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Wulf HC. Daylight PDT acts by continuous activation of PpIX. Photodiagnosis Photodyn Ther 2019; 27:A1-A2. [PMID: 30986540 DOI: 10.1016/j.pdpdt.2019.04.012] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2019] [Accepted: 04/10/2019] [Indexed: 11/17/2022]
Affiliation(s)
- Hans Christian Wulf
- Department of Dermatology, Bispebjerg Hospital, University of Copenhagen, Denmark.
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2
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Ibbotson S, Wong T, Morton C, Collier N, Haylett A, McKenna K, Mallipeddi R, Moseley H, Rhodes L, Seukeran D, Ward K, Mohd Mustapa M, Exton L. Adverse effects of topical photodynamic therapy: a consensus review and approach to management. Br J Dermatol 2018; 180:715-729. [DOI: 10.1111/bjd.17131] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/24/2018] [Indexed: 12/21/2022]
Affiliation(s)
- S.H. Ibbotson
- Photobiology Unit Department of Dermatology University of Dundee Ninewells Hospital and Medical School Dundee U.K
| | - T.H. Wong
- Stirling Community Hospital StirlingU.K
| | | | - N.J. Collier
- Photobiology Unit Dermatology Centre University of Manchester and Salford Royal NHS Foundation Trust ManchesterU.K
| | - A. Haylett
- Photobiology Unit Dermatology Centre University of Manchester and Salford Royal NHS Foundation Trust ManchesterU.K
| | - K.E. McKenna
- Department of Dermatology Belfast City Hospital BelfastU.K
| | - R. Mallipeddi
- St John's Institute of Dermatology Guy's and St Thomas’ NHS Foundation Trust London U.K
| | - H. Moseley
- Photobiology Unit Department of Dermatology University of Dundee Ninewells Hospital and Medical School Dundee U.K
| | - L.E. Rhodes
- Photobiology Unit Dermatology Centre University of Manchester and Salford Royal NHS Foundation Trust ManchesterU.K
| | | | | | | | - L.S. Exton
- British Association of Dermatologists London U.K
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3
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Abstract
Conventional photodynamic therapy (PDT) is associated with side effects, primarily related to the waiting time between pretreatment with application of photosensitizer and illumination. Pain during illumination is a major issue for the patients and options for effective pain relief are limited. Post-treatment inflammation can often be severe and cause inconvenient down-time for the patients and their employers. To avoid the problems of pain and patients crowding in the clinic we eliminated red light treatment of high PpIX concentration and introduced illumination in daylight which may be performed at home. We also investigated if protoporphyrin IX (PpIX) could be activated continuously during its formation which might reduce pain and inflammation. Continuous activation of PpIX during its formation turned out to minimize pain as single PpIX molecules are activated continuously without accumulation of PpIX in the skin. PpIX molecules are formed in the mitochondria and the photodynamic effect only takes place in the mitochondria when continuously activated. This results primarily in apoptosis with little inflammation. Continuous activation of PpIX can be obtained by performing photodynamic therapy in daylight, as well as with daylight-emitting light sources of appropriate wavelengths. Use of daylight prevents the patients from crowding in the clinic. Daylight-PDT completely fulfils the purpose of minimizing pain and inflammation, as well as limiting the strain on the clinic treating the patients.
