Comparing two fronto-orbital advancement strategies to treat trigonocephaly in metopic synostosis

Surgical strategy in treatment of metopic synostosis in a single centre experience: technical note and quantitative analysis of the outcomes

PURPOSE

Trigonocephaly is the most common craniosynostosis involving orbits. Although some degree of agreement has been reached regarding surgical timing and indications for treatment, there is no consensus regarding the ideal operative technique to guarantee an optimal morphological outcome. The purpose of this study is to describe both strategies and to compare morphological outcomes by means of morphological surface analysis obtained from three-dimensional (3D) stereophotogrammetry, with two different techniques.

METHODS

We retrospectively investigated 43 patients with metopic synostosis surgically treated between 2004 and 2020. Two different techniques were applied, addressed as technique A and B. Ten patients undergone postoperative 3d stereophotogrammetry were enrolled, and cephalometric measurements were taken and compared to a cohort of unaffected patients matched by age and gender.

RESULTS

Comparison of the groups demonstrated a hypercorrection of the metopic angle of the second technique, associated with a slightly lower correction of the interfrontoparietal diameter. The metopic angle showed to be significantly undercorrected with the first method.

CONCLUSIONS

Alternated barrel staving technique appears to be a quick and satisfactory method in cranial remodelling for metopic synostosis. It guarantees an optimal aesthetic result in the first years after surgery.

Piezosurgery in endoscopic-assisted trigonocephaly correction: a technical note

PURPOSE

This study aims to evaluate the effectiveness of the Piezosurgery® device in endoscopic-assisted correction of trigonocephaly. Trigonocephaly is a type of craniosynostosis characterized by a triangular-shaped forehead due to the premature fusion of the metopic suture. Traditional open cranial vault reconstruction, although common, is invasive and poses risks. The study explores a less invasive alternative using ultrasonic microvibrations for bone cutting, potentially reducing soft tissue damage and improving surgical outcomes.

METHODS

The Piezosurgery® device was employed in endoscopic trigonocephaly correction surgeries performed on patients under 4 months old at the French Referral Center for Craniosynostosis in Lyon. The technique involves making a small skin incision and performing osteotomies from the anterior fontanel to the glabella. A rigid 0° endoscope provides visibility, and the Piezosurgery® device enables precise bone cutting while preserving the dura mater. Post-surgery, patients were discharged within 3 days and required to wear a remodeling helmet for 6-8 months.

RESULTS

The use of Piezosurgery® device allowed precise osteotomies with minimal soft tissue damage. No dura mater injuries occurred in the patient series. The procedure was efficient, with an average duration of 80 min, and blood loss was minimal, reducing the need for blood transfusions. The endoscopic approach facilitated shorter surgical times and reduced postoperative infection risks. Enhanced visibility during surgery, due to cavitation effects, improved the accuracy of bone cuts. The technique demonstrated promising safety and esthetic outcomes, although it incurred higher costs compared to traditional methods.

CONCLUSION

Piezosurgery® device provides a safe and effective method for minimally invasive endoscopic correction of trigonocephaly. The device's ability to selectively cut bone while preserving soft tissues offers significant advantages, despite longer surgical times and higher costs. This technique represents a viable alternative to traditional open surgery, promoting better clinical outcomes and reduced recovery times.

Neoforehead Remodelling Techniques for Fronto-Orbital Advancement and Remodelling in the Oxford Craniofacial Unit: Lateral Remodelling and a Novel Central Self-Stabilizing S-Osteotomy Technique

Fronto-orbital advancement and remodelling (FOAR) has undergone many modifications over the years, aimed at improving outcomes and reducing risks for patients. This work describes 2 techniques for remodelling the neoforehead used by the Oxford Craniofacial Unit since 1995: lateral remodelling and a central S-Osteotomy. Both methods adopt bone from the vertex as a neoforehead, but they differ in their techniques to adapt its shape to that of the newly remodelled orbital bandeau. The novel S-Osteotomy technique can be successfully applied to all FOAR procedures, irrespective of underlying synostosis and calvarial symmetry. It was originally developed for when 2 separate bony panels were required to create a neoforehead in asymmetrical cases, but was adopted for single panel neoforehead designs in metopic synostosis with the idea it may reduce temporal hollowing. An investigation of temporal hollowing in these patients who underwent either of the described methods was undertaken to assess this hypothesis with no statistically significant difference seen ( P =0.1111). Both techniques on average resulted in minimal hollowing that was not felt to require any revision, supporting the belief that temporal hollowing is a multifactorial issue. This work describes 2 successful methods of neoforehead remodelling and introduces the S-Osteotomy technique that can be applied in all FOAR procedures.

