Fronto-orbital advancement and reconstruction using reverse frontal bone graft without the use of orbital bar: a technical note

Child's Nervous System https://doi.org/10.1007/s00381-020-04583-w TECHNICAL NOTES Fronto-orbital advancement and reconstruction using reverse frontal bone graft without the use of orbital bar: a technical note James M. W. Robins 1 & Asim J. Sheikh 1 & Dmitri Shastin 1 & Moritz W. J. Schramm 1 & Paula Carter 1 & John L. Russell 2 & Mark Liddington 3 & Paul D. Chumas 1 Received: 1 September 2019 / Accepted: 19 March 2020 # The Author(s) 2020 Abstract Introduction We describe our technique of using reverse frontal bone graft for FOAR for patients with metopic or coronal synostosis and present our complications using the Leeds classification system for complications in craniosynostosis surgery. Methods Since April 2015, seventeen patients have been operated using this technique. We perform a frontal bone graft that is then reversed, and supraorbital margins are drilled out. The orbital bar is then removed and drilled down to make bone dust and on-lay bone grafts which are then used to fill gaps on exposed dura and fill in around the temporal region. Results All 17 patients who underwent this technique have good cosmetic results. We report 5 (29%) complications and 8 (47%) blood transfusions (7 exposures, 1 cell salvage). Keywords Craniofacial . Synostosis . Metopic . Coronal Introduction Coronal and metopic synostosis pose a specific challenge for surgical treatment having evolved from simple suturectomy to fronto-orbital advancement and reconstruction (FOAR) [1, 2]. Multiple FOAR techniques are described using templates for frontal bone graft [2], wire fixation or rigid metallic fixation or the use of resorbable plates. Orbital bar modifications include leaving intact, advancing the bar forward or, as demonstrated here, removing it altogether [3]. Remodelling techniques for metopic correction are recently described including the shell technique [4], cathedral dome procedure [5] and Lille’s frontal reshaping and rotation of the superior and lateral orbital rim [6]. * James M. W. Robins Paul D. Chumas 1 Department of Neurosurgery, Leeds General Infirmary, G Floor, Jubilee Building, Leeds LS1 3EX, UK 2 Department of Maxillofacial Surgery, Leeds General Infirmary, Great George St, Leeds LS1 3EX, UK 3 Department of Plastic and Reconstructive Surgery, Leeds General Infirmary, Great George St, Leeds LS1 3EX, UK Absorbable plates offer an alternative to rigid fixation but carry higher complications [7, 8]. A recent technique of orbital buttress offers an alternative to screws and plates altogether [9]. None of these techniques however addresses the problem of thinning in the bitemporal regions. Our technique for FOAR has evolved over the years from the standard Marchac template technique, to thinning down the inner table of the orbital bar so as to be able to better reshape it [10], through to our present procedure—where the orbital bar is removed but only used for bone dust and on lay grafts. The bone dust and grafts are used to fill the temporal area to avoid future thinning and to fill gaps at exposed dura. This aids bony fusion and provides a favourable cosmetic outcome. We describe the technique, outcomes and complications of this method in a single institution. Methods Patient selection All paediatric patients presenting with non-syndromic metopic or coronal synostosis since April 2015 underwent this technique in a single institution. Childs Nerv Syst Surgical technique anterior fossa floor being as close to the orbital rim as possible (Fig. 1b, c). Positioning, preparation and incision Patients are supine with head on horseshoe rest. Pressure areas are protected and the corneas covered with chloramphenicol antibiotic cream. The skin is prepared with aqueous iodinebased solution. A zigzag bicoronal incision is fashioned [Leach 2004] and flaps dissected to expose orbital rims anteriorly (Fig. 1a). The pericranium is divided in the midline and taken down bilaterally with the temporalis muscle. Frontal flap marking and removal of orbital bar Frontal bone flap is marked and removed. The orbital bar is then removed using standard technique with the cuts along the Fig. 1 Exposure and marking a, bone flap and orbital bar marking b, markings for next cut c, new frontal graft in place d, frontal graft with barrel staved part e, bone dust from removed orbital bar used to cover exposed dura f, bone removed from orbital bar used to fill biparietal gaps g, immediate post-op appearances h Bone flap reversal Frontal bone flap is then reversed, and new orbital rims are marked and fashioned as shown. In metopic cases, the new construct is not advanced, but in coronal cases, it is advanced as far as the soft tissue envelope will allow, typically 1.5– 2.0 cm. As this advancement is symmetrical, in cases of unicoronal synostosis, the advancement does not appear as an “over advancement” as seen in other techniques but will be significantly more advanced on the affected side. The advancement is maintained by resorbable LactoSorb plates and lag screws placed in the temporal region bilaterally and absorbable sutures to nasion (Fig. 1d). a b c d e f g h Childs Nerv Syst Reconstruction Cosmetic outcomes The remaining bone strip is barrel staved to be placed in the gap (Fig. 1e). Bone fragments from removed orbital rim are sited temporally to prevent temporal thinning (Fig. 1f). Remaining orbital bar is drilled to bone dust and covers any remaining exposed dura (Fig. 1g). The pericranium is tacked together to help hold the construct in place. Layered wound closure is with absorbable sutures for galea and monofilament subcuticular for skin (Fig. 1h). All patients had pre- and postoperative photographs taken for comparison, and all had satisfactory cosmetic outcomes (Fig. 2). Two patients had subtle forehead recession and one patient has a slightly uneven vertex at follow-up; however, none required reoperation, and parental satisfaction was confirmed. Ophthalmological follow up did not demonstrate pulsating exophthalmos in any patients at this length of follow up. Whilst we used to obtain standard skull X-rays as baseline postoperatively, we have moved to specially protocolled low dose CT head with 3D reconstruction as routine in our institution, and this confirmed good radiological outcomes in all patients. Results Demographics Between April 2015 and March 2019, we performed this procedure in 17 non-syndromic patients (9 female, 8 male; age range, 12–33 months; mean age, 19.2 months). There were eight unicoronal and nine metopic synostosis. Follow-up ranged from 1 to 34 months (median 16.2 months) and length of stay ranged 2–7 days (mean 4 days). Fig. 2 Pre- (a–b) and post-op appearances at 18 (f–j) and 34 months (k–o) for unicoronal synostosis Radiological outcomes Blood loss and transfusion exposure Seven patients (41%) underwent eight blood transfusions from seven blood bags; of which, three were intraoperative (one cell salvage) and five postoperative (one pa (...truncated)