Adenotonsillectomy for the Treatment of Obstructive Sleep Apnea in Children with Prader-Willi Syndrome: A Meta-analysis

2019 ◽  
Vol 162 (2) ◽  
pp. 168-176
Author(s):  
Chia-Hsuan Lee ◽  
Wei-Chung Hsu ◽  
Jenq-Yuh Ko ◽  
Te-Huei Yeh ◽  
Ming-Tzer Lin ◽  
...  
Keyword(s):  
Obstructive Sleep Apnea ◽  
Sleep Apnea ◽  
Success Rate ◽  
Cochrane Review ◽  
Velopharyngeal Insufficiency ◽  
Apnea Hypopnea Index ◽  
Prader Willi Syndrome ◽  
Postoperative Changes ◽  
Obstructive Sleep ◽  
Osa Treatment

Objective Adenotonsillectomy outcomes in obstructive sleep apnea (OSA) treatment among children with Prader-Willi syndrome (PWS) remain unclear. This study aimed to elucidate the effectiveness of adenotonsillectomy in OSA treatment among children with PWS. Data Source PubMed, MEDLINE, Embase, and Cochrane Review up to February 2019. Review Methods The registry number of the protocol published on PROSPERO was CRD42015027053. Two authors independently searched the relevant database. Polysomnography outcomes in these children were examined, including net postoperative changes in the apnea-hypopnea index (AHI), net postoperative changes in the minimum and mean oxygen saturation, the overall success rate for a postoperative AHI <1, and the overall success rate for a postoperative AHI <5. Results Six studies with 41 patients were analyzed (mean age, 5.0 years; 55% boys; mean sample size, 6.8 patients). All children had PWS and received adenotonsillectomy for the treatment of OSA. The AHI was 13.1 events per hour (95% CI, 11.0-15.1) before surgery and 4.6 events per hour (95% CI, 4.1-5.1) after surgery. The mean change in the AHI was a significant reduction of 8.0 events per hour (95% CI, −10.8 to −5.1). The overall success rate was 21% (95% CI, 11%-38%) for a postoperative AHI <1 and 71% (95% CI, 54%-83%) for a postoperative AHI <5. Some patients developed velopharyngeal insufficiency postoperatively. Conclusion Adenotonsillectomy was associated with OSA improvement among children with PWS. However, residual OSA was frequently observed postoperatively in these patients.

scholarly journals Multilevel Sleep Surgery Including the Palate in Nonsyndromic, Neurologically Intact Children with Obstructive Sleep Apnea

OTO Open ◽  
2019 ◽  
Vol 3 (2) ◽  
pp. 2473974X1985147
Author(s):  
Jason E. Cohn ◽  
George E. Relyea ◽  
Srihari Daggumati ◽  
Brian J. McKinnon
Keyword(s):  
Obstructive Sleep Apnea ◽  
Sleep Apnea ◽  
Tertiary Care ◽  
Case Series ◽  
T Test ◽  
Velopharyngeal Insufficiency ◽  
Apnea Hypopnea Index ◽  
Sleep Surgery ◽  
Obstructive Sleep ◽  
Neurologically Intact

Objective To examine the effects of multilevel sleep surgery, including palate procedures, on obstructive sleep apnea parameters in the pediatric population. Study Design A case series with chart review was conducted to identify nonsyndromic, neurologically intact pediatric patients who underwent either uvulectomy or uvulopalatopharyngoplasty as part of multilevel sleep surgery from 2011 through 2017. Setting A tertiary care, university children’s hospital. Subjects and Methods Unpaired Student t test was used to compare average pre- and postsurgical apnea-hypopnea index (AHI) and oxygen saturation nadir (OSN). Paired Student t test was used to compare the mean pre- and postsurgical AHI and OSN within the same patient for the effects of adenotonsillectomy (T&A) vs multilevel sleep surgery. Results In patients who underwent T&A previously, multilevel sleep surgery, including palate procedures, resulted in improved OSA severity in 6 (86%) patients and worsened OSA in 1 (14%) patient. Multilevel sleep surgery, including palate procedures, significantly decreased mean AHI from 37.98 events/h preoperatively to 8.91 events/h postoperatively ( P = .005). However, it did not significantly decrease OSN. Conclusion This study includes one of the largest populations of children in whom palate procedures as a part of multilevel sleep surgery have been performed safely with no major complications and a low rate of velopharyngeal insufficiency. Therefore, palatal surgery as a part of multilevel sleep surgery is not necessarily the pariah that we have traditional thought it is in pediatric otolaryngology.

