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PubMed1992

Treatment of superficial cutaneous pigmented lesions by melanin-specific selective photothermolysis using the Q-switched ruby laser.

The Q-switched ruby laser at 694 nm, a wavelength well absorbed by melanin relative to other optically absorbing structures in skin, causes highly selective destruction of pigment-laden cells. In addition, the 20-nsec pulse duration produced by this laser approximates the thermal relaxation time for melanosomes, thereby confining the energy to the target. This new laser system produces clinically significant fading of superficial cutaneous pigmented lesions in patients, without complications such as hypertrophic scarring or changes in the normal skin pigmentation, often seen with conventional laser systems or other therapeutic methods. In ongoing clinical trials at our facility, excellent results have been obtained for lentigines, café-au-lait macules, nevus spilus, Becker's nevi, and ephelides (freckles), without skin scarring or textural or permanent pigment changes. The purpose of this report is to (1) describe the theoretical considerations that can be understood and used by a nonlaser-oriented practitioner involved in achieving selective removal of superficial cutaneous pigmented lesions, and (2) describe the practical application of the device to the clinical management of patients.

Female↗
PubMed1998

Q-switched ruby laser treatment of tattoos and benign pigmented skin lesions: a critical review.

The Q-switched ruby laser (694 nm, 25-40 nsec) is an effective and safe therapeutic device for the treatment of tattoos and well-defined, benign, pigmented epidermal and dermal lesions. Because of its selective mode of action, dermal pigments of natural and artificial origin are destroyed photothermically and removed without scar. This method is exceptionally suited for the elimination of lay and professional tattoos, traumatic tattoos, and permanent makeup. Other frequent indications include benign pigmented lesions such as lentigines, freckles, café-au-lait spots, seborrheic keratosis, and Becker nevi. As a dermal pigmented lesion, the nevus of Ota is perfectly treatable. However, chloasma can no longer be considered an indication for ruby laser treatment due to unsatisfactory results. Melanocytic nevi and congenital nevi should be treated only in clinical studies. The effectiveness of the long-term epilation of dark hair with this laser device has to be verified in future investigations. Particularly attractive is the nonproblematic and straightforward removal of pigmented lesions in precarious anatomic regions like the lips, eyelids, and genitals (e.g., benign melanosis of the lips or of the penis, seborrheic keratosis of the lid angle).

Dermatologic Surgical Procedures↗
PubMed1991

Macroscopic pigmentation in a dematiaceous fungal keratitis.

The diagnosis of fungal keratitis can be difficult and is often delayed. The distinction between moniliaceous and dematiaceous (pigmented) keratomycoses is not commonly possible on clinical examination. We report a case of a Curvularia lunata fungal keratitis in a 40-year-old patient who presented with diffuse brown pigmentation throughout the ulcer bed. Histologic staining and growth on Sabourad's dextrose agar demonstrated the brown pigmentation characteristic of this pigmented fungus. We call attention to this clinical pigmentation as a helpful clue in the detection of dematiaceous fungal keratitis.

Adult↗
PubMed1985

Relation of graded ocular anterior chamber pigmentation to phenothiazine intake in schizophrenics--quantification procedures.

The fact that larger doses of phenothiazine medications cause more anterior chamber (lens and cornea) pigmentation in schizophrenics has been apparent since the introduction of these neuroleptic drugs nearly 30 years ago. The present study relates the extent of pigmentation to the dose and duration of phenothiazine administration in long-term schizophrenics. An investigation and analysis of the medication records of 272 pigmented schizophrenics show a statistically significant correlation between most of the pigmentation grades and the associated dose of medication. The results indicate that regular biomicroscopy examinations for pigmentation can help confirm medication history and classify schizophrenics.

Anterior Chamber↗
PubMed1997

Density of the human crystalline lens is related to the macular pigment carotenoids, lutein and zeaxanthin.

