Pneumocephalus: case illustrations and review

Fatal postoperative tension pneumocephalus after acute subdural hematoma evacuation: a case report

PURPOSE

Tension pneumocephalus (TP) represents a rare pathology characterized by constant accumulation of air in the intracranial space, being associated with increased risk of herniation, neurologic deterioration and death. Regarding neurosurgical trauma cases, TP is majorly encountered after chronic subdural hematoma evacuation. In this case report, we present a rare case of fatal postoperative TP encountered after craniotomy for evacuation of acute subdural hematoma (aSDH).

CASE PRESENTATION

An 83-year old gentleman was presented to the emergency department of our hospital with impaired level of consciousness. Initial examination revealed Glascow Coma Scale (GCS) 3/15, with pupils of 3 mm bilaterally and impaired pupillary light reflex. CT scan demonstrated a large left aSDH, with significant pressure phenomena and midline shift. Patient was subjected to an uneventful evacuation of hematoma via craniotomy and a closed subgaleal drain to gravity was placed. The following day and immediately after his transfer to the CT scanner, he presented with rapid neurologic deterioration with acute onset anisocoria and finally mydriasis with fixed and dilated pupils. Postoperative CT scan showed massive TP, and the patient was transferred to the operating room for urgent left decompressive craniectomy, with no intraoperative signs of entrapped air intracranially. Finally, he remained in severe clinical status, passing away on the eighth postoperative day.

CONCLUSION

TP represents a rare but severe neurosurgical emergency that may be also encountered after craniotomy in the acute trauma setting. Involved practitioners should be aware of this potentially fatal complication, so that early detection and proper management are conducted.

Backup Frontal Drainage System for Urgent Tension Pneumocephalus Management After Chronic Subdural Hematoma Surgery: A Retrospective Cohort Study

OBJECTIVE

To describe a simple variation of burr hole craniostomy for the management of chronic subdural hematoma (CSDH) that uses a frontal drainage system to facilitate timely decompression in the event of tension pneumocephalus and spares the need for additional surgery.

METHODS

We conducted a retrospective analysis of 20 patients with CSDH who underwent burr hole craniostomy and 20 patients who underwent the same procedure alongside the placement of a 5 Fr neonatal feeding tube as a backup drainage for the anterior craniostomy. Depending on the situation, the secondary drain stayed for a maximum of 72 hours to be opened and used in emergency settings for drainage, aspiration, or as a 1-way valve with a water seal.

RESULTS

The outcomes of 20 patients who underwent this procedure and 20 controls are described. One patient from each group presented tension pneumocephalus. One was promptly resolved by opening the backup drain under a water seal to evacuate pneumocephalus and the other patient had to undergo a reopening of the craniostomy.

CONCLUSIONS

The described variation of burr hole craniostomy represents a low-cost and easy-to-implement technique that can be used for emergency decompression of tension pneumocephalus. It also has the potential to reduce reoperation rates and CSDH recurrence. Prospective controlled research is needed to validate this approach further.

Extensive Pneumocephalus Secondary to Petrous Bone Cholesteatoma

Pneumocephalus refers to air inside the cranium; however, otogenic pneumocephalus is rarely reported in the literature. The neurological presentations of pneumocephalus include headache, lethargy, confusion, disorientation, and seizure. Here, we have reported a case of a 42-year-old woman with extensive pneumocephalus and cerebrospinal fluid leak secondary to petrous bone cholesteatoma. She presented to the emergency department with sudden headache and left ear discharge. Physical examination revealed watery otorrhea through a hole in the tympanic membrane. Radiological studies demonstrated extensive soft tissue in the left middle ear and mastoid extending to the internal auditory canal. Free intracranial air was observed, and bony destruction was seen in the cochlea, vestibule, and semicircular canals. The patient was managed surgically via the transotic approach and fully recovered. Although otogenic pneumocephalus is rarely encountered in clinical practice, early diagnosis and urgent management are important to prevent fatal complications.

Minimizing pneumocephalus during deep brain stimulation surgery

BACKGROUND

Deep brain stimulation (DBS) surgery is an effective treatment for movement disorders. Introduction of intracranial air following dura opening in DBS surgery can result in targeting inaccuracy and suboptimal outcomes. We develop and evaluate a simple method to minimize pneumocephalus during DBS surgery.

