Intracranial Empyemas in the COVID-19 Era: A New Phenomenon? A Paediatric Case Series and Review of the Literature.

INTRODUCTION: We present the largest series of paediatric intracranial empyemas occurring after COVID-19 infection to date, and discuss the potential implications of the pandemic on this neurosurgical pathology. METHODS: Patients admitted to our centre between January 2016 and December 2021 with a confirmed radiological diagnosis of intracranial empyema were retrospectively reviewed, excluding non-otorhinological source cases. Patients were grouped according to onset before or after onset of the COVID-19 pandemic and COVID-19 status. A literature review of all post-COVID-19 intracranial empyemas was performed. SPSS v27 was used for statistical analysis. RESULTS: Sixteen patients were diagnosed with intracranial empyema: n = 5 prior to 2020 and n = 11 after, resulting in an average annual incidence of 0.3% prior to onset of the pandemic and 1.2% thereafter. Of those diagnosed since the pandemic, 4 (25%) were confirmed to have COVID-19 on recent PCR test. Time from COVID-19 infection until empyema diagnosis ranged from 15 days to 8 weeks. Mean age for post-COVID-19 cases was 8.5 years (range: 7-10 years) compared to 11 years in non-COVID cases (range: 3-14 years). Streptococcus intermedius was grown in all cases of post-COVID-19 empyema, and 3 of 4 (75%) post-COVID-19 cases developed cerebral sinus thromboses, compared to 3 of 12 (25%) non-COVID-19 cases. All cases were discharged home with no residual deficit. CONCLUSION: Our post-COVID-19 intracranial empyema series demonstrates a greater proportion of cerebral sinus thromboses than non-COVID-19 cases, potentially reflecting the thrombogenic effects of COVID-19. Incidence of intracranial empyema at our centre has increased since the start of the pandemic, causes of which require further investigation and multicentre collaboration.

Patient Tailored Surgery in Saethre-Chotzen Syndrome: Analysis of Reoperation for Intracranial Hypertension.

Saethre-Chotzen syndrome (SCS) is a syndromic craniosynostosis with pathogenic variants in the TWIST1 gene showing a broad phenotypic spectrum. Controversies exist in the literature regarding surgical management with single one-stage versus patient-tailored surgery and the related reoperation rate for intracranial hypertension of up to 42%. At our center, SCS patients are offered patient-tailored surgery with single-stage fronto-orbital advancement and remodeling or fronto-orbital advancement and remodeling and posterior distraction in an individually determined order. The authors' database identified 35 confirmed SCS patients between 1999 and 2022. Involved sutures in craniosynostosis were left unicoronal (22.9%), bicoronal (22.9%), sagittal (8.6%), bicoronal and sagittal (5.7%), right unicoronal (2.9%), bicoronal and metopic (2.9%), bicoronal, sagittal and metopic (2.9%), and bilateral lambdoid (2.9%). There was pansynostosis in 8.6% and no craniosynostosis in 14.3% of the patients. Twenty-six patients, 10 females, and 16 males were operated on. Mean age at the first surgery was 1.70 years, and 3.86 years at the second surgery. Eleven of 26 patients had invasive intracranial pressure monitoring. Three patients presented with papilledema before the first surgery and 4 afterward. Four of the 26 operated patients were operated initially elsewhere. The other 22 patients were initially referred to our unit and underwent patient-tailored surgery. Nine of these patients (41%) had a second surgery, and 3 (14%) of them were because of raised intracranial pressure. Seven (27%) of all operated patients had a complication. Median follow-up was 13.98 years (range, 1.85-18.08). Patient-tailored surgery in a specialized center and long-term follow-up allow for a low reoperation rate for intracranial hypertension.

Non-pharmacological treatment options of drug-resistant epilepsy in subcortical band heterotopia: systematic review and illustrative case.

