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PubMed2004

Change of bilirubin photoisomers in the urine and serum before and after phototherapy compared with light source.

BACKGROUND: The clinical effect of phototherapy for neonatal hyperbilirubinemia is based on the production and elimination of cyclobilirubin. Generally, the clinical effect of light sources is estimated by the reduction in the total serum bilirubin level. One procedure with less invasiveness than blood collecting is urine collection. Whether the effectiveness of light sources used for phototherapy could be assessed using measurements of bilirubin photoisomers in urine was studied. METHODS: This study was a retrospective analysis of 38 term infants with hyperbilirubinemia who underwent phototherapy. Bilirubin fractions in serum and urine before and 24 h after the phototherapy were measured by high-performance liquid chromatography. The light sources used for the phototherapy were blue-white light (n = 11), Biliblanket plus high output (n = 13) or green light (n = 14). The relationships between serum and urine bilirubin photoisomers after phototherapy and whether the levels of urine bilirubin photoisomer are affected by the light sources with different wavelength characteristic were analyzed. RESULTS: There was no correlation between serum (ZE)-bilirubin and urine configurational isomers, but a weak positive correlation between serum (EZ)-cyclobilirubin and urine structural isomers after phototherapy. Although serum (ZE)-bilirubin levels depended on the wavelength characteristic of each light source during phototherapy, the urine configurational isomer levels did not depend on it. The increase in serum (EZ)-cyclobilirubin levels and the urine structural isomer levels were mostly in agreement. CONCLUSIONS: The urine bilirubin structural isomers may be used to estimate the serum (EZ)-cyclobilirubin levels and to evaluate the clinical effects of light sources.

Bilirubin↗

PubMed1996

Fibreoptic phototherapy in the management of jaundice in low birthweight neonates.

A fibreoptic phototherapy device has been compared with conventional white and special blue fluorescent phototherapy lamps to evaluate its efficacy in lowering serum bilirubin levels in low-birthweight neonates. Fibreoptic phototherapy was found to be as effective as white light and less effective than blue light, as assessed by (i) the bilirubin concentration after 24 h of phototherapy and at the end of phototherapy, (ii) the duration of phototherapy, (iii) the percentage daily decline rate and (iv) the overall percentage decline rate (p < 0.05). There were no failures of phototherapy and the need for re-exposure was low (4.7% of the total sample), with no difference between groups. The fibreoptic approach represents a promising way to aggregate synergically the most recent optical technologies and develop a modern, efficient and caring phototherapy system for low-birthweight infants.

Fiber Optic Technology↗

PubMed1983

Enteral administration of agar as an effective adjunct to phototherapy of neonatal hyperbilirubinemia.

Phototherapy increases the biliary excretion of unconjugated bilirubin. In this form, bilirubin would be subject to enterohepatic circulation, and the true efficacy of phototherapy would be blunted. We tested the hypothesis that sequestration of lumenal unconjugated bilirubin by enteral agar administration would enhance the efficacy of phototherapy in jaundiced infants. Fifty-two infants were studied, 21 control and 31 agar-supplemented. The birth weights, sex distribution, and postnatal age at onset of phototherapy did not differ between the two groups of infants; pre- and post-phototherapy bilirubin concentrations also did not differ between the groups. The bile acid concentrations and bilirubin saturation indices were also similar. The rate of declination of the plasma bilirubin concentrations after 24 h of phototherapy was greater and significantly more uniform in the agar-supplemented infants (-1.59 +/- 2.3 versus -2.51 +/- 1.44). Stool frequencies were greater in control infants (5.5 versus 4.3 per 24 h) whereas fecal bilirubin excretions were greater in agar-supplemented infants during the second day of phototherapy (1.32 versus 3.29 mg . kg-1 . 24 h-1). Agar supplementation reduced the duration of phototherapy by 23% (37.6 +/- 3.2 versus 48.1 +/- 5.0 h).

Agar↗

PubMed2006

Novel kinetic insights into treatment of unconjugated hyperbilirubinemia: phototherapy and orlistat treatment in Gunn rats.

