Cranioplasty following ventriculoperitoneal shunting: lessons learned

Abstract

Objective Cranioplasty (CP) is considered as a straightforward and technically unchallenging operation; however, complication rates are high reaching up to 56%. Presence of a ventriculoperitoneal shunt (VPS) and timing of CP are reported risk factors for complications. Pressure gradients and scarring at the site of the cranial defect seem to be critical in this context. The authors present their experiences and lessons learned. Methods A consecutive series of all patients who underwent CP at the authors’ institution between 2002 and 2017 were included in this retrospective analysis. Complications were defined as all events that required reoperation. Logistic regression analysis and chi-squared test were conducted to evaluate the complication rates according to suspected risk factors. Results A total of 302 patients underwent cranioplasty between 2002 and 2017. The overall complication rate was 17.5%. Complications included epi-/subdural fluid collection (7.3%) including hemorrhage (4.6%) and hygroma (2.6%), bone graft resorption (5.3%), bone graft infection (2.0%), and hydrocephalus (5.7%). Overall, 57 patients (18.9%) had undergone shunt implantation prior to CP. The incidence of epi-/subdural fluid collection was 19.3% in patients with VPS and 4.5% in patients without VPS, OR 5.1 (95% CI 2.1–12.4). Incidence of hygroma was higher in patients who underwent early CP. Patients with temporary shunt ligation for CP did not suffer from complications. Conclusion CP in patients with a VPS remains a high-risk procedure. Any effort to understand the pressure dynamics and to reduce factors that may trigger the formation of a large epidural space must be undertaken.

The “springform” technique in cranioplasty: custom made 3D-printed templates for intraoperative modelling of polymethylmethacrylate cranial implants

“…As in our series, most of the patients with postoperative haematomas had distinct clinical risk factors for intracranial bleeding after cranioplasty. Ventriculo-peritoneal shunt placement (patient 7) has previously been described as a risk factor [ 8 ]. Coagulation disorders like a Factor XIII deficiency (patient 6) or the vital need for early anticoagulation (patient 11) certainly played a crucial role in the postoperative intracranial haematomas that occurred in our series.…”

Outcome and risk factors of complications after cranioplasty with polyetheretherketone and titanium mesh: A single-center retrospective study

“…However, Schuss ( 32 ) and Heo ( 33 ) recommended that shunt operation and repair should be performed at different stages rather than concurrently in patients requiring VPS, which significantly reduces postoperative complications. Hirschmann ( 31 ) and Meyer ( 34 ) reported no significant difference in the incidence of complications between the two groups. A recent study comparing effect of concurrent vs. staged VPS and CP suggests no significant difference in infections, resorption, and implant failure, although implant failure and hospital-acquired infection were lower in concurrent VPS group.…”

“…According to our results, a history of ventriculoperitoneal shunt (VPS) before CP was an independent risk factor for early overall complications, increasing the early complication rate of CP. Hirschmann ( 31 ) reported a significant increase in the incidence of epidural/subdural effusion and epidural/subdural hematoma in patients who underwent VPS before surgery. As for the reason, patients with a previous VPS are more likely to have skin flap depression, increasing the difficulty of exposing the dural scar layer with repeated contusion and stretching of subdural contents, leading to the risk of subdural hemorrhage and disturbance of cerebrospinal fluid (CSF) circulation, which facilitates the formation of epidural and subcutaneous effusions ( 31 ).…”

“…Hirschmann ( 31 ) reported a significant increase in the incidence of epidural/subdural effusion and epidural/subdural hematoma in patients who underwent VPS before surgery. As for the reason, patients with a previous VPS are more likely to have skin flap depression, increasing the difficulty of exposing the dural scar layer with repeated contusion and stretching of subdural contents, leading to the risk of subdural hemorrhage and disturbance of cerebrospinal fluid (CSF) circulation, which facilitates the formation of epidural and subcutaneous effusions ( 31 ). Therefore, adjusting the amount and speed of drainage seems important; a programmable valve to reduce the volume of CSF drainage was suggested, and the patient's upper body should be positioned as flat as possible after surgery, with temporary ligation and shunt also being considered.…”

Outcomes of Cranioplasty: A Single-Center Experience

“…The rate of each complication and the related risk factor varies considerably in the literature with infection as the most occurring in one study (53.21% out of the total complication rate 10.9), and BFR in another (54.7% out of the total complication rate 36%) [ 7 , 10 ]. In addition, several predictive parameters have been correlated with some of the complications such as the material being used, the location of the skull defect, and the presence of a ventriculoperitoneal (VP) shunt at the time of CP [ 11 - 13 ]. Nevertheless, there is still inconsistency and variation regarding these predictive factors in the literature [ 14 ].…”