Anatomical reconsideration to renal area: lessons learned from radical nephrectomy or adrenalectomy through a minimal incision over the 12th rib

The Development of an Automatic Rib Sequence Labeling System on Axial Computed Tomography Images with 3-Dimensional Region Growing

This paper proposes a development of automatic rib sequence labeling systems on chest computed tomography (CT) images with two suggested methods and three-dimensional (3D) region growing. In clinical practice, radiologists usually define anatomical terms of location depending on the rib’s number. Thus, with the manual process of labeling 12 pairs of ribs and counting their sequence, it is necessary to refer to the annotations every time the radiologists read chest CT. However, the process is tedious, repetitive, and time-consuming as the demand for chest CT-based medical readings has increased. To handle the task efficiently, we proposed an automatic rib sequence labeling system and implemented comparison analysis on two methods. With 50 collected chest CT images, we implemented intensity-based image processing (IIP) and a convolutional neural network (CNN) for rib segmentation on this system. Additionally, three-dimensional (3D) region growing was used to classify each rib’s label and put in a sequence label. The IIP-based method reported a 92.0% and the CNN-based method reported a 98.0% success rate, which is the rate of labeling appropriate rib sequences over whole pairs (1st to 12th) for all slices. We hope for the applicability thereof in clinical diagnostic environments by this method-efficient automatic rib sequence labeling system.

Experience in the application of laparoscopic anatomical adrenalectomy via the renal cortex surface monolayer

Objective:

To discuss the clinical application of laparoscopic anatomical adrenalectomy via the renal cortex surface in the operation of adrenal masses.

Methods:

A retrospective analysis was performed on 231 patients with adrenal masses who were received and cured in the urology department of the Affiliated Hospital of Hebei University from July 2016 to January 2019. All patients received retroperitoneal adrenalectomy by means of laparoscopic anatomical adrenalectomy via the renal cortex surface. Operation duration, bleeding volume, postoperative complications, retention time of the drainage tube were measured and analyzed, and postoperative follow-up surveys were administered.

Results:

All cases were successfully operated. Two cases were converted to open surgery due to the presence of large adrenal tumors, and the patients suffered no significant complications. The mean operation duration, bleeding volume and retention time of the drainage tube were 31 minutes, 20 mL and 1.2±0.6 d, respectively. In terms of the postoperative pathology of adrenal tumors, 183 cases were shown to have adenomas, 34 had pheochromocytomas, nine had schwannomas, 3 had metastases from lung cancer, and two had sarcomas. A total of 174 patients were followed up for three to 18 months. Only one case with sarcoma that relapsed within half a year of the operation.

Conclusion:

In the treatment of adrenal masses, laparoscopic anatomical adrenalectomy via the renal cortex surface has many advantages including the large operation space, clear view of anatomical markers, little bleeding, small trauma, few postoperative complications, simple operational procedures and short learning curves. This technique needs clinical promotion.

Understanding Retroperitoneal Anatomy for Lateral Approach Spine Surgery

Lateral approach spine surgery provides effective interbody stabilization, and correction and indirect neural decompression with minimal-incision and less invasive surgery compared with conventional open anterior lumbar fusion. It may also avoid the trauma to paraspinal muscles or facet joints found with transforaminal lumbar interbody fusion and posterior lumbar interbody fusion. However, because lateral approach surgery is fundamentally retroperitoneal approach surgery, it carries potential risk to intra- and retroperitoneal structures, as seen in a conventional open anterior approach. There is an innovative lateral approach technique that reveals different anatomical views; however, it requires reconsideration of the traditional surgical anatomy in more detail than a traditional open anterior approach. The retroperitoneum is the compartmentalized space bounded anteriorly by the posterior parietal peritoneum and posteriorly by the transversalis fascia. The retroperitoneum is divided into three compartments by fascial planes: anterior and posterior pararenal spaces and the perirenal space. Lateral approach surgery requires mobilization of the peritoneum and its content and accurate exposure to the posterior pararenal space. The posterior pararenal space is confined anteriorly by the posterior renal fascia, anteromedially by the lateroconal fascia, and posteriorly by the transversalis fascia. The posterior renal fascia, the lateroconal fascia or the peritoneum should be detached from the transversalis fascia and the psoas fascia to allow exposure to the posterior pararenal space. The posterior pararenal space, however, does not allow a clear view and identification of these fasciae as this relationship is variable and the medial extent of the posterior pararenal space varies among patients. Correct anatomical recognition of the retroperitoneum is essential to success in lateral approach surgery. Spine surgeons must be aware that the retroperitoneal membrane and fascia is multilayered and more complex than is commonly understood. Preoperative abdominal images would facilitate more efficient surgical considerations of retroperitoneal membrane and fascia in lateral approach surgery.

