Table 2 Benefits and drawbacks of different post-mortem imaging modalities for perinatal loss
From: A pragmatic evidence-based approach to post-mortem perinatal imaging
|  | Radiographs | Ultrasound | CT | MRI (3 T or 1.5 T) | Micro-CT | High-field MRI (7 T +) |
|---|---|---|---|---|---|---|
Availability | Easily available | Easily available | Easily available | Moderate | Limited: few select centres/research facilities | Limited: few select centres/research facilities |
Cost | Cheap | Cheap | Cheap | Expensive +  | Same cost as CT scanner | Expensive +  +  |
Size of foetus | Any size | Any size—although intrauterine retention time may affect image quality | Technically feasible, but poor diagnostic accuracy and lack of internal contrast from lack of body fat | Better for larger foetuses, poorer for body weight < 500 g | Up to 30 cm in length, limited by scanner bore | Similar to micro-CT |
Advantages | Easy to perform, already part of routine autopsy service | Ease of access, cheap and portable Facilitates image-guided biopsies | Highest accuracy for intracranial and musculoskeletal trauma (older children; trauma) | Multiple sequences, multiplanar reconstructions | Excellent resolution and soft tissue detail Excellent bone detail without exogenous contrast | Excellent resolution and soft tissue detail No need for exogenous contrast |
Drawback | No internal soft tissue detail Only useful in minority (< 5%) of cases | Operator dependent Requires a hands-on approach (radiologist) | Poor soft tissue detail due to lack of internal body fat | Availability/access may be limited Poorer resolution in smaller foetuses | Iodine contrast is required for soft tissue detail, which can cause tissue discoloration | Expensive, limited access, long scanning times (hours) |
Indication: | Estimation of foetal gestational age, diagnosis of skeletal dysplasias and limb anomalies | Assessment of soft tissue/ internal organ detail | Bony injuries; trauma; consider for skeletal dysplasias or trauma (although radiographs better and cheaper) | Assessment of soft tissue/ internal organ detail | Small foetuses (< 20-week gestation) where ultrasound and 1.5 T/3 T MRI non-diagnostic | Currently research tool only |