Syndrome of the Trephined: Quantitative Functional Improvement after Large Cranial Vault Reconstruction

Abstract

Background: Large decompressive craniectomies may be life-saving; however, they may also result in syndrome of the trephined. This postrecovery sequela is characterized by dizziness, fatigue, depression, weakness, speech slowing, gait disturbance, and impaired mentation. Because this entity is poorly understood, the authors attempted to quantify the functional improvement in patients with syndrome of the trephined after cranial vault reconstruction. Methods: Patients with cranial vault defects (>50 cm2) from trauma, meningioma, and hemorrhage were studied preoperatively and postoperatively (6 months) after cranial vault reconstruction using (1) the Cognistat Active Form and (2) the Functional Independence Measure instrument (n = 40). Cranial vault reconstructive techniques varied from split cranial bone to alloplastic implants (polyetheretherketone or titanium mesh). Results: Of the 143 patients treated with decompressive craniectomies, 28 percent (n = 40) developed symptoms of syndrome of the trephined. A larger craniectomy defect size correlated with development of syndrome of the trephined. Time from craniectomy to presentation of symptoms was 4.5 months. Time from craniectomy to cranial vault reconstruction was 6.1 months. Time from cranial vault reconstruction to symptom improvement was 4.3 days. Complete functional recovery of syndrome of the trephined was seen in 70 percent. Type of cranial vault reconstruction included polyetheretherketone implant (57.5 percent), split calvarial graft (22.5 percent), and titanium mesh (20 percent), and was not a determinant of functional improvement. Cognistat assessment score noted improvement (from 38 to 69); likewise, the Functional Independence Measure measurement tool showed improvement (from 38 to 98). Conclusions: Syndrome of the trephined occurs more frequently than previously described in posttraumatic patients with large cranial vault defects. Cranial vault reconstruction leads to significant, quantifiable functional improvement in a large number of patients. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.

Unrepaired decompressive craniectomy worsens motor performance in a rat traumatic brain injury model

“…www.nature.com/scientificreports/ performance recovery compared with those that underwent immediate cranioplasty following TBI. Both our current study and our human data demonstrate an association with unrepaired cranial defects and decreased motor performance 9 . Ex-vivo MRI demonstrated preserved cortical anatomy in the rats that underwent cranial repair following TBI which likely accounts for the improved motor performance when compared to TBI rats that underwent hemi-craniectomy.…”

“…These persistent deficits in the unrepaired rat calvarium (independent of TBI) mirror those seen in humans with SoT. In a recent publication by our group, 143 human subjects who underwent DC demonstrated a 28% incidence of SoT 9 . Of these 40 subjects with SoT, 70% demonstrated complete functional return on average 4.3 days following cranioplasty.…”

Syndrome of the Trephined: Clinical Spectrum, Risk Factors, and Impact of Cranioplasty on Neurological Recovery in a Prospective Cohort

“…Recent studies have shown an association between craniectomy size and SoT. [29,39] In a study by Tarr et al SoT incidence increased sharply when craniectomy area reached 50 cm 2 and beyond [39]. Although we did not nd a difference in mean craniectomy area between SoT and non-SoT group, the inclusion of only large craniectomies in our study (mean craniectomy area 112.8 ± 35.4 cm 2 ) limited the power to detect this association.…”

“…The main nding of this study is the high incidence of SoT in patients with large craniectomies, suggesting that the condition is underreported. [16,17,30,34,39] Contrary to previous studies we have identi ed that 65% patients suffered from SoT. A detailed prospective neurologic and radiologic assessment within four days before and after cranioplasty, allowed to identify the spectrum of SoT condition.…”

“…Syndrome of the Trephined (SoT) is an underrecognized complication after decompressive craniectomy (DC) with poorly determined incidence ranging between 1-40% in the literature. [16,17,29,30,34,39] SoT manifests by a delayed sensorimotor or cognitive worsening after craniectomy and is often associated with varying symptomatology, including headache, tinnitus, dizziness, fatigability, pain/discomfort at the site of craniectomy, feeling of apprehension, or depression. [2,15] The wide range of clinical manifestations and absence of well-de ned diagnostic criteria makes it a challenging diagnosis in clinical practice.…”