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Affiliation(s)
- Hans C Wulf
- Department of Dermatology, Bispebjerg Hospital, University of Copenhagen, Copenhagen, Denmark -
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4
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Early and Late Onset Side Effects of Photodynamic Therapy. Biomedicines 2018; 6:biomedicines6010012. [PMID: 29382133 PMCID: PMC5874669 DOI: 10.3390/biomedicines6010012] [Citation(s) in RCA: 78] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2017] [Revised: 01/20/2018] [Accepted: 01/25/2018] [Indexed: 01/06/2023] Open
Abstract
Photodynamic Therapy (PDT) is a non-invasive treatment successfully used for neoplastic, inflammatory and infectious skin diseases. One of its strengths is represented by the high safety profile, even in elderly and/or immuno-depressed subjects. PDT, however, may induce early and late onset side effects. Erythema, pain, burns, edema, itching, desquamation, and pustular formation, often in association with each other, are frequently observed in course of exposure to the light source and in the hours/days immediately after the therapy. In particular, pain is a clinically relevant short-term complication that also reduces long-term patient satisfaction. Rare complications are urticaria, contact dermatitis at the site of application of the photosensitizer, and erosive pustular dermatosis. Debated is the relationship between PDT and carcinogenesis: the eruptive appearance of squamous cell carcinoma (SCC) in previously treated areas has been correlated to a condition of local and/or systemic immunosuppression or to the selection of PDT-resistant SCC. Here we review the literature, with particular emphasis to the pathogenic hypotheses underlying these observations.
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Nissen C, Heerfordt I, Wiegell S, Mikkelsen C, Wulf H. Increased protoporphyrin IX accumulation does not improve the effect of photodynamic therapy for actinic keratosis: a randomized controlled trial. Br J Dermatol 2017; 176:1241-1246. [DOI: 10.1111/bjd.15098] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/23/2016] [Indexed: 01/04/2023]
Affiliation(s)
- C.V. Nissen
- Department of Dermatology; Bispebjerg Hospital; University of Copenhagen; Bispebjerg Bakke 23 DK-2400 Copenhagen NV Denmark
| | - I.M. Heerfordt
- Department of Dermatology; Bispebjerg Hospital; University of Copenhagen; Bispebjerg Bakke 23 DK-2400 Copenhagen NV Denmark
| | - S.R. Wiegell
- Department of Dermatology; Bispebjerg Hospital; University of Copenhagen; Bispebjerg Bakke 23 DK-2400 Copenhagen NV Denmark
| | - C.S. Mikkelsen
- Clinic of Dermatology; Bredgade 13 9700 Broenderslev Denmark
| | - H.C. Wulf
- Department of Dermatology; Bispebjerg Hospital; University of Copenhagen; Bispebjerg Bakke 23 DK-2400 Copenhagen NV Denmark
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Nissen CV, Wiegell SR, Philipsen PA, Wulf HC. Short-term chemical pretreatment cannot replace curettage in photodynamic therapy. PHOTODERMATOLOGY PHOTOIMMUNOLOGY & PHOTOMEDICINE 2016; 32:146-52. [DOI: 10.1111/phpp.12236] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 02/07/2016] [Indexed: 11/30/2022]
Affiliation(s)
- Christoffer V. Nissen
- Department of Dermatology; Bispebjerg Hospital; University of Copenhagen; Copenhagen NV Denmark
| | - Stine Regin Wiegell
- Department of Dermatology; Bispebjerg Hospital; University of Copenhagen; Copenhagen NV Denmark
| | - Peter Alshede Philipsen
- Department of Dermatology; Bispebjerg Hospital; University of Copenhagen; Copenhagen NV Denmark
| | - Hans Christian Wulf