METHODS

A retrospective analysis of prospectively collected data was performed on patients undergoing DBS surgery at our institution from 2014 to 2022. A total of 172 leads placed in 89 patients undergoing awake or asleep DBS surgery were analyzed. Pneumocephalus volume was compared between leads placed with PMT and leads placed with standard dural opening. (112 PMT vs. 60 OPEN). Immediate post-operative high-resolution CT scans were obtained for all leads placed, from which pneumocephalus volume was determined through a semi-automated protocol with ITK-SNAP software. Awake surgery was conducted with the head positioned at 15-30°, asleep surgery was conducted at 0°.

RESULTS

PMT reduced pneumocephalus from 11.2 cm3±9.2 to 0.8 cm3±1.8 (P<0.0001) in the first hemisphere and from 7.6 cm3 ± 8.4 to 0.43 cm3 ± 0.9 (P<0.0001) in the second hemisphere. No differences in adverse events were noted between PMT and control cases. Lower rates of post-operative headache were observed in PMT group.

CONCLUSION

We present and validate a simple yet efficacious technique to reduce pneumocephalus during DBS surgery.

Pneumocephalus and empyema in the subarachnoid space: An unusual imaging feature secondary to spinal-epidural anesthesia

Pneumocephalus and empyema in the subarachnoid space secondary to spinal-epidural anesthesia are very rare and have not previously been reported, to our knowledge. Here, we describe the imaging features of an older woman presenting with pneumocephalus plus subarachnoid and intraventricular empyema due to Staphylococcus epidermidis infection after spinal-epidural anesthesia, with the aim of raising awareness regarding this serious complication.

Spinal procedures, pneumocephalus, and cranial nerve palsies: A review of the literature

Purpose: Minimally invasive and surgical spine procedures are commonplace with various risks and complications. Cranial nerve palsies, however, are infrequently encountered, particularly after procedures such as lumbar punctures, epidural anesthesia, or intrathecal injections, and are understandably worrisome for clinicians and patients as they may be interpreted as secondary to a sinister etiology. However, a less commonly considered source is a pneumocephalus which may, in rare cases, abut cranial nerves and cause a palsy as a benign and often self-resolving complication. Here, we present the case of a patient who underwent an intrathecal methotrexate infusion for newly diagnosed non-Hodgkin's T-cell lymphoma and subsequently developed an abducens nerve palsy due to pneumocephalus. We highlight the utility of various imaging modalities, treatment options, and review current literature on spinal procedures resulting in cranial nerve palsies attributable to pneumocephalus presenting as malignant etiologies.

Sudden-onset, non-traumatic large volume pneumocephalus following presentation of acute bacterial meningitis

A man in his 30s, with sinonasal undifferentiated carcinoma status post resection 6 years prior, presented with acute onset of fever, headache and altered mentation. The patient was diagnosed with bacteremia and meningitis due to Streptococcus pneumoniae A standard antibiotic and corticosteroid regimen was started. Brain MRI showed an encephalocele abutting the superolateral nasopharynx mucosa. After several days of clinical improvement, the patient's mental status and headache acutely relapsed. A CT head venogram showed a large volume pneumocephalus originating from the region of a surgical defect. Management included external ventricular drain placement followed by right pterional craniotomy with skull base packing. Skull base defects increase the risk of life-threatening conditions such as bacterial meningitis and pneumocephalus. It is crucial for clinicians to be aware of the possibility of cranial surgical defects developing years after surgery.

Use of oxygen therapy for pneumocephalus: a systematic review

Pneumocephalus is the pathologic collection of air in the intracranial cavity. In sufficient volumes, it can contribute to symptoms ranging from headaches to death. For conservative treatment, oxygen use is commonplace. Although this is an accepted tenet of clinical practice, it is not necessarily founded on robust trials. An electronic search of databases EMBASE and MEDLINE and the Cochrane Library was undertaken as per the 2020 Preferred Reporting Items of Systematic Reviews and Meta-Analyses (PRISMA) statement. Three articles were included. Although the modes of oxygen delivery were heterogenous (non-rebreather versus endotracheal versus hyperbaric chamber), all studies concluded favorably on the use of oxygen therapy for increased reabsorption of pneumocephalus.

Pneumocephalus resulting from traumatic pneumothorax and brachial plexus avulsion

Background

Traumatic pneumocephalus is commonly encountered after basal skull fractures and rarely associated with blunt chest trauma. Here, we report a case of pneumocephalus caused by traumatic pneumothorax and brachial plexus avulsion.