Postoperative Changes in Sleep-disordered Breathing and Sleep Architecture in Patients with Obstructive Sleep Apnea

2014 ◽  
Vol 120 (2) ◽  
pp. 287-298 ◽  
Author(s):  
Frances Chung ◽  
Pu Liao ◽  
Balaji Yegneswaran ◽  
Colin M. Shapiro ◽  
Weimin Kang
Keyword(s):  
Obstructive Sleep Apnea ◽  
Sleep Apnea ◽  
Sleep Disordered Breathing ◽  
Slow Wave Sleep ◽  
Sleep Architecture ◽  
Secondary Outcome ◽  
Apnea Hypopnea Index ◽  
Postoperative Changes ◽  
Obstructive Sleep ◽  
Disordered Breathing

Abstract Background: Anesthetics, analgesics, and surgery may profoundly affect sleep architecture and aggravate sleep-related breathing disturbances. The authors hypothesized that patients with preoperative polysomnographic evidence of obstructive sleep apnea (OSA) would experience greater changes in these parameters than patients without OSA. Methods: After obtaining approvals from the Institutional Review Boards, consented patients underwent portable polysomnography preoperatively and on postoperative nights (N) 1, 3, 5, and 7 at home or in hospital. The primary and secondary outcome measurements were polysomnographic parameters of sleep-disordered breathing and sleep architecture. Results: Of the 58 patients completed the study, 38 patients had OSA (apnea hypopnea index [AHI] &gt;5) with median preoperative AHI of 18 events per hour and 20 non-OSA patients had median preoperative AHI of 2. AHI was increased after surgery in both OSA and non-OSA patients (P &lt; 0.05), with peak increase on postoperative N3 (OSA vs. non-OSA, 29 [14, 57] vs. 8 [2, 18], median [25th, 75th percentile], P &lt; 0.05). Hypopnea index accounted for 72% of the postoperative increase in AHI. The central apnea index was low (median = 0) but was significantly increased on postoperative N1 in only non-OSA patients. Sleep efficiency, rapid eye movement sleep, and slow-wave sleep were decreased on N1 in both groups, with gradual recovery. Conclusions: Postoperatively, sleep architecture was disturbed and AHI was increased in both OSA and non-OSA patients. Although the disturbances in sleep architecture were greatest on postoperative N1, breathing disturbances during sleep were greatest on postoperative N3.

Predictors of Surgical Outcomes of Uvulopalatopharyngoplasty for Obstructive Sleep Apnea Hypopnea Syndrome

2011 ◽  
Vol 145 (6) ◽  
pp. 1049-1054 ◽  
Author(s):  
Yuan Ping Xiong ◽  
Hong Liang Yi ◽  
Shan Kai Yin ◽  
Li Li Meng ◽  
Xu Lan Tang ◽  
...  
Keyword(s):  
Obstructive Sleep Apnea ◽  
Lipid Metabolism ◽  
Sleep Apnea ◽  
Oxygen Saturation ◽  
Success Rate ◽  
Surgical Outcomes ◽  
Apnea Hypopnea Index ◽  
Glucose And Lipid Metabolism ◽  
Obstructive Sleep ◽  
Hypopnea Syndrome

Objectives. To investigate predictors of surgical outcomes of uvulopalatopharyngoplasty (UPPP) for obstructive sleep apnea hypopnea syndrome (OSAHS). Study Design. Case series with planned data collection. Setting. A university medical center. Subjects and Methods. Thirty-nine patients with OSAHS received Z-palatopharyngoplasty (ZPPP) or Han-uvulopalatopharyngoplasty (H-UPPP). All patients were evaluated within 3 months before surgery and at 6 to 12 months after surgery. Statistical analyses were conducted on preoperative parameters that could have affected surgical efficacy and outcome. Success was defined as an apnea–hypopnea index (AHI) fewer than 20 times per hour and a decrease of more than 50%. Results. The success rate was 56.4% (22/39 patients). There were statistically significant differences in AHI, lowest oxygen saturation (L-Sao2), time with oxygen saturation less than 90% (CT90), percentage of time with oxygen saturation less than 90% (CT90%), microarousal index (MI), apolipoprotein E (ApoE), high-density lipoprotein (HDL), fasting blood glucose (FBG), and Friedman OSA stage between the treatment success and failure groups. Higher success rate was predicted by lower severity, as indicated by lower AHI, CT90, CT90%, and MI; higher L-Sao2; and fewer glucose and lipid metabolism abnormalities, shown by lower ApoE and FBG and higher HDL. Conclusions. Disease severity, glucose and lipid metabolism, and Friedman OSA stage may be important predictors of surgical outcome of UPPP for OSAHS.