PURPOSE: Although oxidative stress may play an important role in the development of age-related cataract, the degree of protection reported for antioxidant vitamins and carotenoids has been inconsistent across studies. These varied results may be due in part to the lack of good biomarkers for measuring the long-term nutritional status of the eye. The present experiments investigated the relationship between retinal carotenoids (i.e., macular pigment), used as a long-term measure of tissue carotenoids, and lens optical density, used as an indicator of lens health. METHODS: Macular pigment (460 nm) and lens (440, 500, and 550 nm) optical density were measured psychophysically in the same individuals. Groups of younger subjects--7 females (ages 24 to 36 years), and 5 males (ages 24 to 31 years)--were compared with older subjects--23 older females (ages 55 to 78 years), and 16 older males (ages 48 to 82 years). RESULTS: Lens density (440 nm) increased as a function of age (r = 0.65, p < 0.001), as expected. For the oldest group, a significant inverse relationship (y = 1.53-0.83x, r = -0.47, p < 0.001) was found between macular pigment density (440 nm) and lens density (440 nm). No relationship was found for the youngest group (p < 0.42). CONCLUSIONS: The main finding of this study was an age-dependent, inverse relationship between macular pigment density and lens density. Macular pigment is composed of lutein and zeaxanthin, the only two carotenoids that have been identified in the human lens. Thus, an inverse relationship between these two variables suggests that lutein and zeaxanthin, or other dietary factors with which they are correlated, may retard age-related increases in lens density.

Adult↗
PubMed2001

Amelanotic choroidal nevus and melanoma: cytology, tumor size, and pigmentation as prognostic indicators.

BACKGROUND: Choroidal nevi are fairly common lesions of the posterior pole that can sometimes transform into melanoma, and it is thought that most choroidal melanomas arise from preexisting nevi. Occasionally, these lesions present as nonpigmented or amelanotic variations of their pigmented counterparts. Recent studies suggest a relationship between tumor pigmentation and risk of growth and metastasis, with a better prognosis for lightly pigmented or amelanotic lesions. CASE REPORTS: A case of an amelanotic choroidal nevus and melanoma are presented. In Case 1, a 26-year-old white female was found to have a large amelanotic nevus in the right eye. After 7 years of periodic observation, the lesion has not changed. In Case 2, a 51-year-old white male was diagnosed with a large amelanotic melanoma in the left eye. Due to extensive involvement of the optic nerve, the patient underwent enucleation. Histological evaluation confirmed the lesion as a mixed-cell type malignant amelanotic melanoma. CONCLUSION: Management of choroidal nevi generally consists of periodic observation, and the most widely accepted management of choroidal melanoma is observation, radiotherapy, and transpupillary thermotherapy or enucleation. The therapeutic modality of choice for melanoma will vary depending on the size, growth, and location of the lesion. In addition, recent studies suggest an association between heavy tumor pigmentation, tumor size, cell type, and risk of metastasis. Although many variables will influence the final treatment option, pigmentation of the lesion should also be considered.

Adult↗
PubMed1997

Ring retinal pigment epithelial window defect of the macula in central serous chorioretinopathy.

PURPOSE: Central serous chorioretinopathy is usually a benign disorder, in which resolution of serous subretinal fluid and return to a visual acuity of 20/40 or better is the normal outcome. In unusual cases of central serous chorioretinopathy, chronic subretinal fluid can lead to permanent retinal pigment epithelial depigmentation. In this report, we describe a ring-like (bull's eye) pattern of retinal pigment epithelial atrophy associated with central serous chorioretinopathy. METHODS: We examined eight patients (nine eyes) with central serous chorioretinopathy in whom retinal pigment epithelial window defects encircling the fovea developed. RESULTS: The average duration of symptoms before recognition of a circular window defect was 6 years. Visual acuity at the time of documentation of the ring-like window defect was 20/40 or worse in seven of nine (77%) eyes. Although laser photocoagulation treatment was performed in six of the nine eyes, vision improved two or more lines in only one eye (17%). CONCLUSION: Chronic central serous chorioretinopathy can cause a ring-like (bull's eye) pattern of retinal pigment epithelial window defects encircling the fovea. This pattern of retinal pigment epithelial window defect when seen in patients with central serous chorioretinopathy may indicate that a patient has a more severe form of central serous chorioretinopathy.

