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Lemon sign

MedGen UID:
1671076
•Concept ID:
C4700166
•
Sign or Symptom
Synonym: lemon sign
 
HPO: HP:0032269

Definition

The lemon sign refers to the shape of the fetal skull at ultrasonography (US) when the frontal bones lose their normal convex contour and appear flattened or inwardly scalloped. This gives the skull a shape that is said to resemble a lemon.. The sign is seen on transverse sonograms of the fetal cranium obtained at the level of the ventricles. [from HPO]

Term Hierarchy

CClinical test,  RResearch test,  OOMIM,  GGeneReviews,  VClinVar  
  • CROGVLemon sign

Professional guidelines

PubMed

Prenatal diagnosis and postnatal outcome of closed spinal dysraphism.
Bedei I, Krispin E, Sanz Cortes M, Lombaard H, Zemet R, Whitehead WE, Belfort MA, Huisman TAGM
Prenat Diagn 2024 Apr;44(4):499-510. Epub 2023 Nov 27 doi: 10.1002/pd.6454. PMID: 38013494
Comparison between MRI and the Combination of 2D and 3D US in the Prenatal Diagnosis of Closed Spina Bifida.
Zhang W, Wang J, Wu H, Chen L
Pediatr Neurosurg 2023;58(6):392-400. Epub 2023 Sep 12 doi: 10.1159/000533205. PMID: 37699379
Prenatal diagnosis of spina bifida: from intracranial translucency to intrauterine surgery.
Sepulveda W, Wong AE, Sepulveda F, Alcalde JL, Devoto JC, Otayza F
Childs Nerv Syst 2017 Jul;33(7):1083-1099. Epub 2017 Jun 7 doi: 10.1007/s00381-017-3445-7. PMID: 28593553

Recent clinical studies

Etiology

Prenatal diagnosis and postnatal outcome of closed spinal dysraphism.
Bedei I, Krispin E, Sanz Cortes M, Lombaard H, Zemet R, Whitehead WE, Belfort MA, Huisman TAGM
Prenat Diagn 2024 Apr;44(4):499-510. Epub 2023 Nov 27 doi: 10.1002/pd.6454. PMID: 38013494
Hindbrain Herniation and Banana and Lemon Sign After Open Fetal Myelomeningocele Repair - When Do These Signs Disappear and is Shunting Predictable?
Vonzun L, Winder FM, Meuli M, Moehrlen U, Mazzone L, Kraehenmann F, Huesler M, Zimmermann R, Ochsenbein-Kölble N
Ultraschall Med 2021 Oct;42(5):514-519. Epub 2020 Apr 24 doi: 10.1055/a-1112-7096. PMID: 32330995
Impact of introduction of mid-trimester scan on pregnancy outcome of open spina bifida in The Netherlands.
Fleurke-Rozema JH, Vogel TA, Voskamp BJ, Pajkrt E, van den Berg PP, Beekhuis JR, Bilardo CM, Brouwer OF, de Walle HE, Snijders RJ
Ultrasound Obstet Gynecol 2014 May;43(5):553-6. Epub 2014 Feb 10 doi: 10.1002/uog.12546. PMID: 23828717
Prenatal diagnosis of neural tube defect before 12 weeks' gestation: direct and indirect ultrasonographic semeiology.
Bernard JP, Suarez B, Rambaud C, Muller F, Ville Y
Ultrasound Obstet Gynecol 1997 Dec;10(6):406-9. doi: 10.1046/j.1469-0705.1997.10060406.x. PMID: 9476326
Ultrasound screening for spina bifida: cranial and cerebellar signs.
Nicolaides KH, Campbell S, Gabbe SG, Guidetti R
Lancet 1986 Jul 12;2(8498):72-4. doi: 10.1016/s0140-6736(86)91610-7. PMID: 2425202

Diagnosis

Prenatal diagnosis and postnatal outcome of closed spinal dysraphism.
Bedei I, Krispin E, Sanz Cortes M, Lombaard H, Zemet R, Whitehead WE, Belfort MA, Huisman TAGM
Prenat Diagn 2024 Apr;44(4):499-510. Epub 2023 Nov 27 doi: 10.1002/pd.6454. PMID: 38013494
Prenatal diagnosis of spina bifida: from intracranial translucency to intrauterine surgery.
Sepulveda W, Wong AE, Sepulveda F, Alcalde JL, Devoto JC, Otayza F
Childs Nerv Syst 2017 Jul;33(7):1083-1099. Epub 2017 Jun 7 doi: 10.1007/s00381-017-3445-7. PMID: 28593553
Sonographic detection of open spina bifida in the first trimester: review of the literature.
Meller C, Aiello H, Otaño L
Childs Nerv Syst 2017 Jul;33(7):1101-1106. Epub 2017 May 16 doi: 10.1007/s00381-017-3443-9. PMID: 28510070
The "lemon" sign: a clinical perspective.
Filly RA
Radiology 1988 May;167(2):573-5. doi: 10.1148/radiology.167.2.3282266. PMID: 3282266
Ultrasound screening for spina bifida: cranial and cerebellar signs.
Nicolaides KH, Campbell S, Gabbe SG, Guidetti R
Lancet 1986 Jul 12;2(8498):72-4. doi: 10.1016/s0140-6736(86)91610-7. PMID: 2425202

