Biomedical subjects

S S Choi

Publications and source records attributed to S S Choi.

At least 19 recordsLinked to original sources

PubMed2006

Dual reporter genes enabling cell tracing with viable and reliable selection of various cell types.

Dual reporter genes driven by either a ubiquitous cytomegalovirus (CMV) or a neuro-specific tubulin alpha1 promoter (Talpha1) were constructed. The new genes, CMV (pCMV-GL) or Talpha1 promoter-driven GFP-LacZ (pTalpha1-GL), robustly expressed the fused GFP-LacZ protein reporting constitutive expressions in various cell types including CHO cells, loach and chicken embryos, and neuro-specific expression in differentiating mouse embryonic stem cells, respectively. The dual reporter genes thus provide a versatile tool for the studies of gene expression, cell lineage within the embryo and possibly the fate of stem cells in transplantation experiment, thus facilitating different analyses depending on the experimental purposes.

Animals↗

PubMed2006

Effects of Lactobacillus strains on cancer cell proliferation and oxidative stress in vitro.

AIMS: The objective of this study was to assess in vitro, whether heat-killed (HK) lactic acid bacteria cells and fractionations of HK cells could suppress the viability of human cancer cells and inhibit the cytotoxicity associated with oxidative stress. METHODS AND RESULTS: Among the strains, the HK cells of Lactobacillus acidophilus 606 and Lactobacillus casei ATCC 393 exhibited the most profound inhibitory activity in all of the tested cell lines. HK cells of L. acidophilus 606 were determined to be less toxic to healthy human embryo fibroblasts (hEF cells) than were HK cells of L. casei ATCC 393. The soluble polysaccharides from L. acidophilus 606 evidenced the most effective anticancer activity, but inhibited hEF cell growth by only 20%. The soluble polysaccharides from L. acidophilus 606 were partly observed to induce apoptosis in the HT-29 cells by DNA fragmentation and propidium iodine staining. Both the HK cells of L. acidophilus 606 and the soluble polysaccharide components of this strain also exhibited potent antioxidative activity. CONCLUSIONS: Our findings suggest that the soluble polysaccharide fraction from L. acidophilus 606 may constitute a novel anticancer agent, which manifests a high degree of selectivity for human cancer cells and antioxidative agent in the food industry. SIGNIFICANCE AND IMPACT OF THE STUDY: These soluble polysaccharide components from Lactobacillus may be applied to various foods, and used as adjuncts for cancer therapy and prevention.

Antineoplastic Agents↗

PubMed2003

Coronary artery spasm induced by carotid sinus stimulation during neck surgery.

We observed four transient episodes of marked ST-segment elevation in a 58-yr-old man with no history of coronary artery disease undergoing resection of a metastatic neck mass under general anaesthesia. Elevations of the ST segment were abrupt, with no change in arterial pressure or heart rate, and resolved spontaneously. When the carotid sinus was compressed directly, ST-segment elevation was noted 1 min after the onset of stimulation. After surgery, coronary angiography showed diffuse, slight narrowing of the distal bed of the posterolateral branch of the right coronary artery. Ergonovine caused total occlusion of the posterolateral branch of the right coronary artery with chest pain and ST-segment elevation, confirming the diagnosis of variant angina. The coronary artery spasm seems to have been provoked by vagal activation from carotid sinus stimulation during general anaesthesia.

Anesthesia, General↗

PubMed2002

Fenofibrate lowers abdominal and skeletal adiposity and improves insulin sensitivity in OLETF rats.

The effect of peroxisome proliferator-activated receptor (PPAR)-alpha activators on the liver is well established, but the other effects on muscle and adipose tissue about lipid metabolism and insulin sensitivity are not clear. We investigated whether PPAR-alpha activation affects adiposity of skeletal muscle as well as adipose tissue and improves insulin sensitivity in spontaneous type 2 diabetes model, Otsuka Long-Evans Tokushima Fatty (OLETF) rats. Thirty-three weeks of aged, 20 male OLETF rats were divided into two groups. Control group (n=10) was fed with chow and treatment group (n=10) with chow contained fenofibrate for 7 weeks. At the age of 40 weeks, all rats were examined with MRI, intravenous glucose tolerance test, and then sacrificed for measurement of fat mass and RNA analyses. The total fat (the sum of subcutaneous, mesenteric, epididymal, and retroperitoneal fat pads) measured by dissection was significantly reduced in treatment group. The signal intensity of muscular adiposity was significantly decreased in treatment group. The mRNA levels of FAT/CD36 and mitochondrial carnitine palmitoyltransferase I (M-CPT I) in liver were remarkably increased. Fasting plasma insulin and leptin levels, insulin response after intravenous glucose loading and homeostasis model assessment insulin resistance (HOMA(IR)) index were lowered in treatment group. Fenofibrate increase mitochondrial fatty acid beta-oxidation in liver but not in skeletal muscle and lower the plasma levels of triglyceride and free fatty acid. It might result in reduction of adiposity of truncal adipose tissue and skeletal muscle. We suggest that reduction of adiposity in trunk and skeletal muscle might improve insulin sensitivity.

