Postmortem MR in termination of pregnancy for central nervous system (CNS) anomalies

Figures & data

Figure 1. Flowchart included and excluded cases. TOP: termination of pregnancy; CNS: central nervous system; PMMR: postmortem MR; PI: Pathological investigations. Genetic anomaly: chromosomal anomaly + anomaly detectable by array comparative genomic hybridization (CGH).

Table 1. Conventional autopsy provides more information than postmortem.

	Prenatal diagnosis	GA diagnosis	Diagnosis US	Diagnosis MR	GA @ TOP	Additional findings on CA, not detected by PMMR	Impact on counseling
1	CC dysgenesis, polymicrogyria	23 wks	+	+	26 wks	CC lipoma, CMV fetopathy	Yes , major additional finding
2	Arthrogryposis, abnormal midline	17 wks	+	Not performed	18 wks	Polymicro-gyria	Yes , major additional finding
3	MC, delayed gyration	22 wks	+	+	23 wks	Calcifications	No,minor additional finding
4	Cerebral tumor	28 wks	+	+	29 wks	Teratoma	No, prenatally detected
5	NTD, truncus arteriosus	20 wks	+	Not performed	22 wks	Facial dysmorphism	No,minor additional finding
6	NTD	33 wks	+	+	33 wks	Talipes	No,minor additional finding
7	Exencephaly, TI	12 wks	+	Not performed	13 wks	Tricuspid dysplasia	No, prenatally detected
8	PMS with MC, delayed gyration, AVSD	22 wks	+	Not performed	23 wks	AVSD	No, prenatally detected

AVSD: atrioventricular septal defect; CA: conventional autopsy; CC: corpus callosum; CMV: cytomegalovirus; MC: microcephaly; MR, impact on parental counseling after correlation with prenatal diagnosis; NTD: neural tube defect; PM MR: postmortem magnetic resonance; PMS: polymalformative syndrome; TI: tricuspid insufficiency.

Table 2. Cases in which PM MR detects major additional findings, undetected prenatally and undetected by CA, influencing final diagnosis and parental counseling.

	Prenatal Diagnosis	GA @ diagnosis	US diagnosis	MRI diagnosis	GA @ TOP	Additional findings on PMMR, not detected by CA	Impact on counseling
1	Hydrocephalus, abnormal posterior fossa	21 weeks	+	Not performed	22	Aqueductal stenosis	Yes, major additional finding
2	PMS, arthrogryposis, extreme cerebellar hypoplasia	17 weeks	+	Not performed	18	Cerebral cysts and clefts,dilated venous sinuses	Yes, major additional finding
3	Arthrogryposis, hydrocephalus, CC dysgenesis, cerebellar hypoplasia	24 weeks	+	+	26	Cerebral cysts and clefts	Yes, major additional finding
4	Hydrocephalus, cerebellar hypoplasia, aqueductal stenosis	25 weeks	+	+	26	Vertebral anomalies	Yes, major additional finding
5	Cerebellar hypoplasia	17 weeks	+	Not performed	18	Vertebral and rib anomalies	Yes, major additional finding

CA: conventional autopsy; CC: corpus callosum; PM MR: postmortem magnetic resnonance; PMS: polymalformative syndrome.

Figure 2. Distribution of detected CNS anomalies. X-axis = number of cases. ISV = isolated severe ventriculomegaly; NTD = neural tube defect.

Figure 3. Case: Prenatal diagnosis of hydrocephalus, cerebellar hypoplasia and aqueductal stenosis. TOP at GA 27 weeks. PM MR shows hydrocephalus, rhombencephalosynapsis, CC dysgenesis, vertebral anomalies. CA shows hydrocephalus, rhombencephalosynapsis, CC dysgenesis. Vertebral anomalies are only depicted on PM MR, demonstrating superiority of PM MR over CA in this case. (a) T2-weighted image of the brain in the axial plane. Dilated right temporal horn of the lateral ventricle (black star). Black fluid surrounding the cerebellum (white arrows). The dentate nuclei appear fused (White circle) and there is no vermian structure visible (curved white line). (b) T2-weighted image of the brain in the axial plane. Severe ventriculomegaly with blood layering as a normal post mortem finding and destruction of the leaflets of the cavum septi pellucidi (thin black arrow). Furthermore, the normal layering of the cerebral mantle is seen with the germinative matrix, subventricular zone, subplate and cortical plate. (c) T1-weighted image of the body in the coronal plane. Abnormal ossification of a thoracic vertebral body (T11) in the lower half of the thoracic spine. (d) T1-weighted image of the body in the coronal plane. Abnormal ossification of two thoracic vertebral bodies (T1 and T4) in the upper half of the thoracic spine.

Table 3. The time interval between feticide, delivery and PM MR in different groups with and without feticide or autolysis.

	Time delay (h) Feticide-Delivery	Time delay (h) Delivery-PM MR	Time delay (h) Feticide-PM MR	Mean GA (weeks)
Feticide+/Autolysis+ (n = 18)*	28	8	37	26.9 (SD 4.48)
Feticide+/Autolysis− (n = 28)**	21	6	27	27.6 (SD 3.87)
Feticide−/Autolysis+ (n = 4)	NA	7	NA	18.5 (SD 3.42)
Feticide−/Autolysis- (n = 18)	NA	7	NA	18.6 (SD 3.66)

Time delay in hours, Gestational age in weeks. Autolysis+: autolysis was present; Autolysis−: no autolysis was present; Feticide+: feticide was performed; Feticide−: no feticide was performed; GA: gestational age; h: hours; NA: not applicable; PMMRI: postmortem magnetic resonance imaging ; Data missing in *3 **1 patients.