Transforaminal Epidural Block and Erector Spinae Plane Block to Manage Acute Zoster-Associated Pain: A Retrospective Case-Control Study.

Background and Objectives: Achieving adequate pain reduction in the acute phase of herpes zoster is essential for preventing postherpetic neuralgia (PHN). For this purpose, appropriate antiviral medications, oral analgesic medications, and various nerve block methods could be applied. Erector spinae plane block (ESPB) is a simple, novel ultrasound-guided block technique, and its use has increased because the procedure is convenient and relatively safe. Although several cases have reported the zoster-associated pain (ZAP) control effect of ESPB, the efficacy of ESPB has not been compared with that of other types of nerve blocks for managing ZAP. This study aimed to compare the efficacy of ESPB with that of other types of nerve blocks for managing ZAP. Study Design: Retrospective case-control study. Materials and Methods: Medical records of 53 patients with acute thoracic herpes zoster were reviewed. We divided the participants into two groups: patients who received transforaminal epidural injection (TFEI) (n = 32) and those who received ESPB (n = 21). The efficacy of the procedure was assessed by a numerical rating scale (NRS) and by recording patient medication doses before the procedure and at 1 week, 1 month, 2 months, and 3 months after the procedure. Results: The time required for pain intensity to decrease to NRS ≤ 2 was not significantly different between the groups. The rate of medication discontinuation also was not different between the groups. There was no significant difference between the two groups in the proportion of clinically significant PHN (NRS ≥ 3) at any time point. Limitations: The relatively small sample size from a single center and the retrospective nature of the study served as limitations. Conclusions: The clinical effects of ESPB and TFEI were similar in patients with acute thoracic herpes zoster. ESPB could be considered an interventional option for ZAP management.

Hereditary Leiomyomatosis and Renal Cell Cancer: A Case Report of Pilar Leiomyomatosis with History of Kidney Cancer and Review of the Literature.

Pilar leiomyoma or piloleiomyoma is a benign neoplasm of the smooth muscle arising from the arrector pili muscle. It manifests as brown to red firm papulonodules with sites of predilection being the face, trunk, and extensor surfaces of the extremities. Histologically, the lesions exhibit ill-defined dermal tumors with interlacing fascicles of spindle cells. Some genodermatoses are characterized by the development of visceral tumors and cutaneous leiomyomatosis such as Reed's syndrome, and hereditary leiomyomatosis and renal cell cancer (HLRCC). A 55-year-old male presented with reddish-brown papules and nodules on the face and upper back, accompanied by sharp episodic pain on the face. He had undergone nephrectomy for renal cancer 9 years ago, and his younger brother had similar cutaneous manifestation. Histopathologic findings were consistent with pilar leiomyoma, showing bundles of smooth muscle tumors in the dermis. Based on the clinical information including clinical features, past medical history, and family history, HLRCC was highly suspected. To confirm the diagnosis, whole exome sequencing was performed using peripheral blood, which revealed a novel point mutation (c.739G>A, p.Glu247Lys) in the fumarate hydratase (FH) gene. We describe a confirmed case of HLRCC, which is a genetic disorder with a potential to cause visceral cancers, which dermatologists might overlook as a benign condition.

A Case Report of Rubinstein-Taybi Syndrome Presenting with Extensive Keloid Formation and Review of Literature.

Rubinstein-Taybi syndrome (RSTS) is an extremely rare genetic disorder affecting multi-organ systems. A tendency to form keloid is one of the common dermatologic manifestations. We describe a 23-year-old female presented with extensive keloids which developed spontaneously. She had typical facial features, broad thumbs, and dental defects, which were suspicious features of genetic syndrome. Direct sequencing for cyclic-AMP-regulated enhancer binding protein revealed a novel mutation. So far, 23 cases of RSTS have been reported in Korean literature. To the best of our knowledge, this is the first report in Korea to describe confirmed case of RSTS with extensive keloids as a chief manifestation.