- Department of Dermatology; Bispebjerg Hospital; University of Copenhagen; Copenhagen NV Denmark
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Neittaanmäki-Perttu N, Grönroos M, Karppinen T, Tani T, Snellman E. Hexyl-5-aminolaevulinate 0·2% vs. methyl-5-aminolaevulinate 16% daylight photodynamic therapy for treatment of actinic keratoses: results of a randomized double-blinded pilot trial. Br J Dermatol 2015; 174:427-9. [DOI: 10.1111/bjd.13924] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- N. Neittaanmäki-Perttu
- Department of Dermatology and Allergology; Helsinki University Central Hospital; Finland
- Department of Dermatology and Allergology; Päijät-Häme Social and Health Care Group; Lahti Finland
| | - M. Grönroos
- Department of Dermatology and Allergology; Päijät-Häme Social and Health Care Group; Lahti Finland
| | - T.T. Karppinen
- Department of Dermatology and Allergology; Päijät-Häme Social and Health Care Group; Lahti Finland
| | - T.T. Tani
- Department of Pathology; Päijät-Häme Social and Health Care Group; Lahti Finland
| | - E. Snellman
- Department of Dermatology; Tampere University and Tampere University Hospital; Finland
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Kanick SC, Davis SC, Zhao Y, Sheehan KL, Hasan T, Maytin EV, Pogue BW, Chapman MS. Pre-treatment protoporphyrin IX concentration in actinic keratosis lesions may be a predictive biomarker of response to aminolevulinic-acid based photodynamic therapy. Photodiagnosis Photodyn Ther 2015; 12:561-6. [PMID: 26480810 DOI: 10.1016/j.pdpdt.2015.10.006] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2015] [Revised: 09/14/2015] [Accepted: 10/12/2015] [Indexed: 01/23/2023]
Abstract
BACKGROUND Although aminolevulinic acid (ALA)-induced protoporphyrin IX (PpIX) photodynamic therapy (PDT) is an effective FDA-approved therapy for actinic keratosis (AK), a substantial fraction of patients (up to 25%) do not respond to treatment. This study examined the feasibility of using pre-treatment measurements of PpIX concentration in AK lesions to predict response of ALA-PpIX PDT. METHODS A non-invasive fiber-optic fluorescence spectroscopy system was used to measure PpIX concentration in patients undergoing standard-of-care ALA-PDT for AK. All patients provided assessments of pain at the time of treatment (n=70), and a subset reported pain and erythema 48-76 h after treatment (n=13). RESULTS PpIX concentration was significantly higher in lesions of patients reporting high levels of pain (VAS score ≥5) immediately after treatment vs. patients reporting pain scores below VAS=5 (p<0.022) (n=70). However, pain was not an exclusive indicator of PpIX concentration as many patients with low PpIX concentration reported high pain. In a subpopulation of patients surveyed in the days after treatment (n=13), PpIX concentration measured on the day of treatment was uncorrelated with pain-reported immediately after treatment (r=0.17, p<0.57), but positive correlations were found between PpIX concentration and patient-reported pain (r=0.55, p<0.051) and erythema (r=0.58, p<0.039) in the 48-72 h following treatment. CONCLUSIONS These data suggest that in vivo optical measurements of PpIX concentration acquired before light delivery may be an objective predictor of response to ALA-PpIX PDT. Identification of non-responding patients on the day of treatment could facilitate the use of interventions that may improve outcomes.
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Affiliation(s)
- S C Kanick
- Thayer School of Engineering, Dartmouth College, Hanover, USA; Norris Cotton Cancer Center, Dartmouth Hitchcock Medical Center, Lebanon NH, USA.
