Pneumocephalus as a rare complication: a systematic review plus clinical vignette

Abstract

Introduction. Pneumocephalus is a clinical entity characterised by the presence of gas in the intracranial space. It can result from many different causes. The most common cause is head or facial trauma. Other causes include neoplasms, infections, and surgical or diagnostic procedures. Spontaneous non-traumatic pneumocephalus is a rare condition caused by bone defects, malformations, infections, tumours, intravenous air injection, and other causes. This review, supplemented with a case presentation, aims to summarise the current state of knowledge regarding non-traumatic pneumocephalus.Methodology. This review involved an electronic search (PubMed, Scopus, Embase, and Web of Science) to identify studies regarding non-traumatic pneumocephalus. In addition, reference lists of identified articles were screened for other potentially relevant papers.Results. In total, 1,107 articles were retrieved by searching databases with the selected query. Based on the selection process, 134 articles were included. These articles were then classified into 'otogenic' , 'bone defect' , 'malformations' , 'infectious' , 'tumours' , 'associated with intravenous air injection' , and other categories. Conclusion.Spontaneous non-traumatic pneumocephalus is a rare condition. Symptoms, clinical courses, and prognoses vary depending on the underlying cause of the disease. To the best of our knowledge, this review's example is the first case report of spontaneous pneumocephalus due to air embolism secondary to lung cancer.

Spontaneous rhinorrhea: a possible concealing initial symptom of ecchordosis physaliphora. Illustrative case

“…5,[17][18][19] This "locus of minor resistance" can lead to the formation of a pseudo-meningocele or a CSF leak into the nasal cavity, increasing the patient's risk of developing pneumocephalus and meningitis. 20,21 The patient may experience various symptoms, such as headache, stiffness in the neck, sensitivity to sound and light, and a decline in consciousness due to irritation of the meninges. Headache may also be caused by irritation of the dura mater by the tumor and intracranial pressure changes resulting from the fistula.…”

Otogenic Enterobacter cloacae meningitis complicated with pneumocephalus

“…Infection is a relatively common cause of spontaneous nontraumatic pneumocephalus. Among 140 cases of spontaneous nontraumatic pneumocephalus, 38 were associated with infections such as sinusitis, meningitis, subdural empyema, and osteomyelitis [ 1 ]. Among infectious conditions, meningitis accounted for 47.4% (18 cases), and the causative bacteria include Streptococcus pneumoniae , Bacteroides fragilis , Escherichia coli , Clostridium perfringens , Clostridium septicum , and Klebsiella pneumoniae .…”

“…Pneumocephalus refers to a pathologic collection of gas within the cranial cavity and is mostly caused by head trauma and neurosurgery. Spontaneous nontraumatic pneumocephalus is a rare condition, and its etiologies include bone defect, congenital malformation, tumor, and infection [ 1 ]. Although very rare, bacterial meningitis has also been reported as an infectious cause of spontaneous pneumocephalus [ 2 ].…”

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

“…It is most commonly observed in subclinical range shortly after trauma or instrumentation of the spine or cranium. While rare, alternative origins include infections such as Klebsiella pneumoniae meningitis, or chronic otitis media, as well as congenital intracranial defects, intracranial neoplasm or iatrogenic complication from nasal Merocel packing for epistaxis 1–4. Clinical presentations of pneumocephalus range from being asymptomatic to external cerebral spinal fluid (CSF) leak, headache, nausea, vision changes, altered mental status, seizure, meningitis, lethargy, unsteady gait, hemiparesis, papilledema or coma 1 5.…”