Trigonocephaly

File:Trigonocephaly.png

File:Single suture synostosis.png]]

Trigonocephaly can either occur in a syndrome or isolated, all by itself. Trigonocephaly is associated with the following syndromes: Bohring-Opitz syndrome, Muenke syndrome, Jacobsen syndrome, Baller–Gerold syndrome and Say–Meyer syndrome. The etiology of trigonocephaly is mostly unknown although there are three main theories. Trigonocephaly is probably a multifactorial congenital condition, but due to limited proof of these theories this cannot safely be concluded.

The first theory assumes that the origin of pathological synostosis lies within disturbed bone formation early on in the pregnancy. Causes can either be genetic{{cite journal|year =1997|last1 =Wilkie|first1 =AO|title =Craniosynostosis: Genes and mechanisms|volume =6|issue =10|pages =1647–56|journal =Human Molecular Genetics|doi =10.1093/hmg/6.10.1647|pmid =9300656|doi-access =free}}{{cite journal|year =2007|last1 =Wilkie|first1 =AO|last2 =Bochukova|first2 =EG|last3 =Hansen|first3 =RM|last4 =Taylor|first4 =IB|last5 =Rannan-Eliya|first5 =SV|last6 =Byren|first6 =JC|last7 =Wall|first7 =SA|last8 =Ramos|first8 =L|last9 =Venâncio|first9 =M|last10 =Hurst|first10 =Jane A.|last11 =O'Rourke|first11 =Anthony W.|last12 =Williams|first12 =Louise J.|last13 =Seller|first13 =Anneke|last14 =Lester|first14 =Tracy|title =Clinical dividends from the molecular genetic diagnosis of craniosynostosis|journal =American Journal of Medical Genetics Part A|volume =143A|issue =16|pages =1941–9|doi =10.1002/ajmg.a.31905|pmid =17621648|s2cid =35697095}}Frydman M, Kauschansky A, Elian E. Trigonocephaly; a new familiail syndrome. Am J Med Genet 1984: 18: 55-9.{{cite journal|pmid =6741996|year =1984|last1 =Frydman|first1 =M|last2 =Kauschansky|first2 =A|last3 =Elian|first3 =E|title =Trigonocephaly: A new familial syndrome|volume =18|issue =1|pages =55–9|doi =10.1002/ajmg.1320180109|journal =American Journal of Medical Genetics|last4 =Opitz|first4 =John M.}}{{cite journal|year =1990|last1 =Hennekam|first1 =RC|last2 =Van Den Boogaard|first2 =MJ|title =Autosomal dominant craniosynostosis of the sutura metopica|volume =38|issue =5|pages =374–7|journal =Clinical Genetics|pmid =2282717|doi =10.1111/j.1399-0004.1990.tb03598.x|s2cid =27026160}} (9p22–24, 11q23, 22q11, FGFR1 mutation),{{cite journal|pmid =11173846|year =2000|last1 =Kress|first1 =W|last2 =Petersen|first2 =B|last3 =Collmann|first3 =H|last4 =Grimm|first4 =T|title =An unusual FGFR1 mutation (fibroblast growth factor receptor 1 mutation) in a girl with non-syndromic trigonocephaly|volume =91|issue =1–4|pages =138–40|journal =Cytogenetics and Cell Genetics|doi =10.1159/000056834|s2cid =37239155}} metabolic{{cite journal|pmid =1113223|year =1975|last1 =Penfold|first1 =JL|last2 =Simpson|first2 =DA|title =Premature craniosynostosis-a complication of thyroid replacement therapy|volume =86|issue =3|pages =360–3|journal =The Journal of Pediatrics|doi =10.1016/S0022-3476(75)80963-2}} (TSH suppletion in hypothyroidism){{cite journal|pmid =209162|year =1978|last1 =Johnsonbaugh|first1 =RE|last2 =Bryan|first2 =RN|last3 =Hierlwimmer|first3 =R|last4 =Georges|first4 =LP|title =Premature craniosynostosis: A common complication of juvenile thyrotoxicosis|volume =93|issue =2|pages =188–91|journal =The Journal of Pediatrics|doi =10.1016/S0022-3476(78)80493-4}}{{cite journal|pmid =17666613|year =2007|last1 =Rasmussen|first1 =SA|last2 =Yazdy|first2 =MM|last3 =Carmichael|first3 =SL|last4 =Jamieson|first4 =DJ|last5 =Canfield|first5 =MA|last6 =Honein|first6 =MA|title =Maternal thyroid disease as a risk factor for craniosynostosis|volume =110|issue =2 Pt 1|pages =369–77|doi =10.1097/01.AOG.0000270157.88896.76|journal =Obstetrics and Gynecology|s2cid =28956479|url =https://zenodo.org/record/1234838}} or pharmaceutical{{cite journal|pmid =9450889|year =1998|last1 =Lajeunie|first1 =E|last2 =Le Merrer|first2 =M|last3 =Marchac|first3 =D|last4 =Renier|first4 =D|title =Syndromal and nonsyndromal primary trigonocephaly: Analysis of a series of 237 patients|volume =75|issue =2|pages =211–5|doi =10.1002/(SICI)1096-8628(19980113)75:2<211::AID-AJMG19>3.0.CO;2-S|journal =American Journal of Medical Genetics}} (valproate in epilepsy).{{cite journal|pmid =18264949|year =2008|last1 =Valentin|first1 =M|last2 =Ducarme|first2 =G|last3 =Yver|first3 =C|last4 =Vuillard|first4 =E|last5 =Belarbi|first5 =N|last6 =Renier|first6 =D|last7 =Luton|first7 =D|title =Trigonocephaly and valproate: A case report and review of literature|volume =28|issue =3|pages =259–61|doi =10.1002/pd.1948|journal =Prenatal Diagnosis|s2cid =206345527}}{{cite journal|year =1988|last1 =Ardinger|first1 =HH|last2 =Atkin|first2 =JF|last3 =Blackston|first3 =RD|last4 =Elsas|first4 =LJ|last5 =Clarren|first5 =SK|last6 =Livingstone|first6 =S|last7 =Flannery|first7 =DB|last8 =Pellock|first8 =JM|last9 =Harrod|first9 =MJ|last10 =Lammer|first10 =Edward J.|last11 =Majewski|first11 =Frank|last12 =Schinzel|first12 =Albert|last13 =Toriello|first13 =Helga V.|last14 =Hanson|first14 =James W.|last15 =Optiz|first15 =John M.|last16 =Reynolds|first16 =James F.|title =Verification of the fetal valproate syndrome phenotype|journal =American Journal of Medical Genetics|volume =29|issue =1|pages =171–85|doi =10.1002/ajmg.1320290123|pmid =3125743}}

