Postoperative pneumocephalus and recurrence and outcome of chronic subdural hematoma: a systematic review and meta-analysis

We conducted a meta-analysis to analyze the effects of pneumocephalus after chronic subdural hematoma (CSDH) surgery on hematoma recurrence, mortality, and functional outcomes. In this meta-analysis, following PRISMA guidelines, PubMed, Embase, Cochrane Library, and Web of Science online databases were queried using the keywords "pneumocephalus," "pneumoencephalos," "intracranial pneumatocele," "pneumo encephalon," "subdural air," and "chronic subdural hematoma." The results were limited to English-language articles. Through the online database, we identified a total of 276 articles and finally included 14 articles for meta-analysis. The results showed that the recurrence rate in the pneumocephalus group was higher than that in the control group, with a pooled OR of 3.35 (CI: 2.51-4.46, P < 0.001). There was no difference in recurrence rate between the no/few and moderate pneumocephalus groups (OR: 1.27, CI: 0.68-2.37, P = 0.46), but the recurrence rate of the large pneumocephalus group was significantly higher than that of the moderate group, with a pooled OR of 3.29 (CI: 1.71-6.32, P < 0.001). This study failed to show higher mortality and worse outcomes in the pneumocephalus group than in the control. Pneumocephalus after surgical evacuation of CSDH was associated with the recurrence rate of hematoma. Pneumocephalus affecting recurrence was correlated with gas volume, and moderate pneumocephalus may have less impact, while patients with large pneumocephalus are more likely to recur than those with moderate pneumocephalus. More prospective cohort studies are needed for further investigation and verification. This meta-analysis was registered (PROSPERO CRD42022321800).

Extensive tension pneumocephalus presented in the setting of a challenging etiology

Background

Pneumocephalus (PNC) is a well-described consequence in postoperative settings and skull fractures that is usually self-limiting. It can get complicated into tension PNC on some rare occasions, leading to an intracranial mass effect. PNC was also reported after unintentional dural puncture throughout the epidural anesthesia process. However, tension PNC resulting from epidural anesthesia procedures is an extremely rare outcome that implies urgent intervention to relieve the tension within the brain. Here, we report a case of an extensive tension intraventricular PNC 2 days following an epidural anesthesia procedure for a femur fixation surgery.

Case Description

A 23-year-old male presented to the emergency department with basal skull fractures and a femur fracture due to a motorcycle accident. His skull base fracture was managed conservatively then he underwent a femur fixation procedure under epidural anesthesia. Two days after, he developed a severe headache with a disturbed level of consciousness. Computed tomography of the brain revealed an extensive PNC that involved all the subarachnoid spaces down to the cervical region and compressing the cerebellum, which was not found in the initial imaging. The patient's status improved after the twist-drill burr-hole evacuation of air under the water seal.

Conclusion

Extensive tension PNC can occur after traumatic brain injury, especially after epidural anesthesia. Such cases should gain high focus because they may differ from simple PNC regarding diagnosis, treatment, and follow-up.

Tension Pneumocephalus Associated with Negative Pressure Wound Therapy with Instillation and Dwell Time for Methicillin-resistant Staphylococcus aureus Infection After Spinal Deformity Surgery

PURPOSE

Surgical site infection (SSI) is a serious complication after spine surgery. Recently, it has become possible to perform negative pressure wound therapy with instillation and dwell time (NPWTi-d) for postoperative infected wounds. We report the first rare case of symptomatic pneumoencephalopathy following NPWTi-d for methicillin-resistant Staphylococcus aureus (MRSA) infection after spinal deformity surgery.

METHODS

Retrospective review of a patient's medical record and imaging.

RESULTS

A 77-year-old female patient underwent posterior corrective fixation with no intraoperative complications. On the 10th postoperative day, SSI was diagnosed, and debridement was performed. Since MRSA was detected in the wound culture, and a prolonged inflammatory reaction was observed, NPWTi-d was started to preserve the instrumentation. Gradually, good granulation was observed, and the extensive soft tissue defect decreased. On the 29th day after the start of NPWTi-d, the patient experienced sudden headache and neck pain while standing, and head computed tomography led to the diagnosis of symptomatic pneumoencephalopathy. NPWTi-d was discontinued, and when surgery was performed to close the wound, dural injury was found, which was not present at the time of the initial surgery, and dural repair was performed. After 2 weeks of bed rest, the patient's pneumoencephalopathy improved. Three years have passed since the surgery, and no recurrence of cerebrospinal fluid leakage or infection has been observed.

