Neurosurg Focus 31 (2):E4, 2011 Reconstruction of unicoronal plagiocephaly with a hypercorrection surgical technique JOHN M. MESA, M.D.,1 FRANK FANG, M.D.,1 KARIN M. MURASZKO, M.D.,2 AND STEVEN R. BUCHMAN, M.D.1 1Division of Plastic Surgery and 2Department of Neurosurgery, University of Michigan Hospitals, Ann Arbor, Michigan Object. Successful surgical repair of unicoronal plagiocephaly remains a challenge for craniofacial surgeons. Many of the surgical techniques directed at correcting the stigmata associated with this craniofacial deformity (for ex- ample, ipsilateral supraorbital rim elevation [vertical dystopia], ipsilateral temporal constriction, C-shaped deformity of the face, and so on) are not long lasting and often result in deficient correction and the need for secondary revision surgery. The authors posit that the cause of this relapse was intrinsic deficiencies of the current surgical techniques. The aim of this study was to determine if correction of unilateral coronal plagiocephaly with a novel hypercorrection surgical technique could prevent the relapse of the characteristics associated with unicoronal plagiocephaly. Methods. The authors performed a retrospective analysis of 40 consecutive patients who underwent surgical repair of unicoronal plagiocephaly at their institution between 1999 and 2009. In all cases, the senior author (S.R.B.) used a hypercorrection technique for surgical reconstruction. Hypercorrection consisted of significant overcorrec- tion of the affected ipsilateral frontal and anterior temporal areas in the sagittal and coronal planes. Demographic, perioperative, and follow-up data were collected for comparison. The postsurgical appearance of the forehead was documented clinically and photographically and then evaluated and scored by 2 independent graders using the ex- panded Whitaker scoring system. A relapse was defined as a recurrence of preoperative features that required second- ary surgical correction. Results. The mean age of the patients at the time of the operation was 13 months (range 8–28 months). The mean follow-up duration was 57 months (range 3 months to 9.8 years). The postsurgical hypercorrection appearance per- sisted on average 6–8 months but gradually dissipated and normalized. No patients exhibited a relapse of unicoronal plagiocephalic characteristics that required surgical correction. In all cases the aesthetic results were excellent. Only 3 patients required reoperation for the management of persistent calvarial bone defects (2 cases) and removal of a symptomatic granuloma (1 case). Conclusions. Our study demonstrates that patients who undergo unicoronal plagiocephaly repair with a hyper- correction surgical technique avoid long-term relapse. Our results suggest that the surgical technique used in the cor- rection of unilateral coronal synostosis is strongly associated with the prevention of postsurgical relapse and that the use of this novel method decreases the need for surgical revision. (DOI: 10.3171/2011.6.FOCUS1193) KEY WORDS • craniosynostosis • unicoronal plagiocephaly • frontal plagiocephaly • temporal constriction • surgical relapse UCCESSFUL repair of all abnormal characteristics of secondary surgical procedure to correct postsurgical re- unicoronal plagiocephaly remains a challenge for sidual deformities, increasing the morbidity rate.23 craniofacial surgeons. Although the phenotypical Some resurgence of interest in endoscopic strip cra- Scharacteristics of unicoronal plagiocephaly have been niectomy repair of unilateral coronal synostosis has been clearly described (ipsilateral supraorbital rim elevation shown since the advent of adjuvant helmet therapy, but [vertical dystopia] and retrusion, ipsilateral frontal bone this technique is limited by the age limitations required retrusion, ipsilateral temporal constriction, contralateral for successful outcomes (< 3–5 months of age) and the frontal boss, contralateral temporal boss, and C-shaped variable degree of patient compliance with the manda- deformity of the face), current surgical techniques often tory postsurgical helmet protocols. The unreliable out- do not successfully achieve long-term correction of all comes have driven craniofacial surgeons to seek different of the associated deformities by a single surgical proce- surgical procedures.17,18 Currently, open approaches are dure.13,22,31 Multiple published reports have demonstrated considered the “standard of care” to correct unicoronal a sizeable subset of patients with unicoronal plagioceph- plagiocephaly. aly who undergo surgical correction and also require a Multiple open surgical techniques to correct unicoro- Neurosurg Focus / Volume 31 / August 2011 1 Unauthenticated | Downloaded 10/08/21 04:21 AM UTC J. M. Mesa et al. nal