Comment on: “Timing of cranioplasty: is early surgery associated with increased complications and poor outcome?”

We thank Prasad and Menon for critically reviewing our article titled “Complications of cranioplasty after decompressive craniectomy for traumatic brain injury”, and sharing their experience. They are proponents of early cranioplasty (CP), and found that there was no difference in complications with respect to gender, operating time, cranioplasty material or timing of cranioplasty after decompressive craniectomy (DC). They mentioned that their findings are contrary to our results particularly with regard to timing of cranioplasty. We would like to bring to their notice that there are no prospective series or randomized control trials published and available in literature, which can approve or repudiate the benefits or even risks of early CP when compared to Late CP. Various Studies included and analyzed the outcomes of CP after DC done for a wide range of etiologies like trauma, stroke or tumors, in a combined fashion, without segregating these etiology cohorts. This heterogeneity certainly affects the conclusion. However, our study clearly mentioned the outcome of CP done after DC only for traumatic brain injury. We, also, precisely defined the duration of interval after DC. With this uniformity of indication and methodology, we reached the conclusion after application of standard statistical tests. We concluded that CP done after three months of DC had almost three times less chances of being affected by complications compared to when done within three months. In another series of 82 patients, it was concluded too, that CP carried out at a minimum of six months post DC limits the risk of infection significantly. In 280 CP procedures, Shuss et al. had clearly proved that patients who underwent early CP suffered significantly more often from complications compared to patients who underwent late CP (25.9% versus 14.2%; p1⁄4 .04). A recent metanalysis by Malcolm et al. (personal communication) looked for timing of CP and its relationship to complications. All were retrospective observational studies, comprising a total of 3126 patients (1,421 early versus 1705 late). They found that early CP had significantly higher odds of hydrocephalus than late CP (Odds Ratio [OR] 2.38, 95% Confidence Interval [CI] 1.25–4.52, p1⁄4 .008). There was no difference in complications with respect to gender, operating time, cranioplasty material or timing of cranioplasty after DC, reoperations, intracranial hemorrhage, extra-axial fluid collections, seizures or bone resorption. Subgroup analysis of trauma patients revealed a decreased odds of extra-axial fluid collection (OR 0.30, p1⁄4 .02) and an increased odds of hydrocephalus (OR 4.99, p1⁄4 .05). They concluded that early CP within 90 days after DC is associated with an increased odd of hydrocephalus than with later CP, but no difference in odds of developing other complications. Earlier cranioplasty in the trauma population is associated with fewer extra-axial fluid collections. However, this conclusion resulted from retrospective studies, and cannot yield strong evidence. Considering the lacunae in literature regarding timing of CP it is not surprising that our results differed from Prasad and Menon’s study. Future studies should determine optimal CP timing for specific patient populations, as well as appropriate management of hydrocephalus after early CP.