Use of bipedicular advancement flaps for intrauterine closure of myeloschisis

Intrauterine closure of myelomeningocele defects with primary linear repair versus bipedicle fasciocutaneous flaps: a post-MOMS cohort study with long-term follow-up

OBJECTIVE

The objective of this study was to determine the effects of in utero bipedicle flaps on maternal-fetal morbidity/mortality, the need for CSF diversion, and long-term functional outcomes.

METHODS

Eighty-six patients who underwent fetal myelomeningocele repair from 2011 to 2021 at a single institution were reviewed. Primary outcomes included intrauterine fetal demise, postnatal death, postnatal myelomeningocele repair dehiscence, and CSF diversion by final follow-up.

RESULTS

The cohorts were no different with regard to race, ethnicity, maternal age at fetal surgery, body mass index, gravidity, parity, gestational age at fetal surgery, estimated fetal weight at fetal surgery, or fetal lesion level. Of the 86 patients, 64 underwent primary linear repair and 22 underwent bipedicle flap repair. There were no significant differences in rates of intrauterine fetal demise, postnatal mortality, midline repair site dehiscence, or the need for CSF diversion by final follow-up. Operative times were longer (32.5 vs 18.7 minutes, p < 0.001) and gestational age at delivery was lower (232 vs 241 days, p = 0.01) in the bipedicle flap cohort, but long-term functional outcomes were not different.

CONCLUSIONS

Analysis of the total cohort affirms the long-term benefits of fetal myelomeningocele repair. In utero bipedicle flaps are safe and can be used for high-tension lesions without increasing perioperative risks to the mother or fetus. In utero flaps preserve the long-term benefits seen with primary linear repair and may expand inclusion criteria for fetal repair, providing life-changing care for more patients.

Primary vs patch-based skin closure for in-utero spina bifida repair

OBJECTIVE

During in-utero spina bifida (SB) repair, closure of large defects is often challenging, requiring tissue graft for watertight skin closure. No prior studies have compared primary skin closure vs patch-based repair. Our objective was to compare neonatal and 1-year outcomes associated with these two types of skin closure for in-utero SB repair.

METHODS

This was a prospective cohort study of 102 patients undergoing open prenatal SB repair from September 2011 to August 2021 at a single institution. All patients met the inclusion criteria of the Management of Myelomeningocele Study (MOMS), and the surgical procedure for in-utero SB repair was similar to that described in the MOMS trial. During the surgery, if primary skin approximation was not feasible due to the large size of the defect, the decision was at the discretion of the pediatric neurosurgeon to utilize a patch for closure. Neonatal outcomes at birth and 1-year outcomes were compared between the primary skin and patch-based closure groups.

RESULTS

Of 102 patients included in the study, 70 (68.6%) underwent primary skin closure and 32 (31.4%) patch-based closure. The patch type included acellular bovine skin matrix (Durepair®; n = 31) and human acellular dermal matrix (Alloderm®; n = 1). Fetuses with myeloschisis were more likely to require patch-based repair than those with myelomeningocele. The median time of fetal repair was 4 min longer for patch-based compared with primary skin closure (37 vs 33 min; P = 0.001). Following patch-based repair, neonates had a longer length of stay in the neonatal intensive care unit (NICU) by 24 days (adjusted risk ratio, 2.40 (95% CI, 1.41-4.29)) compared to those that underwent primary skin closure. There was no difference between the two groups in the other neonatal outcomes, including the need for ventriculoperitoneal shunt placement and cerebrospinal fluid leakage. Outcome at 1 year of age was available for 90 infants. Need for wound revision within their first year after birth was more common in infants who underwent patch-based vs those with primary skin closure (19.4% vs 5.1%; P = 0.05). There was no difference between the two groups in other 1-year outcomes, including the need for ventriculoperitoneal shunt placement by 1 year of age and surgery for tethered cord.