Needleless laser injector versus needle injection for skin enhancement and rejuvenation effect of dermal filler.

BACKGROUND AND OBJECTIVES: A needleless laser-induced microjet injector is a novel transdermal drug delivery system that can rapidly inject a very small and precise drug dose into the skin with minimal pain and downtime. In this study, we aimed to compare the laser-induced microjet injection versus needle injection of polylactic acid/hyaluronic acid filler for skin enhancement and rejuvenation. PATIENTS AND METHODS: A 24-week prospective, single-center, assessor-blinded, randomized, split-face study was conducted. The enrolled patients underwent one treatment session of dermal filler injection using a laser-induced microjet injector on one half of the face or a traditional needle injection on the other half of the face. Evaluation was conducted at baseline before treatment and at 4, 12, and 24 weeks after treatment. RESULTS: A single treatment of filler injection with a laser-induced microjet injector resulted in similar improvements in skin hydration and elasticity as a single treatment of filler injection by using manual needle injection, with reduced pain, side effects, and decreased treatment time. CONCLUSIONS: Laser-induced microjet injector enabled not only the application of a controlled dose and filler depth but also even distribution, improved clinical efficacy, reduced pain and side effects, and sufficient time for clinicians to perform treatment.

Chronic cryptococcal meningitis with a cryptococcoma presenting as normal pressure hydrocephalus: a case report.

Chronic meningitis may present with clinical features related to hydrocephalus. We report a 76-year-old female who presented to an outpatient clinic with cognitive decline and gait disturbance with recurrent falls. The initial diagnosis of normal pressure hydrocephalus (NPH) was based on the clinical symptoms and magnetic resonance imaging (MRI) of the brain, which showed ventriculomegaly without an obstructive lesion. During follow-up, however, there was remarkable cognitive decline, and she was unable to walk without assistance. Lumbar puncture and brain MRI showed respective lymphocyte-dominant pleocytosis that was positive for cryptococcal antigen and a new encapsulated abscess-like lesion in a left caudate head. Treatment for cryptococcal meningitis was initiated, and the patient was cured after a long treatment with an antifungal agent. As chronic meningitis could be misdiagnosed as NPH, differential diagnoses of etiologies that can cause hydrocephalus should be addressed.

Comparison of Acceptance and Commitment Therapy (ACT) and Cognitive Behavior Therapy (CBT) for Chronic Insomnia: A Pilot Randomized Controlled Trial.

Purpose: Acceptance and Commitment Therapy (ACT) is part of the third wave of cognitive behavior therapy, and has six core components: acceptance, cognitive defusion, self as context, being present, values, and committed behavior. This study aimed to examine the efficacy of ACT for insomnia compared with cognitive behavior therapy for insomnia (CBT-I) in patients with chronic primary insomnia. Methods: The study recruited patients with chronic primary insomnia from a university hospital between August 2020 and July 2021. Thirty patients were enrolled and randomly assigned to receive either ACT (n = 15) or CBT-I (n = 15). Interventions were performed over four weeks, with four sessions of face-to-face therapy and four sessions of online therapy. The outcomes were measured using a sleep diary and a questionnaire. Results: Post-intervention, the ACT and CBT-I groups had significantly improved sleep quality, insomnia severity, depression, beliefs about sleep, sleep onset latency (SOL), and sleep efficacy (SE) (p < 0.05). However, anxiety was significantly reduced in the ACT group (p = 0.015), but not in the CBT-I group. Conclusion: ACT had a significant effect on primary insomnia and secondary symptoms, especially anxiety related to insomnia. These findings suggest that ACT could be a potential intervention for individuals who do not respond to CBT-I, who have high anxiety regarding sleep problems.

Neuroprotective effects of melatonin in neurodegenerative and autoimmune central nervous system diseases.