The second theory says that synostosis begins when the fetal head gets hindered in the pelvic outlet during birth.{{cite journal|pmid =7367110|year =1980|last1 =Graham Jr|first1 =JM|last2 =Smith|first2 =DW|title =Metopic craniostenosis as a consequence of fetal head constraint: Two interesting experiments of nature|volume =65|issue =5|pages =1000–2|journal =Pediatrics|doi =10.1542/peds.65.5.1000|s2cid =27668507}}{{cite journal|pmid =16217480|year =2005|last1 =Smartt Jr|first1 =JM|last2 =Karmacharya|first2 =J|last3 =Gannon|first3 =FH|last4 =Teixeira|first4 =C|last5 =Mansfield|first5 =K|last6 =Hunenko|first6 =O|last7 =Shapiro|first7 =IM|last8 =Kirschner|first8 =RE|title =Intrauterine fetal constraint induces chondrocyte apoptosis and premature ossification of the cranial base|volume =116|issue =5|pages =1363–9|journal =Plastic and Reconstructive Surgery|doi =10.1097/01.prs.0000182224.98761.cf|s2cid =23430674}}

The third theory predominates disturbed brain formation of the two frontal lobes as the main issue behind synostosis.{{cite journal|pmid =13441914|year =1957|last1 =Riemenschneider|first1 =PA|title =Trigonocephaly|volume =68|issue =6|pages =863–5|journal =Radiology| doi = 10.1148/68.6.863}}{{cite journal|pmid =14424622|year =1959|last1 =Moss|first1 =ML|title =The pathogenesis of premature cranial synostosis in man|volume =37|pages =351–70|journal =Acta Anatomica|doi =10.1159/000141479|issue =4}}{{cite journal|pmid =17186250|year =2007|last1 =Kapp-Simon|first1 =KA|last2 =Speltz|first2 =ML|last3 =Cunningham|first3 =ML|last4 =Patel|first4 =PK|last5 =Tomita|first5 =T|title =Neurodevelopment of children with single suture craniosynostosis: A review|volume =23|issue =3|pages =269–81|doi =10.1007/s00381-006-0251-z|journal =Child's Nervous System|s2cid =29722887}} Limited growth of the frontal lobes leads to an absence of stimuli for cranial growth, therefore causing premature fusion of the metopic suture.{{citation needed|date=October 2020}}