plagiocephaly have been described. Hoffman and ture synostosis, syndromic disease, and major concomitant Mohr13 have described the lateral canthal advancement medical conditions. technique for expanding the affected ipsilateral anterior cranial fossa by releasing the frontoethmoidal and fron- Surgical Technique tosphenoidal sutures that were also believed to contribute All surgical procedures were performed by the se- the characteristics of unicoronal plagiocephaly. Long- nior author (S.R.B.). A wavy bicoronal scalp incision was term follow-up of this technique has shown that 7 (17.9%) used. The anterior scalp flap was dissected in a subga- of 39 patients experienced relapse of the original defor- 22 leal plane and reflected anteriorly. Dissection transitioned mity warranting surgical reoperation. to the subpericranial plane 2 cm above the supraorbital One of the most common postsurgical deformities rims to avoid damaging the supraorbital neurovascular after unicoronal repair is ipsilateral temporal constric- 28,31 12 bundles. Dissection was extended to expose the nasofron- tion. Hilling et al. published an article on a series of tal junction, the anterior orbital aspect of the bilateral su- 53 patients who underwent unilateral coronal synostosis praorbital rim, and the bilateral frontozygomatic sutures. repair in which a bandeau advancement technique was Bilateral temporalis muscles were exposed by dissecting used. Patients in whom this technique was used, however, superficially to the deep temporal fascia. A frontal crani- commonly presented with residual postoperative tempo- 27 otomy was performed by the neurosurgeon in a standard ral constriction. Oh et al. showed that placement of cal- fashion.5 The supraorbital bar was harvested in a standard varia bone graft along the osteotomized coronal suture fashion without bandeau extensions.5 Bilateral temporalis could prevent temporal constriction. However, they did muscles flaps were dissected off the temporal fossa sub- not adequately substantiate their claims as they had an periosteally to a level inferior to the zygomatic arch. The insufficient number of patients to statistically support the supraorbital bar was contoured with Tessier bone benders reliability of the technique. Strikingly, Steinbacher and 31 to achieve a smooth flattened contour. The inferolateral colleagues demonstrated that all patients who underwent edge of the ipsilateral supraorbital rim was contoured unicoronal plagiocephaly repair in which a unilateral with rongeurs to achieve a widened and arched shape that frontoorbital advancement bandeau technique was used resembled the appearance of the contralateral unaffect- presented with residual postsurgical temporal hollowing. 9 ed side. Barrel stave osteotomies were performed in the Eppley et al. acknowledged that a significant number of ipsilateral temporal bone to widen the cranial vault and patients who underwent craniosynostosis repair required cross-strut stabilization was used to hold the correction hydroxyapatite-based cranioplasty to correct postsurgical out against the recoiling forces of the scalp.20 deformities (relapse). These reports affirm that a current The recontoured supraorbital bar is repositioned in single surgical procedure is unable to successfully and a hypercorrected position both in the coronal and sagit- predictably correct all the characteristics of coronal pla- tal planes. To achieve this hypercorrected position, the giocephaly. supraorbital bar was placed in a declined position (higher Surgical repair of unicoronal plagiocephaly requires on the unaffected side and lower on the affected side) in the correction of both the underlying bony deformity as- the coronal plane, with the unaffected side pivoting upon sociated with the synostotic suture as well as the manage- its frontozygomatic suture (Fig. 1 white arrow) and the ment of the overlying soft-tissue envelope. In line with the affected side positioned in a relatively inferior position tenets of the law of Wolff as well as the functional ma- upon the corresponding frontozygomatic suture (vertical trix theory, we believe that surgical techniques that repair hypercorrection) (Fig. 1 right arrow). The supraorbital unicoronal plagiocephaly without addressing the postsur- bar is also asymmetrically displaced anteriorly in the sag- gical recoil of the soft-tissue envelope may be associated 25,26,34 ittal plane so that the unaffected side keeps pivoting at its with a surgical relapse. We hypothesize that correc- corresponding frontozygomatic suture and the affected tion of unicoronal plagiocephaly with a hypercorrection side is positioned significantly anterior to its correspond- technique (one that overstretches the soft-tissue envelope ing frontozygomatic suture (horizontal