Anthropometric cranial measurements in metopic craniosynostosis/trigonocephaly: diagnostic criteria, classification of severity and indications for surgery

ABSTRACT

Metopic craniosynostosis is the second most frequent type of craniosynostosis. When the phenotypic presentation has been deemed severe the treatment is surgical in nature and is performed in infancy with fronto-orbital advancement and cranial vault remodeling. At the time of this writing, there is no consensus regarding an objective evaluation system for severity, diagnostic criteria, or indications for surgery. This study aims to review the anthropometric cranial measurements and the relative diagnostic criteria/classification of severity/surgical indications proposed so far for this skull malformation, and to investigate if there is any scientific support for their utility.

Photogrammetric evaluation of corrective surgery for trigonocephaly

The aim of this study was to capture preoperative, postoperative, and follow-up head shapes of male trigonocephaly patients who underwent fronto-orbital remodelling (FOR), using three-dimensional (3D) photography. Fifty-seven male infants with metopic synostosis operated on using standardized FOR during a 5-year period were included. All measurements were compared with those of an age-matched healthy control cohort (n = 253 for early postoperative comparison, n = 43 for the 1-year follow-up comparison) to determine the effect of FOR at 14 days and at 1 year post-surgery. Intracranial volume, frontal angle, nasofrontal angle, interfrontoparietal-interparietal ratio, and inter-orbital distances were measured 1 day preoperatively, 14 days and 1 year postoperatively. Mean age at surgery was 9.7 ± 1.1 months. Prior to surgery, boys with metopic synostosis showed a reduced intracranial volume (-7.0%, P < 0.001), frontal angle (-10.2%, P < 0.001), interfrontoparietal-interparietal ratio (-4.9%, P < 0.01), and orbital distances (-6.5%, P < 0.001) compared to the reference group, but values did not differ significantly from the specific control group after surgery (all P> 0.05). This was consistent by the time of the follow-up examination. Corrective surgery should therefore aim to achieve volume expansion and correction of the deformity. Furthermore, 3D photogrammetry provides a valuable alternative to computed tomography scans in the diagnosis of metopic synostosis, significantly reducing the amount of radiation exposure to the brain.

Combating Constraints of the Functional Matrix: The Importance of Overcorrection in Pediatric Craniofacial Surgery

Background:

To effectively manipulate the bone, particularly in the growing patient, the craniofacial surgeon must understand the principles related to bone-based reconstruction. A theory of craniofacial growth that is both biologically accurate and clinically relevant is thus needed.

Methods:

A historical review of major findings across various disciplines (including orthopedic surgery, anatomy, embryology, orthodontics, and cell biology) will be covered, as it pertains to the concept of the functional matrix of the craniofacial skeleton.

Results:

The functional matrix dictates the interplay between the soft tissue envelope and bone grafts, thus guiding donor site choice and inset methods. The soft tissue may also warrant the use of bony hypercorrection especially in cranial vault remodeling. Control of both bone and boundaries of the soft tissue functional matrix can be achieved via distraction osteogenesis.

Conclusion:

The soft tissue functional matrix must be accounted for during craniofacial bone grafting, mobilizing osteotomies, and distraction osteogenesis if optimal aesthetic results are to be obtained using the least amount of procedures.

Comparison of Head Shape Outcomes in Metopic Synostosis Using Limited Strip Craniectomy and Open Vault Reconstruction Techniques

AIM

Metopic craniosynostosis (MCS), with its trigonocephalic head shape, is often treated with either limited incision strip craniectomy (LISC) followed by helmet orthotic treatment, or open cranial vault reconstruction techniques (OCVR). There is controversy regarding resultant shape outcomes among craniofacial surgeons. Those adverse to LISC claim normal head shape is never attained, while proponents believe there is gradual correction to an equivalent outcome. This study aims to quantitate, over time, the three-dimensional (3D) head shapes in patients who have undergone LISC or OCVR intervention for MCS.

