**4.1 Cranioplasty flaps**

Cranioplasty is defined by replacing a missing bone flap, either by means of 3D printed material, autologous bone graft, bone cement or titanium mesh. Regardless of indications for performing craniectomy followed by cranioplasty, the infection rates for this neurosurgical procedure compared to the other procedures is higher. In a broad-based study in 2019 by Ying Chen et al., it was revealed that after craniotomies (6.58% Infection rate), cranioplasties had the highest infection rate (5.89%) in neurosurgical procedures [9]. Infections in cranioplasty procedures can occur early or late in the post-operative period. Early onset of infection usually appears with symptoms of meningitis and quite often wound oozing and surgical site infection is seen as well. PNM is a common complication after neurosurgical procedures, and this is also true for cranioplasty procedures too, if the symptoms cannot be treated by antibiotics, and the bone flap is the source of infection with or without wound oozing, then the flap should be omitted as soon as possible to prevent subdural empyema or abscess formation. Once the ongoing inflammatory process is treated after removal of the bone flap, a minimum of 2 months is recommended before a newer skull reconstruction surgery is performed.

#### **4.2 EVD**

External ventricular drains may be the most frequently used implant in neurosurgery. There are different types of ventricular drains with different impregnations which offer a lower risk for EVD related meningitis and ventriculitis. Antibiotic coated or ionized silver particles impregnated EVDs lower the risk of EVD related

*Infections in Neurosurgery and Their Management DOI: http://dx.doi.org/10.5772/intechopen.99115*

infections similarly to the administration of intraventricular antibiotics via the EVD, however there are multiple factors contributing to the infection of EVDs, such as existing infection, lack of proper tunneling of EVD, multiple CSF sampling, leakage and improper isolation of the surgical site by the nursing staff [10]. EVDs quite often are inserted at bedside by neurosurgeons in intensive care units (ICU), where the environmental bacterial composition is quite different and more resistant and severe in terms of contagiosity compared to other sections of a hospital, therefore there is a higher chance of EVD infection if it is placed at the bed side and in ICU and this can be prevented by performing this procedure in an operation room where sterility is maximized. If an EVD becomes infected or colonized, then it should be removed, and a newer drain should be inserted in a different location if needed.
