Cerebrospinal Fluid Leak and Pneumocephalus as Consequences of Sneeze Suppression: A Case Report and Review of the Litrature

Introduction

Sneezing is a natural defence mechanism of your body. When dust, pollen, or germs irritate your nose, sneezing rapidly expels them, sometimes reaching speeds of up to 30 meters per second [1]. A burst of air exits through the mouth and nose when the trigeminal nerve activates the brainstem, causing the respiratory muscles to work together while the glottis is closed [1]. Although usually harmless, trying to suppress a sneeze by holding the mouth shut and pinching the nostrils prevents the normal release of intranasal and intrathoracic pressures, which then increase sharply and can be transmitted to nearby structures. Studies show that suppressing sneezing can increase intranasal pressure up to 20 times that of a normal sneeze, placing a person at risk for rare but serious complications affecting the otologic, ocular, thoracic, and central nervous systems [2].

Being infrequently encountered and usually reported as case reports, these injuries nonetheless raise clinical concern due to the serious potential complications that may develop. In a systematic review compiling sneezing-related injuries from 1945 to 2018, a total of 52 cases were documented in the literature, with 65% occurring in individuals without any detectable risk factors, indicating that even healthy people are at risk [2]. Although they have typically been associated with trauma or iatrogenic causes, intracranial complications like spontaneous cerebrospinal fluid (CSF) leaks and pneumocephalus are especially concerning when they occur without these factors [3]. A rare condition known as spontaneous pneumocephalus occurs when air accumulates inside the skull for no apparent reason, such as a head injury or brain surgery. It is typically caused by problems such as tumours, or defects in the skull base [4]. However, more recent data indicate that such events may be triggered by forceful Valsalva-like maneuvers, such as coughing, sneezing, and sneezing suppression [5–7].

The medical literature has documented a range of physiological effects associated with suppressing a sneeze. Rahiminejad et al reported that voluntary sneeze suppression can increase airway tract pressure by approximately 5 to 24 times normal levels, creating conditions capable of causing significant physiological injury [8]. Documented complications in the literature include cervical pain syndromes, inner ear injury with associated hearing loss, facial and cervical subcutaneous emphysema, and intracranial air accumulation [5,9–11]. A systematic review by Setzen et al analyzing sneeze-related injuries found that most reported cases occurred in male patients, with a subset of patients having pre-existing trauma or respiratory compromise [2].

Case reports reveal that forcefully suppressing a sneeze can introduce air into the cranial vault and potentially cause cerebrospinal fluid leakage [5,6]. In 1 documented case, a 24-year-old man developed subdural hemorrhage and pneumocephalus after 2 heavy sneezing episodes [6]. Another case suggested that frequent nose blowing and sneezing might mechanically cause sinus wall injury, enabling air introduction and CSF leakage [12].

While these findings are compelling, the evidence is based on isolated case reports, indicating these are rare but potentially serious complications that warrant medical attention if neurological symptoms occur after forceful sneeze suppression.

Herein, we report a case of 45-year-old woman with cerebrospinal fluid leak and pneumocephalus following sneeze suppression.

Case Report

A 45-year-old woman, previously healthy, was referred to the otorhinolaryngology–head and neck surgery outpatient clinic. She reported a 3-month history of mild holocephalic headaches that were somewhat alleviated by lying flat, as well as intermittent, watery, left-sided nasal discharge. The discharge occurred 3 times, most recently 3 weeks before presentation, was clear, and was provoked by leaning forward (a positive “reservoir sign”). She denied any history of head injuries, allergic rhinitis, chronic rhinosinusitis, or sinonasal surgery. There was no evidence of immunodeficiency, connective tissue disease, or intracranial pathology. Apart from occasional nasal obstruction, systemic evaluation was unremarkable.

On initial evaluation, neurological and general examination results were normal. Bilateral inferior turbinate hypertrophy and a septal spur on the left side were observed during anterior rhinoscopy; no active leak was present.

