Anal canal duplication in children: a monocentric experience of 12 cases.

PURPOSE: Anal canal duplication is a rare malformation characterized by a second perineal opening positioned behind the anus, which is generally observed at 6 o'clock in the lithotomy position. The purpose was to describe six new cases of anal canal duplication (in addition to our previously reported series of six patients) with the aim of providing further clinical information about this anomaly. METHODS: We described 6 new cases of anal canal duplication in terms of symptoms, anatomical disposition, imaging results, and histopathology. Clinical details of these cases and those already reported (n = 12) were summarized and compared to existing literature. RESULTS: A total of 12 cases were reported over 34 years. 17% of the patients were male, constituting the only subgroup to present a communication with the digestive tract. A single patient, diagnosed at 12 years, was symptomatic. Half of the patients had at least one associated malformation. All patients underwent surgery, either with a posterior sagittal or perineal approach. CONCLUSION: Diagnosis of anal canal duplication should be suspected when a perineal opening positioned behind the anus is present, and necessitates further exploration by a comprehensive clinical examination and imaging. Surgery is always required, typically performed via a posterior sagittal approach. The postoperative course is usually uncomplicated.

Synchrotron phase-contrast imaging applied to the anatomical study of the hand and its vascularization.

Microscopic anatomical study of the hand requires difficult or destructive dissection techniques for each anatomical structure. Synchrotron phase-contrast imaging (sPCI) allows us to study precisely, at a microscopic resolution and in a nondestructive approach, the soft tissues and bone structures within a single 3D image. Therefore, we aimed to assess the capacity of sPCI to study the arterial anatomy of the hand and digits in human cadavers for anatomical purposes. A non-injected hand from an embalmed body was imaged using sPCI at 21-µm pixel size. The vascularization and innervation of the hands were virtually reconstructed at 84-µm resolution, and the medial neurovascular bundle of the third digit at 21 µm. The thinner-most distal structures were observed and reported. The diameter and thickness of the vascular and neural structures were defined on 2D computed tomographic axial projections, and using a granulometry method coupled to the 3D reconstructions. The vascularization of the hand was visible from the radial and ulnar arteries to the distal digital transverse anastomoses. The thinnest structure observed was the anastomotic arterial network around the proper palmar digital nerve. The latter emerged from the proper palmar digital artery and vascularized the nerve around its whole length and circumference. The perineural arterioles individualizable at this resolution had a diameter of 66-309 µm. In conclusion, sPCI allows both the arterial and neural anatomy of the hand to be studied at the same time, as well as the anatomical interactions between both networks. It facilitates the study of structures that have different sizes, diameters, thickness, and histological origin with great precision, in a noninvasive way, and using a single technique.

Study of abdominal wall muscle innervation applied to large-defect closure in congenital diaphragmatic hernia.

In large congenital diaphragmatic hernias (CDHs), direct suture of the diaphragm is impossible. Surgeons can use a triangular internal oblique muscle (IOM) plus transverse abdominis muscle (TAM) flap. Its caudal limit faces the medial extremity of the 11th rib. Clinical studies show that the flap is not hypotonic but that the procedure could expose patients already presenting a hypoplastic lung to external oblique muscle (EOM) hypotonia. The aims of this study were to study EOM innervation by the 10th intercostal nerve (ICN) and ICN innervation to the IOM and TAM. Forty cadaveric abdominal hemi-walls were dissected. The number of branches and the trajectory of each specimen's 10th ICN were studied medially to the medial extremity of the 11th rib (MEK11) using surgical goggles and a microscope (Carl Zeiss®). The 10th ICN was consistently found between the IOM and TAM. There was a median of nine branches from the 10th ICN to the EOM, 77% of them medial to the MEK11. Median values of nine and 12 branches for the IOM and TAM were found, 60% and 51%, respectively, medial to the MEK11. These results argue in favor of good innervation to the IOM plus TAM flap but also indicate postoperative abdominal weakness exposing patients to herniation risks, as more than 75% of the branches from the 10th ICN to the EOM were sectioned or pulled away during flap detachment. Clin. Anat., 33:759-766, 2020. © 2019 Wiley Periodicals, Inc.