Causes of pneumocephalus and when to be concerned about it

Imaging Findings in Acute Traumatic Brain Injury: a National Institute of Neurological Disorders and Stroke Common Data Element-Based Pictorial Review and Analysis of Over 4000 Admission Brain Computed Tomography Scans from the Collaborative European NeuroTrauma Effectiveness Research in Traumatic Brain Injury (CENTER-TBI) Study

In 2010, the National Institute of Neurological Disorders and Stroke (NINDS) created a set of common data elements (CDEs) to help standardize the assessment and reporting of imaging findings in traumatic brain injury (TBI). However, as opposed to other standardized radiology reporting systems, a visual overview and data to support the proposed standardized lexicon are lacking. We used over 4000 admission computed tomography (CT) scans of patients with TBI from the Collaborative European NeuroTrauma Effectiveness Research in Traumatic Brain Injury (CENTER-TBI) study to develop an extensive pictorial overview of the NINDS TBI CDEs, with visual examples and background information on individual pathoanatomical lesion types, up to the level of supplemental and emerging information (e.g., location and estimated volumes). We documented the frequency of lesion occurrence, aiming to quantify the relative importance of different CDEs for characterizing TBI, and performed a critical appraisal of our experience with the intent to inform updating of the CDEs. In addition, we investigated the co-occurrence and clustering of lesion types and the distribution of six CT classification systems. The median age of the 4087 patients in our dataset was 50 years (interquartile range, 29-66; range, 0-96), including 238 patients under 18 years old (5.8%). Traumatic subarachnoid hemorrhage (45.3%), skull fractures (37.4%), contusions (31.3%), and acute subdural hematoma (28.9%) were the most frequently occurring CT findings in acute TBI. The ranking of these lesions was the same in patients with mild TBI (baseline Glasgow Coma Scale [GCS] score 13-15) compared with those with moderate-severe TBI (baseline GCS score 3-12), but the frequency of occurrence was up to three times higher in moderate-severe TBI. In most TBI patients with CT abnormalities, there was co-occurrence and clustering of different lesion types, with significant differences between mild and moderate-severe TBI patients. More specifically, lesion patterns were more complex in moderate-severe TBI patients, with more co-existing lesions and more frequent signs of mass effect. These patients also had higher and more heterogeneous CT score distributions, associated with worse predicted outcomes. The critical appraisal of the NINDS CDEs was highly positive, but revealed that full assessment can be time consuming, that some CDEs had very low frequencies, and identified a few redundancies and ambiguity in some definitions. Whilst primarily developed for research, implementation of CDE templates for use in clinical practice is advocated, but this will require development of an abbreviated version. In conclusion, with this study, we provide an educational resource for clinicians and researchers to help assess, characterize, and report the vast and complex spectrum of imaging findings in patients with TBI. Our data provides a comprehensive overview of the contemporary landscape of TBI imaging pathology in Europe, and the findings can serve as empirical evidence for updating the current NINDS radiologic CDEs to version 3.0.

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.

Traumatic pneumocephalus as a possible early sign of acute spinal cord injury: Case report

Background

Traumatic pneumocephalus (TPC) following craniofacial injuries is common, but isolated TPC secondary to pneumorrhachis (PR) is the rare result of upward gas migration from the spinal canal. In the absence of craniofacial and grossly unstable spinal fractures, the etiology of TPC in polytrauma can be elusive and an underlying diagnosis of acute spinal cord injury (SCI) can be easily missed. We report the first polytrauma case where TPC was the most reliable early sign of SCI.

Case Description

A 34-year-old polytrauma female with imaging findings of TPC, which was later found to be secondary to an underlying SCI. As a focused exam could not be performed at admission, the TPC was first attributed to undiagnosed craniofacial injuries. Tertiary survey revealed the patient being paraplegic and MRI workup demonstrated an acute SCI at the T3-T4 level. PR was the most likely cause of TPC in the absence of other craniofacial injuries.

Outcome

The patient did not have a meaningful recovery given the extensive hemispheric infarcts, spinal cord injury, and respiratory failure.