CONCLUSIONS

Although NPWTi-d is a useful treatment for SSI, it is always necessary to pay attention to the development of pneumoencephalopathy and promptly diagnose and treat it because of the risk of life-threatening complications.

Valve-controlled chronic subdural hematoma drainage: A feasibility study

INTRODUCTION

Pneumocephalus after chronic subdural hematoma (CSDH) evacuation is a potential predictor of hematoma recurrence.

RESEARCH QUESTION

To study the feasibility and safety of a novel CSDH evacuation technique using a valve-controlled method to avoid pneumocephalus.

MATERIAL AND METHODS

In a retrospective case series, we evacuated CSDH using very low-pressure valve-controlled drains and recorded the neurological, radiological, and functional outcomes. Patients with primary CSDH, without previous neurosurgical intervention, and who did not receive antiplatelet or anticoagulant therapy the week prior to the index surgery, were included in the study. Exclusion criteria were the evacuation with other treatment techniques and incomplete data files. Patients were assessed according to the Bender grading system to record the neurological status. The hematoma volume was estimated using the formula for ellipsoid volumes.

RESULTS

Thirty-six patients with a mean age of 73 years (±9 years) fulfilled our eligibility criteria. Our technique was effective since it decreased the CSDH volume from 141 ​ml (IQR 97 ​ml) to 20.6 ​ml (IQR 26.59 ​ml; p ​< ​0.001) and improved the neurological status according to the Bender grading system from two (IQR 0.25) to 1 (IQR 0). However, pneumocephalus and hematoma recurrence occurred in one case each (2.8%). At six months, all patients returned to their previous status, except for two patients (5.6%) who died due to irrelevant pathologies.

CONCLUSIONS

Valve-controlled CSDH evacuation aiming to decrease the postoperative pneumocephalus and hematoma recurrence constitutes an effective and safe alternative. However, larger randomized controlled studies are required to establish its role in CSDH management.

Traumatic Subarachnoid-Pleural Fistula with Pneumocephalus

Traumatic subarachnoid-pleural fistula is an uncommon occurrence. We present a case of a patient sustaining a subarachnoid-pleural fistula after a gunshot wound to the neck, which ultimately resulted in substantial pneumocephalus. The patient underwent successful operative repair of the fistula with notable improvement and resolution of pneumocephalus.

Air travel with pneumocephalus: a systematic review

INTRODUCTION

Concerns arise when patients with pneumocephalus engage in air travel. How hypobaric cabin pressure affects intracranial air is largely unclear. A widespread concern is that the intracranial volume could relevantly expand during flight and lead to elevated intracranial pressure. The aim of this systematic review was to identify and summarise models and case reports with confirmed pre-flight pneumocephalus.

METHODS

The terms (pneumocephalus OR intracranial air) AND (flying OR fly OR travel OR air transport OR aircraft) were used to search the database PubMed on 30 November 2021. This search returned 144 results. To be included, a paper needed to fulfil each of the following criteria: (i) peer-reviewed publication of case reports, surveys, simulations or laboratory experiments that focussed on air travel with pre-existing pneumocephalus; (ii) available in full text.

RESULTS

Thirteen studies met the inclusion criteria after title or abstract screening. We additionally identified five more articles when reviewing the references. A notion that repeatedly surfaced is that any air contained within the neurocranium increases in volume at higher altitude, much like any extracranial gas, potentially resulting in tension pneumocephalus or increased intracranial pressure.

DISCUSSION

Relatively conservative thresholds for patients flying with pneumocephalus are suggested based on models where the intracranial air equilibrates with cabin pressure, although intracranial air in a confined space would be surrounded by the intracranial pressure. There is a discrepancy between the models and case presentations in that we found no reports of permanent or transient decompensation secondary to a pre-existing pneumocephalus during air travel. Nevertheless, the quality of examination varies and clinicians might tend to refrain from reporting adverse events. We identified a persistent extracranial to intracranial fistulous process in multiple cases with newly diagnosed pneumocephalus after flight. Finally, we summarised management principles to avoid complications from pneumocephalus during air travel and argue that a patient-specific understanding of the pathophysiology and time course of the pneumocephalus are potentially more important than its volume.

