Antenatal diagnosis of spinal lipomas

Avoiding the antenatal counselling faux pas: bridging the gap between prenatal prognostication and postnatal outcome of closed spina bifida

PURPOSE

Closed spina bifida (CSB) is rare in prenatal literature, and various lesions are grouped under this broad nosological entity CSB, leading to confusing and misleading prognostic conclusions.

METHODS

This is a retrospective observational cohort study of prenatally detected CSB cases using two-dimensional ultrasound, complemented by three-dimensional ultrasonography and foetal MRI in indicated cases, from October 2014 to October 2021 in a tertiary-level single centre.

RESULTS

The most common upper vertebral level of CSB was lumbar in 66.6% (10/15). The sub-classification of lesions based on prenatal ultrasound showed an agreement in 53% of the cases. Sixty percent had associated abnormalities identified postnatally, the most common being anorectal malformation seen in 33.3%. On postnatal follow-up, 46.6% had bowel incontinence and bladder dysfunction, and 33.3% developed lower limb deformities.

CONCLUSIONS

All CSBs do not have a uniformly favourable prognosis. The prognosis of CSB depends on the pathological type, the presence of associated abnormalities and the management.

Fetal magnetic resonance imaging in the diagnosis of spinal cord neural tube defects: A prospective study

Objective

This study aimed to evaluate the value of fetal magnetic resonance imaging (MRI) in the prenatal diagnosis of spinal neural tube defects.

Methods

From August 2018 to January 2021, 56 fetuses with suspected spinal cord neural tube defects were treated by prenatal ultrasound in the Neurosurgery Department of the First Medical Center of the People's Liberation Army General Hospital. Fetal MRI was performed within 72 h after ultrasound diagnosis. Forty singleton fetuses were selected. Magnetic resonance examination was performed within 1 month after birth, and the diagnostic coincidence rates of prenatal ultrasound and fetal magnetic resonance examination in the prenatal diagnosis of spinal cord neural tube defects were compared and analyzed using postnatal magnetic resonance examination as the standard.

Results

The coincidence rates of prenatal ultrasound and fetal MRI for the prenatal diagnosis of spina bifida were 71.4% (20/28) and 39.2% (11/28), respectively, and the difference was statistically significant. The coincidence rates of prenatal ultrasound and fetal MRI in the diagnosis of intraspinal lipoma were 52.6% (10/19) and 73.7% (14/19), respectively, and the difference was statistically significant.

Conclusion

Fetal MRI has an advantage over prenatal ultrasound in detecting intraspinal lipoma. Prenatal ultrasound has an advantage over fetal MRI in detecting spina bifida.

Prenatal ultrasound diagnosis of neural tube defects in the era of intrauterine repair - Eleven years' experiences

OBJECTIVE

To modify the current neural tube defect (NTD) classification for fetal medicine specialists, and to investigate the impact of prenatal ultrasound conus medullaris position screening on the detection rate of closed spinal dysraphism and pregnancy outcomes.

MATERIALS AND METHODS

The clinical data of 112 patients prenatally diagnosed with neural tube defects in Taiji clinic from 2008 to 2018 were retrospectively analyzed. All cases were classified following the modified classification. We compared the detection rate before and after introducing the conus medullaris screening and pregnancy outcomes for NTD types.

RESULTS

Closed spinal dysraphism type prevailed in our sample (43.8%). The median gestational age at the time of detection for cranial dysraphism was 13.3 weeks, open spinal dysraphism was 22.0 weeks, and closed spinal dysraphism was 22.6 weeks. All cranial dysraphism (n = 43) and open spinal dysraphism cases (n = 20) had pregnancies terminated. For closed spinal dysraphism Class 1, the live-birth rate was 100.0% in the cases without other anomalies and 33.3% in the cases with other anomalies, respectively (X² = 17.25, p < 0.001). Similarly, for Class 2, pregnancy continuation rate was 50.0% in cases without other anomalies and 20.0% in cases with other anomalies, yet it failed to reach statistical significance (X² = 0.9, p = 0.524).