The suprachiasmatic nucleus (SCN) in the anterior hypothalamus is the major circadian pacemaker in humans. Melatonin is a key hormone secreted by the pineal gland in response to darkness. Light-induced stimuli are transmitted along the retinohypothalamic tract to the SCN. Activation of the SCN inhibits the production of melatonin by the pineal gland through a complex neural pathway passing through the superior cervical ganglion. Accordingly, when light is unavailable, the pineal gland secretes melatonin. The circadian rhythm modulates sleep-wake cycles as well as many physiological functions of the endocrine system, including core body temperature, pulse rate, oxygen consumption, hormone levels, metabolism, and gastrointestinal function. In neurodegenerative disorders, the sleep-wake cycle is disrupted and circadian regulation is altered, which accelerates disease progression, further disrupting circadian regulation and setting up a vicious cycle. Melatonin plays a critical role in the regulation of circadian rhythms and is a multifunctional pleiotropic agent with broad neuroprotective effects in neurodegenerative disorders, viral or autoimmune diseases, and cancer. In this review, I discuss the neuroprotective functions of melatonin in circadian regulation and its roles in promoting anti-inflammatory activity, enhancing immune system functions, and preventing alterations in glucose metabolism and mitochondrial dysfunction in neurodegenerative disorders and autoimmune central nervous system diseases.

Quantitative measurement of motor activity during sleep in isolated REM sleep behavior disorder patients using actigraphy before and after treatment with clonazepam.

STUDY OBJECTIVES: We conducted a prospective study to quantify motor activity during sleep measured by actigraphy before and after 3 months of treatment with clonazepam in patients with video-polysomnography (vPSG) confirmed isolated rapid eye movement (REM) sleep behavior disorder (iRBD). METHODS: The motor activity amount (MAA) and the motor activity block (MAB) during sleep were obtained from actigraphy. Then, we compared quantitative actigraphic measures with the results of the REM sleep behavior disorder questionnaire for the previous 3-month period (RBDQ-3M) and of the Clinical Global Impression-Improvement scale (CGI-I), and analyzed correlations between baseline vPSG measures and actigraphic measures. RESULTS: Twenty-three iRBD patients were included in the study. After medication treatment, large activity MAA dropped in 39% of patients, and the number of MABs decreased in 30% of patients when applying 50% reduction criteria. 52% of patients showed more than 50% improvement in either one. On the other hand, 43% of patients answered "much or very much improved" on the CGI-I, and RBDQ-3M was reduced by more than half in 35% of patients. However, there was no significant association between the subjective and objective measures. Phasic submental muscle activity during REM sleep was highly correlated with small activity MAA (Spearman's rho = 0.78, p < .001) while proximal and axial movements during REM sleep correlated with large activity MAA (rho = 0.47, p = .030 for proximal movements, rho = 0.47, p = .032 for axial movements). CONCLUSIONS: Our findings imply that quantifying motor activity during sleep using actigraphy can objectively assess therapeutic response in drug trials in patients with iRBD.

Change of iron content in brain regions after intravenous iron therapy in restless legs syndrome: quantitative susceptibility mapping study.