Tension pneumocephalus: case report and review

Tension pneumocephalus is a rare complication of frontal sinus fracture or neurosurgical intervention resulting from compression of the brain by entrapped air, leading to seizure, altered mental status, brain herniation, and death. This report presents a case of traumatic tension pneumocephalus associated with an anterior and posterior table frontal sinus fracture in a patient with pneumosinus dilatans and osteogenesis imperfecta.

Pneumocephalus and headache following craniotomy during the immediate postoperative period

Background

Pneumocephalus may be responsible for post-craniotomy headache but is easily overlooked in the clinical situation. In the present study, the relationship between the amount of intracranial air and post-craniotomy headache was investigated.

Methods

A retrospective observational study was performed on 79 patients who underwent minimal invasive craniotomy for unruptured cerebral aneurysms. Those who had undergone previous neurosurgery, neurological deficit before and after surgery were excluded The amount of air in the cranial cavity was measured using brain computed tomography (CT) taken within 6 h after surgery. To measure the degree of pain due to intracranial air, daily and total analgesic administration amount were used as a pain index. Correlation between intracranial air volume and total consumption of analgesic during hospitalization was tested using Spearman rank correlation coefficients. Receiver operating characteristics (ROC) analysis was used to determine the amount of air associated with increased analgesic consumption over 72 h postoperatively.

Results

The mean amount of intracranial air was 15.6 ± 9.1 mL. Total administration of parenteral and oral analgesics frequency were 6.5 ± 4.5, 13.2 ± 7.9 respectively. A statically significant correlation was observed between daily and total parenteral analgesic consumption after surgery and the amount of intracranial air at followed-up brain CT postoperatively within 24 h (r = 0.69, p < 0.001), within 48 h (r = 0.68, p < 0.001), and total duration after surgery (r = 0.84, p < 0.001). The optimal cut-off value of 12.14 mL of intracranial air predicts the use of parenteral analgesics over 72 h after surgery.

Conclusions

Pneumocephalus may be a causative factor for post-craniotomy pain and headache with surgical injuries.

Pneumocephalus after posterior fossa surgery in prone position: Is that any clinical effect?

Introduction

The term pneumocephalus refers to the existence of air in any intracranial compartment. Its presence in the follows of a supratentorial craniotomy is very common, and it usually represents a benign complication as it is very rarely responsible for clinical manifestations.

Case presentation

We report the case of a 24 years-old man, who underwent posterior fossa surgery in prone position for resection of a vermian tumor. Postoperative, the patient presented a tonic-clonic generalized seizure associated to high levels of arterial pressure and decerebration. Control CT scan showed an important pneumocephalus. On the posterior fossa, the air was responsible for a compression of the brainstem, without any other postoperative complications. Following 12 h of conservative management, a brain MRI showed a total regression of the pneumocephalus. 3 days later, the patient presented a favorable outcome as he was extubated without any major impairments.

Discussion

Transformation of pneumocephalus into tension pneumocephalus responsible for clinical inadvertance is rare. This complication is mainly related to surgeries performed in sitting position. The occurrence of compressive pneumocephalus after a posterior fossa craniotomy performed in a prone position is seldom.

Conclusions

Through this case, we discuss pathophysiology and therapeutic approaches for tension pneumocephalus following posterior fossa performed in prone position.

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Pneumocephalus may be source for major postoperative inadvertance

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Tension pneumocephalus was reported in supratentorial surgeries. Posterior fossa craniotomies may also lead to this inadvertence.

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Rigorous peroperative prevention of pneumocephalus should be considered in order to minimize complications.

The pressure differential efflux technique - A novel approach for troubleshooting air-locked external ventricular drainage systems: A technical note and review of literature

External ventricular drainage (EVD) is carried out in many neurosurgical conditions for the diversion of cerebrospinal fluid. These EVD systems can, however, malfunction with potentially lethal consequences. Air bubbles within the EVD can result in air locking of the system with subsequent blockage of drainage, with blood clots and debris being the other causes. There are both non-invasive and invasive methods of rectifying such blockages, with invasive procedures having its associated risks. This is especially so for EVD revisions, with each surgery increasing the risk of ventriculitis. We describe a case of bilateral air locked EVD managed successfully with a novel non-invasive 'pressure differential efflux technique'. This method exploits the pressure gradient established by adjusting each EVD to a different height to evacuate the pneumoventricle. In addition, we present a sequential approach to the management of EVD malfunction, based on the current literature and our institutional protocol.

