Malrotation is typically diagnosed during the evaluation of bilious vomiting or abdominal pain, which are symptoms associated with complications such as midgut volvulus or bowel obstruction during the first year of life [1]. The estimated incidence of this condition is 1 in 500 births [2], but the true incidence is difficult to determine because some patients may remain asymptomatic throughout their lives. To date, only a few cases of prenatally diagnosed asymptomatic malrotation have been reported (Table 1) [3,4,5,6]. Cassart et al. [3] reported two cases of malrotation suspected on prenatal ultrasound based on medially positioned stomachs, which were confirmed postnatally. Biyyam et al. [4] described a case in which malrotation was suspected based on the finding of a midline stomach on fetal ultrasound and was confirmed by fetal MRI. Lesieur et al. [5] reported a fetus with dilated bowel loops in the left abdomen on prenatal ultrasound, and subsequent MRI confirmed the diagnosis of malrotation without volvulus. Zulli et al. [6] detailed a case in which fetal ultrasound showed a misplaced colon in the left abdomen and inversion of mesenteric vessels, with MRI confirming the diagnosis of malrotation. In our case, fetal MRI performed for another reason incidentally revealed the abnormal position of the intestine, leading to the diagnosis of malrotation without volvulus by contrast study after birth.

While the results of ultrasonography can be influenced by the operator’s skill and experience, MRI provides a more objective evaluation. Blask et al. [7] retrospectively evaluated cases of malrotation without obstruction that were confirmed by either imaging or surgery. They concluded that non-rotation of the bowel can indeed be detected using fetal MRI. Given the incidence of malrotation, which is approximately 1 in 500 births [2], it is likely that the prenatal diagnosis of isolated malrotation without midgut volvulus may become more common in the future.

Malrotation itself is not a life-threatening condition; however, when complicated by midgut volvulus, the situation becomes critical. Midgut volvulus can block blood flow to the intestine at the base of the superior mesenteric artery and vein, leading to ischemia of a significant portion of the intestine. If diagnosis is delayed, the resulting damage to the intestine can become irreversible, necessitating massive intestinal resection. This can lead to life-threatening conditions or result in short bowel syndrome. Therefore, prompt surgical intervention for symptomatic malrotation has gained widespread consensus as the appropriate treatment approach.

However, the treatment of asymptomatic malrotation remains controversial [8]. Given the potential risks associated with this condition, early diagnosis and treatment before the onset of symptoms related to midgut volvulus are ideal. Kedoin et al. [1] conducted a retrospective chart review of malrotation cases and found that 71.3% (57/80) of the cases involved neonates. Among these 57 neonates, midgut volvulus was observed in 41 and bowel resection was required in 4. Notably, in two of these four neonates, the torsion was only 180 degrees, highlighting that even mild volvulus can lead to critical intestinal ischemia in neonates. Additionally, 20 neonates (40.4%) did not present with bilious vomiting, illustrating the challenges in diagnosing symptomatic malrotation [1]. Malek et al. [9] used the data from the Nationwide Inpatient Sample and evaluated the role of the Ladd’s procedure in patients with asymptomatic malrotation. They reported that the gain in quality adjusted life expectancy associated with a prophylactic Ladd's procedure was highest when asymptomatic malrotation was treated at 1 year old and steadily declined until asymptomatic malrotation was treated at 20 years old. Covey et al. [10] compared pediatric patients who underwent a prophylactic Ladd procedure before any malrotation-related symptoms occurred (n = 19) with those who underwent the procedure after the onset of symptoms (n = 23). They found that the reoperation rate was significantly higher in the latter group, leading to the conclusion that prophylactic Ladd procedures are both safe and recommended [10]. However, when considering surgery, it is important to weigh the risks of postoperative complications, such as intestinal obstruction due to adhesions. Long-term follow-up studies have shown that postoperative complications are common in children with intestinal malrotation who undergo surgery [11, 12]. Mitsunaga et al. [12] reported that intestinal obstruction occurred in 22 of 87 cases (25.3%) following conventional open Ladd procedures.

A systematic review by the APSA Outcomes and Evidence-Based Practice Committee indicated that surgery may be considered for younger asymptomatic patients, whereas observation might be more appropriate for older asymptomatic patients [8]. Some reports suggest that the treatment strategy should be tailored according to the type of malrotation [5, 6]. Zulli et al. [6] argued that complete non-rotation can be managed conservatively because the mesenteric stalk is wide and the risk of volvulus is low. Conversely, incomplete rotation should be corrected to the position of non-rotation due to the narrow mesenteric root, which places the intestine at a significant risk of volvulus [6]. Lesieur et al. [5] emphasized that if a rotational disorder is suspected, it is crucial to eliminate incomplete rotation and assess the length of the mesenteric root by evaluating the positions of the angle of Treitz and the cecum. In our case, the contrast enema revealed that the cecum was located in the right-upper abdomen, and the mesenteric base was suspected to be narrow, indicating a high risk of midgut volvulus. We thoroughly explained to the parents the advantages and disadvantages of both surgery and observation. After considering the information provided, the parents opted for surgical intervention. In this case, the parents had been informed of the possibility of malrotation by the obstetrician in charge before the birth, so when we discussed the treatment about the patient, they could listen to our explanation calmly and make their decision smoothly.

The operation for malrotation was first described by Ladd [13] in 1936, and it has since become the gold standard surgical technique for this condition. The procedure involves detorsion of the volvulus, if present; division of the abnormal band between the cecum and duodenum (Ladd’s band); widening of the mesenteric root; and repositioning the intestine in a “non-rotation” position. The laparoscopic approach for treating malrotation was first reported by van der Zee [14] in 1995. Although the laparoscopic approach has gained favor because of better cosmetic outcomes, faster progression to full feeding, and shorter hospital stays, controversy remains regarding its efficacy, completeness, and the optimal patient population for this minimally invasive technique [15,16,17,18,19].

Compared with the open approach, the laparoscopic Ladd procedure generally has a lower rate of bowel obstruction but a higher rate of reoperation for re-volvulus. Zhu et al. [20] reported that the rate of postoperative re-volvulus is significantly higher following laparoscopic surgery than open surgery. However, Arnaud et al. [21] found that the rate of redo surgery was similar between the laparoscopic and open approaches. Reddy et al. [22] highlighted that the most frequent finding at reoperation was inadequate straightening of the duodenum, often attributed to poor visualization and local bleeding during the initial laparoscopic procedure.

Another issue with the laparoscopic approach is the high conversion rate to open surgery. Most children with this condition present with symptoms and undergo surgery within the first year of life, making the laparoscopic procedure technically challenging and requiring a high level of surgical skill. Consequently, the conversion rate to open surgery is relatively high. Miyano et al. [23] reported that the laparoscopic Ladd procedure cannot be recommended for the treatment of malrotation in neonates. By contrast, Xie et al. [24] compared the laparoscopic Ladd procedure with the open approach and concluded that the former is a safe option, even in infants and neonates, provided it is performed at a center with expertise in laparoscopic surgery. Arnaud et al. [21] also noted that conversions from laparoscopic to open surgery occurred more frequently during the early stages of a surgeon’s experience and emphasized that the procedure should be performed by an expert. In our case, malrotation was suspected prenatally, and the diagnosis was confirmed early, before the occurrence of volvulus. The operation was performed as scheduled, allowing for excellent laparoscopic visualization. The intestines were neither dilated nor edematous, which facilitated the safe dissection of Ladd’s ligament and sufficient widening of the mesentery. We believe that the laparoscopic Ladd procedure can be performed safely, even in neonates, under elective circumstances where midgut volvulus is not complicated.