CONCLUSION

Our case series may help to improve early screening and prenatal diagnosis of NTDs. Modified classification is adjusted for use in ultrasound fetal care facilities, which could be used for predicting pregnancy outcome. We suggest promoting first-trimester anatomical screening in order to make an earlier diagnosis and therefore provide better prenatal care for open spinal dysraphism cases in the era of intrauterine repair. Our findings imply that the use of fetal conus medullaris position as a marker for closed spinal dysraphism improves the detection rate and would unlikely lead to a higher termination rate.

Results of the prophylactic surgery of lumbosacral lipomas 20 years of experience in the Paediatric Neurosurgery Department La Timone Enfants Hospital, Marseille, France

We conducted a retrospective study of children with lumbosacral lipomas treated in the Department of Pediatric Neurosurgery hospital Timone Enfants in the last 20 years. We selected patients with lipomas of the conus medullaris who underwent preventive surgery. 86 ,4 % of the patients remained asymptomatic during the follow-up. Worse results were observed in children older than one year old at surgery with transitional lipoma, with the conus medullaris was below L5 and when the resection had been partial. In view of the results, the authors recommend the preventive surgery before the first year of life under neurophysiologic monitoring in order to perform a total near-total resection with a neural plate reconstitution.

Multidisciplinary management of spinal lipoma

Spinal lipomas (congenital lipomyelomeningoceles) can cause significant aesthetic deformity of the lower spine in addition to recognised neurological problems. Surgical management consists of untethering the cord in symptomatic cases, and debulking of the lipomatous component to improve the spinal contour. However, management remains controversial. Between May 1998 and November 2002, 23 cases of lumbosacral spinal lipoma were operated on by neurosurgeons at our hospital. Of these, eight (34%) patients were subsequently referred to plastic surgery for aesthetic revision, which was performed by a combined team of plastic surgeons and neurosurgeons. In addition, three new patients had their primary surgery as a planned procedure performed by the same combined team. The purpose of this paper is to present the method and results of combined plastic surgery and neurosurgery technique in these 11 cases of spinal lipoma. Follow up ranged between 12 months and 4 years (mean 20 months). One patient had wound break down and three patients developed seroma. Two patients had cerebrospinal fluid (CSF) leakage which required re-exploration and prolonged hospitalisation. The aesthetic results were very satisfactory in 10 out of the 11 patients. The frequency of secondary referral for aesthetic revision, together with the incidence of CSF leak, underlines the importance of managing spinal lipomas in a multidisciplinary team involving neurosurgeons and plastic surgeons. This series demonstrates that aesthetic results are encouraging but decreasing the CSF leakage rate remains a challenge. Further follow up will determine the role of early combined surgery in the management of spinal lipoma.

Prenatal diagnosis of open and closed spina bifida

OBJECTIVE

To identify criteria useful for differentiating closed from open spina bifida antenatally.

PATIENTS AND METHODS

A retrospective study of cases of spina bifida diagnosed in a referral center between 1997 and 2004.

RESULTS

Of 66 cases of fetal spina bifida diagnosed at a median gestational age of 21 (range, 16-34) weeks, detailed follow-up was available for 57. Of these, open defects were found in 53 (93.0%) and closed defects in four (7.0%). Closed spina bifida was associated in two cases with a posterior cystic mass with thick walls and a complex appearance, while in two cases the spinal lesion could not be clearly differentiated from an open defect, particularly at mid-gestation. Open spina bifida was always associated with typical alterations of cranial anatomy, including the so-called 'banana' and 'lemon' signs, while in closed spina bifida the cranium was unremarkable. When the data were available, levels of amniotic fluid alpha-fetoprotein were always abnormally elevated with open spina bifida and within normal limits with closed forms.

CONCLUSION

In this study 7% of cases of spina bifida diagnosed in utero were closed. The differentiation between open and closed forms is best shown by the sonographic demonstration of abnormal or normal cranial anatomy.