{{multiple image

| direction=vertical

| width=120

| image1=Microcephalics (inset, D).jpg

| alt1=male

| image2=Microcephalic idiot with local myxedema.jpg

| alt2=female

| footer=Trigonocephaly in two cases of microcephaly

}}

Other conditions and syndromes with trigonocephaly include:

• Arthrogryposis, cleft palate, craniosynostosis, and impaired intellectual development
• Atypical glycine encephalopathy
• Blepharophimosis-intellectual disability syndrome, Verloes type
• Bohring-Opitz syndrome
• Coffin-Siris syndrome
• Greig cephalopolysyndactyly syndrome
• Holoprosencephaly
• Mandibulofacial dysostosis-microcephaly syndrome
• MEGF8-related Carpenter syndrome
• Microcephaly, primary autosomal dominant
• Mucolipidosis type II
• Orofaciodigital syndrome type 14
• Paris-Trousseau thrombocytopenia
• Potocki-Lupski syndrome
• Simpson-Golabi-Behmel syndrome type 1
• Trichothiodystrophy, photosensitive
• Trigonocephaly-bifid nose-acral anomalies syndrome

Diagnosis can be characterized by typical facial and cranial deformities.{{cite journal|last1=Anderson|first1=Frank M|last2=Gwinn|first2=John L|last3=Todt|first3=John C|date=September 1962|title=Trigonocephaly. Identity and surgical treatment|journal=Journal of Neurosurgery|volume=19|issue=9|pages=723–30|doi=10.3171/jns.1962.19.9.0723|pmid=13861226|doi-access=free}}

Observatory signs of trigonocephaly are:

• a triangular forehead seen from top view leading to a smaller anterior cranial fossa
• a visible and palpable midline ridge
• hypotelorism inducing ethmoidal hypoplasia

Imaging techniques (3D-CT, röntgenography, MRI) show:

• epicanthal folds in limited cases
• teardrop-shaped orbits angulated towards the midline of the forehead ('surprised coon' sign) in severe cases
• a contrast difference between a röntgenograph of a normal and a trigonocephalic skull
• anterior curving of the metopic suture seen from lateral view of the cranium on a röntgenograph
• a normal cephalic index (maximum cranium width / maximum cranium length) however, there is bitemporal shortening and biparietal broadening

The neuropsychological development is not always affected. These effects are only visible in a small percentage of children with trigonocephaly or other suture synostoses.

Neuropsychological signs are:

• problems in behaviour, speech and language
• mental retardation{{cite journal|pmid =5643989|year =1968|last1 =Shillito Jr|first1 =J|last2 =Matson|first2 =DD|title =Craniosynostosis: A review of 519 surgical patients|volume =41|issue =4|pages =829–53|journal =Pediatrics|doi =10.1542/peds.41.4.829|s2cid =2187741}}{{cite journal|pmid =7207779|year =1981|last1 =Anderson|first1 =FM|title =Treatment of coronal and metopic synostosis: 107 cases|volume =8|issue =2|pages =143–9|journal =Neurosurgery|doi =10.1227/00006123-198102000-00001}}
• neurodevelopmental delays such as attention deficit hyperactivity disorder (ADHD), oppositional defiant disorder (ODD), autism spectrum disorder (ASD), and conduct disorder (CD).{{cite journal|year = 1996|last1 = Collmann|first1 = H|last2 = Sörensen|first2 = N|last3 = Krauss|first3 = J|title = Consensus: Trigonocephaly|journal = Child's Nervous System|volume = 12|issue = 11|pages = 664–8|doi = 10.1007/BF00366148|pmid = 9118128|s2cid = 32346174}}{{cite journal|pmid =15714353|year =2005|last1 =Aryan|first1 =HE|last2 =Jandial|first2 =R|last3 =Ozgur|first3 =BM|last4 =Hughes|first4 =SA|last5 =Meltzer|first5 =HS|last6 =Park|first6 =MS|last7 =Levy|first7 =ML|title =Surgical correction of metopic synostosis|volume =21|issue =5|pages =392–8|doi =10.1007/s00381-004-1108-y|journal =Child's Nervous System|s2cid =22517024}}{{cite journal|year =1987|last1 =Oi|first1 =S|last2 =Matsumoto|first2 =S|title =Trigonocephaly (metopic synostosis). Clinical, surgical and anatomical concepts|journal =Child's Nervous System|volume =3|issue =5|pages =259–65|doi =10.1007/BF00271819|pmid =3427566|s2cid =11548878}}{{cite journal|pmid =8559809|year =1996|last1 =Sidoti Jr|first1 =EJ|last2 =Marsh|first2 =JL|last3 =Marty-Grames|first3 =L|last4 =Noetzel|first4 =MJ|title =Long-term studies of metopic synostosis: Frequency of cognitive impairment and behavioral disturbances|volume =97|issue =2|pages =276–81|journal =Plastic and Reconstructive Surgery|doi =10.1097/00006534-199602000-00002|s2cid =24545701}} Many of these delays become evident at school age.{{cite journal|pmid =9603552|year =1998|last1 =Kapp-Simon|first1 =KA|title =Mental development and learning disorders in children with single suture craniosynostosis|volume =35|issue =3|pages =197–203|journal = The Cleft Palate-Craniofacial Journal|doi =10.1597/1545-1569(1998)035<0197:MDALDI>2.3.CO;2}}