CONCLUSIONS

Patch-based closure during SB repair is often needed in fetuses with myeloschisis and is associated with prolonged fetal surgery time, long NICU stay and need for wound revision within the first year after birth. Further studies are required to identify optimal patches for SB repair or alternative methods to improve outcome. © 2022 International Society of Ultrasound in Obstetrics and Gynecology.

Human fetal skin derived merkel cells display distinctive characteristics in vitro and in bio-engineered skin substitutes in vivo

Human skin contains specialized neuroendocrine Merkel cells responsible for fine touch sensation. In the present study, we performed in-depth analysis of Merkel cells in human fetal back skin. We revealed that these Merkel cells expressed cytokeratin 20 (CK20), were positive for the neuroendocrine markers synaptophysin and chromogranin A, and the mechanosensitive ion channel Piezo2. Further, we demonstrated that Merkel cells were present in freshly isolated human fetal epidermal cells in vitro, and in tissue-engineered human dermo-epidermal skin substitutes 4 weeks after transplantation on immune-compromised rats. Merkel cells retained the expression of CK20, synaptophysin, chromogranin A, and Piezo2 after isolation and in culture, and in the skin substitutes after transplantation. Interestingly, we observed that in fetal skin and in skin substitutes, only Merkel cells were positive for CK8, while in culture, also non-Merkel cells showed positivity for CK8. In summary, human fetal Merkel cells showed phenotypical features confirming their cell identity. This findings are of pivotal importance for the future application of fetal tissue-engineered skin in clinics.

The Keystone Island Perforator Flap in Reconstruction of Large Myelomeningocele Defects

BACKGROUND

Reconstruction of the skin defect after myelomeningocele repair is a crucial step that influences the quality of the surgical outcome. Keystone perforator flap is an islanded fasciocutaneous flap based on random regional perforators, which is advanced to adjacent defects. It has become a reliable method of locoregional reconstruction in various body parts with minimum morbidity. The aim of this study was to evaluate our clinical experiences in using keystone perforator flaps as an alternative surgical method for closure of large myelomeningocele defects.

METHODS

In this study, the keystone island perforator flap was used for reconstruction of large myelomeningocele defect in 7 patients (5 males and 2 females) aged between 7 days and 4.5 months. The defect size was 5.9 cm × 6.5 cm on average (range, 4.5 × 5 cm to 7 × 9 cm). The localization of the lesions was lumbosacral in 6 patients and thoracolumbar in 1 patient.

RESULTS

In all patients, tension-free closure was obtained and healing was successful without any complications, except 1 infection, which resolved with conservative wound management. There was no patient with late breakdown of the wound or associated cerebrospinal fluids fistula formation for a mean of 13 months (range, 4 months to 2 years).

CONCLUSIONS

The keystone perforator flap technique is an effective, reliable, and durable reconstructive option which enables the reconstructive surgeon to attain a tension-free closure of sizable meningomyeleocele defects with no late wound breakdown or associated cerebrospinal fluids fistula formation and negligible donor site morbidity.

Open fetal myelomeningocele repair at a university hospital: surgery and pregnancy outcomes

PURPOSE

Myelomeningocele (MMC) is an open neural tube defect that causes great morbidity. Prenatal open repair is the standard treatment; however, there are many complications related to the procedure. This study reports preliminary findings of open in utero repair of MMC in a public tertiary hospital in Brazil and describes factors that could be associated with increased surgical morbidity.

METHODS

Thirty-nine patients underwent open in utero repair of MMC from October 2015 to August 2019. The Clavien-Dindo classification of surgical complications and a classification system with the preterm definitions of the World Health Organization were used, respectively, for maternal and fetal complications.

RESULTS

A total of 28 mothers (71.8%) and 31 fetuses (79.5%) experienced at least one minor to major complication. Three mothers (7.7%) had a severe grade 4 complication. Fetal complications grades 3 to 5 occurred in 13 fetuses (33.3%). Gestational age at surgery and at birth were 24.88 ± 1.16 weeks and 33.23 ± 3.68 weeks, respectively. Preterm delivery occurred in 30 patients (76.9%), membrane rupture in 18 patients (46.2%) and chorioamnionitis in 13 patients (33.3%).