Adult↗
PubMed2000

Adult-onset foveomacular pigment epithelial dystrophy: clinicopathologic correlation of three cases.

PURPOSE: The authors describe the clinicopathologic features of three patients with adult onset foveomacular pigment epithelial dystrophy (AOFPED). METHODS: The eyes of three patients were studied ophthalmoscopically and by fluorescein angiography, and obtained postmortem and studied by light and electron microscopy. RESULTS: Histopathologic study of the three patient's eyes disclosed central loss of the retinal pigment epithelium and photoreceptor cell layer with a moderate number of pigment-containing macrophages present in the subretinal space and outer retina. To either side, the retinal pigment epithelium was distended with much lipofuscin. Basal laminar and basal linear deposits were present throughout the central area. No discontinuities of Bruch membrane were present. CONCLUSION: The findings in the eyes of three patients with AOFPED included marked aging changes that are similar to those seen in age-related macular degeneration. Pigmented cells with lipofuscin in the subretinal space account for the vitelliform appearance.

Age of Onset↗
PubMed2003

Transpupillary thermotherapy threshold parameters: funduscopic, angiographic, and histologic findings in pigmented and nonpigmented rabbits.

PURPOSE: To evaluate the effect of pigmentation on threshold fluence levels, needed to produce visible and angiographic lesions, of transpupillary thermotherapy (TTT) in rabbits. METHODS: Six pigmented and nine nonpigmented rabbits underwent TTT with an 810-nm diode laser coupled to a slit-lamp biomicroscope using a spot size of 2 or 3 mm. The power ranged from 80 to 200 mW with 1 to 3 minutes of laser exposure for pigmented rabbits and 750 to 1800 mW with 1 minute of exposure for albino rabbits. These parameters were also evaluated after compression of the globe using the contact lens to induce blanching of the optic nerve head. After the experiment, the eyes were enucleated under deep anesthesia, and the animals were killed immediately. RESULTS: In pigmented rabbits, the threshold fluence with the 2-mm spot size was 229 J/cm2 without compression and 153 J/cm2 with compression. With the 3-mm spot size, the threshold decreased from 200 to 150 mW as the duration of exposure lengthened (2 or 3 minutes), increasing the fluence from 170 to 382 J/cm2. In nonpigmented rabbits, the threshold fluence with the 2-mm spot size was 2,865 J/cm2 without compression and 2,674 J/cm2 with compression. With the 3-mm spot size, the threshold fluence of 1,528 J/cm2 was not affected by compression. Histopathologic studies showed transretinal damage at the lowest levels necessary to achieve angiographic evidence of a treatment lesion or a barely visible funduscopic lesion at the time of treatment. CONCLUSIONS: Nonpigmented rabbits required more than a 12-fold increase in total TTT fluence compared with pigmented rabbits with the 2-mm spot size and a ninefold increase with the 3-mm spot size. Inner and outer retinal damage was seen histopathologically at these levels.

Animals↗
PubMed1996

Spinal pigmented villonodular synovitis: a case report.

