31 Trauma Flap and Osteo-Dural Decompression Techniques • Acute subdural hematomas. • Decompressive hemi-craniectomy for trauma or stroke with unilateral hemisphere swelling and midline shift. • Position: Patient is positioned supine. • Head: The head is flexed 10–15°, rotated 45° to the contralateral side (if no contraindications). • In case of unstable cervical spine: hard collar has to be kept with ipsilateral shoulder roll; alternatively, the patient might be placed in the lateral position to keep neck in neutral position. • Axillary roll is placed under the contralateral axilla. • Ipsilateral shoulder is pulled down to maximize the opening between head and shoulder. • Reverse question-mark incision (Fig. 31.1) ◦ Starting point: Incision starts at the zygomatic arch, < 1 cm anterior to the tragus. ◦ Run: Incision line runs superiorly and then curves posteriorly at the level of top of the pinna till 4-8 cm behind the pinna, then it is taken superiorly. The incision resembles a “reverse question-mark” shape. ◦ Ending point: It ends 1-2 cm lateral to the midline, behind the hairline. ◦ In case of scalp lacerations, it is advisable to try to incorporate them into the incision. Seek for foreign bodies and excise contused skin edges in elliptical fashion. • Branch of the facial nerve to the frontalis muscle. • Branches of the superficial temporal artery. Fig. 31.1 Reverse question-mark skin incision. • Myofascial level ◦ Myofascial level is incised according to skin incision. • Muscles ◦ The periosteum and the temporal muscle are divided using monopolar electrocautery. ◦ Using periosteal elevator and monopolar electrocautery, the scalp flap is detached along with the temporal muscle and reflected (as a single unit) antero-inferiorly. • Branch of the facial nerve to the frontalis muscle • Burr holes ◦ I: The first burr hole is placed at the low temporal area (temporal squama), right above the zygomatic arch. ◦ II: The second burr hole is made at the keyhole. ◦ III: The third burr hole might be placed, as preferred, along the planned craniotomy route. • Craniotomy landmarks ◦ Anterior: Orbital rim. ◦ Lateral: Zygomatic arch. ◦ Medial: 1 cm from the midline, sagittal suture. ◦ Posterior: Lambdoid suture. • Parenchymal, pial vessels or dural sinuses injury when elevating depressed fractures. • Dural sinuses. • “Cruciate/stellate” or in a C-shaped fashion. • Brain cortex. • Parenchymal structures: Lateral aspect of frontal, temporal and parietal lobes. • Arachnoidal layer: Sylvian fissure. • Arteries: Middle cerebral artery. • Veins: Superficial Sylvian vein, superior and inferior anastomotic veins, cortical veins of the lateral surface. • Indications: Bilateral brain swelling. • Schematic representation in Fig. 31.8 • Full description in Chapter 14.
31.1 Indications
31.2 Unilateral Craniectomy
31.2.1 Patient Positioning
31.2.2 Skin Incision
Critical Structures
Abbreviations: E = ear; M = midline.
31.2.3 Soft Tissues Dissection (Fig. 31.2)
Critical Structures
31.2.4 Craniotomy/Craniectomy (Figs. 31.3, 31.4)
Critical Structures
31.2.5 Dural Opening (Figs. 31.5, 31.6)
Critical Structures
31.2.6 Intradural Exposure (Fig. 31.7)
31.3 Variants
31.3.1 Bilateral Frontal Craniectomy
Neupsy Key
Fastest Neuropsychology Insight Engine