Iatrogenic pneumocephalus following a cervical epidural steroid injection: A case report

Pneumocephalus is a condition defined by air present in the intracranial space. There are several causes of pneumocephalus, however this is a case of a patient who developed pneumocephalus following a cervical epidural steroid injection. Uniquely, this patient's chief complaint was sudden onset of syncope, and respiratory arrest following the injection. The diagnosis was made by CT, and conservative treatment was used for resolution of the condition. Patients with pneumocephalus can present with a wide range of neurologic symptoms, and prompt recognition and treatment are key to preventing irreversible neurologic damage.

Clinical Outcomes and Prognostic Determinants of Surgically Treated Depressed Skull Fracture in Addis Ababa University Neurosurgical Teaching Hospitals: A Prospective Multicenter Observational Study

BACKGROUND

Depressed skull fracture is one of the most common neurosurgical emergencies in Ethiopia. The clinical outcome after surgical management and what factors predict the outcome are not well studied. Our study aimed to assess the outcome and identify predictors of the outcome in surgically treated adult patients.

METHODS

A prospective, multicenter, observational study was undertaken on 197 cases, at 4 selected neurosurgical teaching hospitals in Ethiopia. Relevant data were collected and analyzed using Statistical Package for the Social Sciences software (IBM, Armonk, New York, USA). The outcome was assessed by the extended Glasgow Outcome Scale. Multivariate analysis was done to identify independent predictors of the outcome.

RESULTS

The outcome was favorable in 81.2%. The mean age was 27. The mode of injury was violence in 79.7%. Motor deficit witnessed in 24.4%. Based on the Glasgow Coma Scale, 92.2% of patients had mild traumatic brain injury. Associated intracranial lesions were identified in 87.3%. The median hospital stay was 4.7 days. Reoperation and mortality rates were 4.1% and 0.5%, respectively. Five factors were statistically significant independent predictors of unfavorable outcome in multivariate analysis: motor deficit (adjusted odds ratio [AOR] 13.8, 95% confidence interval [CI]: 4.13-46.17, P = 0.000), Glasgow Coma Scale ≤13 (AOR 10.36, 95% CI: 1.93-55.56, P = 0.006), pneumocephalus (AOR 12.93, 95% CI: 3.12-53.52, P = 0.000), hospital stay for ≥3 days (AOR 4.39, 95% CI: 1.18-16.3, P = 0.027), and reoperation (AOR 6.92, 95% CI: 1.09-43.97, P = 0.04).

CONCLUSIONS

The overall outcome was favorable. The presence of motor deficit, postresuscitation Glasgow Coma Scale ≤13, pneumocephalus, reoperation, and hospital stays for ≥3 days were independent predictors of an unfavorable outcome.

Delayed brain reexpansion in schizophrenic patient affected by trabecular type chronic subdural hematoma

Background:

Chronic subdural hematoma (cSDH) represents a complex and unpredictable disease, characterized by high morbidity and mortality, especially in elderly patients. Factors affecting the postoperative brain reexpansion along to cSDH recurrence have not been yet adequately investigated. The authors presented the case of a schizophrenic patient affected by trabecular type cSDH that presented a delayed brain reexpansion despite a craniotomy and membranotomy.

Case Description:

A 51-year-old female patient with diagnosis of schizophrenia was admitted to the emergency department with GCS score of 5/15 and right anisocoria. An urgent brain CT revealed a trabecular right cSDH (35 mm in maximum diameter) with recent bleeding. After surgery, a brain CT scan showed a markedly reduced brain reexpansion and pneumocephalus. Nevertheless, postoperative 7-day brain CT documented a progressive brain reexpansion with reduced midline shift.

Conclusion:

According to our opinion, anatomopathological alterations in schizophrenia reduce normal brain compliance and increasing elastance, thus modifying the normal timing of reexpansion after cSDH drainage, also after craniotomy and membranotomy. Although postoperative pneumocephalus is a well-known cause of hindered reexpansion, this could be due to anatomical alterations in schizophrenia. Such factors must be considered in the preoperative planning but mostly in the postoperative management.

Leptomeningeal pneumocephalus and pneumorrhachis: Signs of pneumothorax in case of syringopleural shunting

In this article, we present a case of leptomeningeal pneumocephalus and pneumorrhachis secondary to pneumothorax that occurred six years after syringopleural shunting.

Pneumocephalus secondary to a spinal surgery: A literature review and a case report

Introduction

We report a case of pneumocephalus, which is identified as the presence of air in the cranial cavity and is a rare complication after spinal surgeries, in addition to a literature review of similarly reported cases.