Treatment with phototherapy or with the lipase inhibitor orlistat decreases plasma unconjugated bilirubin (UCB) concentrations in hyperbilirubinemic Gunn rats. We investigated the mechanism(s) underlying the effects of orlistat, phototherapy, and combined treatment, using steady-state 3H-UCB kinetics. After three weeks of treatment with orlistat (200 mg/kg chow), phototherapy (19 microW/cm2/nm) or combined treatment, tracer 3H-UCB was administered IV to treated and untreated (control) Gunn rats. Plasma samples and feces were collected every 12h for 60h, and bile for 30 min at 60h. The following results were obtained: 1) each treatment decreased plasma bilirubin levels compared with controls: orlistat- 19%, phototherapy-32%, combined treatment-53%; 2) plasma bilirubin concentrations were strongly, negatively correlated with fractional bilirubin turnover; 3) orlistat treatment induced net transmucosal excretion of UCB into the intestinal lumen, whereas phototherapy increased biliary UCB excretion rate; 4) all treatments profoundly increased the enterohepatic circulation of UCB derivatives, indicating enhanced metabolism by intestinal bacteria. In conclusion, orlistat and phototherapy lower plasma bilirubin concentrations in Gunn rats by increasing (net) intestinal influx of UCB, either by transmucosal excretion (orlistat), or increased biliary secretion (phototherapy). The mechanism of phototherapy and orlistat treatment involves increasing the availability of UCB in the intestinal lumen for fecal excretion and for metabolism by intestinal bacteria.

Animals↗

PubMed2004

Impact of phototherapy on vasoactive mediators: NO and VEGF in the newborn.

AIM: The objective of this study was to evaluate the effects of close and remote phototherapy on serum nitric oxide (NO) and vascular endothelial growth factor (VEGF) levels as well as on body temperature heart rate and blood pressure in neonates of different gestational ages. PATIENTS AND METHOD: Term (gestational age > or = 37 weeks) and preterm neonates (GA < 37 weeks) with hyperbilirubinemia requiring phototherapy were included in the study. All patients except for the ones in incubators were randomized to receive either close phototherapy (15 cm above the patient) or remote phototherapy (30-45 cm above patient). Body temperature, heart rate and blood pressure were measured before treatment, six hours into treatment and one hour after cessation of treatment. Blood samples for NO and VEGF measurements were also taken at the same times. RESULTS: Sixty-one term newborns and 37 preterm newborns were included in the study. Patients were distributed into four groups according to the dose of treatment together with gestational age, i.e. term close and remote photoherapy groups (n = 29, n = 32, respectively), preterm close and remote photoherapy groups (n=10, n=27, respectively). Body temperature increased significantly with phototherapy in all groups but was not at hyperthermia level. Heart rate increased in all groups except for term newborns in the remote phototherapy group and blood pressure decreased in term infants but was unchanged in preterms. None of these changes were at the level of tachycardia or hypotension for a newborn. Phototherapy did not result in elevation of NO or VEGF levels. CONCLUSION: This study showed that in our group of patients close or remote phototherapy caused some body temperature, heart rate and blood pressure changes that were not clinically significant and did not result in increased levels of NO or VEGF, which are well known vasodilator mediators.

Blood Pressure↗

PubMed2001

Transepidermal water loss during conventional phototherapy in nonhemolytic hyperbilirubinemia term infants.

The evaporation rate from the skin was measured in 40 healthy term infants and 40 non-hemolytic jaundice term infants who required phototherapy. All infants were born at the gestational age of 38-41 weeks. The method for measurement of evaporation rate was based on determination of the water pressure gradient close to the skin surface. Conventional phototherapy was given in open cribs. In the phototherapy group, non of the infants had received phototherapy before the start of measurement. Evaporation rate was measured at the chest, interscapular and buttock. The measurement was made before phototherapy, 30 minutes, and 6 hours after starting phototherapy. The mean evaporation rate increased from 7.2 to 7.8 and 8.4 g/m2 h, respectively (p<0.001). In the control group, the measurement was made at the consecutive time as in the phototherapy group. The mean of the evaporate rate was 7.3, 7.6 and 7.5 g/m2 h (p=0.30). We conclude that conventional phototherapy in full term infants in open cribs increases transepidermal water loss.

Analysis of Variance↗

PubMed2004

[Prescription of phototherapy in psoriasis].