Case Presentation

A 20-year-old male was admitted to our hospital following a motorcycle accident with complete paralysis of the right upper limb. 2 days later, follow-up computed tomography revealed a slight right pneumothorax, pneumomediastinum around the neck, and intracranial air without skull fracture. Air migrates into the subarachnoid space through a dural tear caused by a brachial plexus avulsion. The pneumocephalus immediately improved after the insertion of a chest drain.

Conclusion

Pneumothorax combined with brachial plexus avulsion could lead to pneumocephalus. Immediate chest drainage might be the best way to stop the migration of air; however, care should be taken to not worsen cerebrospinal fluid leakage.

Early Mobilization and Rehabilitation to Enhance the Functional Performance of a Hemiparesis Patient Following a Subdural and Subarachnoid Hematoma With Pneumocephalus: A Case Report

A subdural hematoma (SDH) is a medical condition caused by a violent head trauma in which blood accumulates excessively under the dura mater. It occurs when a blood arterial weak point or brain surface aneurysm ruptures and bleeds. The resulting blood accumulation inside and around the skull raises the pressure on the brain. Pneumocephalus, also known as pneumatocele or intracranial aerogel, refers to air in the ventricular cavities or brain parenchyma's epidural, subdural, or subarachnoid spaces. In most cases, neurotrauma is the primary cause of pneumocephalus, mainly when there are skull base fractures. Here, we present a case study of a 65-year-old male patient diagnosed with left hemiplegia following SDH with subarachnoid hematoma (SAH) and pneumocephalus. The severity of the patient's illness, the medical and surgical care provided, the amount of physiotherapy required to aid recovery, the duration of hospitalization, and the discharge location for patients with acute SAH or SDH vary significantly. The patient underwent physiotherapy rehabilitation, and we report that his lower limb strength improved substantially after the therapy. Therefore, physiotherapy is a critical component of treatment to enhance muscle strength, facilitate early and rapid recovery, and manage the clinical manifestations of the condition.

Laparoscopic cholecystectomy induce tension pneumocephalus in a patient with ventriculoperitoneal shunt: A case report and literature review

INTRODUCTION AND PATIENT CONCERNS

We report on a 45-year-old woman who has a ventriculoperitoneal shunt (VPS), experienced drowsy mental status, with hypesthesia and hemiplegia on the left side. Ten days ago she underwent laparoscopic cholecystectomy (LC). Computed tomography revealed tension pneumocephalus, with severe compression on the right side of the brain.

INTERVENTIONS AND DIAGNOSIS

She underwent 2 surgeries, the first surgery was to place a subdural drainage catheter, however, the pneumocephalus relapsed after withdrawing the catheter, and the later surgery was to replace the new VPS.

OUTCOMES

After replacing the VPS, the patient recovers completely after 10 weeks of follow-up.

CONCLUSION

To our knowledge, this is the first report of LC-induced tension pneumocephalus in a patient with VPS. The purpose of this study is to share our experience, with the hypothesized mechanism being the retrograde air through the VPS valve because of high abdominal pressurization. We recommend noting the existence of the VPS when the LC or any abdominal laparoscopy is performed. The VPS should be clamped during any laparoscopic procedure until complete depressurization. Furthermore, all patients with VPS who have neurological deterioration after abdominal laparoscopy should be treated as having the diagnosis of a tension pneumocephalus. These patients need emergency surgery to replace VPS and set the valve for high-pressure, which can result in a quick and complete recovery.

Post-dural puncture headache combined with pneumocephalus secondary to vaginal delivery following epidural anesthesia: a case report

BACKGROUND

Pneumocephalus is rare in vaginal deliveries. Pneumocephalus may be asymptomatic or present with signs of increased intracranial pressure. However, parturients who received epidural anesthesia with air in their brains may experience low intracranial pressure headaches after giving birth, causing the diagnosis of pneumocephalus to be delayed. We report a case of a parturient who developed post-dural puncture headache combined with pneumocephalus secondary to vaginal delivery following epidural anesthesia.