CONCLUSION

Open fetal surgery for MMC was performed at a Brazilian public tertiary care center, resulting in three grade 4 maternal complications. Relevant fetal complications were also present. The use of a standard classification system for complications renders studies more comparable and data more useful for counseling patients. Adjustments of perioperative procedures and long-term follow-up are needed to determine the real benefit of open in utero repair of MMC at our hospital.

Impact of the size of the lesion in prenatal neural tube defect repair on imaging, neurosurgical and motor outcomes: a retrospective cohort study

OBJECTIVES

(1) To compare brain findings between large and non-large neural tube defect (NTD); (2) to evaluate the impact of large lesion on the surgical parameters; (3) to study any associations between the size of the lesions and brain findings 6 weeks postoperatively and neurological short-term outcomes.

DESIGN

Retrospective cohort study.

SETTING

Texas Children's Hospital, between 2011 and 2018.

POPULATION

Patients who underwent prenatal NTD repair.

METHODS

Large lesion was defined when the lesion's surface was >75th centile of our cohorts' lesions.

MAIN OUTCOME MEASURES

Time of referral: ventriculomegaly and anatomical level of the lesion; surgery: duration and need for relaxing incisions. 6 weeks postoperative: hindbrain herniation (HBH) and ventriculomegaly. After delivery: dehiscence, need for hydrocephalus treatment and motor function.

RESULTS

A total of 99 patients were included, 25 of whom presented with large lesions. Type of lesion and ventriculomegaly were comparable between individuals with large and non-large lesions. Individuals with large lesions were associated with increased need for relaxing incisions by 5.4 times (95% CI 1.3-23.2, P = 0.02). Six weeks postoperatively, having a large lesion decreased by ten times the likelihood of having a postoperative reversal of HBH (odds ratio = 0.1, 95% CI 0.1-0.4, P < 0.01). At birth, larger lesions increased the risk for repair dehiscence by 6.1 times (95% CI 1.6-22.5, P < 0.01) and the risk of dehiscence or leakage of cerebrospinal fluid at birth by 5.5 times (95% CI 1.6-18.9, P < 0.01).

CONCLUSION

Prenatal repair of patients with large NTD presents a lower proportion of HBH reversal 6 weeks after the surgery, a higher risk of dehiscence and a higher need for postnatal repair.

TWEETABLE ABSTRACT

Evaluation of the size of fetal NTD can predict adverse neurological outcomes after prenatal NTD repair.

Bioengineering and in utero transplantation of fetal skin in the sheep model: A crucial step towards clinical application in human fetal spina bifida repair

An intricate problem during open human fetal surgery for spina bifida regards back skin closure, particularly in those cases where the skin defect is much too large for primary closure. We hypothesize that tissue engineering of fetal skin might provide an adequate autologous skin substitute for in utero application in such situations. Eight sheep fetuses of four time-mated ewes underwent fetoscopic skin biopsy at 65 days of gestation. Fibroblasts and keratinocytes isolated from the biopsy were used to create fetal dermo-epidermal skin substitutes. These were transplanted on the fetuses by open fetal surgery at 90 days of gestation on skin defects (excisional wounds) created during the same procedure. Pregnancy was allowed to continue until euthanasia at 120 days of gestation. The graft area was analyzed macroscopically and microscopically. The transplanted fetal dermo-epidermal skin substitutes was well discernable in situ in three of the four fetuses available for analysis. Histology confirmed healed grafts with a close to natural histological skin architecture four weeks after in utero transplantation. This experimental study generates evidence that laboratory grown autologous fetal skin analogues can successfully be transplanted in utero. These results have clinical implications as an analogous procedure might be applied in human fetuses undergoing prenatal repair to facilitate primary skin closure. Finally, this study may also fertilize the field of fetal tissue engineering in general, particularly when more interventional, minimally invasive, and open fetal surgical procedures become available.