Two types of phototherapy are used in the treatment of psoriasis. UVB phototherapy (so called TL01 excluding the most erythematogenic UVB) has acquired a position next to puvatherapy (associating co-administration of a psoralen either by oral intake or bath, with exposure to UVA) of which the efficacy has been clearly established for a long time. The use of UVB TL01 phototherapy presents less constraint but doesn't seem to be as efficient as puvatherapy in the more severe forms. The results of these two phototherapies are amplified by the addition of adjuvant treatments, in particular with the association of the oral intake of acitretin. The long-term risk of phototherapy is the induction of cutaneous cancers, essentially spinocellular carcinomas; this risk, qualified and quantified for puva, remains less clear for TL01; it imposes the need for a precise count of the number of sessions received and a prolonged follow-up of patients having received numerous phototherapy treatments. The indication for phototherapy is an extensive flare-up of psoriasis in its common form. Therapeutic rotation, during successions of flare-ups or when the phototherapy capital has been consumed, can be done with a retinoid or methotrexate, conversely it has to be much more careful with cyclosporin due to the increase of the carcinogenic risk.

Acute Disease↗

PubMed2005

[Intranasal phototherapy for the treatment of allergic rhinitis].

INTRODUCTION: Allergic rhinitis is a frequent disease, accompanied by significant social-economic costs and a negative impact on the quality of life. Phototherapy has a profound immunosuppressive effect and is effectively used in the treatment of several immune mediated skin diseases such as atopic dermatitis. AIMS: The authors investigated the efficacy of intranasal phototherapy with a combination of low doses of ultraviolet-B, ultraviolet-A and visible light in allergic rhinitis. METHODS: A randomized, double-blind, placebo-controlled study was conducted in patients with a history of at least 2 years of moderate to severe ragweed-induced allergic rhinitis that was not controlled by anti-allergic drugs. Intranasal phototherapy was performed 3 times a week for 3 weeks. As placebo low intensity visible light was used. RESULTS: Phototherapy resulted in a significant improvement of clinical symptoms for nasal itching, rhinorrhea, sneezing and total nasal score. Scores for nasal obstruction slightly improved during phototherapy while a significant increased was found in the placebo group. In the overall efficacy assessment, both patients and investigators found phototherapy significantly more efficient than placebo. Phototherapy was well tolerated, the only side effect was the slight dryness of the nasal mucosa. CONCLUSIONS: These results suggest that intranasal phototherapy is effective for the treatment of allergic rhinitis, and opens up new opportunities for the treatment of immune-mediated mucosal diseases.

Adult↗

PubMed2006

Effect of phototherapy on cardiorespiratory activity during sleep in neonates with physiologic jaundice.

BACKGROUND: Phototherapy is considered the standard of care for neonatal jaundice. However, its short-term cardiorespiratory effects have not been studied thoroughly. OBJECTIVES: To assess the cardiorespiratory effect of phototherapy during sleep in term infants with physiologicjaundice. METHODS: We performed two polysomnography studies during 3 hours sleep in 10 healthy term infants with physiologic jaundice; each infant served as his/her own control. The first study was performed just prior to phototherapy and the second study during phototherapy 24 hours later. Heart and respiratory rates, type and duration of apneas, and arterial oxygen saturation were analyzed during active and quiet sleep. RESULTS: Term infants (gestational age 38.6 +/- 1.4 weeks, birth weight 3.2 +/- 0.5 kg) underwent the two polysomnography studies within a short time interval and had a comparable bilrubin level (3.6 +/- 0.8 and 4.5 +/- 0.8 days; 14.5 +/- 1.4 and 13.8 +/- 2.1 mg/dl, P = NS, respectively). There was no difference in sleeping time or the fraction of active and quiet sleep before or during phototherapy. During active sleep under phototherapy there was a significant decrease in respiratory rate and increase in heart rate (54.3 +/- 10.3 vs. 49.1 +/- 10.8 breaths/minute, and 125.9 +/- 11.7 vs. 129.7 +/- 15.3 beats/minute, respectively, P < 0.05), as well as a decrease in respiratory effort in response to apnea. These effects were not found during quiet sleep. Phototherapy had no significant effect on oxygen saturation, apnea rate or periodic breathing in either sleep state. No clinical significant apnea or bradycardia occurred. CONCLUSIONS: Phototherapy affected the cardiorespiratory activity during active sleep but not during quiet sleep in term infants with physiologic jaundice. These effects do not seem to have clinical significance in "real-life" conditions.

Heart Rate↗

PubMed2004

Association of variants in angiotensin-converting enzyme and endothelin-1 genes with phototherapy in cutaneous T-cell lymphoma.