Abdomen↗

PubMed2001

Antinociceptive profiles of aspirin and acetaminophen in formalin, substance P and glutamate pain models.

Aspirin (ASA) is widely used oral analgesics and acts as an inhibitor of cyclo-oxygenase. Also, acetaminophen (APAP) is effective analgesics and may selectively inhibit brain prostaglandin synthetase. However, their mechanisms of action in CNS are poorly defined, although several authors have shown that the antinociceptive effects of ASA and APAP have different underlying mechanisms and play some possible roles on spinal nociceptive processing, such as inhibition of prostaglandin synthesis. To define and characterize antinociceptive profiles of ASA and APAP on various pain models, we performed intraplantar formalin injection test, intrathecal (i.t.) substance P (0.7 microg)-induced nociceptive response test, and i.t. glutamate (20 microg)-induced nociceptive response test after ASA or APAP (from 10 to 300 mg/kg) administered orally to the mouse. In the formalin test, ASA produced an antinociceptive effect during only the 2nd phase (20-40 min), but not the 1st phase (0-5 min), in a dose-dependent manner. However, APAP showed a dose-dependent antinociceptive effect during both phases of the formalin test. In addition, both ASA and APAP reduced nociceptive behavior induced by glutamate administered i.t. in a dose-dependent manner. In substance P-induced nociceptive response, APAP, but not ASA, showed antinociceptive effect in a dose-dependent manner. Our results suggest that ASA and APAP administered orally may be mediated by different nociceptive processing at the spinal cord level.

Acetaminophen↗

PubMed2001

Possible roles of JNK pathway in the regulation of hippocampal proenkephalin and immediate early gene expression induced by kainic acid.

Mitogen-activated protein kinases (MAPKs) may play crucial roles in the kainic acid (KA)-evoked excitotoxic effect and the regulation of transcription factors (e.g. c-Fos and c-Jun) in hippocampus, but their exact role in the regulation of KA-induced opioid peptides expression has not been well characterized in vivo. Therefore, we examined possible involvement of the phosphorylated form of JNK, as well as CREB, in the regulation of KA-induced proenkephalin and immediate early genes (IEGs) expression in the rat hippocampus. KA increased proenkephalin mRNA expression in rat hippocampus, which was decreased by pre-administration with cycloheximide (CHX, a protein synthesis inhibitor). KA alone increased c-fos as well as c-jun mRNA levels. CHX further enhanced KA-induced c-fos and c-jun mRNA levels. Additionally, KA increased the phosphorylation of JNK, especially JNK1, which was attenuated by CHX. CHX decreased KA-induced c-Fos protein expression. Interestingly, CHX itself increased the phosphorylation of CREB, which was abolished by KA administration. Our results suggest that the phosphorylation of JNK is involved in the up-regulation of the proenkephalin gene expression via c-Fos and c-Jun that is induced by KA in rat hippocampus. However, the phosphorylation of CREB is not associated with the up-regulation of the proenkephalin mRNA level induced by KA in the rat hippocampus.

Animals↗

PubMed2001

Differential roles of spinal cholera toxin- and pertussis toxin-sensitive G proteins in nociceptive responses caused by formalin, capsaicin, and substance P in mice.

The aim of the present study is to characterize the roles of spinal cholera toxin (CTX)- and pertussis toxin (PTX)-sensitive G proteins in the regulation of various nociceptive responses. The effects of intrathecal (i.t.) pretreatments with CTX and PTX on the formalin (subcutaneous)-, capsaicin (i.t.)-, and substance P (SP; i.t.)-induced nociceptive behaviours were examined in mice. Pretreatment with CTX (i.t.; 24 h before) significantly and dose-dependently (0.05-0.5 microg) suppressed both the first and second phases of the formalin-induced nociceptive behaviour. On the other hand, pretreatment with PTX (i.t., 6 days before) at the same doses (0.05-N0.5 microg) did not affect the formalin-induced response. Capsaicin (i.t., 0.5 microg)- and SP (i.t., 0.7 microg)-induced nociceptive behaviours were attenuated by the pretreatment with CTX. In addition, SP-induced nociceptive response was also attenuated by the pretreatment with PTX. However, the capsaicin-induced nociceptive response was not influenced by PTX pretreatment. These findings suggest that, at the spinal cord level, CTX-sensitive G-proteins are involved in the formalin-, capsaicin-, and SP-induced nociceptive behavioural responses, whereas PTX-sensitive G proteins are involved in SP-induced nociceptive response.

