Qatar Phototherapy (TL01) Treatment Protocol

Indications:

• Psoriasis vulgaris
• Vitiligo
• Atopic dermatitis
• Pruritus (idiopathic, Uremic and cholestatic)
• Generalized lichen planus
• pityriasis lichenoides acuta and chronica
• Photodermatoses (Polymorphous light eruption (PMLE), erythropoietic protoporphyria, actinic prurigo, and solar urticaria)
• Perforating dermatosis
• CTCL
• Lymphomatoid papulosis
• pityriasis rubra pilaris
• Palmoplantar pustulosis
• Urticaria pigmentosa
• Cutaneous GVHD
• Generalized granuloma annulare
• Prurigo nodularis
• Localized morphea & pansclerotic morphea

References:

1. Olsen EA, Hodak E, Anderson T, Carter JB, Henderson M, Cooper K, Lim HW. Guidelines for phototherapy of mycosis fungoides and Sézary syndrome: A consensus statement of the United States Cutaneous Lymphoma Consortium. J Am Acad Dermatol. 2016 Jan;74(1):27-58. doi: 10.1016/j.jaad.2015.09.033. Epub 2015 Nov 4. PMID: 26547257.
2. Davis DMR, Drucker AM, Alikhan A, Bercovitch L, Cohen DE, Darr JM, Eichenfield LF, Frazer-Green L, Paller AS, Schwarzenberger K, Silverberg JI, Singh AM, Wu PA, Sidbury R. Guidelines of care for the management of atopic dermatitis in adults with phototherapy and systemic therapies. J Am Acad Dermatol. 2024 Feb;90(2):e43-e56. doi: 10.1016/j.jaad.2023.08.102. Epub 2023 Nov 7. PMID: 37943240.

References for Psoriasis Protocol:

1. Elmets CA, Lim HW, Stoff B, Connor C, Cordoro KM, Lebwohl M, Armstrong AW, Davis DMR, Elewski BE, Gelfand JM, Gordon KB, Gottlieb AB, Kaplan DH, Kavanaugh A, Kiselica M, Kivelevitch D, Korman NJ, Kroshinsky D, Leonardi CL, Lichten J, Mehta NN, Paller AS, Parra SL, Pathy AL, Farley Prater EA, Rupani RN, Siegel M, Strober BE, Wong EB, Wu JJ, Hariharan V, Menter A. Joint American Academy of Dermatology-National Psoriasis Foundation guidelines of care for the management and treatment of psoriasis with phototherapy. J Am Acad Dermatol. 2019 Sep;81(3):775-804. doi: 10.1016/j.jaad.2019.04.042. Epub 2019 Jul 25. Erratum in: J Am Acad Dermatol. 2020 Mar;82(3):780. doi: 10.1016/j.jaad.2019.11.024. PMID: 31351884.
2. Phototherapy Guidelines. Phototherapy Support. 2020. https://www.phototherapysupport.net/wp-content/uploads/2020/01/Phototherapy-Guidelines.pdf
3. Phototherapy Guidance and Service Standards 2022. British Association of Dermatologists; 2022. https://cdn.bad.org.uk/uploads/2022/09/14144343/Phototherapy-Guidance-and-Services-Standards-2022.pdf.

References for Atopic Dermatitis:

1. Sidbury R, Davis DM, Cohen DE, Cordoro KM, Berger TG, Bergman JN, Chamlin SL, Cooper KD, Feldman SR, Hanifin JM, Krol A, Margolis DJ, Paller AS, Schwarzenberger K, Silverman RA, Simpson EL, Tom WL, Williams HC, Elmets CA, Block J, Harrod CG, Begolka WS, Eichenfield LF; American Academy of Dermatology. Guidelines of care for the management of atopic dermatitis: section 3. Management and treatment with phototherapy and systemic agents. J Am Acad Dermatol. 2014 Aug;71(2):327-49. doi: 10.1016/j.jaad.2014.03.030. Epub 2014 May 9. PMID: 24813298; PMCID: PMC4410179.
2. Davis DMR, Drucker AM, Alikhan A, Bercovitch L, Cohen DE, Darr JM, Eichenfield LF, Frazer-Green L, Paller AS, Schwarzenberger K, Silverberg JI, Singh AM, Wu PA, Sidbury R. Guidelines of care for the management of atopic dermatitis in adults with phototherapy and systemic therapies. J Am Acad Dermatol. 2024 Feb;90(2):e43-e56. doi: 10.1016/j.jaad.2023.08.102. Epub 2023 Nov 7. PMID: 37943240.