BACKGROUND: The cutaneous T-cell lymphoma (CTCL) is a disease characterised by cutaneous infiltrates of malignant, clonally expanded T-cells. Because individual genetic determination of angiogenetic and antioxidant properties of blood vessels could be partly responsible for phototherapy in CTCL patients, three polymorphisms in angiotensin converting enzyme and endothelin-1 genes were determined. METHODS: 77 patients with CTCL, diagnosed and treated at the First Dermatological Clinic of St. Ann's Faculty Hospital Brno (46 men and 31 women, median age 62, range 26-80 years) were compared to a control non-CTCL group of the similar age and gender distribution (n=203: 137 men and 66 women, median age 54, range 27-86 years) with negative family history of severe skin diseases and without signs of malignancy. Diagnosis of CTCL was verified according to the clinical picture and histologically. The genotype distributions and allelic frequencies between CTCL with phototherapy and those without phototherapy were compared. RESULTS: Significant differences were found in genotype distributions of I/D ACE polymorphism between CTCL patients treated with phototherapy and those treated without it. Heterozygote ID was more frequent in the group treated with phototherapy (25/13 vs. 12/27, OR=4.33, 95% confidential interval 1.67-11.24, P=0.02. The 4A4A variant of -3A/-4A EDN1 is more frequent in patients treated with phototherapy (8/30 vs. 1/38, OR=10.13, 95% confidential interval 1.20-85.55, P=0.01). The GA and AA genotypes of G8002A EDN1 polymorphism are more frequent in CTCL patients treated with phototherapy compared to those without it (15/23 vs. 7/32, OR=2.98, 95% confidential interval 1.05-8.48, P=0.03). DISCUSSION: Some polymorphic variants in ACE and EDN1 genes (a heterozygote ID in I/D ACE, a homozygote -4A-4A in -3A /-4A EDN1 and genotypes GA and GG in G8002A EDN1) seem to carry an advantage for phototherapy effectiveness in patients with CTCL.

Journal Article↗

PubMed1989

Effect of phototherapy on serum 25-hydroxyvitamin D in the Antarctic.

The hypothesis that sunlight may induce the enzymes involved in the vitamin D pathway has been tested by comparing the ability to synthesize vitamin D3 and its 25 hydroxy metabolite (25-OHD) in 2 groups of male volunteers resident at the British Antarctic base at Rothera Point (67 degrees 34'S.). One group endured the UV depleted winter and the other group received regular phototherapy throughout the winter. Both groups then received a course of 14 days phototherapy in October (Southern Hemisphere spring). The group receiving regular phototherapy had a trend towards a higher level of serum 25-OHD, and the October phototherapy course produced a further small increase in serum 25-OHD values. In the previously non irradiated group the October phototherapy produced a much larger increase in serum 25-OHD so that they attained the previously higher values of the pre-iradiated group. There was a negative correlation between the pre October phototherapy serum concentration of 25-OHD and the subsequent increment (r-0.78, p less than 0.01) but no relationship between the serum 25-OHD and D3 after phototherapy. These results provide evidence against the existence of enzyme induction of vitamin D 25 hydroxylase by light.

Adult↗

PubMed1999

Responsiveness of cutaneous vasculature to thermal stimulation during phototherapy in neonatal jaundice.

The present study was performed to measure the vasoregulatory reactions to dynamic changes in local skin temperature during open bed phototherapy. Periodic thermal stimulation using warm and cool air currents was applied to the skin of ten term infants with physiological jaundice, before and during open bed phototherapy. The reactivity of skin blood flow (SBF) and heart rate was measured using laser Doppler flowmetry and power spectral analysis. The baseline SBF increased significantly by 70% (P = 0.008) during phototherapy without any significant change in skin or rectal temperature. Before phototherapy, the rhythmic (0.08 Hz) thermal skin stimulation increased the oscillations of SBF (from 89 +/- 26 au to 213 +/- 37 au, P = 0.02) at the stimulation frequency band. This response was further increased (P = 0.03) during phototherapy (from 198 +/- 54 au to 658 +/- 115 au, P = 0.004). Phototherapy increased SBF in icteric otherwise healthy neonates. The cutaneous vasodilatation augments the cardiovascular responsiveness to thermal stimulation. These results suggest that open bed phototherapy does not inhibit the cardiovascular responsiveness to local thermal skin stimulation in healthy term infants.