Prognosis

Cranial findings detected by second-trimester ultrasound in fetuses with myelomeningocele: a systematic review.
Kunpalin Y, Richter J, Mufti N, Bosteels J, Ourselin S, De Coppi P, Thompson D, David AL, Deprest J
BJOG 2021 Jan;128(2):366-374. doi: 10.1111/1471-0528.16496. PMID: 32926566Free PMC Article
Hindbrain Herniation and Banana and Lemon Sign After Open Fetal Myelomeningocele Repair - When Do These Signs Disappear and is Shunting Predictable?
Vonzun L, Winder FM, Meuli M, Moehrlen U, Mazzone L, Kraehenmann F, Huesler M, Zimmermann R, Ochsenbein-Kölble N
Ultraschall Med 2021 Oct;42(5):514-519. Epub 2020 Apr 24 doi: 10.1055/a-1112-7096. PMID: 32330995
Impact of introduction of mid-trimester scan on pregnancy outcome of open spina bifida in The Netherlands.
Fleurke-Rozema JH, Vogel TA, Voskamp BJ, Pajkrt E, van den Berg PP, Beekhuis JR, Bilardo CM, Brouwer OF, de Walle HE, Snijders RJ
Ultrasound Obstet Gynecol 2014 May;43(5):553-6. Epub 2014 Feb 10 doi: 10.1002/uog.12546. PMID: 23828717
Prenatal diagnosis of neural tube defect before 12 weeks' gestation: direct and indirect ultrasonographic semeiology.
Bernard JP, Suarez B, Rambaud C, Muller F, Ville Y
Ultrasound Obstet Gynecol 1997 Dec;10(6):406-9. doi: 10.1046/j.1469-0705.1997.10060406.x. PMID: 9476326
The "lemon" sign: a clinical perspective.
Filly RA
Radiology 1988 May;167(2):573-5. doi: 10.1148/radiology.167.2.3282266. PMID: 3282266

Clinical prediction guides

Prenatal diagnosis and postnatal outcome of closed spinal dysraphism.
Bedei I, Krispin E, Sanz Cortes M, Lombaard H, Zemet R, Whitehead WE, Belfort MA, Huisman TAGM
Prenat Diagn 2024 Apr;44(4):499-510. Epub 2023 Nov 27 doi: 10.1002/pd.6454. PMID: 38013494
Hindbrain Herniation and Banana and Lemon Sign After Open Fetal Myelomeningocele Repair - When Do These Signs Disappear and is Shunting Predictable?
Vonzun L, Winder FM, Meuli M, Moehrlen U, Mazzone L, Kraehenmann F, Huesler M, Zimmermann R, Ochsenbein-Kölble N
Ultraschall Med 2021 Oct;42(5):514-519. Epub 2020 Apr 24 doi: 10.1055/a-1112-7096. PMID: 32330995
The lemon sign: not a specific indicator of meningomyelocele.
Ball RH, Filly RA, Goldstein RB, Callen PW
J Ultrasound Med 1993 Mar;12(3):131-4. doi: 10.7863/jum.1993.12.3.131. PMID: 8492374
The "lemon" sign: a clinical perspective.
Filly RA
Radiology 1988 May;167(2):573-5. doi: 10.1148/radiology.167.2.3282266. PMID: 3282266
Ultrasound screening for spina bifida: cranial and cerebellar signs.
Nicolaides KH, Campbell S, Gabbe SG, Guidetti R
Lancet 1986 Jul 12;2(8498):72-4. doi: 10.1016/s0140-6736(86)91610-7. PMID: 2425202

Recent systematic reviews

Cranial findings detected by second-trimester ultrasound in fetuses with myelomeningocele: a systematic review.
Kunpalin Y, Richter J, Mufti N, Bosteels J, Ourselin S, De Coppi P, Thompson D, David AL, Deprest J
BJOG 2021 Jan;128(2):366-374. doi: 10.1111/1471-0528.16496. PMID: 32926566Free PMC Article

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