Case presentation

The patient is a 63-year-old male who developed pneumocephalus after undergoing a minimally invasive left side decompression at L3-L4 with left L4 foraminotomy even though there were no signs of dural tears or Cerebrospinal Fluid (CSF) leaks. After the diagnosis of pneumocephalus using brain Magnetic Resonance Imaging (MRI), the patient was treated conservatively and was discharged after 3 weeks without developing further complications.

Discussion

Pneumocephalus is defined as an abnormal accumulation of air within the cranial cavity. It can occur due to a variety of causes but rarely due to gas forming bacteria. Many theories are suggested concerning the pathophysiology of pneumocephalus, the inverted bottle theory, the ball valve theory, the Nitrous Oxide (N₂O) theory, and as we outweigh in our case, gas forming bacteria theory. Pneumocephalus can be treated surgically, nevertheless, conservative management methods of such cases are usually followed.

Conclusion

The aim of this study is to draw further attention to the management and diagnosis of such surgical complication. A more extended research is needed to provide a full comprehensive approach to deal with this problem if faced in the future. To the best of our knowledge, this study reports the first pneumocephalus case induced by a postoperative bacterial infection in the global English based medical literature.

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Pneumocephalus caused by gas forming infection in the spine is a rare complication after spinal surgery.

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Unexplained headache spinal surgeries should raise suspicion toward pneumocephalus.

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There are many theories regarding the development of pneumocephalus, each one need specific attention.

Expanding pneumocephalus due to craniofacial fractures: A case report

Introduction

Pneumocephalus (PNC) is the presence of air in the intracranial cavity. The most frequent cause is craniofacial trauma, though there are many etiologies, including surgical procedures. PNC with compression of the frontal lobes and widening of the interhemispheric space between the tips of the frontal lobes results in the characteristic radiological finding of the “Mount Fuji sign”.

Presentation of case

A 57-year-old man presented to the A&E with loss of consciousness due to a motorcycle collision 9 h prior. He had a GCS of E4M6V5, and a head CT scan revealed minimal PNC forming in both hemispheres. After discharge, severe headaches and rhinorrhea developed. A second CT scan revealed a massive PNC. An operation was then performed via a bicoronal incision to drain the PNC and seal the cranial defect. A burr hole in the calvarium was created, and the cranial defect was closed using a pericranial rotational flap. Post-operation, the patient's headache and rhinorrhea decreased; neither symptom was present at 1-month post-operation. The wounds healed with minimal scarring, and the cosmetic outcome for the craniofacial fracture was acceptable.

Discussion

Although the patient may at first present with a mild head injury, this can progress into something much more serious. PNC is difficult to diagnose clinically. Rarely, patients describe a splashing sound upon moving the head (termed bruit hydro-aerique), which can also be auscultated. A head CT scan is the gold standard in the diagnosis of PNC. Pericranial flaps are widely used for dural repair because they are easily accessible and have a lower rate of infection than artificial grafts on expanding PNC.

Conclusion

Tension PNC may be slow-growing and increase intracranial pressure to high levels before clinical signs are present. The pericranial rotational flap technique is the best way to close a dura mater defect in cranial base fractures with tension PNC.

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Pneumocephalus (PNC) is the presence of air in the intracranial cavity.

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Craniofacial trauma is the most frequent cause of PNC.

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We report a male with expanding PNC who required a pericranial rotational flap.

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Tension PNC may be slow-growing and increase intracranial pressure to high levels before clinical signs are present.

Diagnosis, treatment and postsurgical complications in a dog with epileptic seizures and a naso-ethmoidal meningoencephalocele

BACKGROUND

Naso-ethmoidal meningoencephalocele is usually a congenital anomaly consisting of a protrusion of cerebral tissue and meninges into the ethmoidal labyrinth. The condition is a rare cause of structural epilepsy in dogs. We report the clinical presentation, surgical intervention, postoperative complications and outcome in a dog with drug resistant epilepsy secondary to a meningoencephalocele.