An Unreported Complication After Fetoscopic Myelomeningocele Closure

Myelomeningocele (MMC) is a type of open neural tube defect characterized by exposure of the spinal cord through a defect in the skin and posterior hindbrain herniation through the foramen magnum. Outcomes vary but common morbidities include paraplegia, hydrocephalus, neurogenic bladder, scoliosis, and tethered cord. Fetal surgery, although not a cure, has been shown to decrease the risk of associated morbidity.A study of a neonate born at 39 5/7 weeks gestation status-post in utero fetoscopic MMC repair at 24 weeks gestation was presented in this study along with a concise review of the literature. Fasciocutaneous advancement flaps were made in utero to facilitate a tension-free midline closure and were left to heal secondarily. The neonate underwent uncomplicated spontaneous vaginal delivery but was noted to have a right flank hernia through the relaxing incision in addition to delayed healing of the left relaxing incision. According to authors, iatrogenic flank hernia following fetoscopic MMC repair has not been previously reported in the literature. Both defects were repaired primarily in layers with undermining and retroperitoneal domain was reestablished with imbrication of the overlying muscle on the right side. The authors report their experience to contribute to the scarce literature describing postnatal complications arising from this novel procedure.

Percutaneous fetoscopic closure of large open spina bifida using a bilaminar skin substitute

OBJECTIVE

We have described previously our percutaneous fetoscopic technique for the treatment of open spina bifida (OSB). However, approximately 20-30% of OSB defects are too large to allow primary skin closure. Here we describe a modification of our standard technique using a bilaminar skin substitute to allow closure of large spinal defects. The aim of this study was to report our clinical experience with the use of a bilaminar skin substitute and a percutaneous fetoscopic technique for the prenatal closure of large OSB defects.

METHODS

Surgery was performed between 24.0 and 28.9 gestational weeks with the woman under general anesthesia, using an entirely percutaneous fetoscopic approach with partial carbon dioxide insufflation of the uterine cavity, as described previously. If there was enough skin to be sutured in the midline, only a biocellulose patch was placed over the placode (single-patch group). In cases in which skin approximation was not possible, a bilaminar skin substitute (two layers: one silicone and one dermal matrix) was placed over the biocellulose patch and sutured to the skin edges (two-patch group). The surgical site was assessed at birth, and long-term follow-up was carried out.

RESULTS

Percutaneous fetoscopic OSB repair was attempted in 47 consecutive fetuses, but surgery could not be completed in two. Preterm prelabor rupture of membranes (PPROM) occurred in 36 of the 45 (80%) cases which formed the study group, and the mean gestational age at delivery was 32.8 ± 2.5 weeks. A bilaminar skin substitute was required in 13/45 (29%) cases; in the remaining 32 cases, direct skin-to-skin suture was feasible. There were 12 cases of myeloschisis, of which 10 were in the two-patch group. In all cases, the skin substitute was located at the surgical site at birth. In five of the 13 (38.5%) cases in the two-patch group, additional postnatal repair was needed. In the remaining cases, the silicone layer detached spontaneously from the dermal matrix (on average, 25 days after birth), and the lesion healed by secondary intention. The mean operating time was 193 (range, 83-450) min; it was significantly longer in cases requiring the bilaminar skin substitute (additional 42 min on average), although the two-patch group had similar PPROM rate and gestational age at delivery compared with the single-patch group. Complete reversal of hindbrain herniation occurred in 68% of the 28 single-patch cases and 33% of the 12 two-patch cases with this information available (P < 0.05). In four cases there was no reversal; half of these occurred in myeloschisis cases.