Treatment is surgical with attention to form and volume. Surgery usually takes place before the age of one since it has been reported that the intellectual outcome is better.{{cite journal|pmid =8081607|year =1994|last1 =Marchac|first1 =D|last2 =Renier|first2 =D|last3 =Broumand|first3 =S|title =Timing of treatment for craniosynostosis and facio-craniosynostosis: A 20-year experience|volume =47|issue =4|pages =211–22|journal =British Journal of Plastic Surgery|doi =10.1016/0007-1226(94)90001-9|doi-access =free}}{{cite journal|pmid = 6709733|year = 1984|last1 = McCarthy|first1 = JG|last2 = Epstein|first2 = F|last3 = Sadove|first3 = M|last4 = Grayson|first4 = B|last5 = Zide|first5 = B|title = Early surgery for craniofacial synostosis: An 8-year experience|volume = 73|issue = 4|pages = 521–33|journal = Plastic and Reconstructive Surgery|doi = 10.1097/00006534-198404000-00001|last6 = McCarthy|first6 = Joseph G.|s2cid = 19795497}}{{cite journal|year =2000|last1 =Renier|first1 =D|last2 =Lajeunie|first2 =E|last3 =Arnaud|first3 =E|last4 =Marchac|first4 =D|title =Management of craniosynostoses|journal =Child's Nervous System|volume =16|issue =10–11|pages =645–58|doi =10.1007/s003810000320|pmid =11151714|s2cid =22876385}}{{cite journal|pmid =3602170|year =1987|last1 =Whitaker|first1 =LA|last2 =Bartlett|first2 =SP|last3 =Schut|first3 =L|last4 =Bruce|first4 =D|title =Craniosynostosis: An analysis of the timing, treatment, and complications in 164 consecutive patients|volume =80|issue =2|pages =195–212|journal =Plastic and Reconstructive Surgery|doi =10.1097/00006534-198708000-00006}}{{citation overkill|date=October 2020}}

{{multiple image

| align =

| direction = horizontal

| width = 200

| footer =

| image1 = Wiki trigonocephaly1.jpg

| alt1 =

| caption1 = A. Fronto-supraorbital advancement and remodelling – before remodelling

| image2 = Wiki trigonocephaly2.jpg

| alt2 =

| caption2 = B. Fronto-supraorbital advancement and remodelling – after remodelling

}}

A form of surgery is the so-called fronto-supraorbital advancement and remodelling.{{cite journal|pmid =18216668|year =2008|last1 =Van Der Meulen|first1 =JJ|last2 =Nazir|first2 =PR|last3 =Mathijssen|first3 =IM|last4 =Van Adrichem|first4 =LN|last5 =Ongkosuwito|first5 =E|last6 =Stolk-Liefferink|first6 =SA|last7 =Vaandrager|first7 =MJ|title =Bitemporal depressions after cranioplasty for trigonocephaly: A long-term evaluation of (supra) orbital growth in 92 patients|volume =19|issue =1|pages =72–9|doi =10.1097/scs.0b013e31815c8a68|journal =The Journal of Craniofacial Surgery|s2cid =41247691}} Firstly, the supraorbital bar is remodelled by a wired greenstick fracture to straighten it. Secondly, the supraorbital bar is moved 2 cm. forward and fixed only to the frontal process of the zygoma without fixation to the cranium. Lastly, the frontal bone is divided into two, rotated and attached to the supraorbital bar causing a nude area (craniectomy) between the parietal bone and frontal bone. Bone will eventually regenerate since the dura mater lies underneath (the dura mater has osteogenic capabilities). This results in an advancement and straightening of the forehead.