scholarly journals Multilevel Surgery in Moderate to Severe Obstructive Sleep Apnea Patients

2014 ◽  
Vol 6 (3) ◽  
pp. 87-91
Author(s):  
Jumroon Tungkeeratichai ◽  
Navarat Apirakkittikul ◽  
Somyos Kunachak
Keyword(s):  
Obstructive Sleep Apnea ◽  
Sleep Apnea ◽  
Wound Dehiscence ◽  
Velopharyngeal Insufficiency ◽  
Apnea Hypopnea Index ◽  
Severe Obstructive Sleep Apnea ◽  
Multilevel Surgery ◽  
Obstructive Sleep ◽  
Lateral Pharyngoplasty ◽  
Results Of Surgery

ABSTRACT Objective The aim of this study was to investigate the objective and subjective effectiveness of multilevel surgery, i.e. combined lingualplasty with new technique of partial posterior glossectomy (PPG) and uvulopalatopharyngoplasty in moderate to severe obstructive sleep apnea (OSA) patients. Study design and setting Retrospective study of 60 OSA patients undergoing multilevel surgery for the treatment of moderate to severe OSA. Results Preoperative mean apnea hypopnea index (AHI) was 57.5 events/h and preoperative mean lowest SpO2 was 79.1%. After multilevel surgery, postoperative mean AHI significantly decreased to 29.7 events/h (p < 0.001) and postoperative mean lowest SpO2 increased to 84.4% (p < 0.001). Patients had postoperative followup assessments for 1 to 3 years. Results of surgery was classified as curative in 35/60 (58.3%) of patients, and as effective, i.e. postoperative AHI less than preoperative AHI in 52/60 patients (86.7 %). Surgery was ineffective in 8/60 (13.3%) patients. Early postoperative complications comprised early velopharyngeal insufficiency (VPI) 20% (12/60), dysarthria 20% (12/60) and wound dehiscence 3.33% (2/60) but without serious complications after 1 year. Conclusion Combined lingualplasty (with new PPG) and uvulopalatopharyngoplasty (UPPP) as multilevel surgery can be an effective treatment of choice for patients with moderate to severe OSA. No mediumterm serious complication was found. Keywords Apnea hypopnea index, Glossectomy, Lateral pharyngoplasty, Multilevel surgery in obstructive sleep apnea, Obstructive sleep apnea, Uvulopalatoplasty. How to cite this article Tungkeeratichai J, Apirakkittikul N, Kunachak S. Multilevel Surgery in Moderate to Severe Obstructive Sleep Apnea Patients. Int J Otorhinolaryngol Clin 2014;6(3):8791.

Polysomnographic Outcomes Before and After Skeletal Surgeries for the Treatment of Obstructive Sleep Apnea

2021 ◽  
Vol 104 (3) ◽  
pp. 445-452
Keyword(s):  
Obstructive Sleep Apnea ◽  
Sleep Apnea ◽  
Apnea Hypopnea Index ◽  
Success Rates ◽  
Maxillomandibular Advancement ◽  
Obstructive Sleep ◽  
Before And After ◽  
Hyoid Suspension ◽  
Group 2 ◽  
Osa Treatment