| | - S C Davis
- Thayer School of Engineering, Dartmouth College, Hanover, USA; Norris Cotton Cancer Center, Dartmouth Hitchcock Medical Center, Lebanon NH, USA
| | - Y Zhao
- Thayer School of Engineering, Dartmouth College, Hanover, USA
| | - K L Sheehan
- Department of Surgery, Dartmouth Hitchcock Medical Center, Lebanon, USA
| | - T Hasan
- Wellman Center for Photomedicine, Massachusetts General Hospital, Boston, USA
| | - E V Maytin
- Wellman Center for Photomedicine, Massachusetts General Hospital, Boston, USA; Biomedical Engineering, Cleveland Clinic, Cleveland, USA
| | - B W Pogue
- Thayer School of Engineering, Dartmouth College, Hanover, USA; Norris Cotton Cancer Center, Dartmouth Hitchcock Medical Center, Lebanon NH, USA; Department of Surgery, Dartmouth Hitchcock Medical Center, Lebanon, USA; Wellman Center for Photomedicine, Massachusetts General Hospital, Boston, USA
| | - M S Chapman
- Department of Surgery, Dartmouth Hitchcock Medical Center, Lebanon, USA
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Nissen CV, Philipsen PA, Wulf HC. Protoporphyrin IX formation after topical application of methyl aminolaevulinate and BF-200 aminolaevulinic acid declines with age. Br J Dermatol 2015; 173:760-6. [PMID: 25997508 DOI: 10.1111/bjd.13923] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/13/2015] [Indexed: 01/22/2023]
Abstract
BACKGROUND Topical photodynamic therapy (PDT) is a popular treatment modality in dermatology. The effect of PDT in epidermal cells depends on formation of protoporphyrin IX (PpIX) from 5-aminolevulinic acid (ALA). A variety of physiological changes in epidermal function occur with increasing age, but no studies have investigated whether PpIX formation is age-related. OBJECTIVES To investigate a possible relationship between age and PpIX formation. METHODS Methyl aminolaevulinate cream (MAL) and 5-ALA gel (BF-200 ALA) were applied to two identical fields on the forearm of 30 healthy volunteers for 24 h. The volunteers were divided into two age groups: a young group under 55 years (range 18-54) and an older group over 55 years (range 65-85). PpIX formation was measured noninvasively every hour from 1-5 h, and after 18, 21 and 24 h. Skin phototype, stratum corneum hydration and ultraviolet (UV) damage were also assessed. Treatment efficacy in relation to age was evaluated in 100 basal cell carcinomas (BCCs) treated with MAL-PDT. RESULTS Both photosensitizers induced significantly more PpIX formation in the younger group. Linear regression revealed a significant age-related decline in PpIX formation after the standard application time of 3 h (P < 0.001 for both treatments). Skin phototype, stratum corneum hydration and UV damage were not associated with PpIX formation. The treatment efficacy of BCCs 3 months after MAL-PDT was higher in young patients (P = 0.012). CONCLUSIONS PpIX formation in human skin declines with age. No explanation could be attributed to skin phototype, stratum corneum hydration or UV damage. The consequence might be reduced efficacy of PDT in the elderly.
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Affiliation(s)
- C V Nissen
- Department of Dermatology, Bispebjerg Hospital, University of Copenhagen, Bispebjerg Bakke 23, DK-2400, Copenhagen NV, Denmark
| | - P A Philipsen
- Department of Dermatology, Bispebjerg Hospital, University of Copenhagen, Bispebjerg Bakke 23, DK-2400, Copenhagen NV, Denmark
| | - H C Wulf
- Department of Dermatology, Bispebjerg Hospital, University of Copenhagen, Bispebjerg Bakke 23, DK-2400, Copenhagen NV, Denmark
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Lerche CM, Fabricius S, Philipsen PA, Wulf HC. Correlation between treatment time, photobleaching, inflammation and pain after photodynamic therapy with methyl aminolevulinate on tape-stripped skin in healthy volunteers. Photochem Photobiol Sci 2015; 14:875-82. [DOI: 10.1039/c5pp00069f] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A shorter incubation time with methyl aminolevulinate in healthy volunteers results in decreased photobleaching and also less inflammation and pain.