CONCLUSIONS

Large OSB defects may be treated successfully in utero using a bilaminar skin substitute over a biocellulose patch through an entirely percutaneous approach. Although the operating time is longer, surgical outcome is similar to that in cases closed primarily. Cases with myeloschisis seem to have a worse prognosis than do those with myelomeningocele. PPROM and preterm birth continue to be a challenge. Further experience is needed to assess the risks and benefits of this technique for the management of large OSB defects. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

Successful grafting of tissue-engineered fetal skin

PURPOSE

Fetal repair of spina bifida results in improved outcomes and has therefore become a standard clinical procedure in some highly specialized centers. However, optimization of the procedure technique and timing is needed. Both might be achieved by facilitating the procedure using laboratory-grown fetal skin substitutes. The aim of this study was therefore to test in vivo the suitability of such a fetal skin substitute for an in utero application.

METHODS

Collagen-based hydrogels containing fetal ovine fibroblasts were seeded with fetal ovine keratinocytes and transplanted on immuno-incompetent nu/nu rats. After 3 weeks, grafts were harvested and analyzed histologically and by immunohistochemistry.

RESULTS

Laboratory-grown fetal ovine dermo-epidermal skin substitutes showed successful engraftment at 3 weeks. Histologically, grafts revealed a neo-dermis populated by fibroblasts and with ingrowth of vessels, and an epidermis with an adult-like, mature appearance depicting clearly basal, spinous, granular, and a corneal layer. Immunostaining confirmed a physiologically organized epidermis.

CONCLUSION

Fetal dermo-epidermal skin substitutes of ovine origin can successfully be grafted in vivo. In a next step, we will have to test whether favorable results can also be obtained when grafts are used in utero. If so, then human fetal spina bifida repair using laboratory-grown autologous fetal skin for defect closure may be envisaged.

A decision-making guide for the closure of myelomeningocele skin defects with or without primary repair

OBJECTIVE The closure of the skin defect in myelomeningocele (MMC) repair is an essential step that determines the quality of the surgical result. The success of surgical results is related to the decision to use the most suitable techniques, namely flaps or primary closure. The aim of this study was to evaluate the effectiveness of a decision-making guide to determine whether to use primary repair or a flap for the closure of skin defects that occur in MMC. METHODS Fifty patients underwent surgery after neurosurgical repair and closure of the placode. A simple guide was generated according to the defect height/width and posterior axillary lines/defect width ratio. These 2 ratios were considered to determine which closure technique (with or without primary repair) should be used for the MMC defect reconstruction. RESULTS By using this decision-making guide, 20 of the defects were repaired with various flaps, and those of the remaining 30 patients were repaired with primary closure. In all patients, a successful tension-free 1-stage closure was obtained. Except for 4 patients who had flap reconstruction with partial flap necrosis or minimal flap tip necrosis, healing was uneventful without any complications. There were no additional wound complications during the mean follow-up of 6.8 years (range 5 months to 14 years). CONCLUSIONS Because of various defect sizes and patient characteristics, no single protocol exists for the reconstruction of MMC defects. The guide suggested here might be effective in deciding which method is suitable for closure of MMC skin defects.

The reading man flap for closure of large meningomyelocele defects

BACKGROUND

Closure of the skin defect in myelomeningocele repair is an essential step that determines the quality of the surgical result. In large myelomeningoceles, however, adequate skin coverage may not be accomplished by direct closure or skin undermining. In such cases, the skin defect is best repaired using flaps. The aim of this study is to evaluate the reading man procedure for closure of large meningomyelocele defect.

METHODS

In this procedure, after neurosurgical repair and closure of the placode, the defect surgically becomes a circle in shape. Then, the circular defect is closed by transposition of two skin flaps designed in an unequal Z-plasty manner. Over 5 years, the reading man procedure was used for closure of large meningomyelocele defects in seven patients (four females and three males), aged between 1.5 and 6 months. The defect size was 10.5×7.25 cm (8.5×5.3 and 12.6×9.5 cm) on average. The localisation of the lesions was thoracolumbar in two patients and lumbosacral in five patients.

RESULTS

In all patients, a successful tension-free one-stage closure was obtained without dog-ear formation. Except for one patient with minimal tip necrosis, healing was uneventful without any complications. There was no patient with late breakdown of the wound during 1.5 years (8 months-4 years) of mean follow-up.

