It can also result if the ventral pancreatic bud fails to fully rotate, so it remains on the right or if the dorsal bud rotates in the wrong direction, such that the duodenum is surrounded by pancreatic tissue. Blockage of the duodenum develops if inflammation (pancreatitis) develops in the annular pancreas. Diagnosis
Postnatal diagnostic procedures include abdominal x-ray and ultrasound, CT scan, and upper GI and small bowel series. Abdominal radiography can show the classic sign of the "double bubble": the presence of air in the stomach and duodenum. Unfortunately, this double-bubble sign is not pathognomonic for annular pancreas, as it can also be observed in other conditions, such as duodenal atresia and intestinal malrotation. Upper GI series may be suggestive of annular pancreas, especially if they show a duodenal narrowing of the second portion of the duodenum and the concomitant dilatation of the proximal duodenum. In some cases it is possible to have signs of inverse peristalsis of the duodenal tract which is proximal to the narrowing caused by the annular pancreas, and the dilatation of the duodenal portion distal to the anomaly. An abdominal CT scan or an MRI allows to highlight the narrowing of the descending duodenal tract and the ring of pancreatic tissue surrounding the duodenum: this ring can be complete or, in patients with an incomplete annular pancreas, extended in a postero-lateral or anterolateral direction with respect to the second part of the duodenum.
Occlusions of the branches of the PCA that supply the thalamus can result in central post-stroke pain and lesions to the subthalamic branches can produce “a wide variety of deficits”.Left posterior cerebral artery syndrome presents alexia without agraphia; the lesion is in the splenium of the corpus callosum. Signs and symptoms
Peripheral Territory Lesions

Contralateral homonymous hemianopsia
cortical blindness with bilateral involvement of the occipital lobe branches
visual agnosia
prosopagnosia
dyslexia, Anomic aphasia, color naming and discrimination problems
memory defect
topographic disorientationCentral Territory Lesions

central post-stroke (thalamic) pain: spontaneous pain, dysesthesias and sensory impairments
involuntary movements: chorea, intention tremor, hemiballismus
contralateral hemiplegia
Weber’s syndrome: occulomotor nerve palsy
Bálints syndrome: loss of voluntary eye movements optic ataxia, asimultagnosia (inability to understand visual objects)

Diagnosis
1.CT
2.MRI

Treatment
References


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