METHODS

Sixty-three 3D images of 26 patients with MCS were analyzed retrospectively. Head shape analyses were performed at: (1) preoperative, (2) 1-month postoperative, (3) 10 to 14 months postoperative (1 year), and (4) 2 years postoperative. Composite 3D head shapes of patients were compared at each time point. Two-dimensional (2D) standardized cross sections of the forehead were also compared.

RESULTS

Composite head shapes for both groups were nested, to allow visual comparison as the child's forehead grows and expands. The difference between LISC and OCVR 2D cross sections was calculated; 108.26 mm preoperatively, 127.18 mm after 1-month postoperative, 51.05 mm after 10 to 14 months postoperative, and 27.03 mm after 2 years postoperative.

CONCLUSIONS

This study found excellent head shape outcomes for both the LISC and OCVR techniques at 2 years of age. It also corroborates the slow and progressive improvement in head shape with the LISC technique. This study highlights the advantages of 3D photography for measurement of contour outcomes, utilizing both 2D vector and 3D whole head analytical techniques.

Age at Craniosynostosis Surgery and Its Impact on Ophthalmologic Diagnoses: A Single-Center Retrospective Review

BACKGROUND

Ocular abnormalities in craniosynostosis are a persistent concern for patients and providers, and some surgeons feel that early surgical intervention for synostosis alleviates the progression of ophthalmologic abnormalities. In contradistinction, the authors hypothesize that operating early will have no bearing on postoperative ophthalmologic outcomes.

METHODS

Single-suture craniosynostosis patients who underwent surgical correction between 1989 and 2015 were reviewed. Patients with multisuture craniosynostosis, syndromic diagnoses, no preoperative ophthalmology evaluation, and less than 2 years of follow-up were excluded. Logistic regression was used to determine odds of preoperative and postoperative ophthalmologic abnormalities by age, while controlling for patient-level covariates.

RESULTS

One hundred seventy-two patients met inclusion criteria. The median age at surgery was 10 months (interquartile range, 7 to 12.9 months). Increasing age at the time of surgery was associated with increased odds of preoperative ophthalmologic diagnoses (OR, 1.06; p = 0.037) but not postoperative diagnoses (OR, 1.00; p = 0.91). Increasing age at surgery was also not associated with increased odds of ophthalmologic diagnoses, regardless of timing (OR, 1.04; p = 0.08). Patients with coronal synostosis (OR, 3.94; p = 0.036) had significantly higher odds of preoperative ophthalmologic diagnoses. Patients with metopic (OR, 5.60; p < 0.001) and coronal (OR, 7.13; p < 0.001) synostosis had significantly higher odds of postoperative ophthalmologic diagnoses.

CONCLUSIONS

After reviewing an expansive cohort, associations of both overall and postoperative ophthalmologic diagnoses with age at surgery were not found. The authors' findings thus run counter to the theory that early surgical intervention lessens the likelihood of postoperative ophthalmologic diagnoses and improves ophthalmologic outcomes.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Risk, III.

Syndromic Craniosynostosis

Management strategies for syndromic craniosynostosis patients require multidisciplinary subspecialty teams to provide optimal care for complex reconstructive approaches. The most common craniosynostosis syndromes include Apert (FGFR2), Crouzon (FGFR2), Muenke (FGFR3), Pfeiffer (FGFR1 and FGFR2), and Saethre-Chotzen (TWIST). Bicoronal craniosynostosis (turribrachycephaly) is most commonly associated with syndromic craniosynostosis. Disease presentation varies from mild sutural involvement to severe pansynostoses, with a spectrum of extracraniofacial dysmorphic manifestations. Understanding the multifaceted syndromic presentations while appreciating the panoply of variable presentations is central to delivering necessary individualized care. Cranial vault remodeling aims to relieve restriction of cranial development and elevated intracranial pressure and restore normal morphology.

In Situ Hinge Technique for the Frontal Bandeau for the Correction of Metopic Craniosynostosis Reduces Operative Time

BACKGROUND AND PURPOSE

Treatment of metopic craniosynostosis often involves bitemporal expansion of the anterior cranium. This report compares perioperative variables of a surgical technique in which the fronto-orbital bandeau is bent in situ to traditional fronto-orbital advancement and remodeling (FOAR).

METHOD/DESCRIPTION

Six patients undergoing the hinge technique were compared to the senior author's 6 most recent conventional FOARs. Study and control cohorts were reasonably well matched for age and sex; only those with nonsyndromic, single-suture metopic synostosis were included. Perioperative variables such as OR time, blood loss, hardware costs, length of stay, and perioperative complications were compared between groups using unpaired t tests.