CASE PRESENTATION

A 24-year-old G1P0 Chinese woman at 38 weeks gestation was in labor and received epidural anesthesia using the loss of resistance to air technique and had a negative prior medical history. She presented with postural headache, neck stiffness and auditory changes 2 h after vaginal delivery. The head non-contrast computed tomography revealed distributed gas density shadows in the brain, indicating pneumocephalus. Her headache was relieved by bed rest, rehydration, analgesia, and oxygen therapy and completely disappeared after 2 weeks of postpartum bed rest.

CONCLUSIONS

This is the first report that positional headaches after epidural anesthesia may not indicate low intracranial pressure alone; it may combine with pneumocephalus, particularly when using the loss of resistance to air technique. At this moment, head computed tomography is essential to discover other conditions like pneumocephalus.

Unusual Presentation of Pneumocephalus With Late Onset During Labour Epidural Analgesia

A 36-year-old woman with no significant medical history was in active labour and requested labour analgesia. While the epidural technique was performed at the L4-L5 interspace, using the loss of resistance to air technique (LORA), inadvertent dural puncture occurred. Since the patient reported no headache or discomfort, the same procedure was repeated at the L3-L4 interspace successfully. Loss of resistance was reported at 3 cm and the epidural catheter was advanced uneventfully at 8 cm. Aspiration was negative for blood or cerebrospinal fluid (CSF) and a test dose of 2 ml lidocaine 2% was administered epidurally. Within five minutes the patient exhibited a mild hypotensive episode successfully treated with 2.5 mg ephedrine IV, a sensory blockade up to T6 level, and a motor blockade up to T10 level. Both the woman's and the baby's vital signs remained stable, no further drugs were administered epidurally and labour progressed painlessly and uncomplicated for 90 minutes with subsequent vaginal delivery of a healthy newborn. During the episiotomy incision repair, the patient complained of light dizziness and nausea. Her vital signs and the arterial blood gases (ABGs) ordered were within normal range, but the neurological examination revealed an isolated Babinski on the right foot. The head CT scan requested indicated a considerable quantity of air within the subarachnoid region. The patient was treated conservatively; symptoms showed steady improvement with total resolution on the sixth day, and the woman was discharged. This case reemphasizes the possibility of pneumocephalus, which may, in reality, occur more frequently than is commonly recognized without a CT confirmation.

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).

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.

ABC/2 formula for “bedside” postoperative pneumocephalus volume measurement

Background

Postoperative pneumocephalus is associated with a higher risk of recurrence of chronic subdural hematoma (cSDH). However, there is no verified simple way to measure the pneumocephalus volume at the bedside for daily clinical use. The ABC/2 method was shown to be a simple and reliable technique to estimate volumes of intracranial lesions, such as intracranial hematomas. This study aims to evaluate the accuracy of the ABC/2 formula in estimating volumes of pneumocephalus, as compared to the gold standard with computer-assisted volumetric analysis.

Methods

A total of 141 postoperative computed tomographic (CT) brain scans of cSDH patients with burr-hole drainage were analysed. Pneumocephalus volume was measured independently by both the ABC/2 formula and the computer-assisted volumetric measurement. For the computer-assisted measurement, the volume of the air was semiautomatically segmented and calculated by computer software. Linear regression was used to determine the correlation between the ABC/2 method and computer-assisted measurement.

Results

The postoperative pneumocephalus volume after bilateral burr-hole drainage was significantly larger than that of unilateral burr-hole drainage (29.34 ml versus 12.21 ml, p < 0.001). The estimated volumes by the formula ABC/2 significantly correlated to the volumes as measured by the computer-assisted volumetric technique, with r = 0.992 (p < 0.001). The Pearson correlation coefficient is very close to 1, which signifies a very strong positive correlation, and it is statistically significant.

Conclusions

An excellent correlation is observed between the ABC/2 method and the computer-assisted measurement. This study verified that the ABC/2 method is an accurate and simple “bedside” technique to estimate pneumocephalus volume.

• The ABC/2 method is an accurate and simple “bedside” technique to estimate pneumocephalus volume.

• The postoperative pneumocephalus volume after bilateral burr-hole drainage was significantly larger than that of unilateral burr-hole drainage (29.34 ml versus 12.21 ml, p < 0.001).

• The estimated volumes of pneumocephalus by the formula ABC/2 were significantly correlated to the volumes as measured by the computer-assisted volumetric technique, with r = 0.992 (p < 0.001).