The so-called 'floating forehead technique' combined with the remodelling of the supraorbital bar is derived from the fronto-supraorbital advancement and remodelling. The supraorbital bar is remodelled as described above.{{cite journal|last=Marchac|first=D|title=Radical forehead remodeling for craniostenosis.|journal=Plastic and Reconstructive Surgery|date=June 1978|volume=61|issue=6|pages=823–35|pmid=662945|doi=10.1097/00006534-197861060-00001}}{{cite journal|pmid =11109361|year =2000|last1 =Meling|first1 =TR|last2 =Due-Tønnessen|first2 =BJ|last3 =Helseth|first3 =E|title =Metotopic craniosynostoses|volume =120|issue =26|pages =3147–50|journal =Tidsskrift for den Norske Laegeforening}} The frontal bone is split in two pieces. Instead of using both pieces as in fronto-supraorbital advancement and remodelling, only one piece is rotated and attached to the supraorbital bar. This technique also leaves a craniectomy behind.{{cite journal|pmid =3345401|year =1988|last1 =Marchac|first1 =D|last2 =Renier|first2 =D|last3 =Jones|first3 =BM|title =Experience with the "floating forehead"|volume =41|issue =1|pages =1–15|journal =British Journal of Plastic Surgery|doi =10.1016/0007-1226(88)90137-3|doi-access =free}}

• Suturectomy

{{quote|The simplest form of surgery for trigonocephaly was suturectomy.{{cite journal|pmid =956873|year =1976|last1 =Hoffman|first1 =HJ|last2 =Mohr|first2 =G|title =Lateral canthal advancement of the supraorbital margin. A new corrective technique in the treatment of coronal synostosis|volume =45|issue =4|pages =376–81|doi =10.3171/jns.1976.45.4.0376|journal =Journal of Neurosurgery}}{{cite journal|pmid =3748350|year =1986|last1 =Delashaw|first1 =JB|last2 =Persing|first2 =JA|last3 =Park|first3 =TS|last4 =Jane|first4 =JA|title =Surgical approaches for the correction of metopic synostosis|volume =19|issue =2|pages =228–34|journal =Neurosurgery|doi =10.1227/00006123-198608000-00008}} However, as this technique was insufficient to correct the deformities, it is not used anymore.}}

• Distraction osteogenesis

{{quote|Distraction osteogenesis is based on creating more cranial space for the brain by gradually moving the bones apart. This can be achieved by using springs.{{cite journal|pmid =16902340|year =2006|last1 =Akai|first1 =Takuya|last2 =Iizuka|first2 =Hideaki|last3 =Kawakami|first3 =Shigehiko|title =Treatment of craniosynostosis by distraction osteogenesis|volume =42|issue =5|pages =288–92|doi =10.1159/000094064|journal =Pediatric Neurosurgery|s2cid =31884062}}}}

• Minimal invasive endoscopic surgery

These approaches are 2D solutions for a 3D problem, therefore the results are not optimal. Distraction osteogenesis and minimal invasive endoscopic surgery are yet in experimental phase.

Trigonocephaly seems to be the most compliant form of craniosynostosis for surgery. Because of standardization of current surgical approaches there is no surgical mortality and complications are few to none.{{cite journal|year =1996|last1 =Di Rocco|first1 =C|last2 =Velardi|first2 =F|last3 =Ferrario|first3 =A|last4 =Marchese|first4 =E|title =Metopic synostosis: In favour of a "simplified" surgical treatment|journal =Child's Nervous System|volume =12|issue =11|pages =654–63|doi =10.1007/BF00366147|pmid =9118127|s2cid =12026358}}Galassi E, Giulioni M, Acciarri N, Cavina C, Pistorale T. Marchac procedure in the early treatment of metopic and coronal synostoses. Presented at the Consensus Conference on Craniosynostoses, Rome 1995.

The simple suturectomy is presently insufficient to adjust the complicated growth restrictions caused by metopic synostosis. On the other hand, the fronto-supraorbital advancement and remodelling and the 'floating forehead technique' create sufficient space for brain growth and result in a normal horizontal axis of the orbits and supraorbital bar. The fronto-supraorbital advancement and remodelling is the most used method nowadays.

