Step-Ladder Expansive Cranioplasty: A Study on a Cadaveric Model

Abstract

Notwithstanding the ongoing debates on the necessity, indication, extent, and technique of achieving decompressive hemicraniectomy (DC), any procedure that can deliver the envisaged advantages of a DC, without having to take up the patient for a second surgery in the form of cranioplasty, can be of a great advantage in situations in which DC is being used.Step-ladder expansive cranioplasty has been proposed as an effective single-step alternative to DC and cranioplasty at a later date, resulting in a fixed but assured volume augmentation. Recently, a case report has emerged documenting a successfully managed case of acute subdural hematoma (SDH) using this technique. In the present in vitro study, an attempt has been made to evaluate different variants of step-ladder expansive cranioplasty constructs using cadaver and clay models.The findings suggest that the cranial volume expansion in step-ladder expansive cranioplasty is not dependent solely on the patient's skull bone thickness. If the clinical trials prove the procedure to be safe, it can be used at one end, as an alternative to preserving the bone flap at another site prior to cranioplasty, and as a complete one-stage alternative to DC and cranioplasty at a later date, on the other.

Step Ladder Expansive Cranioplasty: A Novel Perspective in Cranial Volume Augmentation Surgery

“…For a defect of this size, the maximum distance from the imaginary line joining the craniectomy margins to the inner table in unoperated skull would be 1.45 cm. 9 Our computed tomography scanbased anatomical study closely replicated the study findings of Cavusoglu et al and our own mathematical model-based study. 8 The mean surface area of craniectomy defects in our anatomical study was found to be 66.89 cm 2 .…”

“…In the cadaveric study, we realized that the volume expansion was dependent more on the angulation of the titanium mini-plates and the length of the bridging portion of the mini-plate than the calvarial thickness. 9 First case of Step ladder expansive cranioplasty was performed in 2017 in a patient with traumatic brain injury. In axial noncontrast CT images, 12 cm  8 cm size craniectomy defect had a dural out-pouching of 28.1 mm (►Fig.…”