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The first 25 slides, exactly as they appear. The full deck has 67 content slides.
Radiology
Holt-Oram Syndrome
Built from Obstetric Imaging
What’s inside
10 sections · 67 slides
Overview
What the syndrome is, what it hits, and who first saw it
- Definition of Holt-Oram syndrome
- Organ systems involved
- First description of the syndrome
- Features linked to a TBX5 variant
Genetics and inheritance
One gene, one faulty copy, and a family tree that shows it
- The TBX5 gene
- Location of TBX5 on chromosome 12
- How a TBX5 fault causes disease
- Route from gene fault to clinical picture
- Types of pathogenic TBX5 variants
- Yield of TBX5 genetic testing
- Where the faulty gene comes from
- 12q24.1
- Autosomal dominant inheritance
- Family tree of an autosomal dominant condition
- Penetrance and expressivity
Prevalence and diagnostic criteria
How common it is, and the rules used to call it
- Prevalence and sex distribution
- Why modern prevalence estimates are lower
- Clinical diagnostic criteria
- Molecular diagnosis
- Clinical versus molecular diagnosis
Upper limb malformations
Always present, always on the thumb side, usually on both arms
- Upper limb involvement
- Symmetry and distribution of skeletal defects
- Radial longitudinal deficiency of the upper limb
- Hand radiograph with a hypoplastic index ray
- Thumb malformations
- Thumb malformation and syndactyly
- Thumb and index finger syndactyly
Cardiac malformations
Holes in the dividing walls, and faults in the wiring
- Frequency of congenital heart disease
- Septal defects
- Atrial septal defect
- Ventricular septal defect
- Complex congenital heart disease
- Cardiac conduction disease
- Cardiac conduction system
- Where conduction disease strikes
- Dilated cardiomyopathy in adulthood
Other features and variability
What else can be malformed, and why families look different
- Chest wall and vertebral anomalies
- Intellectual development
- Variability within families
- Avoiding misdiagnosis
Prenatal imaging
What ultrasound can show, what it misses, and what to scan
- Prenatal diagnosis by ultrasound
- Sonographic assessment of the upper limbs
- Limitations of ultrasound for limb anomalies
- Three-dimensional ultrasonography
- Fetal echocardiography
- Classic sonographic signs
- Prenatal work-up when the syndrome is suspected
Differential diagnosis
Other causes of a malformed radial ray with or without a heart defect
- Differential diagnosis of radial ray defects
- Further syndromic differential diagnoses
- Non-genetic causes to consider
- Separating Holt-Oram syndrome from its mimics
Management and counselling
Before birth, after birth, and what the family needs to know
- Prenatal management
- Evaluation of the parents
- Recurrence risk and reproductive options
- Germline mosaicism
- Recurrence risk by parental status
- The postnatal multidisciplinary team
- Postnatal cardiac management
- Postnatal management of the upper limb
Summary
What the referring physician needs to know
- What the referring physician needs to know
- Key points on the phenotype
- Key points on the genetics
- References
- References (continued)
- References (continued)
- References (continued)
- Obstetric Imaging: Fetal Diagnosis and Care, 2nd Edition