Over the past few years{{When|date=January 2020}} distraction osteogenesis has been gradually acknowledged since it has a positive effect on hypotelorism.{{Citation needed|date=January 2020}} Expanding the distance between the orbits using springs seems to be successful.{{cite journal|pmid =18300975|year =2008|last1 =Lauritzen|first1 =CG|last2 =Davis|first2 =C|last3 =Ivarsson|first3 =A|last4 =Sanger|first4 =C|last5 =Hewitt|first5 =TD|title =The evolving role of springs in craniofacial surgery: The first 100 clinical cases|volume =121|issue =2|pages =545–54|doi =10.1097/01.prs.0000297638.76602.de|journal =Plastic and Reconstructive Surgery|s2cid =24667119}}{{cite journal|pmid =17312504|year =2007|last1 =Maltese|first1 =G|last2 =Tarnow|first2 =P|last3 =Lauritzen|first3 =CG|title =Spring-assisted correction of hypotelorism in metopic synostosis|volume =119|issue =3|pages =977–84|doi =10.1097/01.prs.0000252276.46113.ee|journal =Plastic and Reconstructive Surgery|s2cid =42309644}}{{cite journal|pmid =19165007|year =2009|last1 =Davis|first1 =C|last2 =Lauritzen|first2 =CG|title =Frontobasal suture distraction corrects hypotelorism in metopic synostosis|volume =20|issue =1|pages =121–4|doi =10.1097/SCS.0b013e318190e25d|journal =The Journal of Craniofacial Surgery|s2cid =111447}} However, there are discussions whether hypotelorism really needs to be corrected.{{cite journal|pmid =8596780|year =1996|last1 =Fearon|first1 =JA|last2 =Kolar|first2 =JC|last3 =Munro|first3 =IR|title =Trigonocephaly-associated hypotelorism: Is treatment necessary?|volume =97|issue =3|pages =503–9; discussion 510–11|journal =Plastic and Reconstructive Surgery|doi =10.1097/00006534-199603000-00001|s2cid =19640552}}

The minimal invasive endoscopic surgery has been gaining attention since the early '90s, however, it has technical limitations (only strip craniectomy is possible). Attempts have been made to reach beyond these limits.{{cite journal|pmid =11149758|year =1999|last1 =Barone|first1 =CM|last2 =Jimenez|first2 =DF|title =Endoscopic craniectomy for early correction of craniosynostosis|volume =104|issue =7|pages =1965–73; discussion 1974–5|journal =Plastic and Reconstructive Surgery|doi =10.1097/00006534-199912000-00003}}{{cite journal|pmid =17489491|year =2007|last1 =Hinojosa|first1 =J|last2 =Esparza|first2 =J|last3 =García-Recuero|first3 =I|last4 =Romance|first4 =A|title =Endoscopically assisted fronto-orbitary correction in trigonocephaly|volume =20|issue =1|pages =33–8|journal =Cirugia Pediatrica }}{{cite journal|year =2005|last1 =Murad|first1 =GJ|last2 =Clayman|first2 =M|last3 =Seagle|first3 =MB|last4 =White|first4 =S|last5 =Perkins|first5 =LA|last6 =Pincus|first6 =DW|title =Endoscopic-assisted repair of craniosynostosis|volume =19|issue =6|pages =E6|journal =Neurosurgical Focus|doi =10.3171/foc.2005.19.6.7|pmid =16398483|s2cid =18876090|doi-access =free}}{{cite journal|pmid =9420076|year =1998|last1 =Jimenez|first1 =DF|last2 =Barone|first2 =CM|title =Endoscopic craniectomy for early surgical correction of sagittal craniosynostosis|volume =88|issue =1|pages =77–81|doi =10.3171/jns.1998.88.1.0077|journal =Journal of Neurosurgery|s2cid =36281056}}{{cite journal|pmid =17899127|year =2007|last1 =Hinojosa|first1 =J|last2 =Esparza|first2 =J|last3 =Muñoz|first3 =MJ|title =Endoscopic-assisted osteotomies for the treatment of craniosynostosis|volume =23|issue =12|pages =1421–30|doi =10.1007/s00381-007-0473-8|journal =Child's Nervous System|s2cid =9318496}}

