular stalk was detected on follow-up MRI 3.5 years after initial pineal region teratoma resection. Biopsy revealed a newly developed pure germinoma. The patient was treated with radiotherapy plus chemotherapy and remained relapse free at the last follow-up. Sixteen other cases have reported a surgically resected primary mature teratoma, wherein patients developed metachronous germinomas during follow-up. Different theories try to elaborate this phenomenon, yet none can completely account for it.
CONCLUSIONS: Although rare, metachronous iGCT is a phenomenon neurosurgeons should be aware of. In patients treated for iGCT, close long-term clinical, imaging, and laboratory follow-up is recommended. https://thejns.org/doi/10.3171/CASE2443.

Pott\'s puffy tumors are assumed to be infrequent concomitant intra- and extracranial abscesses, mainly secondary to complicated frontal sinusitis during infancy. Due to the close proximity to the superior sagittal sinus, there is a risk of developing venous infections, thrombosis, and morbidity. In this case report, we present a case of an 11-year-old girl who presented with headache and face edema. After recognizing the Pott\'s puffy tumor pattern on the CT scan and brain MRI, the neurosurgical approach involved pus evacuation and frontal sinus blockage, and the patient received antibiotic therapy and was evaluated for total recovery. To our knowledge, the prompt diagnosis and treatment of such conditions are paramount to avoid complications, and differential diagnosis should be encouraged in medical practice.

Spasticity is a challenging feature of cerebral palsy (CP) that may be managed with selective dorsal rhizotomy (SDR). Although standard work tools (SWTs) have recently been utilized to inform a standard of care for neurosurgical procedures, no SWTs for SDR have been previously described. The authors present the multidisciplinary approach SWTs for SDR used at their institutions to promote consistency in the field and minimize complication rates.
A multidisciplinary approach was used to define all steps in the SDR pathway. Preoperative, intraoperative, and postoperative workflows were synthesized, with specific efforts to improve mobility through inpatient rehabilitation and minimize infection.
The SWTs have been implemented at two institutions for 7 years. An illustrative case of a patient aged 3 years 10 months with a history of premature birth at 29 weeks, spastic-diplegic CP, right-sided periventricular leukomalacia, and developmental delay who underwent L2-S1 SDR is presented.
The authors detail SWTs for SDR developed by a multidisciplinary team with specific steps at all points in the patient pathway. The illustrative case emphasizes that SWTs may help ensure the safety of SDR while maximizing its long-term efficacy for individuals with CP.

Single-level selective dorsal rhizotomy (SDR), typically indicated for ambulatory patients, is a controversial topic for severe spastic cerebral palsy (CP) with Gross Motor Function Classification System (GMFCS) level IV or V. The objective of this case series and systematic literature review was to outline the indication and outcome of palliative SDR for nonambulatory patients with CP and GMFCS level IV and V, focusing on improvement of spasticity and of patient and caregiver reported quality of life assessment.
A retrospective case series of patients with CP and GMFCS level IV or V who underwent single-level SDR at the authors\' institution is presented. Furthermore, two databases (PubMed and Embase) were searched and a systematic review with a search string based on the terms \"selective dorsal rhizotomy,\" \"cerebral palsy,\" and \"outcome\" was conducted. The primary outcome was the reduction of spasticity based on the modified Ashworth scale (MAS). Secondary outcomes were change on the Gross Motor Function Measure-66 (GMFM-66), evaluation of patient-reported outcome measures (PROMs), surgical morbidity, and mortality.
Eleven consecutive children under the age of 25 years undergoing palliative single-level SDR were included. All patients showed a reduction in MAS score (mean 1.09 ± 0.66 points) and no surgical morbidity and mortality occurred. For the systematic review results from our case series, in addition to 4 reports, 274 total patients were included. Reduction of spasticity based on MAS score was noted in all studies (mean range 1.09-3.2 points). Furthermore, in 2 studies spasticity of the upper extremities showed a MAS score reduction as well (range 1.7-2.8 points). The GMFM-66 score improved in 72% of the patients, while bladder function improved in 78% of the patients. Based on the PROMs, 92% of the patients/caregivers were satisfied with the outcome and their quality of life after the procedure. Two wound infections (2.7%) and one CSF leak (1.3%) occurred, while no surgery-related deaths were described.
This analysis showed an improvement in spasticity, daily care, and comfort for patients with CP and GMFCS levels IV and V. Larger cohorts analyzing the outcome of palliative single-level SDR, based on the MAS, GMFM-66, and PROMs, are still needed and should be the focus of future studies. Systematic review registration no.: CRD42024495762 (https://www.crd.york.ac.uk/prospero/).