CASE PRESENTATION

A 3.3-year-old male neutered Tamaskan Dog was referred for assessment of epileptic seizures secondary to a previously diagnosed left-sided naso-ethmoidal meningoencephalocele. The dog was drug resistant to medical management with phenobarbital, potassium bromide and levetiracetam. Surgical intervention was performed by a transfrontal craniotomy with resection of the meningoencephalocele and closure of the dural defect. Twenty-four hours after surgery the dog demonstrated progressive cervical hyperaesthesia caused by tension pneumocephalus and pneumorrhachis. Replacement of the fascial graft resulted in immediate resolution of the dog's neurological signs. Within 5 months after surgery the dog progressively developed sneezing and haemorrhagic nasal discharge, caused by sinonasal aspergillosis. Systemic medical management with oral itraconazole (7 mg/kg orally q12h) was well-tolerated and resulted in resolution of the clinical signs. The itraconazole was tapered with no relapsing upper airway signs. The dog's frequency of epileptic seizures was not affected by surgical resection of the meningoencephalocele. No treatment adjustments of the anti-epileptic medication have been necessary during the follow-up period of 15 months.

CONCLUSIONS

Surgical resection of the meningoencephalocele did not affect the seizure frequency of the dog. Further research on prognostic factors associated with surgical treatment of meningoencephaloceles in dogs is necessary. Careful monitoring for postsurgical complications allows prompt initiation of appropriate treatment.

The importance of imaging in diagnosis of infected otogenic pneumatoceles

OBJECTIVE

Spontaneous otogenic pneumatocele is a rare entity resulting from a pressure gradient between a dehiscent temporal bone and the intracranial space. Secondary infection can ensue in patients with concurrent otomastoiditis. The current study discusses the clinical presentation and imaging characteristics of two cases of secondarily infected otogenic pneumatoceles.

STUDY DESIGN

Case series.

RESULTS

Two patients were diagnosed with a temporal lobe abscess in the setting of otogenic pneumatocele. Diagnosis was aided by both CT and MRI demonstrating a diffusion restricting lesion within brain parenchyma in association with free air in close proximity to an underlying tegmen defect.

CONCLUSION

Prompt diagnosis of a secondarily infected otogenic pneumatocele with CT and MRI allows for surgical drainage with closure of the tegmen defect to prevent further complications and recurrence.

Rare incidence of tension pneumocephalus 2 months after repeat microvascular decompression

Background:

Tension pneumocephalus is a rare complication after intracranial procedures and craniotomy. We report a rare case of intraventricular and subdural tension pneumocephalus occurring 2 months after repeat right-sided microvascular decompression (MVD) for recurrent trigeminal neuralgia.

Case Description:

The patient in this case was a 79-year-old woman who presented with acute-onset confusion, headaches, nausea, and vomiting. On computed tomography, substantial volumes of pneumocephalus in the fourth ventricle and subdural space at the site of the retrosigmoid exposure for the previous MVD were seen. She underwent emergent wound exploration, and no obvious dural defect or exposed mastoid air cells were identified. The dura was reopened, and the surgical site was copiously irrigated. Mastoid air cells were covered with ample amounts of bone wax, and the wound was closed. The patient recovered well postoperatively with complete resolution of the pneumocephalus by her 3-month follow-up evaluation.

Conclusion:

It is important to assess for cerebrospinal fluid leakage and that air cells are sealed off before wound closure to prevent a pathway for air to egress into the surgical cavity and corridor.

Pneumocephalus in thoracoabdominal aortic aneurysm repair after lumbar drain removal and blood patch

Lumbar spinal drain use during thoracic and thoracoabdominal aortic aneurysm repair has reduced the incidence of ischemic spinal cord injury with relatively low risk. We report a case of pneumocephalus in a 55-year-old woman who had undergone open repair of a 6.7-cm type IV thoracoabdominal aortic aneurysm. After lumbar spinal drain removal, she developed a postdural headache, which was subsequently treated with blood patch placement. After discharge, she had presented with transient headaches, perioral numbness, and left-hand weakness. Computed tomography revealed intraventricular gas within the lateral ventricles. Pneumocephalus is an exceedingly rare and potentially dangerous complication of lumbar spinal drains and blood patch placement.

Hyperbaric oxygen therapy in the treatment of pneumocephalus associated with epidural block: case report

Introduction

Pneumocephalus is a rare neuraxial blockade complication, which can be associated with severe neurologic changes.

Clinical case

A 51-year-old patient was submitted to left total knee arthroplasty. Postoperatively, a pneumocephalus associated with decreased consciousness was diagnosed as a complication of the epidural analgesia. The treatment used was Hyperbaric Oxygen Therapy (HBOT) due to the severity of symptoms. Just after one session of HBOT, there was nearly full pneumocephalus resorption and significant clinical recovery.