Aesthetic outcome of metopic synostosis surgery is persistently good with reoperation hazards below 20%.{{cite journal|year =2006|last1 =Greenberg|first1 =BM|last2 =Schneider|first2 =SJ|title =Trigonocephaly: Surgical considerations and long term evaluation|journal =The Journal of Craniofacial Surgery|volume =17|issue =3|pages =528–35|doi =10.1097/00001665-200605000-00024|pmid =16770193|s2cid =13150853}}{{cite journal|pmid =7972420|year =1994|last1 =Cohen|first1 =SR|last2 =Maher|first2 =H|last3 =Wagner|first3 =JD|last4 =Dauser|first4 =RC|last5 =Newman|first5 =MH|last6 =Muraszko|first6 =KM|title =Metopic synostosis: Evaluation of aesthetic results|volume =94|issue =6|pages =759–67|journal =Plastic Surgery|doi =10.1097/00006534-199411000-00002|s2cid =21873862}} In 1981 Anderson advised that craniofacial operations for synostosis should be as extensive as necessary after a study of 107 cases of metopic and coronal synostosis. Surgery does not provide a 100% natural outcome, mostly there will be minor irregularities. Reoperations are usually performed on more severe cases (including syndromic metopic synostosis). The hypotelorism and temporal hollowing are the most difficult to correct: the hypotelorism usually remains under corrected and a second operation is often needed for correction of temporal hollowing.{{cite journal|pmid =8278471|year =1994|last1 =Posnick|first1 =JC|last2 =Lin|first2 =KY|last3 =Chen|first3 =P|last4 =Armstrong|first4 =D|title =Metopic synostosis: Quantitative assessment of presenting deformity and surgical results based on CT scans|volume =93|issue =1|pages =16–24|journal =Plastic and Reconstructive Surgery|doi =10.1097/00006534-199401000-00003}}

The highest rate of neurological problems of single suture synostosis are seen in patients with trigonocephaly. Surgery is performed generally before the age of one because of claims of better intellectual outcome. Seemingly surgery does not influence the high incidence of neurodevelopment problems in patients with metopic synostosis. Neurological disorders such as ADHD, ASD, ODD and CD are seen in patients with trigonocephaly. These disorders are usually also associated with decreased IQ. The presence of ADHD, ASD and ODD is higher in cases with an IQ below 85. This is not the case with CD which showed an insignificant increase at an IQ below 85.

The incidence of metopic synostosis is roughly between 1:700 and 1:15,000 newborns globally (differs per country).{{cite journal|year =1997|last1 =Alderman|first1 =BW|last2 =Fernbach|first2 =SK|last3 =Greene|first3 =C|last4 =Mangione|first4 =EJ|last5 =Ferguson|first5 =SW|title =Diagnostic practice and the estimated prevalence of craniosynostosis in Colorado|volume =151|issue =2|pages =159–64|journal =Archives of Pediatrics & Adolescent Medicine|doi =10.1001/archpedi.1997.02170390049009|pmid =9041871}} Trigonocephaly is seen more in males than females ranging from 2:1 to 6.5:1.{{cite journal|pmid =2253382|year =1990|last1 =Friede|first1 =H|last2 =Alberius|first2 =P|last3 =Lilja|first3 =J|last4 =Lauritzen|first4 =C|title =Trigonocephaly: Clinical and cephalometric assessment of craniofacial morphology in operated and nontreated patients|volume =27|issue =4|pages =362–7; discussion 368|journal = The Cleft Palate-Craniofacial Journal|doi =10.1597/1545-1569(1990)027<0362:TCACAO>2.3.CO;2|s2cid =39803020}}{{cite journal|pmid =1822130|year =1991|last1 =Genitori|first1 =L|last2 =Cavalheiro|first2 =S|last3 =Lena|first3 =G|last4 =Dollo|first4 =C|last5 =Choux|first5 =M|title =Skull base in trigonocephaly|volume =17|issue =4|pages =175–81|journal =Pediatric Neurosurgery|doi =10.1159/000120591}}{{cite journal|pmid =2601658|year =1989|last1 =Dirocco|first1 =C|last2 =Caldarelli|first2 =M|last3 =Ceddia|first3 =A|last4 =Iannelli|first4 =A|last5 =Velardi|first5 =F|title =Craniostenosis. Analysis of 161 cases surgically treated during the first year of life|volume =41|issue =8|pages =393–404|journal =Minerva Pediatrica}}{{cite journal|pmid =3791279|year =1986|last1 =Dhellemmes|first1 =P|last2 =Pellerin|first2 =P|last3 =Lejeune|first3 =JP|last4 =Lepoutre|first4 =F|title =Surgical treatment of trigonocephaly. Experience with 30 cases|volume =2|issue =5|pages =228–32|journal =Child's Nervous System|doi=10.1007/BF00272491|s2cid =44728949}} Hereditary relations in metopic synostosis have been found of which 5.5% were well defined syndromic. Maternal age and a birth weight of less than 2500g may also play a role in trigonocephaly.{{cite journal|pmid =18344207|year =2008|last1 =Boulet|first1 =SL|last2 =Rasmussen|first2 =SA|last3 =Honein|first3 =MA|title =A population-based study of craniosynostosis in metropolitan Atlanta, 1989-2003|volume =146A|issue =8|pages =984–91|doi =10.1002/ajmg.a.32208|journal =American Journal of Medical Genetics Part A|s2cid =33500062}} These data are based on estimations and do not give factual information.

