Evaluation of fetal thymus size in pregnancies complicated with fetal growth restriction

Öz

Aim: To evaluate fetal thymus size using the thymic-thoracic ratio (TTR) in women with a pregnancy complicated with fetal growth restriction (FGR) and to assess the relationship with adverse perinatal outcomes. Materials and Method: A total of 35 pregnant women with FGR and 42 healthy pregnant women with similar demographic characteristics were included in this prospective study. In the FGR group, cases with pathological doppler flow parameters of absent end-diastolic flow (AEDF) in an umbilical artery and cerebroplacental ratio (CPR) <1 and estimated fetal weight (EFW) <3rd percentile were also recorded. The groups were compared in terms of demographic features, clinical and sonographic characteristics and fetal TTR. In the statistical analysis of the data obtained, the Mann-Whitney U and Fisher's Exact tests were used to compare the median values of the groups and categorical variables. The association between fetal TTR and adverse perinatal outcomes was investigated using Spearman's correlation coefficient. The level of statistical significance was set at p<0.05. Results: Other than the adverse perinatal outcomes of EFW <3rd percentile, oligohydramnios, pathological doppler flow, all the other parameters were similar in both groups (p>0.05). The fetal TTR was determined to be significantly lower in the FGR group than in the control group (0.37±0.02 [0.33-0.42] and 0.40±0.02 [0.36-0.45], p<0.001, respectively). A statistically significant, negative moderate correlation was determined between fetal TTR and the EFW <3rd percentile, pathological doppler flow (AEDF and CPR<1) (r= -0.703, r= -0.588, r= -0.383, r= -0.418 and p<0.001, p<0.001, p=0.023, p=0.012, respectively). Conclusion: This is the first study to have evaluated the fetal TTR measurement in FGR-complicated pregnancies. A lower fetal TTR supports the relationship between FGR and fetal thymic involution. Moreover, fetal TTR might be a sonographic indicator for predicting adverse perinatal outcomes.

Anahtar Kelimeler

• Fetal growth restriction
• thymic-thoracic ratio
• ultrasound

Fetal büyüme kısıtlılığı ile komplike gebeliklerde fetal timus boyutunun değerlendirilmesi

Öz

Amaç: Fetal büyüme kısıtlılığı (FBK) ile komplike gebeliği olan kadınlarda timik-torasik oran (TTR) kullanarak fetal timus boyutunu değerlendirmek ve olumsuz perinatal sonuçlarla olan ilişkisini belirlemek. Gereçler ve Yöntem: Bu prospektif çalışmaya FBK ile komplike toplam 35 gebe kadın ile benzer demografik özellikte sağlıklı toplam 42 gebe kadın dahil edildi. FBK grubunda, patolojik doppler akım parametreleri olan umbilikal arterde end-diyastolik akım kaybı (EDAK) ve serebroplasental oran (SPO) <1 olan ve tahmini fetal ağırlığı (TFA) <3. persantil olan olgular ayrıca kayıt altına alındı. Gruplar arasında demografik özellikler, klinik ve sonografik özellikler ve fetal TTR açısından karşılaştırmalar yapıldı. Elde edilen verilerin istatistiksel analizinde, gruplar arası ortanca (median) değerlerin ve kategorik değişkenlerin karşılaştırılmalarında Mann-Whitney U ve Fisher’s Exact testleri kullanıldı. Fetal TTR ile olumsuz perinatal sonuçlar arasındaki ilişki Spearman korelasyon katsayısı ile araştırıldı. P<0.05 değeri istatistiksel olarak anlamlı kabul edildi. Bulgular: TFA <3. persantil, oligohidramniyoz, patolojik doppler akımı dışındaki olumsuz perinatal sonuçlar ve diğer parametreler her iki grupta da benzerdi (p>0.05). Fetal TTR'nin FBK grubunda kontrol grubuna göre anlamlı derecede daha düşük olduğu belirlendi (0.37±0.02 [0.33-0.42] ve 0.40±0.02 [0.36-0.45], p<0.001, sırasıyla). Fetal TTR ile TFA <3. persantil, patolojik doppler akımı (EDAK ve SPO <1) arasında istatistiksel olarak anlamlı, orta düzeyde negatif bir korelasyon saptandı (r= -0.703, r= -0.588, r= -0.383, r= -0.418 ve p<0.001, p<0.001, p=0.023, p=0.012, sırasıyla). Sonuç: FBK ile komplike gebeliklerde fetal TTR ölçümünün değerlendirildiği ilk çalışmadır. Düşük fetal TTR, FBK ile fetal timik involusyon ilişkisini desteklemektedir. Bununla birlikte, olumsuz perinatal sonuçların öngörüsünde fetal TTR bir sonografik indikatör olabilir.

Anahtar Kelimeler

• Fetal büyüme kısıtlılığı
• timik-torasik oran
• ultrason

Kaynakça

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