Tension Pneumocephalus Following LP Shunt due to Congenital Bone Defects: A Case Report

A 72-year-old man who had undergone a lumboperitoneal shunt for idiopathic normal pressure hydrocephalus was admitted to our emergency department with fever and disturbance of consciousness 8 days after placement. Computed tomography scan showed pneumocephalus and a right-sided temporal porencephalic cyst with a small bone defect in the right petrous bone. Shunt valve pressure was raised from 145 mmH₂O to "virtual off" setting. After 2 weeks, follow-up computed tomography showed improvement of pneumocephalus, and the shunt valve pressure was lowered to 215 mmH₂O. Since that time, the patient has a good clinical course without recurrence. Tension pneumocephalus following shunt placement for idiopathic normal pressure hydrocephalus is rare and has never been reported in the early postoperative stage after lumboperitoneal shunt, except for the present one. Temporary raising shunt valve pressure is effective in improving the pneumocephalus. Preoperative screening for congenital bone defects by thin-slice computed tomography may be useful for selecting types of shunt valve and determining postoperative pressure setting.

Endoscopic Endonasal Eustachian Tube Obliteration as a Treatment for Tension Pneumocephalus After Translabyrinthine Resection of Vestibular Schwannoma

OBJECTIVE

Cerebrospinal fluid leak and pneumocephalus are rare but potentially devastating complications associated with translabyrinthine resection of cerebellopontine angle masses. Persistent pneumocephalus despite proximal eustachian tube (ET) obliteration is rare. We describe, to our knowledge, the first report of successful management of tension pneumocephalus by endoscopic endonasal ET obliteration using a novel V-loc (Covidien; Medtronic, Minneapolis, MN) suture technique.

PATIENTS

A 63-year-old man presented with altered mental status 10 months after translabyrinthine excision of a left cerebellopontine angle vestibular schwannoma measuring 2.8 × 2.9 × 3.3 cm. Computed tomography demonstrated diffuse ventriculomegaly and new pneumocephalus along the right frontal lobe, lateral ventricles, and third ventricle, and air within the left translabyrinthine resection cavity.

INTERVENTION

The patient underwent left-sided endoscopic endonasal ET obliteration using 2-0, 9-inch V-loc suture.

MAIN OUTCOME MEASURE

Postoperatively, the patient's mental status improved with a decrease in size of the lateral and third ventricles on computed tomography.

CONCLUSION

Endoscopic endonasal ET obliteration, a technique previously applied to recalcitrant cerebrospinal fluid leaks, is a safe and reasonable alternative to reentering the original surgical site for patients with pneumocephalus after lateral skull base surgery. Utilizing a V-loc suture for this technique instead of a traditional suture may improve procedural ease and speed.

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.

Application of the subdural evacuating port system for the drainage of postoperative tension pneumocephalus: A technical note

Background:

Tension pneumocephalus is a neurosurgical emergency requiring prompt intervention. A variety of either temporizing or definitive methods was previously described as part of its management. Here, we report on an off-label use of a bed-side device and the subdural evacuating port system (SEPS)™ for the treatment of tension pneumocephalus.

Methods:

The SEPS™ (Medtronic Dublin, Ireland) is a minimally invasive tool that is indicated for the removal of chronic or subacute subdural hematomas and at the patient’s bedside. We describe the use of this system to evacuate tension pneumocephalus.

Results:

A 44-year-old patient operated in our institution was presented with sudden obtundation 4 days post resection of esthesioneuroblastoma. Imaging confirmed a significant tension pneumocephalus. Immediate bedside decompression using a SEPS bolt placed frontally was performed, achieving rapid evacuation and patient regained consciousness. A definitive skull base reconstruction was done at the operating room at a later stage.

Conclusion:

The SEPS™, well-known for evacuation of CSDH, can be potentially used as a bed-side tool to effectively treat mass effect created by tension pneumocephalus. As a readily-available and commercially used device, it can provide a simple and standard toolkit suitable for an emergent temporizing procedure.

Pneumocephalus as result of nonsurgical peri-implantitis treatment with an air-polishing device for submucosal debridement-A case report

Background

A subcutaneous emphysema is an infrequent but potentially life‐threatening complication after dental treatment involving instruments functioning with pressurized air. Emphysemata after the use of high‐speed handpieces and air‐syringes are well documented, however, more recently several reports on emphysemata produced by air‐polishing devices during management of peri‐implant biological complications have appeared. To the best of our knowledge, direct development of pneumocephalus after a dental procedure has never been reported before. Introduction of air likely contaminated with oral bacteria to the intracranial space bares the risk of developing meningitis.