CONCLUSIONS

The reading man procedure enables the surgeon to achieve a tension-free defect closure of considerably large meningomyeleocele defects. Using two well-vascularised fasciocutaneous flaps, it provides a durable coverage and soft tissue padding over the neural tissues with no suture seam at midline. With these advantages, the Reading Man Procedure seems to be a useful and safe alternative for closure of large meningomyelocele defects.

Foetal surgery and cleft lip and palate: current status and new perspectives

Now-a-days, high-resolution ultrasound allows an accurate and relatively early diagnosis of congenital malformations. In a limited number of such conditions foetal surgery may be lifesaving. However, premature labour has been the major drawback for open foetal surgery. Recently, improvement of video-endoscopic technology has boosted the development of operative techniques for feto-endoscopic surgery, which has been demonstrated to be less invasive than the open approach. Main clinical application of fetoscopic procedures today is the treatment of feto-foetal transfusion syndrome. Although still in development, feto-endoscopic surgery seems to offer new hope for surgical foetal therapy not only in cases of life threatening conditions. Experimental intrauterine correction of cleft lip and palate (CLP) has been lately performed using the feto-endoscopic approach. This procedure offers two major advantages: first, scarless foetal wound healing and bone healing without callus formation, which would also allow a better/normal maxillary growth, and second, significant decrease of foetal and maternal morbidity. Herein, we report the current status of experimental and clinical foetal surgery and propose possible directions for continuing research to make intrauterine procedures safer. Furthermore, we discuss current knowledge and new perspectives of experimental foetal cleft lip and palate repair, which in the future may lead to such excellent results in the operative treatment of clefts, that less or no secondary corrections and therapies, such as orthodontic, dental, logopedic, etc. would be needed. Only if these conditions can be fulfilled, will we be able to improve substantially our therapy for the human foetus with a cleft lip and palate. In spite of all efforts, however, it must be considered that it may not ever be possible to find the optimal treatment method for this or other craniofacial malformations.

Soft tissue closure and plastic surgical aspects of large dorsal myelomeningocele defects (review of techniques)

The large myelomeningocele defects that cannot be closed reliably by simple skin undermining require a close cooperation between the neurosurgeon and the plastic surgeon. In this study, a 3-year review was undertaken of nine consecutive patients with a myelomeningocele defect treated in our hospital. The aim of the study was to analyze the size, location of myelomeningocele defects, features of the surrounding tissue, and type and results of the reconstruction method for skin closure. Of the nine patients, five were repaired within the first 48 h of life, two within the 1st month of life, and two were repaired within the 1st year of life. Of the nine patients, seven (78%) underwent repair with direct skin approximation by the Neurosurgical Service. For three patients (33%) with large lumbosacral meningomyelocele defects, including one patient who had failed direct skin approximation, the Plastic Surgery Service achieved the skin closure by bilateral paralumbar fasciocutaneous rotational flaps. Minimal area in the patients referred to the Plastic Surgery Service was 24 cm2 (range 24-48 cm2); patients having 18 cm2 or less skin defect were not referred for closure. In conclusion, fasciocutaneous rotational flaps provided tension-free, durable, innervated and well-vascularized skin coverage over the dural repair in all three referred patients, without using skin graft. Since myelomeningocele defects vary in size, shape, and location, no single procedure applies to all. Therefore, other reconstruction methods involving skin grafts, fasciocutaneous flaps, and musculocutaneous flaps are reviewed in this report.

Intrauterine repair of spina bifida: preoperative predictors of shunt-dependent hydrocephalus

OBJECTIVE

The objective of this study was to determine which factors that are present at the time of intrauterine repair of spina bifida could predict the need for ventriculoperitoneal shunt for hydrocephalus during the first year of life.