OBJECTIVE: Subcortical band heterotopia is a rare X-linked neuronal migration disorder primarily in females often associated with drug-resistant epilepsy. The aim of this study is to review the literature for non-pharmacological treatment options of drug-resistant epilepsy in subcortical band heterotopia. MATERIAL AND METHODS: In accordance with the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines, we performed a systematic review. Entering the keywords "double cortex," "subcortical band heterotopia," and "subcortical laminar heterotopia," we searched Scopus and PubMed databases. We paid particular attention to type of invasive and non-invasive treatment, radiological presentation, and outcome. We also describe a related case report, managed at Alder Hey Children's Hospital, Liverpool. RESULTS: The systematic literature review yielded 25 patients with subcortical band heterotopia and drug-resistant epilepsy who underwent non-pharmacological treatment. Including our patient, 26 patients were reported. The patients' mean age at seizure onset was 6.5 years (range 0.2-23) with a female sex predilection (5.25:1). The patients' mean age at invasive or non-invasive treatment was 21.5 years (range 6.5-51). The 26 patients underwent 29 non-pharmacological treatments. Ten patients underwent corpus callosotomy; 8 patients had a formal temporal lobectomy. Three patients had focal cortical resection. Two patients respectively had multiple subpial transections, insertion of a vagal nerve stimulator, or deep brain stimulation of the bilateral anterior nuclei of the thalamus. One patient underwent responsive focal neurostimulation. Another patient had transcutaneous stimulation of the vagal nerve. Sixteen patients reported a reduction or the disappearance of the seizures; 1 patient had no improvement. The outcome of 2 patients was classified class I, of 1 patient class II, of 1 patient class III, and of 5 patients class IV according to the Engel Epilepsy Surgery Outcome Scale. CONCLUSION: Mainly corpus callosotomy and formal temporal lobectomy have been performed as non-pharmacological treatment with few cases published overall. Several other invasive procedures and one non-invasive technique are based on case reports. The small number of reported cases prevents drawing a firm conclusion as to which non-pharmacological treatment is the best treatment option for refractive epilepsy in patients with subcortical band heterotopia.

Postoperative Intracranial Hypotension-Associated Venous Congestion after Spinal Surgery Managed with Multiple Blood Patches: Case Report.

BACKGROUND: Postoperative intracranial hypotension-associated venous congestion (PIHV) is a rare event. The authors report the case of a patient presenting with PIHV after spinal surgery following the sudden loss of cerebrospinal fluid (CSF) induced by suction drainage. METHODS: A 69-year-old patient underwent uneventful revision surgery for wound dehiscence after lumbar surgery with placement of a subfascial suction drain. RESULTS: Postoperatively, the patient presented with fluctuating consciousness and a generalized tonic-clonic seizure. Computed tomography (CT) and serial magnetic resonance imaging (MRI) were performed showing convexity subarachnoid hemorrhages (SAHs), diffuse swelling of the brain and thalami and striatum bilaterally without diffusion restriction, and signs of intracranial hypertension resulting in pseudohypoxic brain swelling in PIHV. A dural leak at L3-L4 was treated with several CT-guided patches combining autologous blood and fibrin glue injections. The patient recovered without neurologic deficit and follow-up MRI revealed progressive complete reversal of brain swelling, and re-expansion of CSF spaces. CONCLUSION: PIHV is a rare but potentially fatal entity. Awareness of PIHV after cranial or spinal surgery leads to early treatment of CSF hypovolemia and possibly better clinical outcome. Following acute CSF volume loss, an acute elevation of cerebral blood volume overcoming autoregulatory mechanisms seems a likely explanation for diffuse cerebral vasogenic edema and SAH in PIHV.

Iatrogenic syringomyelia postcranial surgery in pediatric patients: systematic review and illustrative case.

INTRODUCTION: Iatrogenic syringomyelia has previously been described preoperatively due to space occupying lesions and postoperatively predominantly postspinal CSF drainage. Iatrogenic syringomyelia after cranial surgery is a rare entity. The purpose of this study is to review the current literature for iatrogenic syringomyelia following cranial surgery in children. MATERIAL AND METHODS: We performed a systematic review in accordance with the PRISMA (Preferred Reporting Items for Systematic Reviews and meta-analyses) guidelines. Using keywords "de novo," "acquired," "iatrogenic," "postoperative development," and "syringomyelia," we searched PubMed and Scopus databases. We paid particular attention to type of surgery, clinical presentation, management, and outcome. We also present a relevant case report, operated on at John Radcliffe Hospital, Oxford. RESULTS: The systematic literature review provided 19 cases of iatrogenic syringomyelia postcranial surgery in pediatric patients, in addition to our case report, resulting in a total of 20 cases reported. The patients' mean age at surgery preceding syringomyelia was 8.1 years (range 0.1-17) with a female sex predilection (2.7:1). The mean time of manifestation of the iatrogenic syringomyelia after surgery was 5.7 years (range 0.1-51), and the median time to presentation was 1.7 years. Nine children had surgery for Chiari I malformation before formation of the syrinx, 8 patients underwent shunt surgery, 2 children had intracranial tumor surgery, and 1 patient had lambdoid and sagittal suturectomy for scaphocephaly before developing a syrinx. Surgery after the manifestation of the iatrogenic syrinx resolved the symptoms in 9 patients; in 8 patients, the symptoms partially resolved; and in 1 patient, the symptoms persisted. After surgery addressing the syrinx, it resolved in 5, decreased in size in 10, and remained unchanged in 2 of the patients. CONCLUSION: Iatrogenic syringomyelia after cranial surgery in pediatric patients occurs mainly after decompressive surgery for Chiari I malformation, shunt surgery, and less frequently following intracranial tumor surgery. Risk factors are postoperative intracranial scarring, shunt malfunction, and mass effect on the foramen magnum. Surgery addressing the iatrogenic syrinx seems to be effective in the majority of the patients in terms of clinical and radiological outcome.

