Amyand’s hernia is defined as when the appendix is trapped within an inguinal hernia. While the incidence of this type of hernia is rare, the appendix may become incarcerated within Amyand’s hernia and lead to further complications such as strangulation and perforation. Incarceration of the appendix most commonly occurs within inguinal and femoral hernias, but may arise to a lesser extent in incisional and umbilical hernias. Incarcerated appendix has been reported in a variety of ventral abdominal and inguinal locations, yet its indistinct clinical presentation represents a diagnostic challenge. This paper reviews the literature on incarceration of the appendix within inguinal hernias and discusses current approaches to diagnosis and treatment of Amyand’s hernia and complications that may arise from incarceration of the appendix within the hernia.

Occipital neuralgia is a debilitating disorder first described in 1821 as recurrent headaches localized in the occipital region. Other symptoms that have been associated with this condition include paroxysmal burning and aching pain in the distribution of the greater, lesser, or third occipital nerves. Several etiologies have been identified in the cause of occipital neuralgia and include, but are not limited to, trauma, fibrositis, myositis, fracture of the atlas, and compression of the C-2 nerve root, C1-2 arthrosis syndrome, atlantoaxial lateral mass osteoarthritis, hypertrophic cervical pachymeningitis, cervical cord tumor, Chiari malformation, and neurosyphilis. The management of occipital neuralgia can include conservative approaches and/or surgical interventions. Occipital neuralgia is a multifactorial problem where multiple anatomic areas/structures may be involved with this pathology. A review of these etiologies may provide guidance in better understanding occipital neuralgia.

Anomalies in the course and drainage of the Inferior Vena Cava (IVC) may complicate normal functioning, correct diagnosis, and therapeutic interventions within the abdomen. Development of the IVC occurs during the 4th to 8th week of gestation, and due to its developmental complexity, there are many opportunities for malformations to occur. Although most IVC anomalies are clinically silent and are usually discovered incidentally on abdominal imaging, aberrations may be responsible for formation of thrombosis, back pain, and anomalous circulation of blood to the heart. In this review, we will discuss the most common variations and abnormalities of the IVC, which include the posterior cardinal veins, the subcardinal veins, the supracardinal veins, persistent left IVC, IVC duplication, situs inversus, left retroaortic renal vein, left circumaortic renal collar, scimitar syndrome, and IVC agenesis. For each abnormality outlined above, we aim to discuss relevant embryology and potential clinical significance with regards to presentation, diagnosis, and treatment as is important for radiologists, surgeons, and clinicians in current clinical practice.

Hindbrain herniations come in many forms and have been further subdivided as their original descriptions. For cerebellar tonsillar ectopia, they can be divided into two categories, acquired and congenital. Acquired hindbrain herniations are due to increased intracranial pressure caused by certain conditions such as trauma or brain tumor. Although the mechanism for their formation is not clear, congenital hindbrain herniation makes up the majority of these congenital malformations. Furthermore, these malformations are often found to harbor additional anatomical derailments in addition to the hindbrain herniation whether it be the cerebellar tonsils (Chiari I malformation) or the cerebellar vermis (Chiari II malformation). This article reviews these forms of cerebellar ectopia and describes the details of their anomalous anatomy. Moreover, this article compares and contrasts the differing embryological theories found in this literature.

The adrenal veins may present with a multitude of anatomical variants, which surgeons must be aware of when performing adrenalectomies. The adrenal veins originate during the formation of the prerenal inferior vena cava (IVC) and are remnants of the caudal portion of the subcardinal veins, cranial to the subcardinal sinus in the embryo. The many communications between the posterior cardinal, supracardinal, and subcardinal veins of the primordial venous system provide an explanation for the variable anatomy. Most commonly, one central vein drains each adrenal gland. The long left adrenal vein joins the inferior phrenic vein and drains into the left renal vein, while the short right adrenal vein drains immediately into the IVC. Multiple variations exist bilaterally and may pose the risk of surgical complications. Due to the potential for collaterals and accessory adrenal vessels, great caution must be taken during an adrenalectomy. Adrenal venous sampling, the gold standard in diagnosing primary hyperaldosteronism, also requires the clinician to have a thorough knowledge of the adrenal vein anatomy to avoid iatrogenic injury. The adrenal vein acts as an important conduit in portosystemic shunts, thus the nature of the anatomy and hypercoagulable states pose the risk of thrombosis.

The lymphatic system of the pancreas is a complex, intricate network of lymphatic vessels and nodes responsible for the drainage of the head, neck, body, and tail of the pancreas. Its anatomical divisions and embryological development have been well described in the literature with emphasis on its clinical relevance in regards to pancreatic pathologies. A thorough knowledge and understanding of the lymphatic system surrounding the pancreas is critical for physicians in providing diagnostic and treatment strategies for patients with pancreatic cancer and pancreatitis. Pancreatic cancer has an extremely poor prognosis and is a notable cause of morbidity and mortality worldwide. Although a surgeon may try to predict the routes for metastasis for pancreatic cancer, the complexity of this system presents difficulty due to variable drainage patterns. Pancreatitis also presents as another severe disease which has been shown to have an association with the lymphatics. The aim of this article is to review the literature on the lymphatics of the pancreas, pancreatic pathologies, and the available imaging methodologies used to study the pancreatic lymphatics.

Genitofemoral neuralgia is a cause of neuropathic pain that is often debilitating in nature. It is characterized by chronic neuropathic groin pain that is localized along the distribution of the genitofemoral nerve. The symptoms include groin pain, paresthesias, and burning sensation spreading from the lower abdomen to the medial aspect of the thigh. It may present with scrotal pain in male, while females experience symptoms radiating to the labia majora and mons pubis. Genitofemoral neuropathy has been attributed to iatrogenic nerve injury occurring during inguinal and femoral herniorrhaphy, with cases developing after both open and laparoscopic techniques. Diagnosis of genitofemoral neuralgia can be challenging, due to the overlap in sensory distribution the nerve shares with the ilioinguinal and iliohypogastric nerve. Differential nerve blocks are recommended in effort to differentiate the nerves when patients present with lower abdominal and groin pain. Once a diagnosis has been made, there exist several treatment options for genitofemoral neuralgia ranging from medical management, non-invasive injections, and surgery. Literature has also brought light to radiofrequency ablation and cryoablation performed under ultrasound guidance as emerging treatments. The aim of the current article is to review the anatomy, diagnostic techniques, and treatment options for patients with genitofemoral neuralgia.

Aortoiliac occlusive disease is a subset of peripheral arterial disease involving an atheromatous occlusion of the infrarenal aorta, common iliac arteries, or both. The disease, as it is known today, was described by the French surgeon René Leriche as a thrombotic occlusion of the end of the aorta. Leriche successfully linked the anatomic location of the occlusion with a unique triad of symptoms, including claudication, impotence, and decreased peripheral pulses. The anatomical location of the atheromatous lesions also has a direct influence on classification of the disease, as well as choice of treatment modality. Considering its impact on diagnosis and treatment, we aimed to provide a detailed understanding of the anatomical structures involved in aortoiliac occlusive disease. Familiarity with these structures will aid the physician in interpretation of radiologic images and surgical planning.