Right perirenal space. Computed tomography evidence of communication between the bare area of the liver

An anatomical, histopathological, and molecular biological function study of the fascias posterior to the interperitoneal colon and its associated mesocolon: their relevance to colonic surgery

The study aim was to explore the anatomy, histopathology, and molecular biological function of the fascias posterior to the interperitoneal colon and its mesocolon to provide information for improving complete mesocolic excision. To accomplish this aim, we performed intraoperative observations in 60 interperitoneal colon-cancer patients accepted for complete mesocolic excision and conducted local anatomy observations for five embalmed cadavers. An additional two embalmed child cadaver specimens were studied with large slices and paraffin sections. Ten of the 60 patients were examined with a lymph node tracer technique in vivo, while fresh specimens from these patients were assessed by histopathological examination and transwell cell migration assays in vitro. The anatomical and histopathological findings showed that the fascias posterior to the interperitoneal colon and its associated mesocolon were composed of two independent layers: the visceral and parietal fascias. These two fascias were primarily composed of collagen fibers, with the parietal fascia containing a small amount of muscle fiber. The in vivo test showed that the visceral fascia surrounded the colon and its associated mesocolon, including vessels and lymphatics, and that it had no lymphatic flow through it into the rear tissues. Moreover, the in vitro assays showed the visceral fascia was able to block tumor cell migration. Although many surgical scholars have known of the existence of fascia tissue posterior to the intraperitoneal colon, the detailed structure has been ignored and been unclear. As shown by our findings, the visceral and parietal fascias are truly formed structures that have not been previously reported. A thorough understanding of fascial structures and the function of the visceral fascia barrier in blocking tumor cells will facilitate surgeons when performing high-quality complete mesocolic excision procedures.

CT evaluation of spontaneously ruptured renal angiomyolipomas with massive hemorrhage spreading into multi-retroperitoneal fascia and fascial spaces

Background

Renal angiomyolipomas (RAMLs) can spontaneously rupture and induce hemorrhage that is usually confined to the perirenal space (PS) but may spread beyond the PS into other retroperitoneal fascia and fascial spaces, including up to the subdiaphramatic and down to pelvic extra-peritoneal regions.

Purpose

To evaluate the computed tomography (CT) manifestations of renal angiomyolipoma (RAML) associated with spontaneous rupture and massive hemorrhage spreading beyond the PS into other retroperitoneal fascia and fascial spaces, including up to the subdiaphramatic and down to pelvic extra-peritoneal regions.

Material and Methods

The CT scans of seven patients with spontaneously ruptured of RAMLs and massive hemorrhage (surgically and pathologically confirmed) were retrospectively reviewed. We evaluated the CT signs of the RAML itself and the regions with extensive retroperitoneal spreading after RAML rupture.

Results

The CT manifestations of seven cases with RAML spontaneous rupture and massive hemorrhage included the following: (a) RAML signs: size (>4.0 cm, five patients; <4.0 cm, two patients), location (periphery, six patients; central portion, one patient), component (fat tissue included, seven patients), and boundary (poorly revealed, seven patients); and (b) signs of extensive retroperitoneal spreading after RAML rupture: involving the PS and extending beyond the PS (seven patients); spread to the pelvic extraperitoneal space (seven patients); attached to the subdiaphragmatic extraperitoneal region (four patients); and extended to the contralateral retroperitoneal spaces (six patients).

Conclusion

CT scans clearly depict both the primary tumor and complicated signs of a spontaneously ruptured RAML with massive hemorrhage, which can affect other fascial planes and retroperitoneal spaces and can extend upward to the subdiaphragmatic region and downward to the pelvic extraperitoneal region or communicate with the contralateral side.

Recommendation for standardized surgical management of primary adrenocortical carcinoma

BACKGROUND

Operative resection is the only potentially curative treatment for primary adrenocortical carcinoma (ACC), but standards of operative care are not defined with regards to the extent of local resection. We propose recommendations for operative management.

METHODS

Anatomic and clinical literature review focusing on local management of ACC, including lymphadenectomy and resection of adjacent organs or large vessels.

RESULTS

First-order drainage nodes of the adrenal gland include the renal hilum lymph nodes, the celiac lymph nodes, and the para-aortic and paracaval lymph nodes, mainly above the renal pedicle and ipsilateral to the adrenal glands. Lymph node involvement occurs in about 20% of patients with ACC, and is an important prognostic factor, but lymphadenectomy is performed infrequently. The adrenal glands and kidneys are contained in the same anatomic space, but systematic en bloc nephrectomy has no proven benefits for survival. Direct invasion of the kidney or adjacent organs is rare, but major venous invasion with tumor thrombus is relatively common. Both are associated with decreased survival, but complete resection can lead to long-term survival.

CONCLUSION

Standardization of regional lymphadenectomy including first-order drainage nodes is proposed. Systematic nephrectomy is not necessary in the absence of gross local invasion, but locally involved organs or large veins should be resected en bloc, with tumor thrombus embolectomy, if R0 resection is possible. Operative standardization improves tumor staging, potentially decreases local recurrence, and may be associated with better survival. Evidence-based standards of operative care and prospective investigations within international collaborating groups are necessary.

Sectional Anatomy of the Peritoneal Reflections of the Upper Abdomen in the Coronal Plane

PURPOSE

The purpose of this study was to provide practical anatomic data for the imaging diagnosis and surgical treatment of the diseases of the subphrenic spaces.

