An unsuspected intracranial foreign body on the acute medical unit

Abstract

A 54-year-old man was referred to the acute medical unit with a suspected stroke after presenting to his general practitioner with altered speech, left sided facial droop and confusion. The patient had a new right sided swelling on the lateral aspect of his head but did not report any history of trauma. Imaging revealed a 9.2 cm nail entering via the right parietal bone with associated acute haemorrhage. After further discussion with the patient, he disclosed a suicide attempt with a nail gun 5 days prior to presentation. The nail was successfully removed by the neurosurgical team and the patient received rehabilitation and psychiatric assessment on the brain injury unit before going home.

Background

This case presents a rare event of a metallic intracranial foreign body caused by a self-inflicted nail gun injury in an attempted suicide. The clinical team had not managed such a situation previously and they successfully ensured that the patient was stable and transferred to the neurosurgical team for removal. Despite the severity of the injury, with removal of the foreign body and rehabilitation on the brain injury unit, the patient recovered well and was able to be discharged home. Reflection on this case demonstrates a number of learning points, including the importance of assessing for mental health issues on the acute medical unit.

Case presentation

A 54-year-old man presented with a 3-day history of altered speech (reduced verbal fluency), left sided facial droop and confusion. His symptoms had predominantly been noticed by his family who encouraged him to seek medical review; after assessment by his general practitioner, he was referred to the acute medical unit as a suspected stroke. The patient did not report any focal weakness, changes in sensation, visual changes or headache. He had not been systemically unwell. However, the patient and his family had noticed a ‘lump’ on the right side of the patient’s head; no history of trauma was recalled by the patient or his family. The patient had a medical history of hypertension and hypothyroidism. He was a non-smoker and worked as a self-employed mechanic. The patient’s family reported that they were concerned as his alcohol intake had increased to around 30 units a week, however, the patient reported he drank only minimal amounts of alcohol each week.

On examination, the patient was alert with a heart rate of 77 beats/min, blood pressure of 148/101 mm Hg, respiratory rate of 16 breaths/min and temperature of 37.8°C. Cardiovascular, respiratory and gastrointestinal examinations were unremarkable. Neurological examination revealed left sided facial weakness; it was otherwise unremarkable. The abbreviated mental test score was 8 out of 10 due to incorrect recall of age and street address (42 West Street). On the right lateral aspect of the patient’s head, there was a superficial firm swelling, around 1.5×1.5 cm, with no break in the skin and no erythema. No other injuries were noted on examination. The patient and the family reported that this was a new swelling.

Differential diagnosis

After initial assessment, the working diagnosis was a stroke due to an unknown trauma causing an intracerebral bleed. The main differential was encephalitis due to the history of confusion and low-grade fever on admission. Admission blood tests and an urgent CT head scan was arranged. A lumbar puncture was to be considered if the CT head was inconclusive.

Investigations

The urgent CT head scan report was very much unexpected and identified a large metallic intracranial foreign body (figure 1). The patient had a 9.2 cm nail entering the right parietal bone, crossing the junction of the lateral and third ventricles with the tip at the left caudothalamic junction, with hyperdensity in the frontal horn of the left lateral ventricle in keeping with acute haemorrhage (figure 2), and slight hyperdensity in the right frontal lobe suggestive of subarachnoid haemorrhage. There was no evidence of midline shift or hydrocephalus. There was soft tissue swelling and subgaleal haematoma overlying the right frontal bone. A CT reconstruction is shown in figure 3.

Figure 1.

Radiograph demonstrating intracranial nail.

Figure 2.

CT head demonstrating intraventricular haemorrhage.

Figure 3.

3D reconstruction of CT images.

Treatment

The patient was placed on neurological observations and moved to the resus bay for closer monitoring while the clinical team arranged urgent transfer to the local neurosurgical unit. The patient and his family were informed of the results; they were very shocked and distressed by the severity of the injury and how it had been inflicted. Further discussion revealed that in the preceding months the patient had been experiencing a very difficult time; he was low in mood due to a combination of personal events. The patient explained that 5 days prior to presentation he felt incredibly low and it ‘all got too much’; although he could not remember the specific details of the event, he suspects he attempted suicide with a nail gun.

The patient was transferred to the neurosurgical team; he was commenced on antibiotics, received tetanus prophylaxis and the nail was removed successfully. Once clinically stable, the patient was repatriated to the inpatient brain injuries unit at our centre for rehabilitation and psychiatry review. The rehabilitation involved daily assessment by the medical, occupational therapy and physiotherapy teams, and review by the neuropsychologists and psychiatric team one or two times a week. Neuropsychological assessment identified reduced verbal fluency, impairment of immediate and delayed memory, particularly for verbal information. Psychiatry review revealed that the patient had been struggling with low mood and had been experiencing suicidal thoughts, however, he regretted his attempt to end his life and did not express any further thoughts of self-harm or suicide. The patient improved with inpatient rehabilitation and was discharged home with crisis team follow-up and regular sertraline after 24 days on the brain injuries unit.

Discussion

Intracranial foreign bodies are infrequently encountered and reports in the literature suggest that such events are usually associated with deliberate self-harm and suicide,^1–3 criminal assault,² industrial accident² and suspected child abuse or infanticide attempts.^{4 5} The presence of an intracranial foreign body may not be initially suspected by patients and doctors due to an absence or limited number of symptoms, which may delay presentation to medical services and identification of the foreign body.^{6 7} Mental health issues such as depression affect a huge proportion of adults and episodes of self-harm in men have increased since 2007.⁸ This case demonstrates an unusual presentation of intracranial foreign body with absence of external evidence of a penetrating injury and symptoms suggestive of a stroke. With the benefit of hindsight, exploration of the patient’s social circumstances and mental health issues may have resulted in an earlier suspicion of attempted suicide, especially with consideration of the delay in presenting to medical services. Therefore, this case highlights the importance of exploring mental health issues and assessing risk for self-harm and suicide on the acute medical unit when mode of injury or symptom development is ambiguous.

Learning points.

• An assessment of a patient’s mental health status in the emergency setting when there is a delay in seeking medical advice and an ambiguous history may help broaden differential diagnoses and identify patient risk.

• Urgent neurological imaging in the acute setting can help identify serious injury and ensure patients are monitored and referred to the appropriate specialty.

• Patients with intracranial foreign body can present discretely with an unexpectedly low symptomology.