Nonmissile Penetrating Brain Injury Caused by Rebar: A Case Report

ABSTRACT

The primary treatment for a penetrating brain injury is craniotomy because of the presence of a foreign body. Craniocerebral computed tomography is the main imaging method for this condition, and cranial reconstruction is an important basis for formulating relevant surgical protocols. It is necessary to use antibiotics to prevent infection after surgery.

1. Introduction

A nonmissile penetrating brain injury caused by rebar is extremely rare, so a unified diagnosis or treatment standard is not available. This rare injury may lead to severe and even fatal brain damage, and it has a high mortality rate. This injury is often caused by accidents. Owing to its unique pathogenesis, the incidence of intracranial infections is extremely high. Here, we report a case of nonmissile penetrating brain injury caused by rebar. The patient underwent surgical treatment after admission and received antibiotic treatment after surgery. No neurological functional defects were found in the patient after 6 months of follow‐up.

Preoperative imaging is crucial for detecting and planning the surgical approach. Surgery is an effective treatment for this type of injury. However, owing to its rarity, there are no relevant clinical management guidelines. Given the rarity of this condition in neurosurgery, neurosurgeons are interested in methods to treat it.

2. Case Report

2.1. History

A 47‐year‐old male patient was admitted to the Neurotrauma Department of the First Hospital of Jilin University on June 5, 2023, due to rebar falling and penetrating the skull 1 h earlier. Physical examination upon admission revealed drowsiness. The Glasgow Coma Scale (GCS) score was 13 (E3V4M6). A piece of rebar inserted into the skull could be seen on the top of the head (Figure 1). The diameter of the bilateral pupils was 3.0 mm, and both the direct and indirect light reflexes were dull. His limb muscle strength was level 4, with normal muscle tension. The bilateral Babinski sign was negative. This finding suggests that there was no damage to the pyramidal tract. The patient was previously healthy. Brain CT on admission revealed a discontinuous bone structure in the right parietal bone and a very high‐density shadow locally extending into the brain through the right parietal bone, with radiating artifacts visible. Patch‐like high‐density shadows were observed in the parietal lobe below the inner plate of the skull (Figure 2). Laboratory examinations, such as blood count analysis, C‐reactive protein, and procalcitonin, were completed before surgery. The results revealed that the white blood cell count and the C‐reactive protein and procalcitonin levels were all greater than normal. The white blood cell count was 10.73 × 10⁹/L (4–10 × 10⁹/L). The C‐reactive protein was 144.57 mg/L (0–10 mg/L). Calcitonin was 0.1 ng/mL (0.000–0.046 ng/mL).

FIGURE 1.

The rebar inserted into the skull can be seen on the top of the head, with a large amount of rust on the surface of the rebar.

FIGURE 2.

A preoperative brain CT scan revealed a discontinuous bone structure in the right parietal bone, and a very high‐density shadow was locally observed extending into the brain through the right parietal bone, with radiating artifacts visible. Patch‐like high‐density shadows can be observed in the parietal lobe below the inner plate of the skull. (A) shows the location of the foreign body in the horizontal position (as indicated by the red arrow), (B) displays the location of the foreign body in the coronal position (as indicated by the red arrow), and (C) presents the location of the foreign body in the sagittal position (as indicated by the red arrow).

2.2. Methods

The patient was diagnosed with a nonmissile penetrating brain injury and underwent surgical treatment 2 h after admission. During surgery, a horseshoe‐shaped incision was made with the rebar at the center, and a milling cutter was used to free the bone flap for craniotomy. The osteogenic flap was approximately 12 × 10 cm long, with the lower edge reaching the skull base. The edge of the bone window was sealed with bone wax for hemostasis, and the dura mater was suspended. Bone fragments and rebar were observed penetrating the endocranium and entering the skull (Figure 3A). The surrounding hematomas were removed, and the rebar was removed after complete hemostasis. The cotton barrier protected the unaffected brain tissue during clearance. Bipolar electrocoagulation of the bleeding brain tissue was then performed. The diameter of the removed rebar was 12 mm, and it had penetrated approximately 4 cm into the brain. Brain contusions at the site of the rebar puncture, as well as a large amount of residual rust, were observed (Figure 3B). The rust and contaminants were thoroughly removed. After the foreign bodies were removed, the brain tissue was rinsed with normal saline. The skull was closed after ensuring that there were no residual foreign bodies or active bleeding.

FIGURE 3.

(A) After opening the bone flap, the rebar can be seen puncturing the endocranium and entering the skull. (B) Brain contusions and large amounts of rust residue can be seen at the puncture site of the rebar.

