日本未熟児新生児学会雑誌　第20巻　第1号　53～58頁（2008年）

日本未熟児新生児学会雑誌　20(1)：53-58；2008　

受付日：平成18．12．21

受理日：平成19．02．22

頭部エコーの脳室拡大を契機に診断した，後頭蓋窩硬膜下血腫，二次性水頭症の早産極低出生体重児例

A Case of Posterior Fossa Subdural Hematoma in a Preterm Very Low Birth Weight Infant

＊1旭川厚生病院　小児科，＊2北海道立子ども総合医療・療育センター　新生児科

＊1 Department of Pediatrics, Asahikawa Kosei Hospital，＊2 Department of Neonatology, Hokkaido Medical Center for Child Health and Rehabilitation

岡本年男＊1・小久保雅代＊1・梶野真弓＊1・高瀬雅史＊1・白井　勝＊1・坂田　宏＊1・新飯田裕一＊2・沖　潤一＊1

Toshio OKAMOTO＊1，Masayo KOKUBO＊1，Mayumi KAJINO＊1，Masashi TAKASE＊1， Masaru SHIRAI＊1，Hiroshi SAKATA＊1，Yuuichi NIIDA＊2 ，Junichi OKI＊1

Key Words：posterior fossa subdural hematoma, secondly hydrocephalus, very low birth weight infant, surgical evacuation and brain stem compression

　症例は在胎期間31週2日，出生体重1,328gの女児。母体妊娠高血圧症，胎児発育不良，胎児心拍異常のため緊急帝王切開となり，頭位で仮死なく出生した。急性期の頭部エコーでは，頭蓋内出血や脳室拡大を認めなかったが，日齢14の頭部エコーで脳室拡大を認め，日齢18の頭部MRIで後頭蓋窩硬膜下血腫および二次性水頭症と診断した。脳幹症状の出現が懸念され，日齢22に外科治療可能な北海道立小児総合保健センター（現・北海道立子ども総合医療・療育センター）に転院した。転院後の日齢25に状態が急変したため，緊急血腫除去術が施行され，後遺症なく退院した。周産期の硬膜下血腫は一般に成熟児の分娩外傷で発症するが，極低出生体重児では帝王切開分娩出生でも合併することがある。したがって，頭部エコーで脳室拡大を認めた際には後頭蓋窩硬膜下血腫も念頭におき診断することが重要である。さらに本症発症の際には脳幹症状の出現に注意し，外科治療の時期を逃さないことが重要である。

　We reported a very low birth weight infant with posterior fossa subdural hematoma and secondly obstructive hydrocephalus. A female infant was born by emergency caesarean section at 31 weeks and 2 days of gestation, because of pregnancy-induced hypertension, intrauterine growth retardation and suspicion of non-reassuring fetal status. She was weighted 1,328g at birth and 1-minute Apgar score was 7. Cranial ultrasound scan performed at 3 days after birth was normal. The routine ultrasound scan at 14 days after birth demonstrated the marked ventricular dilation. A magnetic resonance imaging（MRI）performed at 18 days after birth confirmed a massive posterior fossa subdural hematoma and obstructive hydrocephalus. Although she developed no neurological signs, we transferred her to Hokkaido Children’s Hospital and Medical Center at 22 days after birth to be able to receive the neurosurgical treatment. The neurological signs such as seizures, vomiting and respiratory distress were observed after the transfer. She required intubation and ventilation. As the symptoms were indicative of ongoing brain stem compression, neurosurgical evacuation of hematoma was performed at 25 days after birth. After the operation, the symptoms were improved immediately. Subsequent MRI showed complete evacuation of hematoma and resolve of hydrocephalus. She is now four months old and is developmentally normal. Although posterior fossa subdural hematoma is a rare condition in a preterm very low birth weight infant who was born by caesarean section, clinicians should be aware of this life-threatening complication if cranial ultrasound revealed ventricular dilation. The early diagnosis of posterior fossa subdural hematoma is very important and there should be no delay in surgery if clear neurological deterioration becomes apparent.