Heart Rate↗

PubMed1999

Phototherapy for neonatal hyperbilirubinemia affects cytokine production by peripheral blood mononuclear cells.

The capacity of peripheral blood mononuclear cells (PBMC) to produce interleukin (IL) IL-1beta, IL-2, IL-3, IL-6, IL-10 and tumor necrosis factor-alpha (TNFalpha) was examined in term newborns with hyperbilirubinemia after 24 hours' exposure to phototherapy (wave length 425-475 nm). The results were compared with those from untreated neonates. Fifty newborns spontaneously delivered at term were included in the study. Blood samples were collected from 20 newborns before and 24 h after phototherapy. The control group consisted of 30 neonates examined on two consecutive days. PBMC isolated from blood samples were incubated in vitro for cytokine production. The concentration of cytokines in the supernatants was tested using ELISA kits (for IL-1beta, IL-6, IL-10 and TNFalpha), or by bioassays (for IL-2 and IL-3). Phototherapy caused a 70% increase in IL-2 secretion (123 +/- 27 vs 208 +/- 30 units/ml, P < 0.01) and 56% in IL-10 production (1.07 +/- 0.19 vs 1.67 +/- 0.33 ng/ml, P < 0. 03), whereas the spontaneous secretion of IL-1beta was reduced by 43% (13.7 +/- 2.3 vs 7.3 +/- 1.7 ng/ml, P < 0.02). In the control group the secretion of these cytokines was similar on the two consecutive days and did not differ significantly from secretion in the other group before phototherapy. On the other hand, lipopolysaccharide induced TNFalpha production was higher on the second day in the two groups of newborns irrespective of phototherapy (388 +/- 58 vs 683 +/- 88 pg/ml, P < 0.001, in the control group and 384 +/- 75 vs 588 +/- 91, P < 0.05, before and after phototherapy). The synthesis of IL-3 and IL-6 did not change significantly between the two days of the study. The results demonstrate that in addition to the well-known positive effect of phototherapy on the neonate serum bilirubin level, this treatment affects the function of the immune system in newborns via alterations in cytokine production.

Cytokines↗

PubMed1974

Effect of phototherapy in preterm infants on growth in the neonatal period.

A total of 120 preterm infants were randomly divided at 24 hr of age into three groups: Group I, controls; Group II, continuous phototherapy for 5 days; and Group III, intermittent phototherapy (12 hr on and 12 hr off) for 5 days. At the end of week 1 80% of the control group regained and surpassed their birth weight as opposed to 44 and 57.6% in the continuous and intermittent phototherapy groups, respectively. In weeks 2 and 3 both phototherapy groups had greater weight gain than the control group. Similar but less marked differences were observed in body lenth and head circumference in the three groups. Data suggest decreased growth during phototherapy with subsequent catch-up in growth during weeks 2 and 3. Differences were less marked between infants on intermittent (rather than continuous) phototherapy and controls. Increased metabolic demands and decreased intestinal absorption during phototherapy may be two of the factors responsible for the observed differences in growth in the three groups.

Body Height↗

PubMed1995

Oxidation of parenteral lipid emulsion by ambient and phototherapy lights: potential toxicity of routine parenteral feeding.

Vitamin E can be a prooxidant in isolated lipoprotein suspensions. Because lipid emulsions used in parenteral nutrition are lipoprotein-like suspensions rich in polyunsaturated fatty acids and vitamin E, we hypothesized that vitamin E may act as a prooxidant in lipid emulsions, as it is in lipoprotein suspensions. We therefore exposed an intravenously administered lipid emulsion (Intralipid) to a single spotlight commonly used in the treatment of neonatal jaundice, and measured the formation of triglyceride hydroperoxides by using high-performance liquid chromatography with postcolumn chemiluminescence detection. Concentrations of these hydroperoxides in different batches of fresh intralipid were usually approximately 10 mumol/L but increased up to 60 times after exposure to phototherapy light for a period of 24 hours, even though significant amounts of vitamin E were present at the end of the exposure. Triglyceride hydroperoxides were formed during phototherapy light exposure whether the intralipid was in plastic tubing used routinely for infusion or in glass containers. Ambient light also caused significant peroxidation of the formula lipids, although to a much lesser extent than observed with phototherapy light. For infants in the neonatal intensive care unit who were receiving intralipid but not phototherapy, solutions being infused at the end of 24 hours contained a mean of 40 mumol/L hydroperoxides. For infants receiving phototherapy, the mean was 97 mumol/L. Phototherapy light-induced formation of triglyceride hydroperoxides was prevented by covering the intralipid with aluminum foil or supplementation with sodium ascorbate before light exposure. We conclude that intralipid is highly susceptible to oxidation and that elevated levels of oxidized lipids can be formed during its clinical use, especially when intralipid infusion is combined with phototherapy. Because lipid hydroperoxides are cytotoxic and can cause adverse effects, inadvertent infusion of rancid intralipid may add to the numerous problems encountered by premature neonates.