Objective: To evaluate polysomnographic (PSG) outcomes after common skeletal surgeries for the treatment of obstructive sleep apnea (OSA) in Thai patients. Materials and Methods: The retrospective study included OSA patients aged 18 years and older treated by hyoid suspension (HS) plus uvulopalatopharyngoplasty (UPPP) (Group 1), genioglossus advancement (GA) plus tongue base radiofrequency (TBRF) (Group 2), and maxillomandibular advancement (MMA) (Group 3) at Siriraj Hospital between January 2007 and October 2018. Those with incomplete PSG data were excluded. The primary outcome was the apnea-hypopnea index (AHI). Secondary outcomes were other PSG parameters and postoperative complications. Results: Twenty-four patients including 22 males and 2 females were included. Group1 (n=11), median AHI decreased from 45.4 to 24.1 events/hour (p=0.17), while lowest oxygen saturation (LSAT) changed from 72.0% to 71.0% (p=0.11). Group2 (n=3) median AHI decreased from 64.7 to 51.4 events/hour (p=0.11), LSAT increased from 76.0% to 79.0% (p=1.0), and rapid eye movement (REM) sleep increased from 0.0% to 12.4% (p=0.11). Group3 (n=12) median AHI decreased from 68.5 to 7.8 events/hour (p<0.002), LSAT increased from 75.5% to 88.0% (p=0.04), and REM increased from 0.0% to 21.5% (p=0.01). Surgical success rates as defined by Sher’s criteria or a postoperative AHI of less than five events/hour were 44.4%, 33.3%, and 66.6% in patients in groups 1, 2, and 3, respectively. Common surgical complications included bleeding, mental or perioral paresthesia, and malocclusion after MMA. Conclusion: The skeletal surgeries significantly improved some PSG parameters, and thus may be viable options for OSA treatment in Thai patients. Keywords: Obstructive sleep apnea, Skeletal surgery, Hyoid suspension, Genioglossus advancement, Maxillomandibular advancement, Thai

scholarly journals Obstructive Sleep Apnea in Women: Specific Issues and Interventions

2016 ◽  
Vol 2016 ◽  
pp. 1-9 ◽  
Author(s):  
Alison Wimms ◽  
Holger Woehrle ◽  
Sahisha Ketheeswaran ◽  
Dinesh Ramanan ◽  
Jeffery Armitstead
Keyword(s):  
Obstructive Sleep Apnea ◽  
Sleep Apnea ◽  
Correct Diagnosis ◽  
Upper Airway ◽  
Fat Distribution ◽  
Apnea Hypopnea Index ◽  
Optimal Care ◽  
Obstructive Sleep ◽  
Osa Treatment ◽  
Degrees Of Severity

Obstructive sleep apnea (OSA) has traditionally been seen as a male disease. However, the importance of OSA in women is increasingly being recognized, along with a number of significant gender-related differences in the symptoms, diagnosis, consequences, and treatment of OSA. Women tend to have less severe OSA than males, with a lower apnea-hypopnea index (AHI) and shorter apneas and hypopneas. Episodes of upper airway resistance that do not meet the criteria for apneas are more common in women. Prevalence rates are lower in women, and proportionally fewer women receive a correct diagnosis. Research has also documented sex differences in the upper airway, fat distribution, and respiratory stability in OSA. Hormones are implicated in some gender-related variations, with differences between men and women in the prevalence of OSA decreasing as age increases. The limited data available suggest that although the prevalence and severity of OSA may be lower in women than in men, the consequences of the disease are at least the same, if not worse for comparable degrees of severity. Few studies have investigated gender differences in the effects of OSA treatment. However, given the differences in physiology and presentation, it is possible that personalized therapy may provide more optimal care.

scholarly journals Obstructive Sleep Apnea: Emerging Treatments Targeting the Genioglossus Muscle

2019 ◽  
Vol 8 (10) ◽  
pp. 1754 ◽  
Author(s):  
Olga Mediano ◽  
Sofia Romero-Peralta ◽  
Pilar Resano ◽  
Irene Cano-Pumarega ◽  
Manuel Sánchez-de-la-Torre ◽  
...  
Keyword(s):  
Obstructive Sleep Apnea ◽  
Sleep Apnea ◽  
Muscle Tone ◽  
Treatment Strategies ◽  
Upper Airway ◽  
Apnea Hypopnea Index ◽  
Compensatory Response ◽  
Dilator Muscle ◽  
Obstructive Sleep ◽  
Osa Treatment

