Odontogenic keratocysts are usually noted as incidental radiographic findings. Radiographically they can be seen as unilocular or multilocular radiolucencies. They can be mistaken for other cysts such as residual cysts or a dentigerous cyst if they occur over an unerupted tooth. Pathogenesis
Odontogenic keratocysts originate from the odontogenic epithelium (dental lamina) in the alveolus left from tooth development stages. They are mainly thought to arise from rests of Serres. Genetics
Sporadic (non-syndromic) and syndromic OKCs are associated with mutations in the gene PTCH found on chromosome 9q, which is part of the Hedgehog signaling pathway. PTCH is a tumour suppressor gene. Loss of PTCH activity leads to a brake in the cell cycle. A third of OKCs show mutations in PTCH, resulting in the cyst epithelium undergoing highly proliferative activity. This leads to growth of the cyst wall and when removed favours recurrence if following incomplete removal of the epithelium. Nevoid basal-cell carcinoma syndrome
Multiple odontogenic keratocysts are a feature, and major diagnostic criteria, of nevoid basal cell carcinoma syndrome (NBCCS, also known as Gorlin-Goltz Syndrome). Almost all individuals with NBCCS have odontogenic keratocysts which require numerous treatments. Consideration of the syndrome needs to be taken into account if found in children or if multiple OKCs are present; diagnosis of multiple OKCs in a child necessitates referral for genetic evaluation. Histologically, the cysts are indistinguishable to non-syndromic cysts and over 80% will have PTCH mutations. Diagnosis
Diagnosis is usually radiological. However, definitive diagnosis is through biopsy.
Cyclopentolate is a muscarinic antagonist. It is commonly used as an eye drop during pediatric eye examinations to dilate the eye (mydriatic) and prevent the eye from focusing/accommodating (cycloplegic). Cyclopentolate or atropine can also be administered to reverse muscarinic and central nervous system effects of indirect cholinomimetic (anti-AChase) administration. It is on the World Health Organizations List of Essential Medicines.After instillation of cyclopentolate, pupil dilation (mydriasis) typically lasts up to 24 hours, while paralysis of the ciliary muscle (cycloplegia) typically lasts 6-24 hours. During this time, patients may be more light sensitive than normal and may notice close objects blurred (and possibly distant objects blurred, depending on the patients visual system). Cyclopentolate is often chosen as a milder, shorter-lasting, cycloplegic alternative to atropine, another cycloplegic agent which lasts much longer. Tropicamide is an even shorter-lasting cycloplegic than cyclopentolate, but is less reliable for finding latent hyperopia. Cyclopentolate drops act rapidly to dilate the pupil.The side and adverse effects of cyclopentolate are similar to the side and adverse effects of other anticholinergic medications. Because of that, extra caution should be taken when prescribing cyclopentolate to patients who are already taking other anticholinergic drugs. A possible ocular (eye-related) side effect is increase in pressure inside the eye, which is of particular concern when there is a predisposition toward or a presence of glaucoma. Other ocular side effects can include burning sensations, discomfort with bright light (photophobia), blurred vision, irritation, inflammation of the eye mucous membranes (conjunctivitis), inflammation of the cornea of the eye (keratitis), and other issues.