The limbus vertebra is formed due to anterior herniation of the nucleus pulposus between the ring apophysis and the adjacent vertebral body, resulting in the formation of a triangular, smooth bony fragment that ossifies separately. It is commonly located in the mid-lumbar spine, usually at the antero-superior margin of a single vertebral body. We present the case of a 31-year-old male who presented to the Emergency Department with complaints of sciatica after bending forwards. The plain radiograph of the lumbosacral spine was suspicious for a L5 chip fracture but was diagnosed to have limbus vertebra and discharged. Limbus vertebra is generally identified incidentally, and most patients with anterior limbus vertebra are asymptomatic. Some patients with posterior limbus vertebra can present with symptoms of nerve compression. It can be mistaken for vertebral fracture, infection, degenerative disease of the spine or tumour, resulting in further diagnostic evaluation. Most patients are management conservatively, while those patients with symptoms of nerve compression requiring total laminectomy. Emergency physicians should consider the limbus vertebra as a differential diagnosis in patients presenting with lumbar pain, particular in young patients.

Introduction: Corneal epithelial cells are destroyed naturally and the limbal stem cells replace them by multiplying and differentiating. In case of defects in these cells, it is impossible to replace them, and in many cases, the patients lose their vision. One of the newest methods of treating limbal stem cell deficiency (LSCD) is to cultivate them in the laboratory and transfer them to the patient's eye. For this purpose, in this study, we aimed to culture limbal stem cells in vitro and optimized the culture quality. Material and Method: First, the limbus region of the donated eye samples was separated. Then the separated parts were cultured on the amniotic membrane by the explant method. The presence and proliferation of limbal stem cells were investigated by immunofluorescent method and antibody against Δ, NP63α,and ABCG2 markers on the 10th, 14th, and 21st days. Also, by using the flow cytometry method and antibody against Δ, NP63α,marker, the percentage of limbal cells on the best day of their culture based on immunofluorescent results was determined. Results: Findings showed that limbal stem cells could be cultured properly in vitro. All immunofluorescent assays confirmed limbal stem cell attendance, however, the result of day 14th of culture was more considerable. Therefore, the flow cytometry assay was performed on the 14th day and proved that there were 5. 8% limbal stem cells using explant culture. Conclusion: The results indicated the successful cultivation of limbal cells in laboratory conditions, but for their clinical application, further optimization of cultivation is required.

Purpose: To report the clinical and histopathological features of recurrent atypical fibrous histiocytoma of the comeo-sclerallimbus followed by intra-epithelial squamous neoplasia.Case Report: A 25-year-old female patient presented with a recurrent vascularized gelatinous mass in the left nasal limbus. The preliminary histopathological diagnosis of the previously excised lesion was an amelanotic malignant melanoma at a private general pathology center. The lesion had recurred after one year and the histopathologic diagnosis was a poorly differentiated malignant melanoma at another pathology center. The lesion recurred again and the specimen was sent to a third histopathologic center where the histopathologic diagnosis revealed spindle cell growth with moderate atypia. A pannus-like lesion occurred in the nasal limbus 3 years later which was excised and sent to the Eye Bank Pathology Laboratory. Reviewing the slides related to the first recurrent lesion and the histopathologic examination of the recently excised specimen disclosed a final diagnosis of atypical fibrous histiocytoma and intra-epithelial squamous neoplasia, respectively.Conclusion: Fibrous histiocytoma is a rare limbal tumor that may have atypical features and can be misdiagnosed as an amelanotic melanoma. This is also a rare report on the occurrence of intraepithelial squamous neoplasia following excision of recurrent fibrous histiocytoma.

Metastatic neoplasms to the ocular surface are extremely rare. Here, we describe a case of A 56-year-old man developed simultaneously a limbal and parotid gland masses in his left side. He underwent excisional biopsy of limbal mass, parotidectomy, and systemic evaluation. Histopathologically, multislice sections of both limbal and parotidal masses disclosed an undifferentiated carcinoma of both sites. Further evaluation revealed no other site of involvement and metastasis. The patient underwent systemic chemotherapy and local radiotherapy for parotid gland tumor. Distal metastasis from undifferentiated carcinoma of the parotid gland to ocular surface is very rare and to the best of our knowledge has not been previously reported. This is the first report of the manifestation of metastasis from undifferentiated carcinoma of parotid gland origin to the limbus. The limbal mass may be the initial manifestation of metastasis from this origin and should be considered in the differential diagnosis of a metastatic limbal tumor.