Over many years, different techniques have been developed to treat AP due to non-syndromic UCS, but the lack of quality level evidence supporting a technique’s superiority over another has resulted in practical discrepancies. The lack of both evidence-based medicine and agreement between surgeons are regarded as the major obstacles in decision making in UCS management [5].
AP surgical repair has gone from strip craniectomy to the classic open FOA through a great advancement due to the inconsistent results and the reported high rate of recurrence of the strip craniectomy technique [7].
Despite global indications and implementation, all open FOA techniques have some disadvantages. It requires a long ear-to-ear scalp incision, blood transfusion necessity due to significant blood loss amount, and a prolonged hospital stay [7]. Several complications were reported in literature following open FOA techniques such as intracranial bleeding and hematomas formation, wound infections, dural tears, and cerebrospinal fluid leaks [8, 9]. Residual asymmetries, deformity relapses, and contour irregularities are also not uncommon and have been demonstrated in several studies [8,9,10,11,12].
The goals for efficient craniosynostosis treatment are adequate intracranial volume, sufficient for normal brain expansion, and to reduce the cognitive sequelae and obtain a normal cranium shape [13]. From this background, we innovated the rotational overlapping flap (ROF) technique for the correction of non-syndromic AP and reported its complications and outcome. We believe that our new technique has several similar advantages to the standard FOA, compared to minimal invasive techniques, regarding the immediate correction of the skull deformity and providing an adequate volume for the expanding brain. However, the ROF has several advantages over FOA in terms of simplicity, duration of surgery, the need for blood transfusion and postoperative hospital stay. It also has the advantage that the postoperative remodeling helmet is not needed as in several minimal invasive corrective techniques.
As for the ideal timing of the surgical management of craniosynostosis, interfering before the age of 1 year is usually recommended [14]. Most surgeons operate on the patient as soon as possible [13]. Earlier surgical correction benefits from the thinner and softer bones which are easier to remodel and the rapidly growing brain, thus minimizing consequent skull deformities and facial compensatory changes induced by brain growth. In older children, the bones become harder to remodel and lose the ossification properties and bone grafting is usually required [15]. This time window is crucial in our technique to obtain the best cosmetic results as it involves the overlap of the relatively thin bony edges to compensate for the deficient bone size, instead of the more aggressive bone advancement techniques.
Prolonged surgical time and anesthesia exposure have been related to several complications in pediatric patients. Naumann and colleagues [16] demonstrated inverse relations between neurodevelopment in children with craniosynostosis and the amount of anesthesia exposure. They found an average decline in developmental test scores from 1.1 to 2.9 for every 30-min increase in anesthesia duration. They concluded that this decline in neurodevelopmental scores may be attributed to the exposure to anesthesia, unspecific surgery effects, or unmeasured variables that correlate with the duration of surgery.
The duration of surgery in our series ranged from 83 to 110 min with a mean time of 95.3 min. This duration was markedly shorter than the duration of surgery for open corrective procedures reported in the literature. Guzman and colleagues [17] reported a mean operative time of 210 min in their series, and a hospital stay of 4.5 days compared to 2 days in our study. Zakhary and colleagues [8] reported an average surgical time of 216.7 min. Hassanpour and colleagues [18] also reported an average anesthetic time of 397.72 min in their study and an average hospital stay of 7.84 days.
Management of intraoperative unavoidable blood loss presents the greatest anesthetic challenge for craniosynostosis surgical correction [19]. Significant blood loss can occur from the subgalial tissues, bony edges, and dural sinuses breeching. Postoperative ICU admission and elective postoperative ventilation can be considered with prolonged surgical duration and hemodynamic instability [19, 20]. No intraoperative complications were reported in our study, and no blood transfusion was needed in any of the patients due to minimal surgical blood loss. Postoperatively, no ICU admission was recorded in any of the study cases and the patients were admitted to the ward. No wound infections or CSF leakage was reported in the follow-up period. This is probably attributed to the simplicity of the procedure, short operative and anesthetic time, and early hospital discharge besides the small number of patients.
