Retained intracranial splinters : a follow up study in survivors of low intensity military conflicts.

HS Bhatoe 
 Department of Neurosurgery, Command Hospital (CC), Lucknow - 226002, India., India

Correspondence Address:
H S Bhatoe
Department of Neurosurgery, Command Hospital (CC), Lucknow - 226002, India.
India

Full Text

::   Introduction

The literature on missile injuries of the brain sustained

in war is more extensive than the one dealing with

such injuries sustained during peacetime. While high

velocity missile injuries (HVMIs) are almost

invariably fatal, majority of the survivors would have

sustained low velocity missile (LVM) injuries. Source

of LVMs is generally a shrapnel from a grenade,

rocket or improvised explosive device (IED) etc. With

rapid evacuation of such patients to neurosurgical

centres, availability of computed tomography (CT),

improved understanding of missile ballistics and

better neurosurgical techniques and postoperative

care, there has been overall improvement in the

survival of these patients. This has also resulted in

more survivors with retained intracranial splinters,

who have been followed up over a period of years and

the sequelae and outcome of retained splinters have

been analysed. We present our observations in 43 such

patients with retained intracranial splinters. Relevant

literature is briefly reviewed.

::   Material and methods

A total of 18 patients with low velocity missile

injuries (LVMIs) of the brain were seen among the

Indian Army personnel during Sri Lanka operations in

1987-1989, and 92 patients were treated in Jammu

and Kashmir from 1990-1996.[1] The sources of

missiles were IEDs, grenades, rockets and rifle

bullets. There were 28 orbitocranial and two frontoorbitomaxillary

injuries. All the injuries were

supratentorial.

Assessment and Initial Management : Patients were

evacuated to the nearest Base Hospital after the injury,

within half an hour to more than 24 hours. Triage was

carried out and priority allotted. After resuscitation,

patients with brain injuries were neurologically

evaluated; this examination formed the baseline for all

subsequent neurological evaluation. Head was shaved

and open wounds were dressed. Intravenous mannitol,

frusemide and antibiotics were administered. All

patients had skull radiographs taken. CT brain could

be done in 23 patients before surgery.

::   Results

Initial Surgery : Ninety patients underwent surgery.

Eight patients died in the hospital prior to surgery, and

nine patients with small puncture wounds and no

neurological deficit, were not operated upon and

followed up. Craniectomy was done at the site of

entry/exit wounds. Debridement was done till normal

looking brain was seen and cavity did not collapse.

Metallic splinters were removed only if they were

seen during the course of debridement.

Retained Intracranial Splinters : Forty three survivors

had retained intracranial splinters. Out of these, in the

postoperative period, two patients with orbitocranial

injury and ten patients with skull vault injury had CSF

leak from the wound for a period of 3-12 days. The

distribution of these patients is as given in [Table I].

These patients have been followed up for over a

period varying between one year to ten years. Nine

patients (two non-operated cases with puncture

wounds and seven operated cases) were lost to follow

up. The sequelae of retained splinters in the remaining

34 is as given in [Table II]. It is observed that three out

of four patients with orbitocranial injury and 7 out of

30 cases with skull vault injury had suppurative

sequelae. Recurrent meningitis was followed by

hydrocephalus, which required ventriculoperitoneal

shunting. In one of these patients with puncture

wound and no neurological deficit, there was

intraventricular lodgement of the splinter [Figure 1].

Brain abscess was seen in two cases who earlier had

recurrent bouts of meningitis [Figure 2]. Abscesses were

excised in both the cases together with the retained

missile fragments, which was seen adherent

to/embedded in the abscess wall. No abscess was seen

in skull vault group. One of these, however, developed

temporal lobe seizures requiring antiepileptic

medication. These patients are being followed up and

have remained stable. No sequelae have been noted in

the remaining 23 patients with retained intracranial

splinters on follow up [Figure 3] and [Figure 4].

::   Discussion

In the past, military neurosurgeons believed it was

imperative to remove all intracranial bone and metal

pieces in a patient with splinter injury of the brain.

Reoperation was advocated if retained fragments were

evident after initial debridement.[2],[3] One of the

primary histological concerns with a less aggressive

approach has been the fear of intracerebral abscess

formation.4 Martin and Campbell5 recorded a

parenchymatous infection rate of 16% based on their

World War II experience. They believed that infection

was 10 times more likely to occur in the presence of

retained bone fragments than in their absence.

Nevertheless, the complication rate of secondary

procedures is high and consists of increased

neurological deficit, enhancement of cerebral oedema,

infection and deaths.

Others[6],[7],[8] have advocated a more conservative

approach. Brandvold et al[6] reported 83 patients with

splinter injury to brain with retained metal or bone

fragments. At follow up, there were no suppurative

sequelae. The low incidence of brain abscess and

inconsistent presence of retained fragments in patients

presenting with abscess has been confirmed by the

Vietnam head injury study (VHIS).[9] In an analysis of

127 war inflicted missile injuries sustained in North-

Eastern Croatia, Vrankovic et al,[10] reported an

incidence of retained fragments in 76.8% of the

patients, with intracranial infection rate of 10% in

these patients. In a recently concluded exhaustive

study on splinter injuries to brain during Iran-Iraq

war,11 it has been brought out that retained bone and

metal fragments were less important factors in CNS

infections after military head wounds.

The factors consistently leading to suppurative

complications are:-

a) Facio-orbital wound of entry, traversing the air

filled sinuses :The intracranial contents are in

communication with potentially infected mucus

secreting spaces, with higher risk of intracranial

sepsis.

b) CSF leak : Persistent CSF leak, especially more

than 24 hours old, is fraught with danger of meningitis

and ventriculitis.

c) Intraventricular lodgement of the missile fragment.

Although the possible epileptogenic effects of

retained metal fragments - especially copper - have

been mentioned,[12] there is no definite indication for

pursuing metallic fragments beyond those that are

readily accessible. The single exception is metallic

migrating fragment. Intraparenchymal bullets

generally do not migrate; intraventricular fragments

are the ones that do and these should be removed by

endoscopic manoeuvers or by stereotaxy.[13]

::   Conclusion

With improvement in evacuation of patients with

missile injury to the brain, better understanding of the

pathology, improved imaging modalities, surgical

facilities and postoperative care, there will be more

patients surviving the initial injury. Missile fragments

need not be specially searched for during debridement

so as to avoid aggravation of neurological damage.

The fragments should be removed only if they are

visible. Retained intracranial fragments do not,

predispose the patient to suppurative complications.

On the other hand, other factors like postoperative

brain swelling and CSF leak, orbitocranial trajectory

and intraventricular lodgement are associated with

increased incidence of such complications. Patients

with retained intracranial missile fragments should be

on regular follow up so that such complications are

recognized and treated as they occur.

References