A high-resolution computed tomography (CT) scan (Figure 1A, 1B, 1D) demonstrated several small intracranial air locules consistent with pneumocephalus within the interhemispheric fissure and left frontal lobe. A 2-mm bony dehiscence of the left anterior cribriform plate with associated mucosal thickening was identified, along with a leftward C-shaped septal deviation and bilateral inferior turbinate hypertrophy. Magnetic resonance imaging (MRI) of the brain (Figure 1C) further supported the presence of intracranial air without additional parenchymal abnormalities.

As the patient showed no symptoms on the day of review and did not exhibit any signs of meningitis, she was discharged with explicit instructions to avoid Valsalva maneuvers and to return immediately if her symptoms worsened or if she developed a fever.

Over the following 6 weeks, the patient experienced 2 brief episodes of clear rhinorrhea, each lasting less than 30 minutes and triggered by bending forward. On 2 occasions during social gatherings, she continued to resist sneezing. She did not develop any new neurological deficits and remained afebrile.

At the 6-week follow-up visit, nasal endoscopy revealed clear fluid leak going to the left choana. To reduce CSF pressure, acetazolamide 500 mg was initiated twice daily, along with additional counselling on sneeze hygiene.

At approximately 8 weeks after initial presentation, the patient reported experiencing persistent rhinorrhea again despite medical treatment. Following interdisciplinary consultation, bilateral inferior turbinate reduction, septoplasty, and skull base repair of the left cribriform defect were conducted.

During preoperative evaluation, the anesthesia, neurosurgery, and ear, nose, and throat (ENT) teams held a preoperative briefing. Nasal culture, coagulation profile, and routine blood tests were all normal.

The patient subsequently underwent surgical intervention. The intraoperative findings included bilateral inferior turbinate hypertrophy, a deviated nasal septum, a minor encephalomeningocele at the left anterior cribriform plate, and an active CSF leak. After cauterizing the encephalomeningocele and removal of the surrounding mucosa, Surgicel dressing was applied, inferior turbinate mucosal graft was applied, further Surgicel was applied, then left middle turbinate septoconchopexy was done to stabilize the reconstruction.

Postoperatively, the patient spent 24 hours under observation in the high-dependency unit. She continued on 500 mg of acetazolamide twice daily. She experienced no headache, CSF leak, or neurological symptoms. After removing the packing on day 3, she was discharged with instructions to avoid heavy lifting, blowing her nose, and most importantly, any attempt to suppress her sneeze.

At follow-up visits conducted at 1, 2, 4, 6, 9, and 12 months after surgery, the patient displayed no symptoms. Flexible endoscopy showed that the repair site was well healed with no signs of leakage.. She was advised to sneeze with her airway open after being formally discharged from the joint ENT-neurosurgery follow-up. The patient’s clinical course is summarized in Figure 2.

Discussion

This case demonstrates that an important clinical lesson can be learned from sneeze suppression, specifically that it can serve as an uncommon yet clinically significant cause of spontaneous CSF leak and pneumocephalus. A 45-year-old woman experienced a headache and clear nasal discharge after an impulsively suppressed public sneeze, probably due to a desire to adhere to post-pandemic etiquette standards. Subsequent analysis revealed scattered pneumocephalus and a left cribriform plate defect, suggesting a cerebrospinal fluid leak from the skull base. The conservative use of acetazolamide in this case was ineffective, requiring further intervention. According to her follow-up, she had a well-healed skull following endoscopic repair, which involved bilateral inferior turbinate reduction, septoplasty, and a turbinate graft. After this procedure, she had no symptoms.

This case is similar to the report by Munshi and Ramakrishnan, which describes a 72-year-old woman who experienced severe headache and rhinorrhea after multiple episodes of sneeze suppression [5]. Imaging revealed pneumocephalus along with rupture of the olfactory bulb. Because of these findings, the patient required urgent surgical intervention involving burr hole placement and dural repair. Both cases were severe enough to necessitate emergency treatment. The common factor in each instance was the same: pressure generated during sneezing. In contrast, after medical therapy failed, our patient’s condition was subacute and managed electively. This difference highlights how the level of pressure, anatomical weakness, and timing of treatment can influence the range of complications from sneezing. These can range from mild, self-limiting symptoms to potentially fatal neurological emergencies [4,5].