Conclusions

Although uncommon, TPC may be an important radiographic sign suggesting the possibility of an underlying SCI in polytrauma patients. especially when focused neurologic assessment is limited at admission. Polytrauma patients with TPC and PR in the absence of coexisting craniofacial fractures require an urgent spine consultation by the ER physician, with possible early spine MRI workup. We suggest a diagnostic algorithm for the early identification of SCI in polytrauma patients presenting with TPC and propose considering 3 groups which may have different risks for SCI based on their clinical presentation and the presence of PR.

Pneumorrhachis Secondary to a Locally Advanced Rectal Cancer with Pre-Sacral Abscess-Case Report and Review

The occurrence of pneumorrhachis (PR), defined as the presence of air within the spinal canal, presents a complex clinical picture with diverse etiological factors. We report an exceedingly rare case of PR arising from locally advanced rectal cancer accompanied by a pre-sacral abscess. This report aims to enhance awareness and understanding of rare causes of PR within the medical community, particularly among surgeons engaged in emergency procedures. The patient survived the acute phase of the disease through multiple surgical interventions and admission to the intensive care unit, but succumbed to cardiovascular complications three weeks later. We also offer a brief review of the literature concerning PR originating from the colorectal lumen.

Code Stroke Postendoscopy: A Case of Pneumocephalus From a Spinal-Esophageal Fistula

Esophageal fistula to the respiratory tract and mediastinum is a well-described complication from esophageal malignancies. Spinal-esophageal fistula (SEF) on the other hand is a much rarer complication that has only been reported in few instances. Here, we report a unique case of fatal spinal-esophageal fistula with an associated pneumocephalus in an 83-year-old woman with metastatic esophageal squamous cell carcinoma.

Pneumocephalus Secondary to Cerebral Air Embolism After Acute Bleeding in an Emphysema Bulla

Pneumocephalus is the presence of air in the intracranial space and has multiple causes, including cerebral air embolism. Its presentation may range from asymptomatic to decrease mental status, coma, and seizures. We present a case of cerebral air embolism secondary to acute bleeding inside an emphysema bulla. A 69-year-old female was brought to the emergency room after suffering acute dyspnea, convulsions, and cardiac arrest during a commercial flight. The Head CT showed the presence of multiple small gas collections in the brain, and the Thoracic Angiotomography showed a thin-walled bulla surrounded with pulmonary venous vascular structures and signs of active bleeding. The patient had rapid neurological deterioration with evolution to brain death due to anoxic encephalopathy before the possibility of treatment with pulmonary lobectomy and hyperbaric oxygen therapy. It is important to identify the localization of pneumocephalus to determine its etiology and to deliver the best treatment. Cerebral air embolism may happen when air enters the arterial or venous system, which can cause brain damage due to capillary leak syndrome and local ischemia. Treatment of pneumocephalus includes treating the cause, bed rest, avoidance of Valsalva maneuvers, positive pressure, and hyperbaric oxygen therapy. Early recognition is essential to prevent complications such as irreversible brain lesions and to improve patient outcomes.

Pneumocephalus; a rare cause of coma

We report the case of an 84-years old female patient who developed cerebral air embolism in association with the indwelling hemodialysis central venous catheter. Pneumocephalus, even though rare, should be included in the differential diagnosis of acute manifestation of neurologic deficits, especially in association with central venous access, surgical interventions or trauma, and requests prompt management. Brain computed tomography scanning remains the investigation of choice.

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.

Persistent Air Embolism after Blunt Chest Trauma with Recovery to Pre-Existing Consciousness Level: A Case Report and Literature Review

We report the case of a 71-year-old woman in whom cerebral air embolism resulted from blunt chest trauma. The woman had been lying on her left side for a while after the injury, and air traveled to the right side of the brain. As a result, a cerebral infarction occurred in the right cerebral hemisphere that caused loss of consciousness for more than 40 days. The patient recovered consciousness eventually; thus, it is important to monitor the improvement in a patient's state of consciousness, with repeated multi-modality imaging evaluations over a long period.