STUDY OBJECTIVES: The pathomechanism of restless legs syndrome (RLS) is related to brain iron deficiency and iron therapy is effective for RLS; however, the effect of iron therapy on human brain iron state has never been studied with magnetic resonance imaging. This study aimed to investigate the change of brain iron concentrations in patients with RLS after intravenous iron therapy using quantitative susceptibility mapping (QSM). METHODS: We enrolled 31 RLS patients and 20 healthy controls. All participants underwent initial baseline (t0) assessment using brain magnetic resonance imaging, serum iron status, and sleep questionnaires including international RLS Study Group rating scale (IRLS). RLS patients underwent follow-up tests at 6 and 24 weeks (t1 and t2) after receiving 1000 mg ferric carboxymaltose. Iron content of region-of-interest on QSM images was measured for 13 neural substrates using the fixed-shaped method. RESULTS: RLS symptoms evaluated using IRLS were significantly improved after iron treatment (t0: 29.7 ± 6.5, t1: 19.5 ± 8.5, t2: 21.3 ± 10.1; p < .001). There was no significant difference in susceptibility values between the controls and RLS patients at t0. In the caudate nucleus, putamen, and pulvinar thalamus of RLS patients, the QSM values differed significantly for three timepoints (p = .035, .048, and .032, respectively). The post-hoc analysis revealed that the QSM values increased at t1 in the caudate nucleus (66.8 ± 18.0 vs 76.4 ± 16.6, p = .037) and decreased from t1 to t2 in the putamen (69.4 ± 16.3 vs 62.5 ± 13.6, p = .025). Changes in the QSM values for the pulvinar and caudate nuclei at t1 were positively and negatively correlated with symptomatic improvement, respectively (r = 0.361 and -0.466, respectively). CONCLUSIONS: Intravenous iron treatment results in changes in brain iron content which correlate to reductions in RLS severity. This suggests a connection between symptom improvement and the associated specific brain regions constituting the sensorimotor network.

Improving mental health and daytime function in adult insomnia patients predict cognitive behavioral therapy for insomnia effectiveness: A case-control study.

Objective: This study investigated demographic, sleep related symptoms and mental health status as predictors of clinically significant treatment responses to cognitive behavioral therapy in adults who have good adherence for the cognitive behavioral therapy for insomnia (CBT-I) program in primary insomnia. Methods: A total of 42 adults with primary insomnia disorder were treated with CBT-I at a university hospital from June 2020 to January 2021. Demographic variables were surveyed and sleep-related symptoms were measured using self-reported questionnaires before and after the intervention, comprising a 6-week interval. The treatment responder group was defined as patients with an Insomnia Severity Index change score >7 compared to baseline. Logistic regression and paired t-test examined whether these factors predicted treatment outcomes for CBT-I. Results: Demographic variables did not predict treatment outcomes. Higher levels of anxiety were associated with a higher likelihood of treatment response (odds ratio [OR] = 1.234; confidence interval [CI]: 1.008-1.511). More severe insomnia at baseline was associated with a greater likelihood of treatment response (OR = 1.450; CI: 1.121-1.875). The lesser the dysfunctional beliefs and attitudes about sleep, the more effective the treatment response (OR = 0.943; CI: 0.904-0.984). Unlike the group of treatment responders, daytime function, depressive mood, and anxiety status did not improve in the group of treatment non-responders after CBT-I intervention. Conclusions: Patients with severe insomnia and anxiety at baseline should be treated more aggressively with CBT-I. During treatment, patients' mental health problems and daytime activities should be continuously monitored, in order to help improve these problems which might strengthen the effectiveness of CBT-I.

A Randomized Split-Face Study of Photodynamic Therapy With St. John's Wort and Indole-3-Acetic Acid for the Treatment of Acne.

BACKGROUND: St. John's wort (SJW) contains hypericin, a powerful photosensitizer with antimicrobial and anti-inflammatory activities. OBJECTIVE: To compare the efficacy and safety of SJW-photodynamic therapy (PDT) with that of indole-3-acetic acid (IAA)-PDT for the treatment of acne and investigate the skin rejuvenating effects of SJW-PDT. MATERIALS AND METHODS: In vitro experiments were conducted to examine the generation of reactive oxygen species and the antimicrobial effects of SJW-PDT. In the prospective, double-blind, split-face, randomized study, 31 patients with facial acne were treated with SJW or IAA with simultaneous illumination of red light and green light. RESULTS: SJW produces free radicals with visible light irradiation, and the growth of Cutibacterium acnes and Staphylococcus aureus is significantly suppressed. One week after the last treatment, the acne lesion counts were significantly decreased in both groups (56.5% reduction in SJW, p < .001 vs 57.0% in IAA, p < .001). Significant reductions in sebum secretion, erythema index, roughness, and wrinkles were observed in both groups after the treatment. No side effects were observed. CONCLUSION: SJW-PDT is a simple, safe, and effective treatment option for acne that is also beneficial for skin rejuvenation.