Only one article gives valuable and reliable information regarding the incidence of metopic synostosis in the Netherlands. The incidence in the Netherlands showed an increase from 0.6 (1997) to 1.9 (2007) for every 10,000 live births.{{cite journal|pmid =20888312|year =2010|last1 =Kweldam|first1 =CF|last2 =Van Der Vlugt|first2 =JJ|last3 =Van Der Meulen|first3 =JJ|title =The incidence of craniosynostosis in the Netherlands, 1997-2007|doi =10.1016/j.bjps.2010.08.026|journal =Journal of Plastic, Reconstructive & Aesthetic Surgery|volume =64|issue =5|pages =583–588}}

In former times people born with malformed skulls were rejected based upon their appearance.Strickler M, van der Meulen J, Rahael B, Mazolla R. Craniofacial malformations. Edinburgh, London, Melbourne, New York: Churchill Livingston, 1990.{{cite journal |pmid =6406099 |year =1983 |last1 =Vermeij-Keers |first1 =C |last2 =Mazzola |first2 =RF |last3 =Van Der Meulen |first3 =JC |last4 =Strickler |first4 =M |title =Cerebro-craniofacial and craniofacial malformations: An embryological analysis |volume =20 |issue =2 |pages =128–45 |journal =The Cleft Palate Journal}} This still persists today in various parts of the world even though the intellectual development is often normal.{{cite book|last=Meulen|first=Jacobus Josephus Nicolaas Marie van der|title=On trigonocephaly|year=2009|publisher=Optima Grafische Communicatie|isbn=978-90-8559-601-1}} The Austrian physician Franz Joseph Gall presented the science of phrenology in the early 19th century through his work The Anatomy and Physiology of the Nervous System in General, and of the Brain in Particular.Phrenology. http://www.phrenology.org/

Hippocrates described trigonocephaly as follows: Men's heads are by no means all like to one another, nor are the sutures of the head of all men constructed in the same form. Thus, whoever has a prominence in the anterior part of the head (by prominence is meant the round protuberant part of the bone which projects beyond the rest of it), in him the sutures of the head take the form of the Greek letter 'tau', τ.Hippocrates. On injuries of the head. Med classics 1938: 3: 145-60.{{cite journal |year =2005 |last1 =Dimopoulos |first1 =VG |last2 =Machinis |first2 =TG |last3 =Fountas |first3 =KN |last4 =Robinson |first4 =JS |title =Head injury management algorithm as described in Hippocrates' "peri ton en cephali traumaton" |volume =57 |issue =6 |pages =1303–5; discussion 1303–5 |journal =Neurosurgery |doi =10.1227/01.NEU.0000187321.13149.B9 |pmid =16331180 |s2cid =26216660 }}

Hermann Welcker coined the term trigonocephaly in 1862. He described a child with a V-shaped skull and a cleft lip.Welcker H. Untersugungen uber wachtsum und bau des menschlischen Schädels. Leipzig: Engelmann, 1862.

Via a photo shown on a Facebook page, the mother of a child previously diagnosed with this condition recognised the symptoms and reported them to the family involved, resulting in an immediate diagnosis that medical professionals had overlooked in all earlier consultations.{{cite news |url=http://www.news.com.au/technology/british-mum-learns-baby-son-has-rare-condition-thanks-to-stranger-on-facebook/story-e6frfro0-1226350344950 |title=British mum learns baby son has rare condition thanks to stranger on Facebook |date=9 May 2012 |access-date=31 May 2012 |work=News.com.au |archive-date=11 June 2012 |archive-url=https://web.archive.org/web/20120611150053/http://www.news.com.au/technology/british-mum-learns-baby-son-has-rare-condition-thanks-to-stranger-on-facebook/story-e6frfro0-1226350344950 |url-status=dead }}

{{Reflist}}

{{Medical resources

| ICD11 = {{ICD11|LB70.0Y}}

| ICD10 = {{ICD10|Q|75|0|q|65}}

| ICD9 = {{ICD9|756.0}}

| ICDO =

| OMIM =190440

| OMIM_mult =

| MedlinePlus =

| eMedicineSubj =

| eMedicineTopic =

| DiseasesDB = 33252

}}

Category:Congenital disorders of musculoskeletal system