BACKGROUND: Unilateral cranial nerve (CN) VI, or abducens nerve, palsy is rare in children and has not been reported in association with Chiari malformation type 1 (CM1) in the absence of other classic CM1 symptoms.
METHODS: A 3-year-old male presented with acute incomitant esotropia consistent with a unilateral, left CN VI palsy and no additional neurological symptoms. Imaging demonstrated CM1 without hydrocephalus or papilledema, as well as an anterior inferior cerebellar artery (AICA) vessel loop in the immediate vicinity of the left abducens nerve. Given the high risk of a skull base approach for direct microvascular decompression of the abducens nerve and the absence of other classic Chiari symptoms, the patient was initially observed. However, as his palsy progressed, he underwent posterior fossa decompression with duraplasty (PFDD), with the aim of restoring global cerebrospinal fluid dynamics and decreasing possible AICA compression of the left abducens nerve. Postoperatively, his symptoms completely resolved.
CONCLUSIONS: In this first reported case of CM1 presenting as a unilateral abducens palsy in a young child, possibly caused by neurovascular compression, the patient\'s symptoms resolved after indirect surgical decompression via PFDD.

Sporadic vestibular schwannomas (VSs) are rare in children. When occurred in the pediatric population, they usually appear bilaterally and are related to neurofibromatosis type 2 (NF2). The current study reports a 4-year-old boy without family history of VS or NF2 who presented with a large (5.7-cm) VS involving the right cerebellopontine angle and internal auditory canal. Through seven-staged surgical interventions and two stereotactic γ‑knife radiosurgery, the disease was stabilized. At 2-year follow-up, the child had right ear hearing loss, grade IV facial palsy, and normal motor function and gait. No definite evidence of gene mutation regarding NF2 can be identified after sequence analysis and deletion/duplication testing. This case highlights the significance of considering the possibility of sporadic VSs, even in very young children. It emphasizes the importance of not overlooking initial symptoms, as they may indicate the presence of a large tumor and could potentially result in delayed diagnosis.

BACKGROUND: Aneurysmal bone cysts (ABCs) are benign, osteolytic lesions that can occur in long bones, vertebrae, or rarely, the skull. Here the authors present the case of a 15-year-old male with a primary ABC of the left frontoparietal skull along with a review of the literature to provide insight into the nature of this rare disease.
METHODS: An otherwise healthy 15-year-old male presented with a tense, painful lesion of the left frontoparietal scalp. He could not identify any inciting trauma, but first noted the lesion less than 2 weeks prior to presentation with progressive enlargement. Cranial imaging revealed a lytic skull lesion with fluid-fluid levels suggestive of ABC. Curative therapy was provided via wide excision of the lesion and calvarial reconstruction of the resultant skull defect. This was performed without complication, and histopathological evaluation confirmed the diagnosis of primary ABC.
CONCLUSIONS: ABCs of the skull are rare entities and most often arise in the skull base versus the calvaria. Typically, these lesions are associated with an underlying bone pathology (secondary ABCs) but can be rarely seen as isolated lesions (primary ABCs). Clinical management consists of excision and adjuvant therapy for underlying pathology where appropriate.

BACKGROUND: Cavernous malformations (CMs), also known as cavernomas or cavernous angiomas, are vascular malformations characterized by sinusoidal spaces lined by endothelial cells. Giant CMs (GCMs) are extremely rare, with limited understanding of their presentation and management. We present a case of symptomatic GCM in a newborn and review the literature on this rare entity.
METHODS: A 1-month-old newborn presented with focal seizures and signs of increased intracranial pressure. Imaging revealed a massive right frontal-parietal GCM, prompting surgical resection. Histopathological examination confirmed the diagnosis of cerebral cavernous malformation. The patient recovered well postoperatively with no neurological deficits.
CONCLUSIONS: GCMs are exceedingly rare in children and have not been reported in newborns until now. Symptoms typically include seizures and mass effects. Gross total resection is the standard treatment, offering favorable outcomes. Further research is needed to understand the natural history and optimal management of GCMs, particularly in newborns, emphasizing the importance of heightened clinical awareness for timely diagnosis and appropriate management.