Efficacy and Safety of the Micro-insulated Needle Radiofrequency Device for Reduction of Submental Fat.

BACKGROUND: Recently, it has been reported that a micro-insulated needle radiofrequency (RF) system is effective at achieving subcutaneous fat reduction; however, no study has yet applied this technique to reduce submental fat. OBJECTIVE: To evaluate the efficacy and safety of a fractional RF device with a micro-insulated needle to reduce submental fat. MATERIALS AND METHODS: In this prospective, single-blinded, pre-post comparative study, 24 adults with excess submental fat were treated once using a micro-insulated needle RF device. Outcomes included efficacy (submental fat rating by an independent investigator, fat volume quantified with a 3-dimensional camera, and patient satisfaction), assessed 1 and 2 months after the procedure, and safety (adverse events), assessed throughout the study. RESULTS: The patients' Physician-Assisted Submental Fat Rating Scale score significantly decreased after 1 month and further decreased after 2 months. The average volume of submental fat was significantly decreased after 2 months (20.44 ± 5.53 cc to 16.41 ± 4.58 cc, p < .001). Patient satisfaction was high. Transient and mild local skin reactions without long-term sequelae were observed in 4 patients. CONCLUSION: The micro-insulated needle RF device is beneficial for the reduction of submental fat and has tolerable safety profiles. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT05517824.

Development of a new classification and scoring system for scalp conditions: Scalp Photographic Index (SPI).

BACKGROUND AND OBJECTIVES: There has been no validated tool for objectively quantifying the overall condition and characteristics of the scalp. This study aimed to establish and validate a new classification and scoring system for evaluating scalp conditions. METHODS: The Scalp Photographic Index (SPI) using a trichoscope grades five features of scalp conditions (dryness, oiliness, erythema, folliculitis, and dandruff) on a score of 0-3. To evaluate the validity of SPI, SPI grading was performed by three experts on the scalps of 100 subjects along with a dermatologist's assessment of the scalps and a scalp-related symptom survey. For reliability assessment, 20 healthcare providers performed SPI grading for the 95 selected photographs of the scalp. RESULTS: SPI grading and the dermatologist's scalp assessment showed good correlations for all five scalp features. Warmth showed a significant correlation with all features of SPI and the subjects' perception of a scalp pimple had a significant positive correlation with the folliculitis feature. SPI grading demonstrated good reliability with excellent internal consistency (Cronbach's α = 0.90) and strong inter- and intra-rater reliability (Kendall's W = 0.84, ICC(3,1)=0.94). CONCLUSIONS: SPI is an objective, reproducible, and validated numeric system for classifying and scoring scalp conditions.

Topical methylene blue nanoformulation for the photodynamic therapy of acne vulgaris.

Acne vulgaris is a common skin disease caused by multifactorial reasons involving excessive sebum secretion and inflammation by Cutibacterium acnes (C. acnes). Various conventional therapies are available for the treatment of acne vulgaris; however, topical photodynamic therapy (PDT) has attracted much attention because of its great potential for sebum-reducing, anti-inflammatory, and antimicrobial activities. Although 5-aminolevulinic acid (ALA) has been broadly used as a photosensitizer for topical PDT, it has several limitations such as long incubation time, pain, and post-inflammatory hyperpigmentation. Here, we report a biocompatible nanoformulation consisting of methylene blue and salicylic acid (MBSD), as a potent PDT and acne therapeutics, enclosed within oleic acid. Photoactivated MBSD showed antimicrobial activity against C. acnes along with long-term stability. When 24 patients with acne were treated with MBSD and light irradiation 5 times at 1-week intervals, MBSD-based PDT exhibited a remarkable reduction in acne lesions and sebum production. In addition, the therapeutic procedure was painless and safe, without any adverse events. Therefore, MBSD is a promising topical PDT agent for biocompatible, safe, and effective acne treatment.

