BACKGROUND: Gangliocytic paraganglioma is a rare tumors mainly arises from the second part of the duodenum. The tumor is generally benign, but some cases are associated with lymph node or distant metastasis. It must be differentiated from other tumors. The main treatment is good local surgical resection. Most patients have good prognosis after an appropriate resection.
METHODS: A 47-year-old male patient presented with recurrent attacks of epigastric pain and melena. The general examination revealed pallor with no jaundice. The abdomen was soft with no tenderness. There were no stigmata of chronic liver diseases. The hemoglobin level was 8 gm/dl with normal liver and renal functions. The patients received compatible blood. Endoscopy showed a large pedunculated polyp with ulceration in the second part of the duodenum just distal to ampulla of Vater. During surgery, the anterior wall of duodenum was opened, and a 4 cm pedunculated polyp was excised which was arising from the posterior wall of the duodenum just distal to the ampulla of Vater. The frozen section examination revealed a benign lesion. The final histopathology result was consistent with the diagnosis of gangliocytic paraganglioma. The patient had smooth post-operative recovery and no postoperative complications.
CONCLUSIONS: Gangliocytic paraganglioma is a rare tumor which mostly affects the second part of the duodenum. The tumor is considered benign but the possibility of the malignancy with lymphatic and distant metastases must be excluded before any surgery. The management plan must be addressed carefully and continuous follow up is recommended.

OBJECTIVE: Cases of sudden loss of central vision in eyes with silicone oil in situ and after oil removal have been described. The aim of this review is to present current data on silicone oil toxicity to the neuronal aspects of the retina as well as the Cleveland Clinic Abu Dhabi experience with this retinopathy (maculopathy).
METHODS: A PubMed review using the terms \"silicon oil\" and/or \"toxicity\" and/or \"ganglion cell\" and/or \"nerve fiber\" was conducted to identify case reports, case series, and original articles presenting toxicity from silicon oil. Timing of visual loss, as well as SD-OCT data and RNFL/GCC analysis, was collected. Selected cases were pooled from Cleveland Clinic Abu Dhabi Vitreoretinal database to further reinforce the findings.
RESULTS: Twenty-four papers were identified (case/series/articles). The earliest papers that met our criteria seemed to report vision loss at the time of or after silicone oil removal; however, more recent studies have described such toxicity from 1 to 6 months after tamponade with silicone oil in situ. Since the first description of central visual loss from silicone oil, all researchers describe a thinning of perifoveal ganglion cells measured with SD-OCT, while there is no concordance as far as RNFL changes, with some authors describing a thinning and others a thickening, but neither was ever clearly associated with visual loss. The correlation between SD-OCT hyperreflective goblets in the inner retina and histological description of intraretinal oil droplets migration seems to suggest instances of silicone oil penetration in the retinal layers.
CONCLUSIONS: In a small percentage of cases who underwent retinal tamponade with silicone oil, ganglion cells can suffer a direct damage either from particles of oil that migrate in the retina or from direct contact with it. Indirect damage may be caused by phototoxicity due to the transparent nature of silicon oil or by inflammatory damage from cytokines sandwiched between oil and retina.

Proliferative fasciitis is a pseudo-sarcomatous myofibroblastic proliferation characterized by the presence of unusual giant cells resembling ganglion cells, which usually occurs in the adult population with a mean age of 54 years. It usually affects the upper extremities and is rare in head and neck region with only 11 cases described in the literature so far. Because of rapid growth and histological similarity to various malignant tumors such as rhabdomyosarcoma, recognition of this benign condition is a matter of utmost importance when a pathologist is concerned. In this study, we report a case of a 11-year-old boy presented with a lesion on the right side of chin, along with a literature review involving those cases reported in the head and neck region.