METHODS

The sectional anatomy of the subphrenic spaces on the coronal plane was investigated on serial coronal sections of the upper abdomen of 30 Chinese adult cadavers.

RESULTS

The space between the anterior margin of gastropancreatic fold and the posterior layer of hepatogastric ligament is the only direct pathway between the superior and inferior recesses of the lesser sac. That pathway can be divided into 3 types on the coronal plane. The right layer of the gastrophrenic ligament is continuous with the posterior layer of the lesser omentum, and its left layer is continuous with the right layer of the phrenosplenic ligament and the posterior layer of the gastrosplenic ligament. The gastropancreatic fold is continued to the left and right layers of the gastrophrenic ligament upwards. The bare area of the stomach is located between the left and right layers of the gastrophrenic ligament; its existing rate is 100%. The bare area of the spleen is located among the phrenosplenic ligament, gastrosplenic ligament, splenorenal ligament, and splenocolic ligament. Its greatest width exists between the two layers of the splenorenal ligament. It can be divided into the splenic hilus and splenorenal parts.

CONCLUSION

The coronal section is dominant to show the anatomic relationships of the gastrophrenic ligaments and the gastropancreatic folds, and the bare area of the stomach.

Helical CT evaluation of the perirenal space and its boundaries: a cadaveric study

PURPOSE

To determine whether the perirenal spaces communicate across the midline and with the pelvic extraperitoneal spaces.

MATERIALS AND METHODS

Helical CT was used to guide the sequential injection of 100-mL intravenous boluses of dilute contrast medium, up to 300 mL, into the perirenal space of eight embalmed cadavers (three male, five female; mean age at death, 82 years; range, 72-93 years), with four left-sided and four right-sided injections. All images were acquired after the final injection (300 mL total) to facilitate coronal and sagittal reconstruction of relevant images. All images were reviewed to assess the flow pathways of contrast medium from the perirenal space to other retroperitoneal spaces.

RESULTS

In three cadavers that received left perirenal space injections and in two cadavers that received right perirenal space injections, communication was seen with the contralateral perirenal space through an area anterior to the aorta and inferior vena cava. In three cadavers that received right perirenal space injections, contrast material flowed from the right perirenal space to outline the bare area of the liver. Communication between the perirenal and pelvic extraperitoneal spaces was seen in all eight cadavers; contrast material extended into the pelvic extraperitoneal and presacral spaces.

CONCLUSION

These findings show that the perirenal spaces communicate with each other across the midline and with the pelvic extraperitoneal spaces. Clinical implications are that perinephric collections can potentially flow into the pelvis or across the midline.

Is the renal space closed?

The aim of this study is to verify the aperture or the closure of the renal space. The study is undertaken on histological sections of fetuses in the horizontal and sagittal planes. On each side, the kidney and the suprarenal gland are disposed in a space that is closed on all sides. The anterior and posterior layers of the renal fascia fuse at the upper pole of the space to become continuous with the inferior fascia of the diaphragm. Likewise, they merge at the lower pole and at the lateral border of the space to become continuous with the fasciae of the parietal muscles. At the medial border of the space, the two layers merge to continue medially with the peri-aortocaval connective tissue; they penetrate the hilum and beneath it enclose the ureter.

Anatomical communications of the perirenal space

There are controversies over the anatomical communications between the perirenal space and the adjacent extraperitoneal spaces. Clinical studies, mainly based on CT, show fluid collections extending into the adjacent space; into the bare area of the liver on the right, into the superior extraperitoneal space on the left, towards the midline from each perirenal space, and into the lower retroperitoneal space of the abdomen and pelvis. There are certain constant anatomical barriers limiting free extension of fluid or pathology. The pattern of fluid collection in the perirenal space and extension into the adjacent extraperitoneal space is relatively consistent although it varies with the amount and nature of the pathological fluid collection. This pictorial review illustrates anatomical barriers and CT findings of perirenal fluid collections and their extension into adjacent extraperitoneal spaces.

Continuation of gas from the right perirenal space into the bare area of the liver

PURPOSE

It is difficult to explain some CT findings pertaining the anatomic relationship between the bare area of the liver and the right retroperitoneal space on the basis of the traditional three compartment concept of retroperitoneal anatomy. The purpose of this article is to ascertain and illustrate possible communication between the bare area of the liver and the right perirenal space in patients with gas-forming retroperitoneal infection.

METHOD

We reviewed CT findings in 24 cases with retroperitoneal gas-forming condition with particular emphasis on the extent of the infection and resultant distribution of gas.

RESULTS

CT images showed gas within the right perirenal space extended upward directly into the bare area of the liver in six cases.

CONCLUSION

The right perirenal space is considered open toward the bare area of the liver. Therefore, gas within the perirenal space may communicate directly with the bare area of the liver.

Bare area abscess: imaging findings and potential communication with the mediastinum

The bare area of the liver is not usually visualized by standard cross-sectional imaging techniques except in patients with ascites or subphrenic collections where this area is spared of fluid. We present a case of an abscess in the bare area of the liver with imaging findings and demonstration of a communication with the mediastinum, not previously described.

Silent rectal perforation after endoscopic polypectomy: CT features

A case of silent extraperitoneal rectal perforation secondary to colonoscopic polypectomy is presented. Computed tomography (CT) demonstrated pathways of gas diffusion from the perirectal site to different compartments of the retroperitoneum, to the mediastinum and peritoneum.