STUDY DESIGN

One hundred seventy-eight fetuses have undergone intrauterine repair of spina bifida at Vanderbilt University Medical Center since 1997. Among these, 116 fetuses had a postnatal follow-up period of at least 12 months. The primary outcome of the study was the need for a ventriculoperitoneal shunt for hydrocephalus during the first year of life. The following variables were analyzed: maternal demographics (age, race, gravidity, and parity), gestational age at the time of surgery, ventricular size, degree of hindbrain herniation (determined by magnetic resonance imaging in 33 cases), type of defect (myelomeningocele vs myeloschisis), upper level of the lesion, presence of talipes, and intraoperative use of a lumbar drain. Statistical analysis was performed with logistic regression (to test the association of fetal and maternal factors and the need for ventriculoperitoneal shunting), 2-sample t-tests for comparison of means, and receiver operating curves with the use of the probabilities that were generated by the logistic regression for both continuous and categoric versions of the factors.

RESULTS

Sixty-one of 116 of the fetuses (54%) who underwent operation in utero required the placement of a ventriculoperitoneal shunt before the age of 1 year. The upper level of the lesion was the strongest predictor of shunt requirement (adjusted odds ratio per 1 level increase with the use of continuous variables [S1 through T10], 1.73 [95% CI, 1.22- 2.44]; adjusted odds ratio with the use of upper lesion level >or=L3 vs <L3 as a categorized variable, 5.7 [95% CI, 2.18- 14.7]), followed by gestational age at the time of surgery (adjusted odds ratio per 1 week increase with the use of continuous variables, 1.37 [95% CI, 1.06-1.77]; adjusted odds ratio with the use of gestational age <or=25 weeks vs >25 weeks as a categorized variable, 3.3 [95% CI, 1.28-8.24]), and preoperative ventricular size (adjusted odds ratio per 1 unit increase with the use of continuous variables, 1.17 [95% CI, 1.01-1.36]; adjusted odds ratio with the use of ventricular size >or=14 mm vs <14 mm as a categorized variable, 3.5 [95% CI, 1.08-11.16]). Receiver operating curves with the use of the probabilities that were generated by the logistic regression analyses for both the continuous and categoric versions of the factors were compared. The area under the curve was approximately 0.81 for both methods. Thirty-eight of 48 of the fetuses (79%) with an upper level of the lesion >or=L3 required placement of a ventriculoperitoneal shunt, although 25 of 68 of the fetuses (37%) with lesions <or=L4 did not (P < .0001). Eighty-four percent of the fetuses with a preoperative ventricular size >or=14 mm (27/32 fetuses) needed a shunt compared with 41% of the fetuses (34/81 fetuses) with smaller ventricles (P=.03). Seventy-one percent of the fetuses who underwent operation at >25 weeks of gestation also required shunt placement (37/52 fetuses); 39% of the fetuses (24/61 fetuses) who were treated <or=25 weeks of gestation did not (P=.01). Thirty-five fetuses had a lesion level <or=L4 and a ventricular size <14 mm and underwent operation at <or=25 weeks of gestation. Among these, 8 fetuses (23%) required a ventriculoperitoneal shunt during the first year of life.

CONCLUSION

This study suggests that, among fetuses who underwent operation in utero for spina bifida, fetuses with a ventricular size of <14 mm at the time of surgery, fetuses who had surgery at <or=25 weeks of gestation, and fetuses with defects that were located at <or=L4 were less likely to require ventriculoperitoneal shunting for hydrocephalus during the first year of life.

Skin graft on the surgically induced spinal open neural tube defects does not induce lipomatous malformation but enhances re-closure to the normal state in chick embryos

To determine the effect of skin allograft on open neural tube defects (ONTDs), the neural tube was incised open using Hamburger and Hamilton stage 18 or 19 chick embryos for a length of six somites. Embryos were divided into two groups: graft and control (with and without skin allograft). On postoperative day 5, closure of ONTDs was more frequent in the graft group than in the control group (9/15 versus 0/15), and healing was nearly complete. However, typical lipomatous features were not observed. These results suggest that simple mechanical attachment of skin allograft on ONTDs does not lead to lipomatous malformation in chick embryos. On the other hand, our results support a potential role of skin allograft in the management of prenatal spinal ONTDs.