Spontaneous transethmoidal meningoencephalocele presenting in the form of recurrent unilateral nasal discharge: discussion of the diagnosis and endoscopic surgical management.

Meningoencephaloceles of the skull base most commonly occur as a sequela of head trauma or they can more rarely be congenital malformations. Several types of encephalocele exist depending on anatomic features and localisation. Clinical presentation and symptoms can vary. Different methods of management and repair of the concurring skull base defects have been described and ranging vary from endoscopic to open surgical approaches. We report the case of a 56-year-old Caucasian woman with the diagnosis of right sided spontaneous transethmoidal meninoencephalocele. Clinical presentation of this rare pathology, methods of diagnostic and management and its outcome are presented. Spontaneous skull base meningoencephaloceles are rare entities, without clear underlying etiologies. Multidisciplinary management is recommended. The transnasal endoscopic approach provides a wide skull base exposure with more advantages and less morbidity in comparison with the conventional open approach.

CSF goes astray no matter what is in the way: occipital intradiploic pseudomeningocele and de novo syringomyelia following foramen magnum decompression for Chiari I malformation in a pediatric patient.

Nontraumatic intradiploic pseudomeningoceles and de novo syringomyelia formation are very rare entities. The authors have previously reported the case of a 4-year-old girl who underwent foramen magnum decompression without dural closure for Chiari I malformation. Three years after the operation an intradiploic pseudomeningocele was documented, but the patient was lost to follow-up without undergoing revision surgery. Four years later, at the age of 11 years, the patient returned for treatment of intensifying symptoms. Radiological imaging then showed an increase in the size of the intradiploic pseudomeningocele and a new cervical syrinx. The patient underwent a first revision surgery in which a part of the internal layer of the occipital bone was removed and arachnoid scar lysis was performed. Two months later the syrinx had worsened, and in a second revision surgery a pseudomeningocele-peritoneal shunt was placed. Here, the authors describe what is to their knowledge the first case of an intradiploic pseudomeningocele and de novo syringomyelia formation following Chiari I decompressive surgery.

Decompressive surgery for Chiari I malformation in children without dural repair: a still effective and safe procedure?

PURPOSE: There are numerous publications about the technical aspects of decompressive surgery for Chiari I malformation highlighting many variations of this procedure. Each approach has its followers. Bony decompression of the foramen magnum alone or with the removal of a portion of the posterior arch of C1, dural splitting with keeping arachnoid intact, and durotomy are described. Dural closure is done with various materials. We retrospectively reviewed foramen magnum decompression without dural repair (FMDWDR) following the technique used by Gardener and Williams as an option in pediatric patients with Chiari I malformation in terms of complication rate and clinical outcome. METHODS: The surgical database of our unit identified 65 consecutive children who underwent FMDWDR surgery for Chiari I malformation between 2009 and 2016. The retrospective assessment included patient demographics, clinical data, surgical technique, revision rate, complications, and clinical outcome. RESULTS: Durotomy without repair was performed in 65 patients. Complications included aseptic meningitis and subdural hematoma respectively in three cases, intradiploic CSF collections in three patients, and CSF leaks in six children. The CSF leak rate has reduced dramatically after introducing a technical modification. Revision surgery was performed in seven cases. None of the patients was identified with postoperative hydrocephalus or infection. There was no mortality and no long-term surgical morbidity. In terms of clinical outcome, 52 patients reported postoperative improvement, 10 were clinically unchanged, and three noticed worsening of symptoms. CONCLUSION: Applying a "T"-shaped fascial incision which allows a watertight closure of the fascia FMDWDR is still a safe and effective treatment option for Chiari I malformation in children.