Protocol Details

• Compared to NB-UVB phototherapy (311-313nm), the excimer laser appears to augment and expedite the re-pigmentation process. In addition, excimer laser enhances and accelerates the pigmentation process to a greater extent than NB-UVB phototherapy. Excimer laser and lamp treatments are equally effective or even more superior compared to NB-UVB.
• Excimer lamps or laser is indicated for segmental vitiligo and stable localized non-segmental vitiligo.
• Combination therapy of Excimer laser and topical calcineurin inhibitors was more effective than Excimer laser monotherapy.
• Lesions on the face,  neck, and trunk respond to a greater extent than lesions on extremities. Lesions on hands and feet tend to have the least favorable prognosis.
• Increase the UVB dose according to the following guidelines until the patient reports slight erythema within 24 hours after treatment.
• Maximal dose per session: Face: 1000 mJ/cm² and for the Body: 2500--3000 mJ/cm²
• Patient should be evaluated after 30 sessions of Excimer laser with the treating physician.
• Excimer laser treatment should be avoided around periocular area without ocular shield.

References:

1. Bae, J, Hong, B, Lee, J, Lee, J, Kim, G. The efficacy of 308-nm excimer laser/light (EL) and topical agent combination therapy versus EL monotherapy for vitiligo: A systematic review and meta-analysis of randomized controlled trials (RCTs).  J Am Acad Dermatol. 2016;74(5):907-915. doi:10.1016/j.jaad.2015.11.044.
2. Nicolaidou, E, Antoniou, C, Stratigos, A, Katsambas, A. Narrowband ultraviolet B phototherapy and 308-nm excimer laser in the treatment of vitiligo: A review.  J Am Acad Dermatol. 2009;60(3):470-477. Cited in: Your Journals@Ovid Full Text at https://ovidsp.ovid.com/ovidweb.cgi?T=JS&PAGE=reference&D=yrovftj&NEWS=N&AN=00004725-200903000-00015. Accessed December 24, 2025.

Protocol Details

• Hands: Palms and backs of hands can be treated together or separately. Fingers should be spread in the center of the unit. Cuffs should also be used to protect the untreated areas.
• Feet: Can be treated at the same time as hands or separately. Feet should be in the Centre of the unit.
• Starting Dose: No MED is required. Give 0.39J cm2 as a starting dose unless otherwise decided by doctor.
• Increment Regimen - increments will be given at each visit based on a percentage of the previous dose and erythema response.
• Referred to erythema grading table below for dose increment guidance.
• In patients with pigmented skin, erythema and edema may not be seen, but the patient may complain of heat and skin tightness. Dose should be adjusted.
• If patient develops itch, encourage use of prescribed topical steroids and emollients. If persistent, review by doctor.
• If patient cancels/misses treatment -- See missed treatment protocol.
• Discharge - See discharge protocol.

Phototherapy with Retinoids -- Acitretin

• Recommended acitretin Dosage: 10 -- 25mg/day.
• Standard phototherapy entails 2 - 3 sessions per week for a period of 12 weeks to achieve therapeutic results.
• Oral Retinoids decrease the thickness of the epidermis, enhancing UV penetration and causing a more brisk response to UV exposure.
• Oral retinoids can be effectively used in combination with NB-UVB to enhance therapeutic outcomes.
• The onset of action of Acitretin alone may not be observed until 1 -- 3 months after initiation.
• The lowest effective dose of acitretin should be used to reduce retinoid-related adverse effects such as cheilitis, dry mouth, and dry skin.
• Concomitant use of oral retinoids therapy reduces the number of phototherapy sessions required to achieve clearance. And lowers the cumulative UVB dose, potentially minimizing long-term ultraviolet exposure.
• Oral retinoids are non-immunosuppressive and relatively safe and suitable for selected patients undergoing phototherapy.
• Acitretin has a protective role in reducing the risk of non-melanoma skin cancers associated with long-term UVB or PUVA phototherapy.
• Recommended to start low-dose acitretin as a single agent for 2 weeks. UVB treatments are then added to the regimen. Doses of UVB or UVA should be reduced by 50% and fewer phototherapy visits are typically required.
• In patients not responding adequately to NB-UVB, acitretin may be added during treatment. A temporary 50% reduction in the NB-UVB dose should be implemented for two weeks to minimize the risk of retinoid-associated phototoxicity.
• Acitretin** **is not recommended for women of childbearing age who wish to become pregnant during or within 3 years following discontinuation of treatment. For women of childbearing age, two negative pregnancy tests prior to initiating acitretin treatment and monthly tests thereafter are required.