Conclusion

This case report enables anesthesiologists to recognize HBOT as a therapeutic option to be considered when treating severe cases of pneumocephalus.

Unilateral Tension Pneumocephalus of the Sylvian Fissure: A Rare Neurosurgical Complication

Tension pneumocephalus is an uncommon complication of neurosurgical procedures. We report a patient who presented with headache, vomiting, left hemiparesis and rhinorrhea 30 days after correction of a recurrent nasal cerebrospinal fluid fistula and shunt placement. A computed tomography scan revealed a massive collection of air with air-fluid level in the right sylvian fissure and midline shift. A right pterional craniotomy was performed and a small corticectomy resulted in evacuation of air from the sylvian fissure. A dural graft from the previous surgery was recognized to be acting as a ball-valve mechanism, trapping air from the nasal cavity. It was removed and the cranial defect was corrected with a split calvarial bone graft. Follow-up brain computed tomography revealed complete resolution of pneumocephalus. After surgery there was progressive improvement of neurological symptoms over 10 days, and the patient was asymptomatic after 1 month of follow-up.

The trajectory of a low-velocity bullet from the chest to the pituitary gland

The diagnosis and treatment of gunshot injuries requires an understanding of the trajectory of the bullet in each individual case. The majority of gunshot wounds present with easily understandable trajectories resulting in a concise, stream-lined work-up. Occasionally, the initial work-up may reveal a trajectory that is atypical. This can be due to internal bullet deflection, bullet embolism, or bullets that traverse multiple body cavities. Here we present the case of a gentleman who was shot in the left posterior chest, with the bullet ultimately lying-in profile with the patient's pituitary gland. The patient suffered injuries to his left lung, left internal jugular vein, and right optic nerve. On hospital day 1, he required neurosurgical operative intervention for increased somnolence and computed tomography findings which revealed tension pneumocephalus. On hospital day 15, he was discharged home after making a full recovery with the exception of continued blindness in the right eye. Gunshot wounds involving multiple body cavities can increase the complexity of a patient's injury pattern and require increased vigilance and complete history, physical examination, and imaging to ensure optimal outcomes.

A rare case of spontaneous otogenic pneumocephalus with pictorial illustration of temporal evolution

Pneumocephalus is commonly seen on imaging in the setting of craniofacial trauma, skull base tumours, intracranial infection and after neurological intervention. Spontaneous pneumocephalus in the absence of these conditions is exceedingly rare, with only approximately 30 cases reported in the literature to date. Spontaneous otogenic pneumocephalus (SOP) is believed to occur as a result of anomalous communication between the intracranial space and a hyper-pneumatised temporal bone, with either positive extra-to-intracranial pressure or negative intracranial pressure gradient. These anomalous communicating channels may only become clinically apparent when triggered by episodes of acute increase in middle ear pressure during coughing, sneezing, Valsalva manoeuvre or significant change in atmospheric pressure. Patients may exhibit a wide range of neurological symptoms and the aim of treatment is to reduce the risk of complications such as infection and intracranial hypertension. Both conservative and neurosurgical approaches have been described. We report a case of SOP in which the patient was conservatively managed, and spontaneous resolution of pneumocephalus was documented on serial computed tomography (CT) scans. This unique case clearly demonstrates the natural history and temporal evolution of SOP without surgical intervention. This knowledge may potentially obviate the need for surgery, thus reducing morbidity and mortality in patients who are poor surgical candidates.

An unusual case of spontaneous nontraumatic pneumocephalus in the setting of remote craniofacial surgery

BACKGROUND

Pneumocephalus is an uncommon pathology that typically follows head trauma, neurosurgery, or skull base tumors. Rarely, cases of spontaneous pneumocephalus can occur, most often in the setting of barotrauma.

CASE DESCRIPTION

We describe a rare case of spontaneous pneumocephalus in the absence of barotrauma in a 31-year-old male who presented with a headache and a normal neurologic exam. Imaging revealed subarachnoid and subdural pneumocephalus. The patient underwent surgical exploration, revealing an ethmoid bone defect caused by encroachment of material from a remote reconstructive surgery of the left orbit, which was subsequently repaired.

CONCLUSION

Although rare, spontaneous pneumocephalus should be considered even in the absence of clinical neurologic findings or barotrauma, in patients with previous cranial surgery and unexplained headaches.