Minimal invasive lumbar spine revision surgery at distance from the dura and postsurgical scar tissue: Extraforaminal Lumbar Interbody Fusion (ELIF).

Lumbar spine revision surgery is considered as challenging and related to longer operation time and complications because of the loss of anatomical landmarks and the formation of postoperative epidural fibrosis. Minimal invasive lumbar spinal surgery techniques have been refined over the last 5 years but the reexposure of the dura, the formation of postsurgical scar tissue and related dural tears remain a source of complications. For lumbar spinal revision surgery we advocate the minimal invasive Extraforaminal Lumbar Interbody Fusion (ELIF) technique. It employs a working corridor of 45° relative to the midline. This angle permits bypassing laterally the dural sac and postoperative epidural fibrosis so that dural tears do not occur. ELIF is performed without an expandable tubular retractor system, it is atraumatic following the natural intermuscular cleavage plane between the multifidus muscle and the longissimus thoracis muscle pars lumborum. Postoperatively the muscles do not show signs atrophy or fatty degeneration. In case of discectomy alone there is no need for the removal of the facets, if intracanalar lesions are targeted the partial removal of the superior facet is sufficient. ELIF represents an alternative to posterior lumbar interbody fusion (PLIF), conventional open transforaminal lumbar interbody fusion (TLIF), and minimal invasive (MIS) TLIF for lumbar spinal revision surgery.

Constant dripping wears away the bone: intraosseous C2 and suboccipital intradiploic cerebrospinal fluid collection after Chiari I decompressive surgery.

The objective of decompressive surgery for Chiari I malformation is to create additional space to accommodate the ectopic cerebellar tonsils and to improve the flow of cerebrospinal fluid. To the best of our knowledge, we report the first case of a patient with previous Chiari I decompression presenting 5 years after surgery at the same time as an intraosseous C2 and a suboccipital intradiploic cerebrospinal fluid accumulation. Because of the progressive nature of the C2 cerebrospinal fluid collection causing bone destruction, surgical management was indicated. To avoid the erosion of the bone, we propose that the iatrogenic exposure of the diploe and the vertebral spongiosa that may come into contact with the cerebrospinal fluid should be sealed off with bone wax or a similar material.

Extraforaminal Lumbar Interbody Fusion at the L5-S1 Level: Technical Considerations and Feasibility.

Background Extraforaminal lumbar interbody fusion (ELIF) surgery is a muscle-sparing approach that allows the treatment of various degenerative spinal diseases. It is technical challenging to perform the ELIF approach at the L5-S1 level because the sacral ala obstructs the view of the intervertebral disk space. Methods We reported earlier on the ELIF technique in which the intervertebral disk is targeted at an angle of 45 degrees relative to the midline. In this article we describe the technical process we developed to overcome the anatomic relation between the sacral ala and the intervertebral disk space L5-S1 that hinders the ELIF approach at this level. We then report in a retrospective analysis on the short-term clinical and radiologic outcome of 100 consecutive patients with degenerative L5-S1 pathologies who underwent ELIF surgery. Results The L5-S1 ELIF approach could be realized in all patients. The short-term clinical outcome was evaluated 5 months after surgery: 92% of the patients were satisfied with their postoperative result; 8% had a poor result. Overall, 17% of the patients presented light radicular or low back pain not influencing their daily activity, and 82% of the patients working before surgery returned to work 3 to 7 months after surgery. The radiologic outcome was documented by computed tomography at 5 months after surgery and showed fusion in 99% of the patients. Lumbar magnetic resonance imaging performed in 5 patients at 6 months after surgery revealed the integrity of the paraspinal muscles. Conclusions ELIF surgery at the L5-S1 level is technically feasible for various degenerative spinal diseases. Analysis of the clinical and radiologic data in a consecutive retrospective cohort of patients who underwent this surgical procedure showed a good short-term clinical outcome and fusion rate.

Intradiploic pseudomeningocele and ossified occipitocervical pseudomeningocele after decompressive surgery for Chiari I malformation: report of two cases and literature review.