Case Presentation

This case report describes the spreading of a subcutaneous emphysema into the intracranial space (i.e., development of a pneumocephalus) after treatment of a peri‐implantitis lesion with an air‐polishing device equipped with the nozzle for submucosal debridement. A subcutaneous emphysema was noticed during the use of an air‐polishing device and the subsequent computed tomography (CT) examination revealed a quite unexpected spreading of the emphysema into the intracranial space. The patient was admitted to the hospital for close surveillance, CT follow‐up, and intravenous antibiotics to prevent the development of meningitis due to the introduction of air—likely contaminated with oral bacteria—into the intracranial space. After 3 days, the patient was discharged in good condition without any further complications.

Conclusion

In case of an extensive subcutaneous emphysema as result of a dental procedure, a more extended radiographic examination including the mediastinal and cranial space should be considered, to assess the risk for potentially life‐threatening complications.

Dynamics and diagnosis of severe pneumocephalus of unknown etiology in dog

Modern veterinary medicine and its subdivision – veterinary neurology, are constantly evolving. New diagnostic methods are emerging every day, and the list of new, previously unexplored animal diseases is expanding. Much information about the pathogenesis and etiology of diseases is borrowed from human medicine, which is a big problem, because human physiology is different from animals and, as a consequence, the dynamics of the disease are also different. That is why the continuous improvement of veterinary therapy and diagnosis of diseases is relevant and necessary. One of the rare and severe pathologies is pneumocephalus. It is reported that this is a condition in which there is a gradual accumulation of air in the cranial cavity or ventricles of the brain, creating a life-threatening condition. It is considered that pneumocephalus can occur spontaneously but, in most cases, is diagnosed after trauma or surgery with impaired integrity of the skull bones and meninges. This article describes a case of pneumocephalus of unknown etiology in a young dog who suffered a head injury while playing with the owner. During the neurological examination of the animal conducted immediately after the incident was diagnosed with severe central nervous system lesions (sopor, opisthotonus, tetraparesis); magnetic resonance imaging revealed significant brain damage with pronounced ventricular dilatation and the formation of a cavity filled with air. Re-diagnosis after 14 days showed progression of pneumocephalus with gas accumulation in the brain cavities. The contents of the ventricles have a division into liquid (cerebrospinal fluid), and air, progressive inflammatory processes in the brain's parenchyma were not observed; a fistula or canal connecting the cranial cavity and the external environment was not detected. Symptomatic and supportive therapy, carried out during the entire period of the dog's stay in the veterinary clinic, did not have positive results. The animal was euthanized according to medical indications and the owner's wishes.

Tension pneumocephalus following endoscopic resection of a mediastinal thoracic spinal tumor: A case report

BACKGROUND

Pneumocephalus is a rare complication presenting in the postoperative period of a thoracoscopic operation. We report a case in which tension pneumocephalus occurred after thoracoscopic resection as well as the subsequent approach of surgical management.

CASE SUMMARY

A 66-year-old man who received thoracoscopic resection to remove an intrathoracic, posterior mediastinal, dumbbell-shaped, pathology-proven neurogenic tumor. The patient then reported experiencing progressively severe headaches, especially when in an upright position. A brain computed tomography scan at a local hospital disclosed extensive pneumocephalus. Revision surgery for resection of the pseudomeningocele and repair of the cerebrospinal fluid leakage was thus arranged for the patient. During the operation, we traced the cerebrospinal fluid leakage and found that it might have derived from incomplete endoscopic clipping around the tumor stump near the dural sac at the T3 level. After that, we wrapped and sealed all the possible origins of the leakage with autologous fat, tissue glue, gelfoam, and duraseal layer by layer. The patient recovered well, and the computed tomography images showed resolution of the pneumocephalus.

CONCLUSION

This report and literature review indicated that the risk of developing a tension pneumocephalus cannot be ignored and should be monitored carefully after thoracoscopic tumor resection.

[Sitting position in neurosurgery: realizing the risks]

The author discusses potential intraoperative complications following neurosurgical interventions in sitting position: venous air embolism and paradoxical air embolism, postural hypotension, pneumocephalus, cervical flexion neuropathy, positional damage to peripheral nerves and others. Naturally, prevention of these complications is also considered, and the most effective approach is surgery in lying position.