Phototherapy with Retinoids -- Bexarotene

• Recommended bexarotene Dose: 75 -- 300 mg/day -- taken with a meal.
• Pregnancy prevention must be followed by all females of childbearing potential 1 month before starting, throughout and 1 month after cessation of treatment. All men should also use effective contraception measure for the same time period.
• Bexarotene used for Mycosis Fungoides stage: IA -- IB and IIA (Patches/Thin plaques).
• start slow with 10% at each irradiation session and increase slowly as patient tolerated.
• Avoid UV radiation at peak plasma concentrations which is 2 hours after ingestion of bexarotene.
• Maximum dose/session: 1.6 -- 2.0 J/cm2.
• phototherapy in combination with oral Bexarotene used to control disease progression in patients with early-stage MF. In cases of inadequate response to phototherapy alone, retinoids can be added to the treatment regimen which lead to a higher response rate and skin resolution compared to monotherapy
• Be aware of drug adverse effects that include neutropenia, anemia, hyperlipidemia, hypertriglyceridemia, hypothyroidism and hypercholesterolemia were blood monitoring is essential.
• Avoid concomitant use of medications that inhibit CYP3A4, such as erythromycin, ketoconazole, itraconazole, and clarithromycin, as these drugs may increase bexarotene plasma levels.

Phototherapy with cyclosporine

• The simultaneous use of NB-UVB and cyclosporine is contraindicated because of the increased likelihood of skin cancer
• Studies demonstrating the increased rate of photocarcinogenesis when cyclosporine is used in conjunction with PUVA.
• Cyclosporine is not recommended for use in combination with NB-UVB given the lack of significant supporting evidence and likely increased risk of nonmelanoma skin cancer secondary to immunosuppression and UV exposure.

Phototherapy with methotrexate

• Recommended methotrexate dosage: 7.5 -- 30 mg weekly
• Methotrexate can be used as a systemic adjunct to NB-UVB phototherapy in patients with moderate-to-severe plaque psoriasis.
• Combination therapy with methotrexate and NB-UVB achieves clearance rates comparable to methotrexate or NB-UVB monotherapy.
• Patients receiving combination therapy generally require fewer weeks of treatment to achieve disease clearance.
• Use of combination therapy results in a lower number of NB-UVB treatment sessions and a reduced cumulative UVB dose.
• Clinically significant interactions may occur when methotrexate is used concurrently with other medications. These include cyclosporine, azathioprine, sulfasalazine, NSAIDs, tetracyclines and live vaccines.
• Combination therapy is associated with higher PASI response rates, including PASI 75, achieved in a shorter treatment duration.
• Erythema and pruritus may occur more frequently with combination therapy compared with NB-UVB monotherapy.
• Gastrointestinal adverse effects may be reduced due to lower cumulative methotrexate exposure in combination regimens.
• Methotrexate is contraindicated in pregnancy and lactation, and it is advised to be stopped 3 months before conception.
• Overall, the combination of methotrexate and NB-UVB allows faster disease control while minimizing cumulative systemic and ultraviolet exposure.
• Methotrexate may increase the risk of phototoxic reactions when combined with phototherapy; therefore, dosing should be scheduled on a weekend to maximize the interval before the next session and reduce phototoxicity risk.

Phototherapy and biological treatment

• Combination therapy with NB-UVB and biologic agents is supported by the literature and is recommended when monotherapy with either modality is insufficient.
• Adding NB-UVB to biologic therapy can significantly improve clinical outcomes, including higher rates of PASI 75, PASI 90, and complete clearance.
• Studies demonstrate that patients unresponsive to NB-UVB or biologic monotherapy alone may achieve meaningful improvement when both treatments are combined.
• Combination treatment with etanercept and NB-UVB has been associated with higher PASI response rates and greater histologic improvement compared with biologic therapy alone.
• Concomitant use of adalimumab and NB-UVB has shown high rates of PASI 75 and PASI 90, with sustained responses in a significant proportion of patients.
• Similar enhanced efficacy has been observed when NB-UVB is combined with ustekinumab, with superior clinical response in UV-treated areas.
• NB-UVB may act as an effective adjunct to biologics, potentially accelerating response and improving disease control in moderate-to-severe psoriasis with mild-to-moderate UV-related erythema being the most common adverse effect.