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.

A rare case of Escherichia coli and Rhizopus sinusitis complicated with pneumocephalus, E. coli psoas abscess and sepsis

Sinusitis is a common ailment a clinician comes across in their day-to-day practice. Simple as it may sound, it may become a very debilitating condition depending on the comorbidities of the patient and the organism involved. Rhizopus and Escherichia coli are less common organisms to affect the sinuses, but they are more common in immunocompromised patients such as patients with uncontrolled diabetes. Rhizopus can be a very debilitating infection as it erodes into the bone and blood vessels resulting in tissue necrosis. However, coinfection of both of these organisms is a very rare occurrence. Psoas abscess is also a less common infection in the immunocompetent patients but it is more common among the immunocompromised patients. It is extremely rare for both of these organisms to cause sinusitis in one patient, and for E. coli to simultaneously infect two different sites in the same patient. We report a case where a diabetic patient who had E. coli and Rhizopus coinfected sinusitis with simultaneous E. coli psoas abscess was successfully managed. The Rhizopus was treated with liposomal amphotericin B for 16 weeks while E. coli was treated with IV Meropenum. Furthermore, pneumocephalus is a condition that usually occurs following head trauma but the patient we are reporting developed pneumocephalus following Rhizopus sinusitis, which was treated with high-flow oxygen.

Traumatic Pneumocephalus Without Skull Fracture From a High-Voltage Electrical Injury

Pneumocephalus, the presence of intracranial air, most commonly occurs secondary to a traumatic injury. Patients with simple pneumocephalus often present with nonspecific symptoms or with headaches. These patients may have little to no clinically relevant physical examination findings and can be managed conservatively. Tension pneumocephalus can present more acutely as a neurosurgical emergency. On physical examination, patients can present with neurologic deficits or papilledema. Computed tomography is the imaging modality of choice to detect intracranial air. We present a novel case of a simple pneumocephalus in the setting of a high-voltage electrical injury without evidence of displaced skull fracture or dural violation. The identification of unanticipated air within the cranial vault should prompt emergency physicians to determine its etiology which can guide treatment and disposition.

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.

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.

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.

Findings of subarachnoid fat after trauma to a tarlov cyst

Subarachnoid fat is an uncommon finding that has several etiologies. It is important to determine the etiology in order to plan appropriate treatment. We present a case report of an 80-year-old female brought to the emergency department after a fall with complaints of headache and pain in the sacral region. Computed tomography and magnetic resonance images of the head demonstrated fat in the subarachnoid space. Computed tomography and magnetic resonance images of the sacrum demonstrated a Tarlov cyst with a sacral fracture extending into the cyst, likely representing the origin of the fat in the subarachnoid space. This case demonstrates a rare etiology of fat in the subarachnoid space.

Unilateral blindness following superior laryngeal nerve block for awake tracheal intubation in a case of posterior cervical spine surgery

Background:

Superior laryngeal nerve block (SUPLANEB) is a popular airway anesthesia technique utilized for successful awake endotracheal intubation in patients with significant cervical spine instability. If not performed by an expert, it carries the risk of general/neurologic complications that are typically minimal/transient. However, permanent blindness and/or upper cranial nerve neuropathies may occur. Here, we describe a case in which a young patient underwent an atlantoaxial fusion for a C2 nonunion (e.g., following a fracture) complicated by unilateral blindness due to a SUPLANEB.

Case Description:

A 25-year-old neurologically intact male underwent a C1-C2 posterior arthrodesis to address a nonunion of a C2 fracture. To perform the awake nasotracheal intubation, a SUPLANEB was performed using a video laryngoscope. Although the operation was uneventful, postoperatively, the patient reported left visual loss accompanied by left-sided facial numbness and hearing loss. On examination of the left eye, the anterior segment and fundus examinations were normal, but the OCT (optical coherence tomography) and retinal angiography demonstrated left-sided postischemic retinal edema with permeability of the intraocular vessels. Although the cranio-orbital computed tomography scan showed only mild pneumocephalus, the CT angiogram scan revealed abnormal air in the left carotid sheath accompanied by diffuse subcutaneous emphysema. Further, brain and orbital magnetic resonance imaging scans were normal. The patient was treated with pure oxygen, systemic steroid therapy, and nimodipine. The pneumocephalus and subcutaneous emphysema resolved on day 3. At 2 months follow-up, the patient remained blind on the left side, but had no further neurological deficits.