MRI diagnosis of spontaneous intraventricular tension-pneumocephalus in a 10-month-old male Saarloos Wolfdog

A 10-month-old male Saarloos Wolfdog was presented with a history of multiple neurologic deficits that had acutely progressed. Neurologic examination findings localized signs to the cerebrum and brainstem. Magnetic resonance imaging revealed markedly enlarged and gas-filled lateral ventricles with a mass effect leading to cerebellar herniation. A right-sided defect of the cribriform plate with a dysplastic ethmoturbinate was identified as the inlet of air and origin of the intraventricular tension pneumocephalus. Surgical findings were consistent with a ruptured, congenital, nasal meningocele.

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.

Overlooked Piece of Wood Served as a Vector Transmitting Clostridium Perfringens: A Case Report Emphasizing the Awareness of Gas-Forming Organisms in Posttraumatic Pneumocephalus

ABSTRACT

The radiological depiction of posttraumatic pneumocephalus is due to trapped air in most cases. Although rarely reported, it can also be the result of a gas-forming organism, requiring immediate treatment due to high mortality. Here, we report on an elderly patient with radiological appearance of posttraumatic intracranial pneumocephalus after a wound was closed without recognition of a retained tree branch. The piece of wood served as a vector for transmission of Clostridium perfringens causing the collection of abnormal intracranial air. Radical excision of temporal muscle tissue along with extensive evacuation of the brain abscess and targeted intravenous antibiotics resulted in minor morbidity.Although a piece of wood can easily be missed with current diagnostic imaging, it is crucial that both clinicians and radiologists are aware of the presence of air and its differential diagnosis in posttraumatic pneumocephalus, in order to allow timely treatment in this fatal disease.

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.

Rare Case of Tension Pneumocephalus in Thoracic Trauma

Tension pneumocephalus is the presence of air within the cranial vault compressing the ventricles and the brain parenchyma. High altitudes can exacerbate this problem, especially when a dural defect exists and air is forced into the cranial cavity with no way to escape. This case demonstrates a rare presentation of thoracic trauma causing tension pneumocephalus due to emergent air evacuation.

Pneumocephalus with meningitis secondary to an old traumatic anterior cranial fossa defect

We report a case of a 30-year-old man who presented with altered mental status, fever, headache and vomiting for 3 days. An initial CT scan of the brain revealed the presence of pneumocephalus with a bony defect in the anterior cranial fossa. The pneumocephalus was not explained initially and the patient was re-examined for any signs of trauma to the face, and a review of the history revealed a series of three traumatic events months prior to this illness. Further laboratory studies revealed Streptococcus pneumoniae in the blood and bacterial meningitis. He was treated with antibiotics and was later taken up for endoscopic repair of the skull base defect. This case highlights the importance of recognising post-traumatic pneumocephalus with superimposed meningitis and sepsis months after a traumatic event to the skull base.

Delayed pneumocephalus induced by repeated percutaneous aspiration after spinal surgery: A case report and literature review

RATIONALE

Severe tension pneumocephalus can lead to drowsiness, coma, and even brain hernia and death. The occurrence of delayed pneumocephalus after spinal surgery is rarely reported and often ignored. Herein, we report a case of delayed pneumocephalus after repeated percutaneous aspiration following spinal surgery.

PATIENT CONCERNS

A 55-year-old man was admitted in October 2020 because of aggravation in bilateral lower limb weakness and dysuria for seven days. He was diagnosed with liver cancer a year ago, and he underwent several operations because of tumor recurrence. The patient underwent thoracic vertebrae tumor excision on this admission, and no cerebrospinal fluid leakage was discovered during surgery. After the third drainage by percutaneous aspiration, the patient complained of severe headache and vomiting on postoperative day 16.

DIAGNOSIS

Emergency brain computed tomography revealed massive pneumocephalus.

INTERVENTIONS

Thereafter, suction drainage was discontinued, and he was placed on bed rest and administered intravenous mannitol.

OUTCOMES

Repeated computed tomography showed complete resolution of the pneumocephalus after five days.

LESSONS

Wound exudates and cystic fluid after spinal surgery should be differentiated from cerebrospinal fluid leakage. Reckless percutaneous aspirations can form pneumocephalus in patients with an occult dural injury, and pneumocephalus can occur up to 16 days after surgery. Early diagnosis of pneumocephalus is crucial to avoid severe consequences.