Phototherapy with Apremilast (Otezla)

• Apremilast, an oral PD-4 inhibitor, can be used in combination with NB-UVB.
• Avoid Apremilast in pregnancy, breastfeeding and children below 18 years old.
• Combination treatment with apremilast (30 mg twice daily) and NB-UVB three times weekly has demonstrated good efficacy in patients with psoriasis.
• In clinical studies, a majority of patients completing combination therapy achieved meaningful clinical improvement, including PASI 75.
• Combination therapy was generally well tolerated, with no unexpected safety concerns reported.The most common adverse events were mild to moderate erythema related to phototherapy.
• Retrospective data further support the safe use of apremilast in combination with NB-UVB in patients with inadequate response to phototherapy alone.
• Apremilast represents a useful systemic adjunct to NB-UVB for patients requiring combination therapy with a favorable safety profile.

Phototherapy with JAKs inhibitors

• Systemic JAK inhibitors may enhance vitiligo repigmentation when combined with phototherapy, particularly NB-UVB.
• Immunologic suppression alone may not be sufficient for repigmentation, as melanocyte recovery appears to require concomitant light stimulation.
• Repigmentation achieved with phototherapy may potentially be maintained with JAK inhibitor monotherapy once melanocyte regeneration is established.
• Case reports have demonstrated successful repigmentation with oral baricitinib combined with NB-UVB phototherapy.
• Ritlecitinib has shown clinical benefit in vitiligo, with superior outcomes observed when combined with NB-UVB compared with ritlecitinib monotherapy.
• In patients with suboptimal response to ritlecitinib alone, the addition of NB-UVB significantly improved both facial and total body VASI scores.
• Combination therapy with systemic JAK inhibitors and NB-UVB resulted in higher rates of meaningful clinical improvement and better patient-reported outcomes.
• Current evidence supports a synergistic effect between phototherapy and systemic JAK inhibitors; however, further research is needed to better define long-term safety and optimal combination strategies with systemic immunomodulatory agents.

References for Combination Therapy:

• Bishnoi, Anuradha1; Hamzavi, Iltefat2. Phototherapy in vitiligo. Pigment International 11(3):p 151-166, September-December 2024. | DOI: 10.4103/pigmentinternational_52_24.
• Elmets CA et al. Joint AAD--NPF guidelines for the management and treatment of psoriasis with phototherapy. J Am Acad Dermatol. 2019;81(3):775--804.
• Myers E, Kheradmand S, Miller R. An Update on Narrowband Ultraviolet B Therapy for the Treatment of Skin Diseases. Cureus. 2021 Nov 1;13(11):e19182. doi: 10.7759/cureus.19182. PMID: 34873522; PMCID: PMC8634827.
• Arora S, Das P, Arora G. Systematic Review and Recommendations to Combine Newer Therapies With Conventional Therapy in Psoriatic Disease. Front Med (Lausanne). 2021 Aug 19;8:696597. doi: 10.3389/fmed.2021.696597. PMID: 34490293; PMCID: PMC8416676.
• Morita A, Tateishi C, Ikumi K, Hayashi D, Nakada A, Nishihara H, Torii K, Nishida E, Tsuruta D. Comparison of the Efficacy and Safety of Bexarotene and Photo(Chemo)Therapy Combination Therapy and Bexarotene Monotherapy for Cutaneous T-Cell Lymphoma. Dermatol Ther (Heidelb). 2022 Mar;12(3):615-629. doi: 10.1007/s13555-021-00655-0. Epub 2022 Jan 27. PMID: 35084694; PMCID: PMC8941067.
• Goulden V, Ling TC, Babakinejad P, Dawe R, Eadie E, Fassihi H, Fityan A, Garibaldinos T, Ibbotson SH, Novakovic L, Rush E, Weatherhead SC, Whitehouse H, Hashme M, Mohd Mustapa MF, Exton LS; British Association of Dermatologists' Clinical Standards Unit. British Association of Dermatologists and British Photodermatology Group guidelines for narrowband ultraviolet B phototherapy 2022. Br J Dermatol. 2022 Sep;187(3):295-308. doi: 10.1111/bjd.21669. Epub 2022 Jul 3. PMID: 35604545.