Early Postoperative Injections of Polydeoxyribonucleotide Prevent Hypertrophic Scarring After Thyroidectomy: A Randomized Controlled Trial.

Objective: Polydeoxyribonucleotide (PDRN) is known to enhance wound healing, but there has been no clinical trial investigating the effect of PDRN on scar prevention in surgical wounds. This study aimed to evaluate the efficacy of PDRN administration in preventing postoperative scars. Approach: In this randomized controlled trial (NCT05149118), 44 patients who underwent open thyroidectomy were randomly assigned to the PDRN treatment or untreated control group. Only patients in the treatment group received two consecutive injections of PDRN 1 and 2 days after surgery. The modified Vancouver Scar Scale (mVSS), patients' subjective symptoms, erythema index (EI), melanin index (MI), and scar height were assessed 3 months after surgery. Results: Patients in the treatment group had lower mVSS scores (1.619 ± 1.244 vs. 2.500 ± 1.540, respectively; p = 0.059) and a significantly lower vascularity subscore (0.476 ± 0.512 vs. 0.900 ± 0.447, respectively; p = 0.010) than those in the control group at the 3-month follow-up. Compared with the control group, the level of subjective symptoms, EI, and scar height were all significantly lowered in the PDRN injection group. No specific side effects related to PDRN injection were observed. Innovation: This is the first clinical study that demonstrated that PDRN injections rapidly decreased postsurgical wound erythema and as a result, significantly reduced both excessive scar formation and accompanying symptoms. Conclusion: Early postoperative injection of PDRN is an effective and safe treatment to prevent hypertrophic scars and improve scar outcomes.

Grabody B, an IGF1 receptor-based shuttle, mediates efficient delivery of biologics across the blood-brain barrier.

Effective delivery of therapeutics to the brain is challenging. Molecular shuttles use receptors expressed on brain endothelial cells to deliver therapeutics. Antibodies targeting transferrin receptor (TfR) have been widely developed as molecular shuttles. However, the TfR-based approach raises concerns about safety and developmental burden. Here, we report insulin-like growth factor 1 receptor (IGF1R) as an ideal target for the molecular shuttle. We also describe Grabody B, an antibody against IGF1R, as a molecular shuttle. Grabody B has broad cross-species reactivity and does not interfere with IGF1R-mediated signaling. We demonstrate that administration of Grabody B-fused anti-alpha-synuclein (α-Syn) antibody induces better improvement in neuropathology and behavior in a Parkinson's disease animal model than the therapeutic antibody alone due to its superior serum pharmacokinetics and enhanced brain exposure. The results indicate that IGF1R is an ideal shuttle target and Grabody B is a safe and efficient molecular shuttle.

Emotional and Environmental Factors Aggravating Dream Enactment Behaviors in Patients with Isolated REM Sleep Behavior Disorder.

Objective: To identify emotional and environmental factors that aggravate dream enactment behaviors (DEBs) in isolated rapid eye movement (REM) sleep behavior disorder (iRBD). Methods: In this cross-sectional study, a total of 96 polysomnography-confirmed iRBD patients (mean age, 68.5 years; men, 68%) and their caregivers completed questionnaires regarding potential aggravating factors related to DEBs, including emotion/feelings (stress, anger, anxiety, depressive mood, fatigue, pain), food (alcohol, caffeine, overeating in the evening, fasting/hunger), activities and sleep patterns (strenuous exercise, sex before bed, conflict/fighting, sleep deprivation, oversleeping, sleeping away from home, watching TV before bed), weather/environmental factors (cloudy or rainy weather, heat, cold, noise) and medication (skipping medication, taking hypnotics). Results: The patients reported that stress (61%) was the most aggravating factor for DEBs, followed by anxiety (56%), anger (51%), fatigue (49%), and watching TV before bed (46%). Similarly, the caregivers reported that these factors were most relevant to the aggravation of DEBs in the patients, although some factors were ranked differently. In the subgroup analyses, aggravating factors for DEBs did not differ by RBD symptom severity. Interestingly, the proportion of patients experiencing DEB aggravation by stress, anxiety and depressive mood was significantly higher in women than in men. Furthermore, depressed patients reported that stress and cloudy or rainy weather made DEBs worse than nondepressed patients. Conclusion: Our results suggest that DEBs in iRBD patients may be mainly aggravated by emotional factors. These negative effects appeared to be more prominent in female and depressed patients.

