Evaluation of conus medullaris level in newborn infants

Yıl 2023, Cilt: 48 Sayı: 2, 629 - 636, 02.07.2023

Bülent Yıldız , Gaffari Tunç , Burçak Söylemez

https://doi.org/10.17826/cumj.1241867

Öz

Purpose: Previous studies have reported that the conus medullaris (CM) is located between T12 and L2 in most adults, but no significant ascent has been observed during childhood. There is evidence that the normal position of the CM in an adult is acquired at birth in the majority of cases. Studies have shown that there are differences in CM levels in neonates. This situation causes problems for interventional procedures in the neonatal period. The aim of this study is to determine CM levels in preterm/term neonates using ultrasound (US).
Materials and Methods: Newborn infants (gestational age: 24–43 weeks) admitted to the neonatal intensive care unit between March 2020 and June 2021 were evaluated for CM levels by the postnatal US. Infants with central nervous system abnormalities, dysmorphic features, somatic or various genetic diseases, or their parent’s refusal to participate were excluded from the study.
Results: Of the 189 neonates infants included in our study, 85 (44.6%) were female, 104 (55.4%) were male, 139 (73.54%) were preterm (24–36 weeks), and 50 (26.46%) were term (37–42 weeks) neonates. As a result of the US performed on the first day of 189 neonates, CM levels, 31 (16.4%) were L1, 31 (16.4%) were L1-2, and 71 (37.6%) were L2. There is a strong correlation between birth weight and birth week (r 0.84). There is a negative relationship between birth weight and CM level (r -0,20), gestational age, and CM level (r -0,23).
Conclusion: Conus medullaris level was negatively correlated with gestational age and increased with advancing gestational age. In addition, the CM level shows a slower rise at 28-40 weeks of postmenstrual age and reaches the normal level (L1-L2) in the neonatal period, as in adults. Knowing the level of the CM in the newborn period will ensure that spinal procedures such as lumbar puncture to be applied to the spinal region can be performed safely.

Anahtar Kelimeler

Newborn infant, ultrasound, Conus medullaris level

Destekleyen Kurum

YOK

Proje Numarası

YOK

Teşekkür

We would like to thank Ziynet Çınar, Faculty Member of the Biostatistics Department of Sivas Cumhuriyet University, for her contributions to the study and her assistance in this project. The authors would like to thank all the infant and their families who participated in this study.

Yenidoğan bebeklerde konus medullaris düzeyinin değerlendirilmesi

Öz

Amaç: Yapılan araştırmalar, çoğu yetişkinde konus medullaris (KM) seviyesinin T12 ve L2 arasında olduğunu, ancak çocuklukta önemli bir KM yükselişinin olmadığını göstermektedir. Normal yetişkin pozisyonunun aslında vakaların çoğunda doğumla elde edildiğine dair kanıtlar mevcuttur. Yapılan çalışmalarda yenidoğanlarda KM seviyesinde farklılıklar olduğunu göstermiştir. Bu durum yenidoğan döneminde yapılacak girişimsel işlemlerde soruna neden olmaktadır. Bu çalışmada amacımız preterm/term yenidoğanlarda ultrason (US) kulanılarak KM seviyesini tespit etmektir.
Gereç ve Yöntem: Yenidoğan Yoğun Bakım Ünitesi’nde (YYBU) Mart 2020- Haziran 2021 tarihleri arasında kabul edilen preterm/term yenidoğanlarda (gestasyonel haftası 24-43) postnatal US ile KM seviyeleri değerlendirildi. Çalışmada santral sinir sistemi anomalileri, dismorfik vücut bulguları olan, somatik veya çeşitli genetik hastalığı olan olgular ve çalışmayı kabul etmeyen ailelerin bebekleri çalışma dışı bırakıldı.
Bulgular: Çalışmamıza dahil edilen 189 yenidoğanın 85'i (%44,6) kız, 104'ü (%55,4) erkek, 139'u (%73,54) preterme (24-36 hafta) ve 50'si (%26,46) term (37-42 hafta) bebekti. İlk gün yapılan US sonucunda KM seviyesinin 31’i (%16,4) L1, 31’i (%16,4) L1-2 ve 71’i (%37,6) L2 olduğu gözlemlendi. Doğum ağırlığı ile doğum haftası arasında güçlü bir ilişki bulundu (r 0.84). KM seviyesi ile doğum haftası (r -0,23) ve doğum ağırlığı (r -0,20) ile arasında negatif yönlü bir ilişki saptandı.
Sonuç: Konus medullaris seviyesi gebelik haftası ile negatif ilişkiliydi ve ilerleyen gebelik yaşı ile yükseliyordu. Ayrıca konus medullaris postmenstural 28-40 haftalarda daha yavaş bir yükselme göstermektedir ve yenidoğan döneminde erişkindeki gibi normal düzeye (L1-L2) ulaşmıştır. Yenidoğan döneminde konus medullarisin seviyesinin bilinmesi spinal bölgeye uygulanacak lomber ponksiyon gibi işlemlerin güvenle yapılabilmesini sağlayacaktır.

Anahtar Kelimeler

Yenidoğan bebek, ultrasound, Konus medullaris düzeyi

Proje Numarası

YOK

Kaynakça

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