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Affiliation(s)
| | - Susanne Fabricius
- Department of Dermatology
- Copenhagen University Hospital
- Copenhagen
- Denmark
| | - Peter A. Philipsen
- Department of Dermatology
- Copenhagen University Hospital
- Copenhagen
- Denmark
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11
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Togsverd-Bo K, Lerche CM, Philipsen PA, Hædersdal M, Wulf HC. Artificial daylight photodynamic therapy with "non-inflammatory" doses of hexyl aminolevulinate only marginally delays SCC development in UV-exposed hairless mice. Photochem Photobiol Sci 2014; 12:2130-6. [PMID: 24064675 DOI: 10.1039/c3pp50152c] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Photodynamic therapy (PDT) is effective for actinic keratoses, but is associated with pain and post-treatment inflammation. Daylight-mediated PDT and PpIX-precursors at low concentrations reduce pain and inflammation intensity. The objective was to evaluate the effect of repeated low-concentration PDT combined with artificial daylight on SCC development. Mice (n = 265) were exposed to simulated solar UV-irradiation (UVR) 3 times weekly mimicking "summer-dose"-exposure (3 SED). Selected groups of mice received a "winter-dose"-exposure (0.6 SED) for the first 90 days. PDT was delivered with 0.1%, 0.05% and 0.02% hexyl aminolevulinate (HAL) cream and artificial daylight for 2.5 hours (6 J cm(-2)) in different treatment regimes (1-3 times weekly, 45-days intervals, days 1-180 and from day 180 onwards). The primary end-point was the time to first SCC (1 mm diameter). 0.1% HAL-PDT given 3 times weekly slightly delayed SCC development and induced minimal inflammation. In winter- and summer UVR-treatment regimes, 0.1% HAL PDT delayed the time to first SCC compared to control UVR and placebo-PDT when mice were PDT-treated on days 1-180 (median 213 vs. 199 days, p = 0.011) and from day 180 onwards (median 218 vs. 199 days, p = 0.006). PDT with 0.05% and 0.02% HAL did not influence SCC development (medians 206 days, p = ns). In summer UVR-exposed mice, 0.1% HAL-PDT marginally postponed the time to first SCC compared to control UVR (median 160 days) when treatments were given 3 times weekly for 180 days (median 166, p = 0.01), but not for 90 days (median 161, p = 0.112). In conclusion, repeated low-concentration HAL-PDT combined with artificial daylight is well-tolerated, but only marginally delays SCC development in mice.
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Mallidi S, Anbil S, Lee S, Manstein D, Elrington S, Kositratna G, Schoenfeld D, Pogue B, Davis SJ, Hasan T. Photosensitizer fluorescence and singlet oxygen luminescence as dosimetric predictors of topical 5-aminolevulinic acid photodynamic therapy induced clinical erythema. JOURNAL OF BIOMEDICAL OPTICS 2014; 19:028001. [PMID: 24503639 PMCID: PMC3915169 DOI: 10.1117/1.jbo.19.2.028001] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2013] [Revised: 12/05/2013] [Accepted: 12/05/2013] [Indexed: 05/19/2023]
Abstract
The need for patient-specific photodynamic therapy (PDT) in dermatologic and oncologic applications has triggered several studies that explore the utility of surrogate parameters as predictive reporters of treatment outcome. Although photosensitizer (PS) fluorescence, a widely used parameter, can be viewed as emission from several fluorescent states of the PS (e.g., minimally aggregated and monomeric), we suggest that singlet oxygen luminescence (SOL) indicates only the active PS component responsible for the PDT. Here, the ability of discrete PS fluorescence-based metrics (absolute and percent PS photobleaching and PS re-accumulation post-PDT) to predict the clinical phototoxic response (erythema) resulting from 5-aminolevulinic acid PDT was compared with discrete SOL (DSOL)-based metrics (DSOL counts pre-PDT and change in DSOL counts pre/post-PDT) in healthy human skin. Receiver operating characteristic curve (ROC) analyses demonstrated that absolute fluorescence photobleaching metric (AFPM) exhibited the highest area under the curve (AUC) of all tested parameters, including DSOL based metrics. The combination of dose-metrics did not yield better AUC than AFPM alone. Although sophisticated real-time SOL measurements may improve the clinical utility of SOL-based dosimetry, discrete PS fluorescence-based metrics are easy to implement, and our results suggest that AFPM may sufficiently predict the PDT outcomes and identify treatment nonresponders with high specificity in clinical contexts.
