Megaduodenum is a congenital or acquired dilation and elongation of the duodenum with hypertrophy of all layers that presents as a feeling of gastric fullness, abdominal pain, belching, heartburn, and nausea with vomiting sometimes of food eaten 24 hours prior.Megaduodenum does not let the muscles of the duodenum function properly, the movement of waste material in the intestines gets impaired, which in turn affects digestion and nutrition.This condition is a rare entity in adults, because it may be either primary idiopathic or secondary. The secondary causes include Chagas disease, systematic sclerosis, duodenal stenosis, and visceral myopathy. Signs and Symptoms
The signs of duodenum can vary amongst patients. A high rate of chromosomal damage found in blood lymphocytes can indicate the presence of megaduodenum.Symptoms include:

Dilated Duodenum
Abdominal distention
Nausea
Vomiting and diarrhea
Severe digestive pseudo-obstruction
Recurrent urinary retention
Vacuolar degeneration and fibrosis of the longitudinal layer of gastrointestinal muscle.It is possible that this disease can be misdiagnosed and mimic other intestinal disorders, or later increase the chances of becoming a tumor. Causes
Although environmental factors can play a role in the development of Megaduodenum, genetic factors are responsible for creating tumors. Therefore, many complications of chromosomal damage in the blood lymphocytes can be possible causes. However, the main causes are:
Annular pancreas
Adhesions
Systemic sclerosis
Superior mesenteric artery syndrome
Aneurysm. Duodenal atresiaMegaduodenum due to its duodenal ganglionitis is an unusual condition, Megaduodenums similarity to megacolon and megaesophagus diseases can better explain the most plausible causes of it. In addition, some theories state that megaduodenum can be associated with the following causes: post-vagotomy, vitamin deficiency, and collagen diseases.
By reformatting these transverse images or taking coronal images, the examination of orbital floor and roof is permitted. Helical scanning is preferred as it has a lower imaging time and radiation dose comparing to conventional scanning, especially when reforming transverse helical scans into coronal images. The staging of orbital emphysema can then be determined with visual acuity examination and ophthalmoscopy. A disadvantage of using a CT scan is that when detecting air after orbital trauma, the presence of a wooden foreign object can give a false positive result of orbital emphysema. The wooden object can mimic the presence of orbital emphysema. Therefore, patients’ medical history is crucial in making the correct diagnosis. Other tests
Conventional radiography is commonly employed for imaging orbital injuries and identifying orbital fractures. It can be used to diagnose orbital emphysema because it shows the presence of air in the orbit best while the patient is standing upright. Skull films of posterior-anterior, lateral projections, and orbital rim views are recommended to show fractures in orbital rims and walls. However, CT scan is better than conventional radiography in the diagnosis of the condition, as it has a lower high false-negative rate and non-diagnostic rate.Orbital emphysema can also be diagnosed by magnetic resonance imaging (MRI). Although MRI has a low sensitivity for detecting orbital fractures, it can be used to evaluate rectus muscle pathology, optic nerve pathology, and brain pathology, as well as vascular injury. Treatment
Orbital emphysema on its own is a mild and self-limiting disease.