The American Association for the Surgery of Trauma Organ Injury Scale 2018 update for computed tomography-based grading of renal trauma: a primer for the emergency radiologist

The application of deep learning in abdominal trauma diagnosis by CT imaging

BACKGROUND

Abdominal computed tomography (CT) scan is a crucial imaging modality for creating cross-sectional images of the abdominal area, particularly in cases of abdominal trauma, which is commonly encountered in traumatic injuries. However, interpreting CT images is a challenge, especially in emergency. Therefore, we developed a novel deep learning algorithm-based detection method for the initial screening of abdominal internal organ injuries.

METHODS

We utilized a dataset provided by the Kaggle competition, comprising 3,147 patients, of which 855 were diagnosed with abdominal trauma, accounting for 27.16% of the total patient population. Following image data pre-processing, we employed a 2D semantic segmentation model to segment the images and constructed a 2.5D classification model to assess the probability of injury for each organ. Subsequently, we evaluated the algorithm's performance using 5k-fold cross-validation.

RESULTS

With particularly noteworthy performance in detecting renal injury on abdominal CT scans, we achieved an acceptable accuracy of 0.932 (with a positive predictive value (PPV) of 0.888, negative predictive value (NPV) of 0.943, sensitivity of 0.887, and specificity of 0.944). Furthermore, the accuracy for liver injury detection was 0.873 (with PPV of 0.789, NPV of 0.895, sensitivity of 0.789, and specificity of 0.895), while for spleen injury, it was 0.771 (with PPV of 0.630, NPV of 0.814, sensitivity of 0.626, and specificity of 0.816).

CONCLUSIONS

The deep learning model demonstrated the capability to identify multiple organ injuries simultaneously on CT scans and holds potential for application in preliminary screening and adjunctive diagnosis of trauma cases beyond abdominal injuries.

Predictive factors for nephrectomy in renal trauma; assessment of a 6-point score

PURPOSE

To evaluate predictive and associated risk factors for nephrectomy in renal trauma and assess a 6-point score for surgical decision-making.

PATIENTS AND METHODS

This multicenter, retrospective, and observational study assessed 247 subjects with blunt or penetrating kidney trauma. Kidney injuries were classified according to the American Association for the Surgery of Trauma (AAST) Injury Scoring Scale. Renal trauma was classified as "low-grade" (Grades I-III), Grade IV, and Grade V. Subjects were compared according to conservative treatment (CTrt.) or nephrectomy. Predictive factors were evaluated with a multiple regression model. A 6-point score was evaluated with a ROC analysis.

RESULTS

Patients requiring nephrectomy had a lower mean arterial pressure MAP compared to CTrt, 64.71 mmHg (SD ± 10.26) and 73.86 (SD ± 12.42), respectively (p =  < 0.001). A response to IV solutions was observed in 90.2% of patients undergoing CTrt. (p =  < 0.001, OR = 0.211, 95%CI = 0.101-0.442). Blood lactate ≥ 4 mmol/L was associated with nephrectomy (p =  < 0.001). A hematoma ≥ 25 mm was observed in 41.5% of patients undergoing nephrectomy compared to 20.1% of CTrt. (p = 0.004, OR = 9.29, 95% CI = 1.37-5.58). A logistic regression analysis (p =  < 0.001) showed that blood lactate ≥ 4 mmol/L (p = 0.043), an inadequate response to IV solutions (p = 0.041) and renal trauma grade IV-V (p =  < 0.001), predicted nephrectomy. A 6-point score with a cut-off value ≥ 3 points showed 83% sensitivity and 87% specificity for nephrectomy with an AUC of 89.9% (p =  < 0.001).

CONCLUSIONS

An inadequate response to IV solutions, a lactate level ≥ 4 mmol/L, and grade IV-V renal trauma predict nephrectomy. A score ≥ 3 points showed a good performance in this population.