Obstructive sleep apnea (OSA) is characterized by repetitive episodes of upper airway obstruction caused by a loss of upper airway dilator muscle tone during sleep and an inadequate compensatory response by these muscles in the context of an anatomically compromised airway. The genioglossus (GG) is the main upper airway dilator muscle. Currently, continuous positive airway pressure is the first-line treatment for OSA. Nevertheless, problems related to poor adherence have been described in some groups of patients. In recent years, new OSA treatment strategies have been developed to improve GG function. (A) Hypoglossal nerve electrical stimulation leads to significant improvements in objective (apnea-hypopnea index, or AHI) and subjective measurements of OSA severity, but its invasive nature limits its application. (B) A recently introduced combination of drugs administered orally before bedtime reduces AHI and improves the responsiveness of the GG. (C) Finally, myofunctional therapy also decreases AHI, and it might be considered in combination with other treatments. Our objective is to review these therapies in order to advance current understanding of the prospects for alternative OSA treatments.

scholarly journals The Relationship between Diabetes-Related Complications and Obstructive Sleep Apnea in Type 2 Diabetes

2018 ◽  
Vol 2018 ◽  
pp. 1-9 ◽  
Author(s):  
Nantaporn Siwasaranond ◽  
Hataikarn Nimitphong ◽  
Areesa Manodpitipong ◽  
Sunee Saetung ◽  
Naricha Chirakalwasan ◽  
...  
Keyword(s):  
Type 2 Diabetes ◽  
Obstructive Sleep Apnea ◽  
Sleep Apnea ◽  
Apnea Hypopnea Index ◽  
Obstructive Sleep ◽  
Lower Egfr ◽  
Osa Treatment ◽  
Severe Degree ◽  
The Relationship

This study explored the relationship between obstructive sleep apnea (OSA) and the presence of any diabetes-related complications in type 2 diabetes and whether this was mediated by hypertension. Secondly, the relationship between OSA severity and estimated glomerular filtration rate (eGFR) was investigated. A total of 131 patients participated. OSA was diagnosed using a home monitor, and severity was measured by apnea-hypopnea index (AHI) and oxygen desaturation index (ODI). OSA was found in 75.6% of the participants, 40.5% with moderate-to-severe degree. Any diabetes-related complications (retinopathy, neuropathy, nephropathy, or coronary artery disease) were present in 55.5%, and 70.2% of the participants had hypertension. Mediation analysis indicated that, compared to those with mild or no OSA, those with moderate-to-severe OSA were 3.05 times more likely to have any diabetes-related complications and that this relationship was mediated by the presence of hypertension. After adjusting for confounders, ODI (B = −0.036,p=0.041), but not AHI, was significantly associated with lower eGFR. In conclusion, moderate-to-severe OSA was related to the presence of any diabetes-related complications in type 2 diabetes, and the relationship was mediated by hypertension. The severity of intermittent hypoxia was associated with lower eGFR. Whether OSA treatment will delay or reduce diabetes-related complications should be investigated.

Modified Genioglossus Advancement and Uvulopalatopharyngoplasty in Patients with Obstructive Sleep Apnea

2011 ◽  
Vol 145 (5) ◽  
pp. 865-871 ◽  
Author(s):  
Tarek Abdelzaher Emara ◽  
Tharwat Abdelzaher Omara ◽  
Waheed Mohamed Shouman
Keyword(s):  
Obstructive Sleep Apnea ◽  
Sleep Apnea ◽  
Success Rate ◽  
Apnea Hypopnea Index ◽  
Genioglossus Muscle ◽  
Mandible Fracture ◽  
Obstructive Sleep ◽  
Significant Difference ◽  
Nocturnal Polysomnography ◽  
Postoperative Findings

Objective. To describe modification of the originally described genioglossus muscle advancement and its clinical assessment in the treatment of patients with obstructive sleep apnea. Study Design. Prospective study. Setting. University medical hospital. Subjects and Methods. Twenty-three patients with obstructive sleep apnea underwent modified genioglossus muscle advancement with uvulopalatopharyngoplasty. All patients were evaluated before and 6 months after surgery by history taking, clinical examination, Epworth Sleepiness Scale evaluation, fiber-optic nasopharyngoscopy, cephalometry, panoramic X-ray, and nocturnal polysomnography. Results. Postoperative mean ± SD apnea-hypopnea index (AHI) decreased from 40.7 ± 17.4 to 15.4 ± 10.7 ( P = .00; 95% confidence interval [CI], 18.4 to 32.27). With a success rate defined as AHI <20 and a 50% decrease in AHI of the preoperative value, the surgical success rate was 86.9%. Cephalometry analysis showed a significant difference between preoperative and postoperative findings, including a posterior airway space that increased a mean ± SD from 8.1 ± 2.5 to 12.3 ± 3.7 mm ( P = .00; 95% CI, −5.89 to −3.0), position of the mandible to the cranial base (SNB degree) that increased from 77.3 ± 2.7 to 78.5 ± 1.3 ( P = .005; 95% CI, −2.11 to −0.4), and improved palatal parameters. The mean (SD) average depth of the osteotomy and genioglossus advancement was 11.8 ± 2.6 mm. None of the 23 patients had mandible fracture, aesthetic changes of the chin, or detachment of the advanced genioglossus muscle. Conclusion. The modification described in this technique permits complete and safe capture and advancement of the whole genioglossus muscle, leading to satisfactory expansion of the retrolingual airway without stripping, detachment of the advanced genioglossus muscle, mandible fracture, or aesthetic changes of the chin.