2.3. Results

Postoperative cranial CT revealed that the intracranial foreign bodies had been completely removed without any residue, and there was no secondary intracranial bleeding (Figure 4). Postoperatively, vancomycin was administered to control intracranial infection. Mannitol dehydration was applied to reduce cranial pressure, esomeprazole was administered to prevent stress ulcers, and sodium valproate was used to prevent epilepsy. On days 1 and 2 after surgery, the blood count and C‐reactive protein, and procalcitonin levels were higher than normal, but these tests returned within the normal ranges on day 3 after surgery. The results on the first day after surgery were: white blood cell count 10.9 × 10⁹/L (4–10 × 10⁹/L), C‐reactive protein 92.37 mg/L (0–10 mg/L), procalcitonin 0.14 ng/mL (0.000–0.046 ng/mL). The results on the second day after surgery were: white blood cell count 11.96 × 10⁹/L (4–10 × 10⁹/L), C‐reactive protein 45.53 mg/L (0–10 mg/L), procalcitonin 0.06 ng/mL (0.000–0.046 ng/mL).

FIGURE 4.

Postoperative cranial CT revealed that the intracranial foreign body had been completely removed without any residue, and no secondary intracranial bleeding was observed. (A) shows the bone flap removal area in the coronal position (as indicated by the red arrow), (B) shows the bone flap removal area in the sagittal position (as indicated by the red arrow), (C) shows the bone flap removal area after 3D CT reconstruction (as indicated by the red arrow), and (D) shows the bone flap removal area in the horizontal position (as indicated by the red arrow).

There was no fever or disturbance of consciousness after surgery; therefore, no etiological examination of the cerebrospinal fluid was performed. The patient recovered well and had no neurological sequelae after 6 months of follow‐up.

3. Discussion

Nonmissile penetrating brain injuries are open head injuries caused by the introduction of a foreign object into the brain. Nonmissile penetrating brain injuries caused by foreign bodies account for approximately 0.4% of all craniocerebral traumas [1]. Nonmissile penetrating brain injuries have a worse prognosis than closed craniocerebral injuries do [2]. The most common injury site is the roof of the orbit, followed by the squamous bone, due to the weakness of the associated bones. Nonmissile penetrating brain injuries are rare, with a complex pathogenesis. In this case report, the patient's injury site was the parietal bone, which is relatively rare and is related to the injury mechanism. Treatment depends on a combination of factors, such as the site of penetration, the object's trajectory, and whether the patient has an underlying disease [1].

Cephalometric radiographs and craniocerebral CT are the most suitable initial examinations [3]. Cephalometric radiographs can provide valuable information about the shape of the penetrating object and the site of the skull fracture [2]. They also have the advantage of not being affected by metal artifacts. Nonetheless, CT is the most useful imaging modality for making preoperative plans for nonmissile penetrating brain injuries. It can accurately delineate the associated skull fractures, provide information about the anatomical relationship between the object and the surrounding structures, and exclude any associated remote brain injuries [2]. Three‐dimensional constructed CT scans can provide further valuable information about the size, length, orientation, and angle of an object [2, 4]. Therefore, CT examination should be performed as soon as possible after such trauma because it can identify residual foreign bodies, the extent of the lesion, the locations of foreign bodies and bone fragments, and related lesions along the hematoma penetration path, and it can also provide useful information for the formulation of surgical procedures [5]. Therefore, we performed cranial CT and 3D‐constructed CT images of the patient. These examinations also provide a basis for determining the surgical plan. Compared with CT, brain MRI is superior in many fields. Notably, MRI may cause the movement of metal fragments and takes a longer time [4]. Because our patient's foreign body was metallic, it was not possible to perform a brain MRI. For patients suspected of having arterial injury or traumatic aneurysm, angiography, such as CT angiography, MRI angiography, or digital subtraction angiography, is strongly recommended [6]. Given that the intracranial foreign body in our patient was not near the intracranial vascular distribution area, angiography was not performed.