RESULTS

Operative time was significantly decreased when the hinge technique was utilized, with a mean operative time of 159 ± 14.0 minutes for hinge patients and 193 ± 33.8 minutes for nonhinge patients (P = 0.049). Hardware was also significantly decreased from an average of 2.2 ± 1.0 plates and 35 ± 13.8 screws in nonhinge patients to 1 plate and 20 screws in each hinge patient (P < 0.02), for an average hardware saving of $2990 per hinge surgery (P = 0.019). Estimated blood loss, length of stay, and perioperative complications were not significantly different between groups. All patients in both groups had Whitaker 1 outcomes in short-term follow-up.

CONCLUSIONS

The hinge technique for the treatment of metopic synostosis is associated with a statistically significant decrease in operative time, hardware utilization, and hardware cost. Perioperative outcomes were similar between the hinge technique and traditional FOAR in the short term, and additional follow-up is needed to determine whether the 2 have similar long-term outcomes.

Debunking a Surgical Myth: Do Not Touch the Temporalis

BACKGROUND

A longstanding dictum exists to avoid surgical manipulation of the temporalis muscle out of concern for an exceedingly high rate of muscle atrophy and recurrent temporal hollowing. The authors challenge this surgical myth, considering such advice to be erroneous. The authors hypothesize that elevation of the temporalis muscle, if performed using standard muscle flap principles, will demonstrate excellent results.

METHODS

To assess temporalis response to surgical manipulation, the authors reviewed patients who underwent calvarial vault remodeling by the senior author for craniosynostosis between 1988 and 2011. Nonsyndromic patients with single-suture synostosis and 5 years of follow-up were eligible for inclusion. The medical record was used to measure rates of reoperation, recurrent temporal hollowing, and persistent temporalis overcorrection.

RESULTS

Of the cohort reviewed, 196 patients met inclusion criteria. Ten patients (5.1%) exhibited recurrent bitemporal constriction. One patient (0.5%) underwent a revision temporalis turnover flap, and 2 patients (1.0%) underwent soft tissue augmentation. The overall reoperation rate was 1.5%. Temporalis overcorrection, in an attempt to prophylactically rectify the expected atrophy after temporalis manipulation, persisted in 11 patients (5.6%). Three of these patients required treatment with steroid injections, Botox injections, or operative muscle debulking. The overall reoperation rate for temporalis overcorrection was 1.5%.

CONCLUSIONS

The authors' low reoperation rates for recurrent deformity, in combination with persistent temporalis overcorrection in 5.6% of patients, should dispel the myth that manipulation of the temporalis invariably results in atrophy. The muscle may be surgically manipulated, as long as plastic surgery principles are followed.

A new operative open-wings technique to correct the frontoforehead unit in metopic synostosis

The technology adoption and creation of a multidisciplinary team have helped to overcome the complexity associated. Craniofacial surgery has thus emerged from the valuable contributions of neurosurgery, maxillofacial surgery, plastic surgery, eyes, nose, and throat as well as head and neck surgery. A patient with trigonocephaly may present a prominent "keel" forehead, accompanied by recession of the lateral orbit rims, hypotelorism, and constriction of the anterior frontal fossa when the metopic suture fuses before 6 months of age. In a period between 2007 and 2011, in the Salesi Children's Hospital, were treated for nonsyndromic variety of metopic synostosis 11 infants; their ages ranged from 6 months to 9 months, and 7 were males and 4 females. The most important aims of our new surgical technique are the achievement of symmetry as well as normal proportion and reconstruction of the frontoforehead unit but remaining in a very conservative treatment. The morphology and position of the supraorbital ridge-lateral orbital rim region are key elements of upper facial esthetics. This new "open-wings" technique for the reconfiguration of the bilateral emisupraorbital bar requires a midline incomplete osteotomy that involves only the internal cortex of the frontonasal region. Hence, both lateral orbital walls are bent inwardly and tilting forward, as in computed tomographic scan planning, with a greenstick fracture pivoting on the preserved medial frontonasal region. This open-wings conservative technique allows the avoidance of the most important complication that may result in the traditional way such as dead space in the anterior cranial fossa, infections, and blood loss but with an achievement of satisfactory craniofacial form and aesthetic result.