Bone single-photon emission computed tomography and three-dimensional computed tomography in the diagnosis of low costal variation and pathologies

In general, there are five lumbar vertebras in normal human subjects. But occasionally there are six. In such a situation, a radiologist need to discern between lumbarization of S1 (S1 vertebra becomes segmented and mimics L5) or due to hypoplastic 12(th) ribs, hence the T12 vertebra is wrongly assumed to be L1. These interesting images serve a multimodality approach to right aplasia/left hypoplasia of 12(th) rib, injury of left 11(th) rib and subluxation of left 11(th) Costovertebral joint in a patient with lumbar back pain.

The urogenital-hypogastric sheath: an anatomical observation on the relationship between the inferomedial extension of renal fascia and the hypogastric nerves

PURPOSE

The study aimed to perform an anatomical observation on the inferomedial extension of the renal fascia (RF) to the pelvis and explore its relationship with the hypogastric nerves (HGNs).

METHODS

Gross anatomy was performed on 12 formalin-fixed and 12 fresh cadavers. Sectional anatomy was performed on four formalin-fixed cadavers.

RESULTS

Different from the traditional concept, both the anterior and posterior RF included the outer and inner layer with different inferomedial extensions. The multiple layers of RF extended downward to form a sandwich-like and compound fascia sheath with potential and expandable spaces which was named as "the urogenital-hypogastric sheath." Below the level of the origin of the inferior mesenteric artery, the bilateral urogenital-hypogastric sheath communicated with the counterpart in front of the great vessels in the midline and the superior hypogastric plexus ran into the urogenital-hypogastric sheath which carried the HGNs, ureters, and genital vessels downward to their terminations in the pelvis. In the retrorectal space, the urogenital-hypogastric sheath surrounded the fascia propria of the rectum posterolaterally as a layer of coat containing HGNs.

CONCLUSION

The multiple layers of RF with different extensions are the anatomical basis of the formation of the urogenital-hypogastric sheath. As a special fascial structure in the retroperitoneal space and the pelvis, emphasis on its formation and morphology may be helpful for not only unifying the controversies about the relationship between the pelvic fascia and HGNs but also improving the intraoperative preservation of the HGNs by dissecting in the correct surgical plane.

Surgical considerations of the renal fascia and the retroperitoneal space around the kidney

Surgical anatomy around the kidney remains controversial. We therefore examined the constitutions of renal fascia and retroperitoneal space around the kidney through the close observations of intraoperative views. The surface of the removed kidney was covered with a smooth membrane, which is the so-called renal fascia. However, such a smooth membrane could not be observed at the dissection site around the kidney during surgery. Only an intricate connective tissue could be observed. On the other hand, using an operative procedure such as dissection or pulling tissue in some direction, an intricate connective tissue changed to a membranous structure. These results suggest that the retroperitoneal area around the kidney would be filled with connective tissue including some fat, which is arranged in a chaotic manner without any specific alignment tridimentionally. As a result of operative procedures, such connective tissue would be grouped, which would be recognized as renal fascia.