STUDY DESIGN: This case report illustrates a young male patient with thoracal spinal pigmented villonodular synovitis who presented with difficulty in walking. OBJECTIVES: The treatment of this lesion with posterior approach for preventing neurological deterioration and follow-up with magnetic resonance imaging studies. SUMMARY OF BACKGROUND DATA: Spinal involvement of pigmented villonodular synovitis rare. It is treated by radical surgical excision. But in some cases, as in our case, surgical total excision of the lesion with a one-stage operation is not possible. For this reason, in such cases, follow-up studies with magnetic resonance images are sufficient. This report represents the 14th case of spinal involvement of pigmented villonodular synovitis. METHODS: The patient presented with difficulty walking and received surgery including posterior decompression and subtotal tumor excision. All neurologic signs and symptoms disappeared in a short period. Postoperatively, follow-up studies with magnetic resonance imaging were performed and regrowth of residual lesion was not detected. RESULTS: The patient was discharged home without neurologic deficit. Follow-up studies with magnetic resonance images showed no regrowth of residual lesion. CONCLUSIONS: The principle of surgical management of spinal lesions causing neurologic deficit is early surgical decompression. Although pigmented villonodular synovitis requires total excision, in the presented case total excision of lesion was impossible, because vertebral body involvement needs an anterior or posterolateral approach. During the 16-month follow up, regrowth of the lesion has not occurred. These observations indicate that surgical decompression and follow-up of a patient with magnetic resonance imaging constitute a satisfactory treatment of pigmented villonodular synovitis.

Adult↗
PubMed2002

Quantitative relationships between pigment-related mRNA and biochemical melanoma markers in melanoma cell lines.

The use of reverse transcription polymerase chain reaction (RT-PCR) analysis of melanoma-specific transcripts for the identification of circulating melanoma cells has shown very variable results in different studies on melanoma patients. We have therefore developed quantitative methods to study both analytical and biological variations as possible causes of this phenomenon. Pigment-related and S-100 beta transcripts were quantified in 12 different melanoma cell lines and related to the amounts of 5-S-cysteinyldopa, pigment and S-100B protein. A real-time PCR method was used and the results were expressed as absolute number of transcripts per cell. Tyrosinase, tyrosinase-related protein (TRP)-1, TRP-2 and MART-1/Melan-A mRNA varied from undetectable (< 10(-4) transcripts/cell) to 10(3) transcripts/cell, i.e. by a factor > 10(7) in the different cell lines. S-100 beta mRNA varied from 2.8 to 165 transcripts/cell, i.e. by a factor of 60. Tyrosinase, TRP-1 and TRP-2 mRNA correlated significantly with the amount of 5-S-cysteinyldopa, an intermediate pigment metabolite (P < 0.001, P < 0.001 and P < 0.01, respectively). The amount of S-100 beta mRNA correlated significantly with the amount of S-100B protein (P < 0.001). No cross-correlations were seen between the pigment-related and S-100-related analytes. We conclude that one reason behind the negative results of RT-PCR measurement of pigment-related mRNA may be that these transcripts are not always expressed in the particular cells present in the patient's blood. Furthermore, variation in the expression of the order of 10(7) must have great impact on the diagnostic sensitivity. Measurement of S-100 beta mRNA would be more sensitive, but the use of this transcript is hampered by its presence in the blood cells.

Antigens, Neoplasm↗
PubMed1995

Pathophysiology of pigment dispersion syndrome and pigmentary glaucoma.

Pigmentary glaucoma results from zonular-pigment dispersion, primarily in young, myopic, white individuals. The concavity of the midperipheral iris allows iridozonular contact. Released pigment is carried to the trabecular meshwork where it resides: (1) benignly, not affecting the intraocular pressure, as in pigment dispersion syndrome; or (2) malignantly, elevating the intraocular pressure, as in pigmentary glaucoma. Small amounts of pigment are quickly phagocytized. If the particulate load is heavy, the cells migrate further along the outflow pathway. The flattening of the iris in pigmentary glaucoma patients receiving iridotomies, along with the backward flow of pigment observed during treatment, demonstrates a greater pressure in the anterior than the posterior chamber. This reverse pupillary block may be due to temporary ocular deformations caused by blinking, as small aqueous aliquots are forced into the anterior chamber. Flattening of the concave iris is the key to current and future management of these patients.