Transorbital craniectomy for treatment of frontal lobe and olfactory bulb neoplasms in two dogs

CASE DESCRIPTION

An 8-year-old spayed female Shih Tzu crossbreed dog (dog 1) and a 13-year-old neutered male Miniature Fox Terrier (dog 2) were evaluated for removal of neoplasms involving both the frontal lobe and olfactory bulb.

CLINICAL FINDINGS

Physical examination revealed decreased menace response and behavioral changes in both dogs. For dog 1, neuroanatomic localization of the lesion was the left forebrain region; for dog 2, neuroanatomic localization of the lesion was the right forebrain region. Both dogs underwent CT, and dog 1 also underwent MRI. Results of diagnostic imaging were consistent with frontal lobe and olfactory bulb neoplasia in both cases. Dog 1 had lysis of the frontal bone adjacent to the neoplasm.

TREATMENT AND OUTCOME

Both dogs underwent a transorbital craniectomy to permit surgical tumor removal. Dog 1 was discharged from the hospital 48 hours after surgery, at which time its mentation and cranial nerve examination findings were considered normal. Dog 2 developed neurologic deterioration after surgery but was ultimately discharged from the hospital after 72 hours, at which time its mentation appeared normal.

CLINICAL RELEVANCE

The transorbital approach to the cranium provided excellent access to facilitate removal of frontal lobe and olfactory bulb neoplasms in these 2 dogs.

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.

Tension pneumocephalus following an implant removal from spine

Pneumocephalus is commonly seen after skull and maxillofacial fractures. It can also occur following cerebrospinal fluid leak after skull base surgery and epidural catheter placement. We report a rare case report of a 20-year-old man who developed tension pneumocephalus following implant removal from the spine. He responded well to the conservative treatment without any neurological complications.

Tension Pneumocephalus From an Eroding Cholesteatoma: A Case Report and Review of the Literature

Pneumocephalus is defined as the presence of air inside the cranial vault. Benign and tension pneumocephalus are different ends of the same disease spectrum. Tension pneumocephalus leads to the formation of a pressure gradient, requiring emergent surgical decompression to prevent herniation of the intracranial structures. In this report, we present a rare case of tension pneumocephalus with essentially benign radiological findings secondary to a ruptured cholesteatoma. The patient was a 64-year-old woman with a history of end-stage renal disease on hemodialysis and hypertension. She presented to the emergency department (ED) with acute-onset weakness and decreased mentation. Physical exam findings were consistent with a cerebrovascular accident (CVA). CT scan and CT angiogram (CTA) were unremarkable for ischemia or hemorrhage but showed signs of free intracranial air, consistent with the diagnosis of pneumocephalus. After the activation of the code stroke, neurosurgery and neurology were consulted. Worsening respiratory status led to a decision to proceed with emergent intubation, but it was held based on the family’s decision to proceed with comfort measures. The patient’s status declined further within minutes and she died. Afterward, the case was discussed with the radiologist, who interpreted the cause as a cholesteatoma that had eroded through the temporal bone.

A Rare Case of Temporal Bone Pneumocephalus Tracking through the Internal Auditory Canal

A 39-year-old male with chronic hydrocephalus requiring biventricular shunts presented with progressive pneumocephalus over several years. He showed no improvement following ventriculoperitoneal (VP) shunt revision and anterior skull base repair for a sphenoid dehiscence. Imaging continued to show worsening pneumocephalus with air tracking along the right facial nerve from the geniculate ganglion to the internal auditory canal (IAC). The patient then underwent tympanomastoidectomy and skull base reconstruction. Based on a search of published literature, this appears to be the first reported case of temporal bone pneumocephalus coursing through the IAC, unlike most cases associated with tegmen defects and middle fossa pneumocephalus.

Pneumococcal Otogenic Meningitis Complicated With Pneumocephalus and Coma State

We herein describe the unusual case of a male patient with pneumococcal otogenic meningitis, which was complicated with non-traumatic pneumocephalus and coma, in the absence of head trauma or a neurosurgical procedure. The initiation of an aggressive, empirical scheme with wide-spectrum antibiotics was achieved to stop the progression of meningitis, pneumocephalus, and their underlying causes in this patient. We propose pathogenetic mechanisms to explain this life-threatening condition.