The surgical treatment of a nonmissile penetrating brain injury includes the removal of the foreign body, prevention and treatment of infection, management of vascular injury, removal of the hematoma, and reconstruction of the skull base [6]. Surgery aims to remove the object without worsening parenchymal or vascular cerebral lesions [7]. Therefore, removing the object blindly is not recommended, as this may further damage nerve tissue and adjacent blood vessels [8]. Surgical indications include the retention of foreign bodies, cerebrospinal fluid leakage, and vascular injury [6, 9]. Intracranial foreign body displacement typically occurs within a few hours after trauma, making it more difficult to remove the object surgically. Researchers have reported that intracranial foreign bodies should be accurately located and removed within 2–3 weeks after injury [6]. Those that are easier to remove are held in place by proliferating fibrous connective tissue or encapsulated by fibrous tissue [6]. Generally, the purpose of surgery is to remove foreign bodies and reconstruct the skull base [4, 10]. Some scholars believe that metal foreign bodies should not be removed if they are located in deep structures, are small in volume, or become life‐threatening during surgery. However, compared with other foreign bodies, lead bullets and skull fragments should be completely removed because of increased toxicity and infection [4, 10]. With respect to surgical timing, premature removal of foreign bodies may cause massive bleeding due to changes in pressure gradients, whereas delayed surgery tends to increase the risk of infection. Currently, surgical treatment is recommended within 12 h [5, 6]. Our patient underwent relevant preoperative examinations immediately after admission, and emergency surgery was performed within 12 h after injury to remove all the intracranial foreign bodies. During surgery, the tissues were carefully separated, and the foreign bodies were exposed. In addition, postoperative cranial CT confirmed the complete removal of the intracranial foreign bodies with no residual material and no complications, including secondary bleeding or cerebrospinal fluid leakage.

Early complications of nonmissile penetrating brain injury include brain parenchymal contusion, intracranial hematoma, dural tears associated with cerebrospinal fluid leakage, infection, and direct vascular injury [2, 11]. Advanced complications include pseudoaneurysms, foreign body migration, arteriovenous fistulas, and seizures [2, 12]. Given the severe brain contusion in the patient, brain swelling caused by the contusion as well as by intracranial infection would have occurred after surgery, subsequently leading to brain tissue compression and displacement. Therefore, a decompressive craniotomy was performed for the patient.

After a successful operation, it is necessary to pay attention to postsurgical complications. Infection is the main sequela of a nonmissile penetrating brain injury, with an overall incidence of 64%–70% and a mortality rate of 14%–57% [13]. Therefore, broad‐spectrum antibiotic therapy should be started after surgery. Third‐generation cephalosporins or vancomycin are typically administered. If bacterial culture results are available, the antibiotic application protocol can be adjusted according to drug sensitivity [14]. Staphylococcus aureus is the most common microorganism causing infections in this scenario. Therefore, we administered vancomycin to prevent intracranial infection after surgery, and the patient did not develop an intracranial infection. Gram‐negative bacilli are also often responsible for intracranial infections after nonmissile penetrating brain injuries [5]. The most common pathogens involved in abscess formation or meningitis reported in the literature are Streptococcus and Staphylococcus [5, 15] Nonetheless, owing to the fragility of bacteria in vitro, microbial cultures of abscess substances are negative in approximately 20% of patients [5, 16]. Our patient had no postoperative fever or changes in consciousness; therefore, an etiological examination of the cerebrospinal fluid was not performed.

Another postoperative complication that requires attention is epilepsy. The risk of traumatic epilepsy after a nonmissile penetrating brain injury is high, possibly due to direct traumatic injury to the cerebral cortex and subsequent brain scarring [5]. Recent studies have shown that excitability, neuroinflammation, oxidative stress, and neurodegeneration are predisposing factors for epilepsy [4]. Among all cases of nonmissile penetrating brain injuries, the incidence of traumatic epilepsy is 3.8%–4.2%. Therefore, antiepileptic drugs should be used prophylactically during the acute phase of the injury to reduce the incidence of posttraumatic epilepsy. Anticonvulsant therapy for up to 7 days is recommended to prevent the onset of early epilepsy [6]. In this context, we recommend antiepileptic therapy 7 days after surgery (Sodium valproate sustained‐release tablets 20–30 mg/Kg).

4. Conclusion

A nonmissile penetrating brain injury caused by rebar is an extremely rare condition. CT is the primary imaging method for nonmissile penetrating brain injuries. Surgical removal of foreign bodies and the application of postoperative antibiotics can improve patient prognosis and quality of life.

Author Contributions

Hang Xue: data curation, writing – original draft. Yubo Li: methodology, visualization, writing – review and editing. Weitao Zhang: supervision. Yujin Sun: investigation. Wei Li: investigation. Hongfa Yang: writing – review and editing.

Ethics Statement

The study was approved by the Ethics Committee of The First Hospital of Jilin University. All the patients provided their written informed consent.

Consent

Written informed consent was obtained from the patient to publish this report by the journal's patient consent policy.

Data Availability Statement

The datasets generated/analyzed during the current study are available.