Association of Nucleus Basalis of Meynert Functional Connectivity and Cognition in Idiopathic Rapid-Eye-Movement Sleep Behavior Disorder.

BACKGROUND AND PURPOSE: Cognitive impairments are common in isolated rapid-eye-movement sleep behavior disorder (iRBD), in which the cholinergic system may play an important role. This study aimed to characterize the cortical cholinergic activity using resting-state functional connectivity (FC) of the nucleus basalis of Meynert (NBM) according to the cognitive status of iRBD patients. METHODS: In this cross-sectional study, 33 patients with polysomnography-confirmed iRBD and 20 controls underwent neuropsychological evaluations and resting-state functional magnetic resonance imaging. Thirteen of the iRBD patients had mild cognitive impairment (iRBD-MCI), and the others were age-matched patients with normal cognition (iRBD-NC). The seed-to-voxel NBM-cortical FC was compared among the patients with iRBD-MCI, patients with iRBD-NC, and controls. Correlations between average values of significant clusters and cognitive function scores were calculated in the patients with iRBD. RESULTS: There were group differences in the FC of the NBM with the left lateral occipital cortex and lingual gyrus (adjusted for age, sex, and education level). The strength of FC was lower in the iRBD-MCI group than in the iRBD-NC and control groups (each post-hoc p<0.001). The average NBM-lateral occipital cortex FC was positively correlated with the memory-domain score in iRBD patients. CONCLUSIONS: The results obtained in this study support that cortical cholinergic activity is impaired in iRBD patients with MCI. FC between NBM and posterior regions may play a central role in the cognitive function of these patients.

White matter tract-specific microstructural disruption is associated with depressive symptoms in isolated RBD.

OBJECTIVE: White matter (WM) tract-specific changes may precede gray matter loss in isolated rapid eye movement sleep behavior disorder (iRBD). We aimed to evaluate tract-specific WM changes using tract-specific statistical analysis (TSSA) and their correlation with clinical variables in iRBD patients. METHODS: This was a cross-sectional single-center study of 50 polysomnography-confirmed iRBD patients and 20 age- and sex-matched controls. We used TSSA to identify tract-specific fractional anisotropy (FA) and mean diffusivity (MD) in fourteen major fiber tracts and analyzed between-group differences in these values. Correlations between FA or MD values and clinical variables, including RBD symptom severity, depression and cognition, were evaluated. RESULTS: Patients with iRBD showed lower FA in the right anterior thalamic radiation (ATR) and higher MD in the bilateral ATR and right inferior fronto-occipital fasciculus (IF-OF) than controls after adjusting for age, sex, and years of education. MD values in the IF-OF positively correlated with scores on the Korean version of the Rapid Eye Movement Sleep Behavior Disorder Questionnaire-Hong Kong (RBDQ-KR, p = 0.042) and the Korean version of the geriatric depression scale (GDS-K, p = 0.002) in iRBD patients. Only GDS-K scores independently correlated with IF-OF MD values after adjusting for RBDQ-KR scores (adjusted p = 0.026). CONCLUSION: This study suggests WM microstructural disruption in the bilateral ATR and right IF-OF in patients with iRBD and that alterations in the IF-OF may contribute to depressive symptoms.