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Affiliation(s)
- Srivalleesha Mallidi
- Massachusetts General Hospital, Wellman Center for Photomedicine, Boston, Massachusetts 02114
| | - Sriram Anbil
- Massachusetts General Hospital, Wellman Center for Photomedicine, Boston, Massachusetts 02114
| | - Seonkyung Lee
- Physical Sciences Inc., Andover, Massachusetts 01810
| | - Dieter Manstein
- Massachusetts General Hospital, Department of Dermatology, Boston, Massachusetts 02114
| | - Stefan Elrington
- Massachusetts General Hospital, Wellman Center for Photomedicine, Boston, Massachusetts 02114
| | - Garuna Kositratna
- Massachusetts General Hospital, Department of Dermatology, Boston, Massachusetts 02114
| | - David Schoenfeld
- Massachusetts General Hospital, Biostatistics Department, Boston, Massachusetts 02114
| | - Brian Pogue
- Dartmouth College, Thayer School of Engineering, Hanover, New Hampshire 03755
| | | | - Tayyaba Hasan
- Massachusetts General Hospital, Wellman Center for Photomedicine, Boston, Massachusetts 02114
- Address all correspondence to: Tayyaba Hasan, E-mail:
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13
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Kanick SC, Davis SC, Zhao Y, Hasan T, Maytin EV, Pogue BW, Chapman MS. Dual-channel red/blue fluorescence dosimetry with broadband reflectance spectroscopic correction measures protoporphyrin IX production during photodynamic therapy of actinic keratosis. JOURNAL OF BIOMEDICAL OPTICS 2014; 19:75002. [PMID: 24996661 PMCID: PMC4082494 DOI: 10.1117/1.jbo.19.7.075002] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2014] [Accepted: 05/27/2014] [Indexed: 05/10/2023]
Abstract
Dosimetry for aminolevulinic acid (ALA)-induced protoporphyrin IX (PpIX) photodynamic therapy of actinic keratosis was examined with an optimized fluorescence dosimeter to measure PpIX during treatment. While insufficient PpIX generation may be an indicator of incomplete response, there exists no standardized method to quantitate PpIX production at depths in the skin during clinical treatments. In this study, a spectrometer-based point probe dosimeter system was used to sample PpIX fluorescence from superficial (blue wavelength excitation) and deeper (red wavelength excitation) tissue layers. Broadband white light spectroscopy (WLS) was used to monitor aspects of vascular physiology and inform a correction of fluorescence for the background optical properties. Measurements in tissue phantoms showed accurate recovery of blood volume fraction and reduced scattering coefficient from WLS, and a linear response of PpIX fluorescence versus concentration down to 1.95 and 250 nM for blue and red excitations, respectively. A pilot clinical study of 19 patients receiving 1-h ALA incubation before treatment showed high intrinsic variance in PpIX fluorescence with a standard deviation/mean ratio of > 0.9. PpIX fluorescence was significantly higher in patients reporting higher pain levels on a visual analog scale. These pilot data suggest that patient-specific PpIX quantitation may predict outcome response.
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Affiliation(s)
- Stephen Chad Kanick
- Thayer School of Engineering, Dartmouth College, Hanover, New Hampshire 03755
- Address all correspondence to: Stephen Chad Kanick, E-mail:
| | - Scott C. Davis
- Thayer School of Engineering, Dartmouth College, Hanover, New Hampshire 03755
| | - Yan Zhao
- Thayer School of Engineering, Dartmouth College, Hanover, New Hampshire 03755
| | - Tayyaba Hasan
- Wellman Center for Photomedicine, Massachusetts General Hospital, Boston, Massachusetts 02114
| | | | - Brian W. Pogue
- Thayer School of Engineering, Dartmouth College, Hanover, New Hampshire 03755
- Wellman Center for Photomedicine, Massachusetts General Hospital, Boston, Massachusetts 02114
- Department of Surgery, Section of Dermatology, Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire 03766
| | - M. Shane Chapman
- Department of Surgery, Section of Dermatology, Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire 03766
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