Ciliary Body↗
PubMed2007

Correlation of capsular pseudoexfoliation material and iridocorneal angle pigment with the severity of pseudoexfoliation glaucoma.

PURPOSE: To evaluate the correlation between the amount of pseudoexfoliation (PXF) material on the anterior lens capsule, pigment in the iridocorneal angle, presenting intraocular pressure (IOP) and severity of glaucoma in patients with PXF glaucoma/syndrome. PATIENTS AND METHODS: Anterior lens capsule PXF material and iridocorneal pigment of 98 untreated patients with PXF syndrome/glaucoma were graded from photographs and correlated with untreated IOP and indices of glaucoma severity (cup to disc ratio, and visual field mean deviation, and pattern standard deviation). RESULTS: There was a positive statistically significant correlation between the iridocorneal angle pigmentation and IOP (P=0.047, R2=0.2), but not the indices of glaucoma severity (P>0.13). There was no significant correlation between the anterior lens capsule PXF material and IOP or the indices of glaucoma severity (P>0.42). The grade of angle pigmentation, but not lens PXF, in eyes with IOP >21 mm Hg was significantly higher than in eyes with IOP < or =21 mm Hg (P=0.04). CONCLUSIONS: In patients with PXF syndrome/glaucoma, gonioscopically identified iridocorneal angle pigmentation correlates more strongly with presenting IOP than the amount of PXF material on the anterior lens capsule.

Aged↗
PubMed1995

Topically applied diacylglycerols increase pigmentation in guinea pig skin.

Exposure of human and murine melanocytes in vitro to the diacylglycerol (DAG) 1-oleoyl-2-acetyl-sn-glycerol (OAG) markedly increases melanin production within 24 h. To determine whether OAG can increase melanin production in vivo, increasing concentrations of OAG (10-60 mg/ml) in propylene glycol were applied daily for 5 d to shaved guinea pigs. Dose-dependent increased pigmentation was visible first on days 17-22 and persisted for 10-14 weeks. Peak epidermal melanin content in OAG-treated sites was more than twice that of untreated or vehicle-treated sites, as assessed by computerized image analysis of Fontana-Masson stained biopsy cross sections. In another experiment to assess the mechanism of DAG-mediated pigmentation, guinea pigs received twice daily separate applications of OAG, dipalmitoylglycerol (diC16), dioctanoylglycerol (diC8), each 50 mg/ml, 20 microliters/application, and propylene glycol vehicle alone for 5 d. Increased pigmentation was visible after 10 d in the OAG and diC8 sites but not in diC16 or vehicle sites. These results correlate with the reported ability of these compounds to activate protein kinase C in vitro. In a final experiment, guinea pigs received OAG 25 mg/ml three times daily to one test site, and once daily ultraviolet B (70 mJ/cm2, equivalent to 0.6 minimal erythemal dose) radiation to another for 10 d. The OAG and ultraviolet B test sites developed comparable pigmentation by both clinical and histologic criteria. Our data demonstrate that topically applied DAGs can produce a long-lasting increase in epidermal pigmentation, presumably through protein kinase C activation, which clinically and histologically closely resembles ultraviolet-induced tanning.

Administration, Topical↗
PubMed1981

The proliferative and toxic effects of ultraviolet light and inflammation on epidermal pigment cells.