Conclusion:

Blindness and upper cranial nerves neuropathies should be considered as potential complications of SUPLANEB. Notably, these deficits were not directly related to the operative positioning or neurosurgical spinal procedure.

Significance of intracranial gas on post-mortem computed tomography in traumatic cases in the context of medico-legal opinions

The detection of intracranial gas (ICG) in people who died due to trauma became possible once postmortem computed tomography (PMCT) became available in addition to traditional post-mortem examinations. The aim of this study was to determine the importance of ICG in the context of medico-legal opinions. We assessed 159 cases of trauma-induced death. Cadavers with pronounced signs of decomposition, open skull fractures, and after neurosurgical operations were excluded. Both PMCT findings and data from autopsy reports were analyzed. ICG was found in 38.99% (n = 62) of the cadavers, 96.77% (n = 60) of which presented with pneumocephalus (PNC) and 40.23% (n = 25) with intravascular gas (IVG). There was a strong correlation between ICG and skull fractures/brain injuries, as well as chest injuries, especially lung injuries. In 13 cases, ICG presented without skull fractures; three of these cases died as a result of stab and incised wounds to the neck and chest. The mean time between trauma and death was significantly longer in the non-ICG group than the ICG group at 2.94 days (0–48 days) and 0.01 day (0–1 day), respectively (p < 0.0001). The presence of ICG is a result of severe neck and chest injuries, including stab and incised wounds. The victims die in a very short amount of time after suffering trauma resulting in ICG. The ability to demonstrate ICG on PMCT scans can be of significance in forming medico-legal opinions.

Assessment of Explicitly Stated Interval Change on Noncontrast Head CT Radiology Reports

BACKGROUND AND PURPOSE

Consistent and standardized reporting of interval change for certain diagnoses may improve the clinical utility of radiology reports. The purpose of this study was to assess explicitly stated interval change of various findings in noncontrast head CT reports.

MATERIALS AND METHODS

A retrospective review was performed on successive noncontrast head CT radiology reports from the first 2 weeks of January 2014. Reports with at least 1 prior comparison CT scan were included. Reports with normal examination findings and those that made comparison with only other types of examinations (eg, MR imaging) were excluded. Descriptive and subgroup statistical analyses were performed.

RESULTS

In total, 200 patients with 230 reports and 979 radiographic findings were identified. The average interval between reports was 344.9 ± 695.9 days (range, 0-3556 days). Interval change was mentioned 67.3% (n = 659) of the time for all findings (n = 979). Explicitly stated interval change was significantly associated with nonremote findings (P < .001) and generalized statements of interval change (P < .001). The proportion of interval change reported ranged from 95.3% of the time for hemorrhagic to 36.4% for soft-tissue/osseous categorizations.

CONCLUSIONS

Interval change reporting was variable, mentioned for 67.3% of noncontrast head CT report findings with a prior comparison CT scan. Structured radiology reports may improve the consistent and clear reporting of interval change for certain findings.

Effective but uncommon treatment of a spontaneous otogenic epidural pneumocephalus

We describe an uncommon treatment for epidural pneumocephalus and an effective but uncommon treatment option. Complete and permanent relief was achieved in a young patient using a tympanostomy tube to eliminate excessive positive air pressure in the mastoid bone that was the cause of spontaneous pneumocephalus. The patient showed no recurrence and absence of clinical symptoms at outpatient follow-up. Post-traumatic, infectious or spontaneous pneumocephalus may require an active, usually surgical approach. Treatment with a tympanostomy tube can be an alternative in suitable patients.