For postoperative evaluation, several methods have been proposed for the analysis of the results of different surgical correction procedures for craniosynostosis such as repeated CT scans and different classification and scorings systems [6]. In the present study, we used standardized photographs to evaluate postoperative results based on the preoperative deformities of AP. The advantage of this simple method in comparison to other suggested methods [21,22,23,24,25] is that photographs can be taken easily routinely in the follow-up clinics, and therefore, the data are readily available. Furthermore, it is not time-consuming and does not involve radiation exposure. This method was previously used by Hilling and colleagues [6] in their evaluation of the long-term aesthetic results of fronto-orbital correction for AP.
A theoretical disadvantage of using photographs is its exaggeration of revealing deformities compared with the given real-life three-dimensional impression [6]. Therefore, we added the subjective satisfactory cosmetic outcome reported by the parents of the patients to our outcome evaluation.
Follow-up Ct brain with 3D skull reconstruction was done only in the first 2 cases of the study after 3 months and 1 year postoperatively to confirm bone remodeling and the occurrence of bony fusion.
A very promising cosmetic outcome satisfaction was reported by the parents of the operated patients in the present study. Complete satisfaction was reported by the parents of 6 patients (85.7%) while the parents of 1 patient were partially satisfied (14.3%). Their partial satisfaction was due to the presence of post-operative epilepsy and not related to cosmetic outcomes. No dissatisfaction or the need for a re-do surgery was reported by any of the parents. Our results revealed that our surgical technique produced appreciable improvement in all the presenting features of AP. The forehead shape was the most obvious preoperative deformity; therefore, our technique was mainly directed towards its correction. This was achieved by the rotation of the frontal craniotomy flap to use the more symmetrical curved surface of the postero-medial part of the frontal bone to replace the deficient flattened frontal part creating the new forehead shape. Moreover, augmentation of the frontal bone was done by overlapping the edges of the craniotomy flap with the anterior frontal bone medially to equalize the exaggerated contralateral frontal bossing.
Despite that our technique does not include correction of any accompanying orbital dystopia, improvement in the orbital appearance and normalization of the horizontal orbital position were probably achieved by the release and correction of the frontal supraorbital region. This observation was also reported by Hilling and colleagues [6] without addressing orbital dystopia correction in their surgical correction technique. In addition, we believe that the augmentation of the supraorbital region by the intended overlapping of the frontal craniotomy flap anteriorly over the supraorbital bar added to the normalization of the orbital appearance and consequently to the cosmetic outcome.
Temporal depression is a common observation following open FOA techniques. Several causes have been attributed to this cosmetic complication such as temporalis muscle suspension and atrophy, superficial temporal fat pad atrophy, and inadequate correction and advancement [26, 27]. Different techniques to avoid this problem have been proposed, such as temporal muscle elevation with the scalp flap [28], advancement and re-suspension of the temporalis muscle [29, 30], and musculo-osseous advancement flap [31, 32]. However, these techniques have failed to prevent this characteristic complication [31,32,33]. Ak Oh and colleagues [34] suggested that the inferior coronal gap between the advanced frontal bone and the parietal bone is the main cause of this finding causing a lack of structural continuity and support for the advanced temporalis muscle. They assumed that ossification of the wide bony gap occurs efficiently before dural expansion is complete with a resultant bony depression. This is markedly obvious as the infantile temporalis muscle bulk is insufficient to hide the underlying depression [34].
In our study, temporal depression was not observed in any of the cases in the follow-up period. We believe that this was attributed to many factors. Our technique followed all the recommendations to ensure a healthy postoperative temporalis muscle to prevent its atrophy. A myocutaneous flap was done in all cases, and no advancement and re-suspension of the temporalis muscle were needed. Unlike the FOA techniques, the ROF technique prevented the development of a significant structural bony discontinuity with an adequate underlying bony support for the temporalis muscle. Moreover, our technique prevented the creation of the wide inferior coronal gap and its assumed role in the development of the postoperative temporal bony depression.
