Conventional posterior cranial vault expansion: indications and results-review of the literature

Calvarial Vault Remodeling Technique for Lambdoid Craniosynostosis

SUMMARY

Premature fusion of the lambdoid suture is the most uncommon single-suture synostosis. It presents with a classic "windswept" appearance, a trapezoid-shaped head, and significant skull asymmetry notable for an ipsilateral mastoid bulge and contralateral frontal bossing. Because of the rarity of lambdoid synostosis, little is known about optimal techniques for its treatment. In particular, the proximity of the lambdoid suture to critical intracranial structures such as the superior sagittal and transverse sinuses represents a potential for significant intraoperative bleeding. Prior work has shown that parietal asymmetry persists after repair in these cases. In this article, the authors present a technique for the treatment of unilateral lambdoid craniosynostosis along with two representative cases. This calvarial vault remodeling technique requires the removal of both ipsilateral and contralateral parietal bones. These are moved across hemispheres and reinset on opposite sides to help correct the parietal asymmetry. Obliquely orientated barrel stave osteotomies are performed to provide a safe mechanism for correction of occipital flattening. The authors' early results show improvement in correction of volume asymmetry 1 year postoperatively relative to patients treated with prior calvarial vault remodeling techniques. The authors believe the technique presented here corrects the windswept appearance in patients with lambdoid craniosynostosis and also reduces the potential for complications. Further work will be necessary to confirm this technique's long-term efficacy in a larger cohort.

Morphometric analysis and outcomes following posterior cranial vault distraction in syndromic and multisuture craniosynostosis

BACKGROUND

Turribrachycephaly is a common feature in many syndromic and multisuture craniosynostoses and is traditionally treated with total cranial vault reshaping and fronto-orbital advancement. A staged approach with posterior cranial vault distraction as a primary procedure followed by anterior cranial vault reshaping has the advantage of reducing the vertical dimension of the skull in a controlled and gradual manner while expanding the cranial volume. The purpose of this study was to evaluate outcomes following posterior cranial vault expansion using distraction osteogenesis at a single tertiary pediatric center.

METHODS

This retrospective review included all cases of posterior cranial vault distraction at a single institution from 2008 to 2022 performed by one surgeon. Morphometric outcomes such as Turricephaly Index (TI) and posterior cranial volume (PCV) were assessed from pre- and postoperative computerized tomography scans for patients who underwent posterior cranial vault distraction as a primary first-stage operation. Clinical outcomes and complications were collated.

RESULTS

A total of 41 patients (25 females, 16 males; mean age 11 months) with syndromic craniosynostosis (n = 32) and nonsyndromic craniosynostosis (n = 9) were included. The main indication for posterior cranial vault distraction in this cohort was turricephaly (63%). The mean distraction distance was 25.9 mm and the mean decrease in TI was 18%. The estimated increase in PCV from distraction in this cohort was 19.7%. In this cohort of patients, 13 patients (32%) experienced complications but there were no mortalities.

CONCLUSION

Posterior cranial vault distraction osteogenesis is an effective surgical procedure to increase intracranial volume and correct turricephaly in children with syndromic and nonsyndromic craniosynostosis. This procedure is considered a safe and effective first-stage cranial operation in children with syndromic craniosynostosis with increased intracranial pressure and or turricephaly.

Chiari I malformation: management evolution and technical innovation

BACKGROUND AND DEFINITION

In recent years thanks to the growing use of radiological assessment, Chiari I malformation became one of the major diseases for a neurosurgeon to deal with. CIM can be classified according to the extent of cerebellar tonsil tip into the foramen magnum being a protrusion over five mm considered pathological. Such a disease is a heterogeneous condition with a multifactorial pathogenetic mechanism that can subdivided into a primary and secondary form. Regardless of the form, it seems that CIM is the result of an imbalance between the volume of the braincase and its content. Acquired CIMs are secondary to conditions causing intracranial hypertension or hypotension while the pathogenesis of primary forms is still controversial.

PATHOGENESIS AND TREATMENT

There are several theories in the literature but the most accepted one implies an overcrowding due to a small posterior cranial fossa. While asymptomatic CIM do not need treatment, symptomatic ones prompt for surgical management. Several techniques are proposed being the dilemma centered in the need for dural opening procedures and bony decompression ones.

CONCLUSION

Alongside the paper, the authors will address the novelty presented in the literature on management, diagnosis and pathogenesis in order to offer a better understanding of such a heterogeneous pathology.

Evaluation of Complications and Outcomes in Craniosynostosis by Age of Operation: Analysis of the National Surgical Quality Improvement Program-Pediatric

Considerable controversy exists around the optimal age on which to operate for craniosynostosis. This study aims to use data from the American College of Surgeons National Surgical Quality Improvement Program-Pediatric to assess the impact of operative age on hospital stay and outcomes. After excluding patients who underwent endoscopic cranial vault remodeling, a total of 3292 patients met inclusion criteria in the National Surgical Quality Improvement Program-Pediatric between 2012 and 2019. Median age at surgery was 300 days (interquartile range: 204-494). Patients between 0 and 6 months underwent the highest proportion of complex cranial vault remodeling, Current Procedural Terminology 61,558 ( n =44, 7.7%) and Current Procedural Terminology 61,559 ( n =317, 55.1%). White blood cell counts peaked in the 12 to 18 months group, and were lowest in the 24± months group. Hematocrit was lowest in the 0 to 6 months group and rose steadily to the 24± months group; the inverse pattern was found in platelet concentration, which was highest in the youngest patients and lowest in the oldest. Prothrombin time, international normalized ratio, and partial thromboplastin time were relatively consistent across all age groups. Younger patients had significantly shorter operating room times, which increased with patient age ( P <0.001). Younger patients also had significantly shorter length of stay ( P =0.009), though length of stay peaked between 12 and 18 months. There was a significantly lower rate of surgical site infection in younger patients, which occurred in 0.7% of patients 0 to 12 months and 1.0 to 3.0% in patients over 12 to 24± months. There was no significant difference in the average number of transfusions required in any age group ( P =0.961).