Protocol 5 : NB-UVB use in pregnancy and lactation

• NB-UVB phototherapy is generally considered safe during pregnancy when clinically indicated.
• High cumulative NB-UVB exposure may result in a reduction in folic acid levels due to photodegradation, particularly with prolonged full-body treatment courses.
• Significant folate reduction has been reported after high cumulative NB-UVB doses (e.g. approximately 36 treatment sessions).
• Measurement of folic acid levels may be considered in women planning pregnancy, with or without supplementation.
• Folate supplementation should be considered in women of childbearing age receiving prolonged NB-UVB courses (e.g. more than 30 treatments).
• The need for folic acid supplementation should be reinforced in women receiving NB-UVB during the first trimester of pregnancy.
• Use of facial shielding during treatment may help reduce the risk of melasma exacerbation during pregnancy.
• NB-UVB can be safely used in breastfeeding women, with no known adverse effects on lactation or the infant.

References:

• Shirzadian Kebria A, Hosseini M, Khafri S. The effect of narrowband ultraviolet B phototherapy on serum folate level. Caspian J Intern Med. 2021 Mar;12(2):180-183. doi: 10.22088/cjim.12.2.180. PMID: 34012536; PMCID: PMC8111802.
• El-Saie LT, Rabie AR, Kamel MI, Seddeik AK, Elsaie ML. Effect of narrowband ultraviolet B phototherapy on serum folic acid levels in patients with psoriasis. Lasers Med Sci. 2011 Jul;26(4):481-5. doi: 10.1007/s10103-011-0895-0. Epub 2011 Feb 23. PMID: 21344249.
• Olsen EA, Hodak E, Anderson T, Carter JB, Henderson M, Cooper K, Lim HW. Guidelines for phototherapy of mycosis fungoides and Sézary syndrome: A consensus statement of the United States Cutaneous Lymphoma Consortium. J Am Acad Dermatol. 2016 Jan;74(1):27-58. doi: 10.1016/j.jaad.2015.09.033. Epub 2015 Nov 4. PMID: 26547257.
• Dogra S, Mahajan R. Phototherapy for mycosis fungoides. Indian J Dermatol Venereol Leprol. 2015 Mar-Apr;81(2):124-35. doi: 10.4103/0378-6323.152169. PMID: 25751327.

Protocol 6 : NB-UVB use in children

• NB-UVB has demonstrated good efficacy, tolerability, and short-term safety in children across multiple retrospective studies.
• There is no defined minimum age for NB-UVB treatment; however, children must be able to stand alone in the phototherapy cabinet and comply with safety measures, including eye protection, which is generally feasible from around 6 years of age.
• Long-term safety data are limited, but available evidence suggests a low incidence of skin cancer in individuals treated with NB-UVB during childhood.
• NB-UVB is effective in childhood psoriasis, supported by systematic reviews and retrospective studies, and represents a useful treatment option for moderate-to-severe disease.
• NB-UVB is effective in moderate, severe, and chronic atopic dermatitis in children and is recommended as a second-line therapy for severe cases in children under 12 years of age.
• NB-UVB may be beneficial in selected childhood photodermatoses, including polymorphic light eruption, erythropoietic protoporphyria, and, to a lesser extent, actinic prurigo and hydroa vacciniforme.
• NB-UVB is an effective treatment option for early-stage mycosis fungoides in children and young adults, either as monotherapy or in combination with topical corticosteroids.
• Treatment-related anxiety in children can usually be managed through clear explanation, pretreatment visits, child-specific information leaflets, and parental support during therapy.