Intradiploic cerebrospinal fluid (CSF) collections are rare findings. The authors describe two pediatric patients with iatrogenically induced occipital CSF collections after decompressive surgery for Chiari I malformation. The first patient presents a large occipital intradiploic pseudomeningocele and the second patient an intradiploic pseudomeningocele merging with an ossified occipitocervical pseudomeningocele. Though being rarities after decompression for Chiari I malformation, intradiploic fluid collection and ossified pseudomeningocele should be considered if patients represent with aggravating presurgical or new symptoms.

Epidural Fibrosis Seen from a Different Angle: Extraforaminal Lumbar Interbody Fusion.

Background Postoperative epidural fibrosis (PEF) localized around the exposed dura and nerve roots is a known radiologic entity seen after lumbar surgery. Although excessive PEF is associated with residual and new lumbar pain and radiculopathy, its role as the generator of the pain is still discussed. Various materials acting as an adhesion barrier have been tested. There is no undebated class I evidence that any one of them is suitable to reduce or avoid PEF and provide a better clinical outcome. In revision surgery, the dissection of epidural scar tissue is time consuming and related to an elevated risk of dural tear and nerve damage. To avoid the formation of posterior PEF, we propose a surgical approach whose working corridor is situated lateral to the dural sac and the nerve roots: the extraforaminal lumbar interbody fusion (ELIF) technique. Methods Description of ELIF surgical technique. Conclusions The ELIF technique is a muscle-sparing approach to the intervertebral disk space and the spinal canal that avoids the formation of posterior PEF. It represents an option to treat various degenerative lumbar spinal diseases as well as offering another approach for revision surgery in patients who have developed PEF.

Chiari I malformation as part of the Floating-Harbor syndrome?

We report the first case of a patient diagnosed with Floating-Harbor syndrome (FHS) and Chiari I malformation. The 3-year-old girl was of proportional short stature, had delay of language development, conductive hearing loss and a high threshold of pain. Diagnosis of Chiari I malformation may be difficult in FHS patients who present with communication problems. Clinicians following patients with FHS should be aware of a possible relation between FHS and Chiari I malformation.

Does size matter? Decompressive surgery under review.

In patients with traumatic brain injury (TBI) and ischemic hemispheric stroke (IHS), supratentorial decompressive craniectomy (DC) is performed when intracranial pressure (ICP) is unresponsive to medical treatment. There are numerous publications about the indications of supratentorial DC, the selection of patients eligible for surgery, the complications of the procedure, and the neurological outcome of operated patients. Only few papers, however, describe comprehensively the technical aspects of this procedure. DC consists of a variety of steps that can be conducted in different manners. Based on the literature reviewed, this article gathers features that had been developed with the intent to improve the decompressive effect of this surgery and evaluates if there is a strong recommendation for clinical practice. The existing literature does not supply class I evidence of how an ideal DC should be designed to reduce peri- and postoperative complications and to provide the best functional outcome.

Coincidence of cervical spondylotic myelopathy and intramedullary ependymoma: a potential diagnostic pitfall.

The authors report the case of a 58-year-old man presenting with a 3-year history of clinical signs of progressive cervical spondylotic myelopathy (CSM). Magnetic resonance imaging showed a severe stenosis of the cervical spinal canal at C3-4 and C5-6 levels due to multiple discopathies. High signal intensities on T2-weighted MR images of the spinal cord and low signal intensities on T1-weighted images at the C2-6 levels were noted, as was contrast enhancement at the C3-4 level. The patient underwent a bilateral decompressive laminectomy at C3-6. The patient did not show any clinical improvement. Thus, further cervical MR imaging was performed and the differential diagnosis of an intramedullary tumor was considered in view of the persisting intramedullary enhancement. This diagnosis prompted a second operation involving a posterior midline myelotomy and excision of an intramedullary ependymoma at the C3-4 level. Intramedullary tumors should be considered in the differential diagnosis of CSM with an atypical pattern of MR imaging features.

Extreme sensitivity of hearing to decreases of ICP in Menière's disease.

We report the case of a Menière's disease patient affected by normal pressure hydrocephalus (NPH) who presented a cerebrospinal fluid (CSF) pressure-dependent hearing impairment after shunting. This side-effect was not only reversible and reproducible but occurred at a high opening pressure when the valve setting was lowered by only 0.7 mmHg (10 mmH(2)O). This observation suggests that hearing in Menière's disease might be very sensitive to small reductions of intracranial pressure (ICP) and that these patients should be informed of this potential risk, which can compromise the efficacy of the shunt.