The ear of the mouse is useful for studying the effects of ultraviolet light on epidermal pigment cells. The quantity of light penetrating into the skin causing an inflammatory response can be assessed easily by measuring with an engineering calipers the swelling of the ear. The inflammatory response of the ear exhibits a linear relationship to the dose of light delivered. We observed that doses of shortwave ultraviolet light which are noninflammatory when repeated at daily intervals induce moderate to severe inflammation. Small doses of psoralen and prolonged exposure to UVA (PUVA) were more inflammatory than larger amounts of psoralen and short exposure to light. Doses of shortwave ultraviolet light and PUVA which produce only a minimal inflammation of the skin stimulate the proliferation of epidermal melanocytes. In contrast, PUVA in doses sufficiently large to cause a marked inflammatory reaction in the skin seems injurious to pigment cells and kills them or causes only a minimal proliferative response. The inflammatory reaction itself does not seem to stimulate or inhibit the proliferation of melanocytes. Prostaglandins A, E, and F2 alpha have no effect on the proliferation of epidermal pigment cells. In contrast, dimethyl sulfoxide (DMSO) and allergic contact dermatitis increase the numerical density of pigment cells. Steroids may block the function of the enzyme tyrosinase. Our experiments indicate that pigment cells, like many other varieties of cells, are susceptible to injury and can be killed at least by large doses of PUVA.

Animals↗
PubMed2000

Genetic and developmental analysis of abdominal pigmentation differences across species in the Drosophila dunni subgroup.

Abdominal pigmentation pattern varies dramatically among the species of the Drosophila dunni subgroup across the islands of the Caribbean. Previously, we developed a quantitative measure of abdominal pigmentation to assess phenotypic variation within and between species of this group. In this paper, we use this quantitative measure in an interspecific genetic analysis to decipher the underlying genetic basis of pigmentation differences between one of the lightest and the darkest species in the group. Our analysis shows that pigmentation expression in different areas of the abdomen is under separate genetic control. For these different abdominal regions, we detected a wide range of genetic effects, including X-linked, autosomal additive, near single-gene dominant, and sex-specific effects. Combining these genetic results with our earlier phenotypic and phylogenetic analyses, we present a simple conceptual model to explain how change in the control of expression of pigmentation has evolved throughout the D. dunni subgroup.

Abdomen↗
PubMed2005

Upregulation of the IFN-gamma-stimulated genes in the development of delayed pigmented spots on the dorsal skin of F1 mice of HR-1 x HR/De.

DNA microarray hybridization was used to measure the changes of mRNA levels over time during the development of delayed pigmented spots on the dorsal skin of F1 mice of HR-1 x HR/De. Upregulation of a number of interferon (IFN)-gamma-stimulated genes was detected in delayed pigmented lesions, suggesting that IFN-gamma may play a pivotal role in the development of delayed pigmented spots in this model. Upregulation of these genes was further supported by the increased protein expression level of IFN-gamma in the lesions. Epidermal infiltration of CD8(+) T lymphocytes and mast cell accumulation in the dermis were observed in delayed pigmented spots. Genes encoding chemokines such as monocyte chemoattractant protein-2 (MCP-2), IFN-inducible protein 10 (IP-10), and monokine induced by IFN-gamma (MIG) were among those upregulated by IFN-gamma. We hypothesize that chemokines produced in the epidermis induce migration of inflammatory cells, such as T lymphocytes, mast cells, and macrophages, to the vicinity of melanocytes. Keratinocytes, T lymphocytes, mast cells, and macrophages would become involved in an interactive network, providing a suitable local environment for melanocyte activation. In this environment, melanocytes are exposed to an extensive array of secreted mediators. Reciprocal activation among these cells to maintain this interactive network results in constitutive melanocyte activation and chronic melanin synthesis in delayed pigmented lesions.

Animals↗
PubMed1978

Cyclophosphamide induced nail pigmentation.

Cyclophosphamide therapy may occasionally cuase black pigmentation of the nails. We report five cases with this side effect and review the data on eleven cases in the literature. These changes start in the proximal nail beds and progress distally; on withdrawal of cyclophosphamide, clearing of the nail pigmentation proceeds in a similar fashion. The development of the nail pigmentation does not bear any relation to the primary condition for which cyclophosphamide was prescribed. The dose of the drug before the onset of pigmentation ranged from 1.2 to 12.3 g; the duration of treatment ranged from 10 days to 26 weeks. The mechanism of the nail pigmentation is unknown.

Adolescent↗