CT findings in renovascular injuries following abdominal trauma: a pictorial review

Renal vascular injuries are more devastating than parenchymal injuries alone, thus account for higher injury grade and require prompt recognition. Revised AAST organ injury scale (OIS) for renal trauma has incorporated CT-diagnosed vascular injuries into renal injury grading which includes pseudoaneurysm and arteriovenous fistula, along with addition of some new descriptors of renovascular injury. Dual-phase contrast-enhanced CT (with both arterial and venous phase) can easily pick up renovascular injuries and is the modality of choice for imaging renovascular trauma. Radiologist should be well versed with the imaging findings of renovascular injuries so that accurate injury grading can be done and further management can be planned at the earliest.

Interventional radiology in renal emergencies: a pictorial essay

Renal emergencies necessitate prompt diagnosis and management to stop active bleeding and retain kidney function. Causes of renal emergencies can be classified into traumatic, atraumatic, iatrogenic, and obstructive etiologies. Interventional radiology (IR) has emerged as an acceptable alternative to surgical treatment in the management of renal emergencies due to its minimally invasive nature. With the rise of interventional procedures, there is a need for further discussion of angiographic and fluoroscopic imaging in the setting of renal emergencies.

Non-Operative Management with Angioembolization of Grade IV and V Renal Injuries in a Hybrid Emergency Room System

<p>Renal injuries occur in more than 10% of patients who sustain blunt abdominal injuries. Non-operative management (NOM) is the established treatment strategy for lowgrade (I–III) renal injuries. However, despite some evidence that NOM can be successfully applied to high-grade (IV, V) renal injuries, it remains unclear whether NOM is appropriate in such cases. The authors report two cases of high-grade renal injuries that underwent NOM after embolization in a hybrid emergency room (ER) system with a 24/7 in-house interventional radiology (IR) team. A 29-year-old male visited Wonkwang University Hospital Regional Trauma Center complaining of right abdominal pain after being hit by a rope. Computed tomography (CT) was performed 16 minutes after arrival, and the CT scan indicated a grade V right renal injury. Arterial embolization was initiated within 31 minutes of presentation. A 56-year-old male was transferred to Wonkwang University Hospital Regional Trauma Center with a complaint of right flank pain. He had initially presented to a nearby hospital after falling from a 3-m height. Thanks to the key CT images sent from the previous hospital prior to the patient’s arrival, angiography was performed within 8 minutes of the patient’s arrival and arterial embolization was completed within 25 minutes. Both patients were treated successfully through NOM with angioembolization and preserved kidneys. Hematoma in the first patient and urinoma in the second patient resolved with percutaneous catheter drainage. The authors believe that the hybrid ER system with an in-house IR team could contribute to NOM and kidney preservation even in high-grade renal injuries.</p>

Renal Arteries Revisited: Anatomy, Pathologic Entities, and Implications for Endovascular Management

The renal arteries (RAs) are important vessels that usually arise from the abdominal aorta and supply the kidneys; thus, these arteries play a vital role in physiologic functions such as hemofiltration and blood pressure regulation. An understanding of the basis for embryologic development and the frequently variable anatomy of the RAs is necessary to fully appreciate the range of diseases and the implications for procedural planning. Hemorrhage from an RA is relatively common and is typically traumatic or spontaneous, with the latter form often seen in association with underlying tumors or arteriopathy. Accurate diagnostic evaluation of RA disease due to conditions such as atherosclerosis, fibromuscular dysplasia, vasculitis, aneurysm, arteriovenous shunt, embolic disease, and dissection is dependent on the use of multimodality imaging and is essential for selecting appropriate clinical management, with endovascular therapy having a key role in treatment. Surgical considerations include extra-anatomic renal bypass, which remains an important treatment option even in this era of endovascular therapy, and RA embolization as an adjunct to tumor surgery. A novel area of research interest is the potential role of RA denervation in the management of refractory hypertension. ^©RSNA, 2021.

Review of Multimodality Imaging of Renal Trauma

Blunt trauma accounts for more than 95% of traumatic renal injury and results from shear forces from rapid acceleration or deceleration and/or collision against the spine or ribs. The use of multiphasic contrast-enhanced computed tomography (CT) has proven pivotal in the evaluation and management of traumatic kidney injury, and CT imaging features provide the basis for nonsurgical staging. This article describes the epidemiology and mechanisms of blunt and penetrating traumatic renal injury and reviews the range of findings from various imaging modalities, with a particular emphasis on contrast-enhanced CT.