Aluminum↗

PubMedDate not supplied

Phototherapy in pediatric patients.

The treatment of children with psoriasis, atopic dermatitis (AD), pityriasis lichenoides, and scleroderma poses a therapeutic problem because all therapeutic options are associated with numerous side effects. Therefore ultraviolet A and B (UVA and UVB) phototherapy is presented as a possible alternative to some of these therapies, primarily topical and systemic corticosteroids, in children. Our results in treating children with phototherapy and psoralen plus UVA (PUVA) bath phototherapy over the past 5 years are reported. UVB therapy (TL01) was used in 20 psoriatic children (6 boys, 14 girls; ages 6-14 years) during the stage of disease exacerbation and in 9 children (3 boys, 6 girls; ages 8-16 years) with pityriasis lichenoides. Combined UVA/UVB phototherapy was applied in 21 AD children (7 boys, 14 girls; ages 4-15 years). Photochemotherapy with local application of a PUVA bath was used in six children (2 boys, 4 girls; ages 9-16 years) with circumscribed scleroderma and in one girl with systemic scleroderma. All children received short courses of phototherapy with either no maintenance or short maintenance. All three therapeutic protocols resulted in a certain degree of improvement in most of the study patients. None of the patients exhibited any early phototherapy side effects. We conclude that phototherapy and PUVA bath are valuable and safe therapeutic options for selected children who do not respond to other treatments.

Adolescent↗

PubMed1999

Cardiac output and ductal reopening during phototherapy in preterm infants.

Left ventricular output (LVO), left pulmonary artery blood flow (LPA) and patency of the ductus arteriosus (PDA) were studied with 2D/pulsed Doppler ultrasound before, during and after phototherapy treatment in 27 preterm infants (gestational age < or =32 wk), who were exposed for a minimum of 12 h to phototherapy for non-haemolytic hyperbilirubinemia. In 14 infants (52%) the ductus arteriosus reopened during phototherapy, but ductal patency was not of haemodynamic importance. LVO initially decreased in preterm infants in whom the ductus did not reopen. From 12 h until discontinuation of phototherapy, LVO and LPA were higher than before phototherapy in all infants. After withdrawal of phototherapy, LVO and LPA returned to pre-phototherapy values.

Analysis of Variance↗

PubMed1986

Metabolism of bilirubin and its photoisomers in newborn infants during phototherapy.

Bilirubin and its photoisomers in the biological fluids of a hyperbilirubinaemic newborn infant before and during phototherapy were analyzed by a recently improved HPLC method. In the serum, the percentages of (EZ)- and (ZE)-bilirubin in the total bilirubin concentration before phototherapy were approximately 10% and on average increased over 1.5-fold at 2 h after initiation of phototherapy. The percentage of the (EZ)-cyclobilirubin in the serum bilirubin was under 1%. In the bile, the mean concentration of (ZZ)-bilirubin, derived mainly from (ZE)-bilirubin, nearly tripled during phototherapy. The (EZ)-cyclobilirubin concentration in the bile was very low before phototherapy, increased nearly ten-fold at 3 h after initiation of phototherapy, and was 5- to 6-fold as high as that of (ZZ)-bilirubin. In the urine, upon exposure to light, the urinary concentration of (EZ)-cyclobilirubin is apparently equivalent to half of the biliary concentration of (ZZ)-bilirubin and one-fifth of that of (EZ)-cyclobilirubin. It was concluded that during phototherapy of neonatal hyperbilirubinaemia the structural photoisomer [(EZ)-cyclobilirubin] predominates considerably over the geometric photoisomer [(ZE)-bilirubin].

Bilirubin↗