BACKGROUND: Hypoganglionosis is a rare condition that most often presents with abnormal gastrointestinal transit and usually arises in early childhood or adolescence. Two types have been described (Type I and Type II). The adult-onset form (acquired hypoganglionosis) is extremely uncommon and is thought to arise due to cellular remodelling as a result of chronic inflammation. It differs from Hirschprung\'s disease in that there is a reduction in ganglion cells in the colonic neural plexuses as opposed to being completely absent.
METHODS: A 31 year-old male presented to hospital with recurrent abdominal pain and vomiting over thirteen months. Abdominal computed tomography scans demonstrated thickening and stranding affecting the transverse, descending and sigmoid colon. Endoscopic appearances were non-specific but confirmed a mixed picture of mucosal inflammation and necrosis in various stages of healing. Numerous investigations were performed to elucidate an underlying aetiology but neither an infective nor ischaemic cause could be proven. Biopsy features were not typical of inflammatory bowel disease. Due to persistence of his symptoms and failure of medical management, a segmental colectomy was performed. Histological examination of the specimen revealed an unexpected finding of segmental hypoganglionosis. Complete surgical excision of the diseased segment of colon was curative and since his operation the patient has had no recurrence of symptoms requiring hospitalisation.
CONCLUSIONS: Our case serves to raise awareness of acquired hypoganglionosis as a rare condition that can result from chronic colitis.

Ganglioneuromas (GNs) are benign tumors composed of ganglion cells in a Schwannian stroma. They are derived from neural crest cells that give rise to the sympathetic nervous system. Hence, GNs can be found anywhere a sympathetic ganglion is present. Most commonly, GNs are found in the posterior mediastinum and abdominal cavity. Within the abdominal cavity, they are most likely to be found in the retroperitoneal space or adrenal glands. Cutaneous involvement is uncommon and rarely reported in literature. We report an interesting case of a cutaneous ganglioneuroma on the abdomen of an 83-year-old male.

Central neurocytoma is a rare neuronal tumor that typically occurs in young adults. Infrequently, these tumors exhibit advanced neuronal maturation and glial differentiation, giving rise to a histologically diverse tumor, in contrast to a typical central neurocytoma. We present a novel case of intraventricular central neurocytoma with prominent gangliogliomatous differentiation that developed atypical features upon recurrence after 10 years of follow up in a 10-year-old boy. Our case provides insight into the divergent differentiation capability of a neurocytic tumor and illustrates the diverse histological features of this rare entity.

BACKGROUND: Accurate diagnosis in patients presenting with lesions at various locations within the visual pathway is challenging. This study investigated functional and structural changes secondary to such lesions to identify patterns useful to guide early and effective management.
METHODS: Over 10,000 records from patients referred for optic nerve head assessment were reviewed and 31 patients with a final diagnosis of likely neuropathic lesions posterior to the eye were included in the current study. Fundus photographs, optic coherence tomography images and visual field tests were evaluated for changes with respect to retinal nerve fibre layer topography and prediction of structure-function paradigms. Emerging clinical patterns were examined for their consistency with the likely anatomical origin of the underlying insult in the presence of varying diagnoses.
RESULTS: Data from patients with lesions along the visual system allowed identification of retinal nerve fibre layer asymmetry correlated with visual field defects and ganglion cell analysis. Bilateral discordance in retinal nerve fibre loss easily discernible from an altered pattern of the temporal-superior-nasal-inferior-temporal curve was characteristic for post-chiasmal lesions. These sometimes-subtle changes supported diagnosis in cases with multiple aetiologies or with ambiguous visual field analysis and/or ganglion cell loss.
CONCLUSIONS: Intricate knowledge of the retinal architecture and projections allows coherent predictions of functional and structural deficits following various lesions affecting the visual pathway. The integration of adjunct imaging and retinal nerve fibre layer thinning will assist clinicians to guide clinical investigations toward a likely diagnosis in the light of significant individual variations. The case series presented in this study aids in differential diagnosis of retrograde optic neuropathies by using retinal nerve fibre layer asymmetric patterns as an important clinical marker.

Traumatic neuromas are characterized by the presence of pain, burning, or paresthesia, associated with a history of trauma, normally surgery, in the same site. In the oral cavity, the most commonly affected sites are the lip, tongue, and mental nerve area. Pressure on the suspected area usually provokes pain. They microscopically consist of a proliferation of nerve fascicles embedded in a background of collagen. We present a case of a 42-year-old Latin American female patient complaining of a painful solitary nodule erupting on the lingual surface of the mandibular body. Histopathological analysis showed a traumatic neuroma associated with mature ganglion cells, which is an extremely unusual finding. After complete removal of the lesion the symptoms disappeared. To the best of our knowledge, this is the first case of a unique lesion with unusual clinical and histopathological features reported in the English language literature.