449 The Effects of Positional and Sleep Stage Dependency on Mandibular Advancement Device Treatment Outcome in Obstructive Sleep Apnea

SLEEP ◽  
2021 ◽  
Vol 44 (Supplement_2) ◽  
pp. A177-A178
Author(s):  
Chien-Feng Lee ◽  
Yunn-Jy Chen ◽  
Yu-Ching Chen ◽  
Ming-Tzer Lin ◽  
Pei-Lin Lee ◽  
...  
Keyword(s):  
Obstructive Sleep Apnea ◽  
Sleep Apnea ◽  
Sleep Stage ◽  
Mandibular Advancement Device ◽  
Mandibular Advancement ◽  
Apnea Hypopnea Index ◽  
Obstructive Sleep ◽  
Treatment Naïve ◽  
Osa Treatment ◽  
The Relationship

Abstract Introduction Mandibular advancement device (MAD) responder phenotype are not well understood in patients with obstructive sleep apnea (OSA). Recent studies have reported the association between MAD treatment response and polysomnographic phenotypes using positional and sleep stage dependency, but with inconsistent findings. Thus, the study aims to investigate the relationship between the two phenotypes and MAD response. Methods This retrospective study recruited patients with OSA (apnea-hypopnea index [AHI] &gt;10/h), who were 20 to 80 years old, treatment naïve, and received MAD treatment for more than three months from 2009 to 2017. AHIsupine/AHInon-supine ≥2 and &lt;2 meant supine predominant (supine-p) and non-positional OSA, respectively. REM-AHI/NREM-AHI ≥2, ≤0.5, and between 0.5 to 2 indicated REM-predominant (REM-p), NREM-predominant (NREM-p), and stage-independent (SI) OSA, respectively. Three criteria defined successful MAD treatment (i.e., criterion 1: residual AHI &lt;5/h with &gt;50% reduction; criterion 2: residual AHI 50% reduction; criterion 3: reduction &gt;50%). The association between the two phenotypes and the three treatment criteria was identified using multivariable logistic regression. Results A total of 218 patients with a median age of 52.5 years, body mass index (BMI) of 25.4 kg/m2, and AHI of 28.2/h were recruited. Supine-p OSA had lower waist circumferences than non-positional OSA. The REM-p group had lower AHI and more female than the NREM-p and SI group. Supine-p OSA had better response than non-positional OSA (criterion 1: 43.2% vs 34.1%; criterion 2: 63.6% vs 34.1%; criterion 3: 77.3% vs 51.2%). NREM-p OSA had lower response across all three criteria (REM-p vs NREM-p vs SI: criterion 1: 57.6% vs 0% vs 42.0%; criterion 2: 75.8% vs 16.7% vs 56.5%; criterion 3: 75.8% vs 33.3% vs 77.1%). The odds of MAD response for supine-p OSA was 3.78 (95% CI = 1.44–9.93) to 3.98 (95% CI = 1.58–9.99)-fold than non-positional OSA while the odds for NREM-p OSA were 0.06 (95% CI = 0.01–0.58) to 0.15 (95% CI = 0.03–0.67)-fold than SI OSA after adjusting demographics and clinical features affecting MAD response. Conclusion Positional and sleep stage dependency were associated with MAD response and could be indicators for personal-tailored OSA treatment. Support (if any) The Ministry of Science and Technology, Taiwan (MOST 109-2314-B-002-252)

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