ABSTRACT
Choroidal melanoma is the most common primary intraocular malignancy, yet metastatic disease remains the most common malignancy of the eye. Differentiating these entities is essential as treatment, systemic associations, and prognosis vary dramatically between the two. Established diagnostic criteria are accurate for the diagnosis of uveal melanoma. Yet, metastatic disease may be misdiagnosed as a uveal melanoma in rare cases. We report a case of metastatic clear-cell renal cell carcinoma masquerading as uveal melanoma. A 73-year-old Caucasian man with a history of renal cell carcinoma presented with a 15 × 12 × 7 mm homogenous, pigmented, and acoustically hollow mass without hemorrhage or exudation. The patient was initially treated with plaque radiotherapy with good tumor regression. However, the patient developed pain and vision loss due to total exudative retinal detachment. Subsequent enucleation allowed histopathologic confirmation of clear-cell renal cell carcinoma. Nine years following enucleation, the patient remains in complete remission without evidence of other systemic metastases. Renal cell carcinoma should be considered when evaluating patients with probable uveal melanoma. Delayed-onset ocular metastasis from renal cell carcinoma exhibits an atypical clinical course with the possibility of durable remission following enucleation.
ABSTRACT
OBJECTIVES: Oral clonidine is used to treat hypertension but often produces sedation and severe dry mouth; intrathecal clonidine is used to treat chronic pain but may produce hypotension. This clinical feasibility study was conducted to determine if intrathecal clonidine decreases blood pressure in patients with poorly controlled hypertension. MATERIALS AND METHODS: This prospective, single-arm, open-label study was conducted in ten subjects who were taking at least three antihypertensive medications including a diuretic and had an in-office systolic blood pressure between 140 and 190 mm Hg. On the day of treatment, blood pressure was measured before and after a single lumbar intrathecal dose (150 mcg) of clonidine using an automatic oscillometric device every 10-15 min for four hours. Student's paired t-test was used for statistical comparisons. RESULTS: Maximal reductions in systolic and diastolic blood pressures averaging 63 ± 20/29 ± 13 mm Hg were observed approximately two hours after clonidine administration. Decreases in systolic pressure were strongly correlated with baseline systolic pressure. Clonidine produced a significant decrease in heart rate of 11 ± 7 beats/min. No subject required intravenous fluids or vasopressor rescue therapy, or reported spinal headache. CONCLUSIONS: This is the first clinical study in subjects with hypertension that demonstrates significant and profound acute reductions in blood pressure after a single dose of intrathecal clonidine. Future placebo-controlled, dose-escalating studies are warranted to assess the long-term effects of intrathecal clonidine infusion via an implantable drug pump in patients with treatment-resistant hypertension at risk of stroke or myocardial infarction.