Babl et al reported a similar case involving a 10-year-old girl who mimicked a Valsalva maneuver by pinching her nose and sneezing forcefully. This resulted in CSF rhinorrhea and pneumocephalus [13]. CT scans showed damage to the posterior sphenoid sinus, along with air in the sella and subarachnoid space. Initially, she was treated conservatively; however, she later required surgical intervention with placement of a fascia lata graft. The case of Babl et al focused on the posterior sphenoid sinus, a less common site for spontaneous CSF leaks. In contrast, our patient had a defect at the anterior skull base (cribriform plate). This suggests that, due to age-related changes or localized bone thinning, pressure-related injuries can affect multiple weak points along the base of the skull [13].

The claim here is supported by a case reported by Wu et al, in which a 54-year-old man experienced spontaneous pneumocephalus and subdural hemorrhage after a violent sneeze [6]. This patient had no history of sneeze suppression, unlike our patient, yet the event led to serious intracranial complications. This suggests that sneezing can be risky even without nasal blockage, particularly in individuals with connective tissue disorders or a thinning of the skull base. Additionally, lingering structural vulnerabilities may heighten susceptibility to such events. For example, Zhang et al reported a patient who developed diffuse pneumocephalus following sneezing after prior brain trauma [7].

Indeed, the fact that our patient had no known risk factors or history of trauma suggests that, in otherwise healthy individuals, simply suppressing a sneeze can generate enough pressure to cause a serious problem. Schuknecht and Witt provided further evidence through 2 cases of inner ear injury resulting in vertigo and deafness from suppressing a sneeze. They explained these injuries occurred due to pressure, with sudden changes causing the round or oval window to rupture [10]. These otologic injuries differ in location and mechanism, but all share a common fundamental cause: the abrupt passage of high-pressure airwaves through anatomical barriers. This supports the broader clinical understanding that multiple body systems can be affected when the body’s natural pressure-release mechanisms are disrupted [10].

Furthermore, Baba et al described a case of spontaneous pneumocephalus in a patient with no known cause that was connected to a nontraumatic CSF leak and was eventually treated surgically [4]. Similar to our patient, their patient did not exhibit typical risk factors, such as obesity or idiopathic intracranial hypertension, indicating a mechanical etiology. By lowering the risk of future pressure build-up during sneezing episodes, turbinate reduction and septoplasty, a preventative measure not frequently mentioned in prior reports, may have contributed to achieving a successful surgical outcome by reducing chronic nasal resistance [4].

In a recently published case report, a woman in her 50s presented with headache and clear rhinorrhea following sneezing and was diagnosed with pneumocephalus, which was successfully managed with conservative treatment alone. The authors attributed the condition to a sudden increase in intranasal pressure during sneezing, similar to the mechanism proposed in our case. However, unlike our patient, no persistent cerebrospinal fluid leak was identified, and surgical intervention was not required, highlighting the variable clinical presentation and management of sneeze-related intracranial complications [14].

All of these examples demonstrate that, despite being a socially acceptable gesture, the suppression of sneezing can have serious adverse health effects. Preventing these avoidable injuries requires increasing clinical and public awareness. When evaluating patients with spontaneous CSF leak or unexplained pneumocephalus, particularly if there has been no trauma or surgery, clinicians should ask about sneezing habits. A comprehensive approach that considers both the pathology and the underlying anatomical factors is exemplified by our successful outcome with combined functional and reconstructive endoscopic surgery.

Conclusions

Sneeze suppression is highlighted in this case study as an uncommon but clinically significant cause of pneumocephalus and spontaneous CFS leak. Understanding this mechanism may help diagnose patients with unexplained rhinorrhea or intracranial air more quickly if there is no history of trauma or previous surgery. Potentially dangerous complications may be avoided with better patient education and increased clinician awareness of safe sneezing techniques.