Zoning inside the renal fascia: The anatomical relationship between the urinary system and perirenal fat

Retroperitoneum revisited: a review of radiological literature and updated concept of retroperitoneal fascial anatomy with imaging features and correlating anatomy

PURPOSE

Spread of disease in the retroperitoneum is dictated by the complex anatomy of retroperitoneal fasciae and is still incompletely understood. Conflicting reports have led to insufficient and incorrect anatomical concepts in radiological literature.

METHODS

This review will discuss previous concepts prevalent in radiological literature and their shortcomings will be highlighted. New insights from recent anatomical and embryological research, together with imaging examples, will be used to clarify patterns of disease spread in the retroperitoneum that remain unexplained by these concepts.

RESULTS

The fusion fascia and the renal fascia in particular give rise to planes and spaces that act as vectors for spread of disease in the retroperitoneum. Some of these planes and structures, such as the caudal extension of the renal fascia, have previously not been described in radiological literature.

CONCLUSION

New insights, including the various fasciae, potential spaces and planes, are incorporated into an updated combined retroperitoneal fascial concept.

Cadaveric analysis of surgical techniques and working space for retroperitoneal tumors as model for improving resection of neuroblastoma

PURPOSE

Neuroblastoma, the most common extracranial solid tumor in children under 5 years, often surrounds visceral arteries. This study aimed to analyze the working space provided by standardized surgical techniques at key arterial landmarks in adult cadavers.

METHODS

We assessed in eight adult cadavers the mobilization of the left colon, spleen and pancreas, right colon, duodenum and mesenteric root, access to the bursa omentalis. The average working space score (AWSS) was evaluated at the left and right renal artery, left and right side of the coeliac trunk, superior mesenteric and common hepatic artery. The score was defined as: (0) vessel not visible, (1) working space at the vessel ≤ 1x diameter of the aorta, (2) < 3x the diameter of the aorta, (3) ≥ 3x diameter of the aorta.

RESULTS

The maximum AWSS of 3 was achieved at key vascular landmarks through specific mobilization techniques.

CONCLUSION

Additional mobilization of spleen, pancreas and mesenteric root and access to the bursa omentalis increase surgical working space at major visceral arteries. The results of our investigation provide surgeons with a useful guide to prepare for abdominal neuroblastoma resection.

Interfascial planes as surgical landmarks for laparoscopic upper retroperitoneal surgery: a cadaveric and retrospectively clinical study

Background

Radiologists currently accept the concept of "interfascial plane (IFP)" to understand retroperitoneal anatomy, replacing Meyers' classic tricompartmental theory. Despite much research on retroperitoneal anatomy, its anatomical structure, embryonic origin and developmental process still require further exploration to guide the optimization of surgical process. This study aims to explore the anatomical basis of IFP related to laparoscopic upper retroperitoneal surgery (LURS) and to compare the clinical outcomes of trans-interfascial plane procedures for LURS (TIFP-LURS) with conventional LURS (Con-LURS).

Methods

The study consisted of two parts: cadaveric and clinical study. The cadaveric study involved dissecting and observing the retroperitoneal fasciae and IFP in 32 cadavers using gross anatomical and histological methods. This retrospective clinical study compared the perioperative data and complications of 229 patients who underwent TIFP-LURS and 121 patients who underwent Con-LURS for upper retroperitoneal lesions at our center.

Results

The cadaveric study revealed that the retroperitoneal space was composed of multilaminar fasciae that formed potential bloodless spaces among them, that could be used as surgical landmarks and operating planes. The clinical study showed that TIFP-LURS had a significantly less estimated blood loss, lower intraoperative complication rate, lower postoperative complication rate, shorter hospital-stay and lower long-term postoperative complications rate than Con-LURS. Multivariate analysis indicated that the TIFP procedure was an independent protective factor for decreasing the risk of postoperative complications.

Conclusions

The IFP are potential avascular spaces that can be used during laparoscopic surgery, and TIFP-LURS is a novel surgical approach that can improve the safety and efficacy of laparoscopic surgery for upper retroperitoneal lesions.

Local Renal Treatments for Acute Kidney Injury: A Review of Current Progress and Future Translational Opportunities

Acute kidney injury (AKI) constitutes a significant public health concern, with limited therapeutic options to mitigate injury or expedite recovery. A novel therapeutic approach, local renal treatment, encompassing pharmacotherapy and surgical interventions, has exhibited positive outcomes in AKI management. Peri-renal administration, employing various delivery routes, such as the renal artery, intrarenal, and subcapsular sites, has demonstrated superiority over peripheral intravenous infusion. This review evaluates different drug delivery methods, analyzing their benefits and limitations, and proposes potential improvements. Renal decapsulation, particularly with the availability of minimally invasive techniques, emerges as an effective procedure warranting renewed consideration for AKI treatment. The potential synergistic effects of combined drug delivery and renal decapsulation could further advance AKI therapies. Clinical studies have already begun to leverage the benefits of local renal treatments, and with ongoing technological advancements, these modalities are expected to increasingly outperform systemic intravenous therapy.

Abdominal adipose tissue and type 2 diabetic kidney disease: adipose radiology assessment, impact, and mechanisms

Diabetic kidney disease (DKD) is a significant healthcare burden worldwide that substantially increases the risk of kidney failure and cardiovascular events. To reduce the prevalence of DKD, extensive research is being conducted to determine the risk factors and consequently implement early interventions. Patients with type 2 diabetes mellitus (T2DM) are more likely to be obese. Abdominal adiposity is associated with a greater risk of kidney damage than general obesity. Abdominal adipose tissue can be divided into different fat depots according to the location and function, including visceral adipose tissue (VAT), subcutaneous adipose tissue (SAT), perirenal adipose tissue (PAT), and renal sinus adipose tissue (RSAT), which can be accurately measured by radiology techniques, such as computed tomography (CT) and magnetic resonance imaging (MRI). Abdominal fat depots may affect the development of DKD through different mechanisms, and radiologic abdominal adipose characteristics may serve as imaging indicators of DKD risk. This review will first describe the CT/MRI-based assessment of abdominal adipose depots and subsequently describe the current studies on abdominal adipose tissue and DKD development, as well as the underlying mechanisms in patients of T2DM with DKD.

Cardiorenal Fat: A Cardiovascular Risk Factor With Implications in Chronic Kidney Disease

There is a growing interest in the potential role of adipose tissues in cardiac and renal pathophysiology, and determining the mechanisms by which fat compartments around the heart and kidneys influence cardiovascular disease is of clinical importance in both general and high-risk populations. Epicardial fat and perirenal fat have been associated with adverse outcomes in chronic kidney disease (CKD) patients. Epicardial fat is a rich source of free fatty acids and is capable of secreting inflammatory and pro-atherogenic cytokines that promote atherosclerosis through a local paracrine effect. Recent evidence has demonstrated that perirenal fat has a closer correlation with kidney diseases than other visceral fat deposits in obesity or metabolic disturbances. Moreover, perirenal fat has been reported as an independent risk factor for CKD progression and even associated with cardiorenal dysfunction. Accordingly, these forms of organ-specific fat deposits may act as a connecter between vascular and cardiorenal disease. This review explores the possible links between epicardial and perirenal fat and its significant role as a modulator of cardiorenal dysfunction in CKD patients.