References:

• Benavides E, Hartmann D, Retamal C, Valenzuela F. The role of phototherapy in pediatric dermatology. An Bras Dermatol. 2025 Dec 26;101(1):501252. doi: 10.1016/j.abd.2025.501252. Epub ahead of print. PMID: 41483505.
• Yazici S, Günay B, Başkan EB, Aydoğan K, Saricaoğlu H, Tunali Ş. The efficacy of narrowband UVB treatment in pediatric vitiligo: a retrospective analysis of 26 cases. Turk J Med Sci. 2017 Apr 18;47(2):381-384. doi: 10.3906/sag-1512-59. PMID: 28425237.
• Bouceiro Mendes R, Alpalhão M, Filipe P. UVB phototherapy in the treatment of vitiligo: State of the art and clinical perspectives. Photodermatol Photoimmunol Photomed. 2022 May;38(3):215-223. doi: 10.1111/phpp.12740. Epub 2021 Oct 16. PMID: 34626483.

Contraindications to Phototherapy

Absolute Contraindications

• Photogenodermatoses, including xeroderma pigmentosum, Cockayne syndrome, trichothiodystrophy, Bloom syndrome, and Rothmund--Thomson syndrome.
• Disorders with a genetic predisposition to skin cancers, including Gorlin syndrome and albinism.
• Concomitant use of oral immunosuppressive medications, particularly ciclosporin, azathioprine, mycophenolate mofetil, and tacrolimus. NB-UVB may be considered with caution in selected patients receiving methotrexate or biologic therapies following careful risk--benefit assessment.
• Patients who are medically unfit or unable to safely stand in a whole-body NB-UVB unit (e.g. severe cardiovascular or respiratory disease, poorly controlled epilepsy).

Relative Contraindications

• Hereditary dysplastic naevus syndrome.
• Lupus erythematosus.
• Previous exposure to arsenic or ionizing radiation.
• Past excessive exposure to natural sunlight, sunbeds, or phototherapy.
• Previous significant use of oral immunosuppressive medications (ciclosporin, azathioprine, mycophenolate mofetil, tacrolimus).
• Current premalignant skin lesions.
• Current or past history of non-melanoma skin cancer.
• Current or past history of melanoma.
• Strong family history of melanoma or non-melanoma skin cancer at a young age.

Special Considerations

• NB-UVB should generally be avoided in patients with a personal history of melanoma or with current melanoma or non-melanoma skin cancer. Individual risk--benefit assessment is required, and treatment may be considered when therapeutic options are limited.
• NB-UVB may be administered with caution in dermatoses that can be photoaggravated, including dermatomyositis, photoaggravated eczema, Darier disease, transient acantholytic dermatoses, pityriasis rubra pilaris, and active herpes simplex.

Phototherapy Erythema Grading and Management

• On the visit, examine the patient and take a history including erythema degree, pain, or pruritis since last phototherapy session.
• A Face shield should be worn unless otherwise indicated, to reduce the risk of ocular toxicity.
• Patients susceptible to cold sores - Herpes labialis (HSV) should wear a face shield and apply lip sunscreen throughout duration of treatment. If started it must be continued for all future UV sessions.
• If a patient develops an itch (pruritic), encourage use of emollients and antihistamines. If persistent, review by the doctor.

Adverse Effects of Phototherapy

General Safety

NB-UVB is considered a safe treatment modality with a relatively low risk of adverse effects.

Short-Term Adverse Effects

• Erythema is the most common adverse effect and is graded from E0 (no erythema) to E4 (painful erythema with bullae); severe reactions are uncommon.
• Erythema typically appears within 3--5 hours, peaks at 12--24 hours, and resolves within 72 hours.
• NB-UVB may exacerbate lupus erythematosus; autoantibody screening should be considered in at-risk individuals.
• Reactivation of herpes simplex virus (including HSV keratitis) may occur; consider prophylactic antivirals and facial shielding in susceptible patients.
• Pruritus is common and may relate to the underlying dermatosis.
• Rare blistering confined to psoriatic plaques has been reported.
• Hypopigmented macules and freckling (idiopathic guttate hypomelanosis--like) have been described.

Delayed Adverse Effects

• Photoageing, including coarse wrinkling and cutaneous atrophy, may occur with cumulative UV exposure.
• Current evidence does not demonstrate a significant increased risk of skin cancer with NB-UVB compared with PUVA.
• Long-term safety data for very high cumulative exposure (e.g. vitiligo patients) are limited; regular clinical review is advised.
• More than 500 lifetime UVB exposures should prompt consideration of skin cancer screening; treatment beyond this may be considered after consultant assessment.
• Male genitalia should be shielded during treatment to minimize theoretical cancer risk.
• Ocular exposure may cause acute and chronic photodamage; UV-protective goggles are mandatory during treatment.