Animals↗

PubMed2001

The effect of intranasal fentanyl on the emergence characteristics after sevoflurane anesthesia in children undergoing surgery for bilateral myringotomy tube placement.

UNLABELLED: Children undergoing placement of bilateral myringotomy tubes (BMT) often exhibit pain-related behavior (agitation) in the postanesthesia care unit. We compared the emergence and recovery profiles of pediatric patients who received sevoflurane with or without supplementary intranasal fentanyl for BMT surgery. By using a prospective, double-blinded design, 150 children 6 mo to 5 yr of age, scheduled for routine BMT surgery, were anesthetized with sevoflurane (2%-3%) in a 60% N(2)O/O(2) gas mixture. Patients were randomized to receive equal volumes of intranasal saline (Control), 1 microg/kg fentanyl or 2 microg/kg fentanyl. A blinded observer evaluated each patient using a previously described 4-point agitation scale and the Steward recovery scale. Response to parental presence was observed after a score of six (full recovery) was achieved on the Steward recovery scale. There were no significant differences among the three groups regarding age, weight, surgeon, duration of anesthesia, or ear condition. Recovery times and emergence characteristic scores were not statistically different. Agitation scores were significantly reduced in the 2-microg/kg Fentanyl group as compared with the Control group (P = 0.012). Fentanyl 2 microg/kg is recommended to reduce the incidence of agitation seen in these patients. IMPLICATIONS: We examined the use of nasally administered fentanyl for the relief of agitation or discomfort after placement of bilateral myringotomy tubes in 150 children ages 6 mo to 5 yr using a prospective, double-blinded design. Fentanyl 2 microg/kg was found to reduce the incidence of agitation in these patients.

Administration, Intranasal↗

PubMed2001

Enhanced urinalysis improves identification of febrile infants ages 60 days and younger at low risk for serious bacterial illness.

OBJECTIVE: Investigators have sought to establish "low-risk" criteria to identify febrile young infants who can be observed safely without antibiotics. Previous studies have used criteria for standard urinalysis to identify suspected urinary tract infection; however, cases of urinary tract infection have been missed. Enhanced urinalysis, using hemocytometer cell count and Gram stain performed on uncentrifuged urine, has been shown to have greater sensitivity and negative predictive value than standard urinalysis. The objective of this study was to evaluate the ability of criteria that incorporate enhanced urinalysis to identify febrile young infants who are at low risk for serious bacterial illness (SBI). METHODS: Institutional guidelines were established in 1999 to evaluate in a retrospective cohort study infants who were </=60 days of age with temperature >/=38.0 degrees C. "Low-risk" criteria included 1) well appearance without focal infection (excluding otitis media); 2) no history of prematurity, illness, or previous antibiotics; 3) peripheral white blood cell count (WBC) between 5 and 15 000/mm(3); 4) absolute band count </=1500/mm(3); 5) cerebrospinal fluid WBC </=5/mm(3) with a negative Gram stain; 6) enhanced urinalysis with WBC </=9/mm(3) with a negative Gram stain; 7) stool WBC <5/high power field in infants with diarrhea; and 8) chest radiograph without lobar infiltrate(s) in infants with respiratory signs or symptoms. SBI was defined as a lobar infiltrate on chest radiograph or presence of a bacterial pathogen in blood, urine, cerebrospinal fluid, stool, or culture obtained from the soft tissue. The hospital records of all infants who presented to the emergency department for evaluation of fever after January 1999, including those who did not meet low-risk criteria, were reviewed; data were collected regarding history, physical examination, laboratory test results, treatment, and clinical course. RESULTS: During the study period, 434 infants presented to the emergency department for evaluation of fever. Thirty patients were excluded from additional analysis because of incomplete data; 60 patients were identified immediately as "not low risk" on the basis of history or physical examination. Of the 344 remaining infants, 127 were identified as "low risk" on the basis of laboratory criteria; 83 (65.4%) were observed without antibiotics. None of the "low-risk" infants had an SBI. A total of 217 well-appearing infants were classified as "not low risk" on the basis of laboratory criteria; 28 (12.9%) had an SBI. The overall incidence of SBI in infants with complete data was 10.1%, whereas the incidence of SBI in all "not low-risk" infants was 14.8%. The negative predictive value for the "Pittsburgh" criteria was 100% (95% confidence interval: 96.7%-100%); the sensitivity was 100% (95% confidence interval: 89.7%-100%). CONCLUSIONS: . The application of low-risk criteria using enhanced urinalysis improves identification of infants who are at low risk for SBI.

Age Factors↗

PubMed2001

A case of glaucoma associated with Sturge-Weber syndrome and Nevus of Ota.

The Sturge-Weber syndrome consists of a unilateral port-wine hemangioma of the skin along the trigeminal distribution and is accompanied by an ipsilateral leptomeningeal angioma. Glaucoma is present in approximately half of the cases. The Nevus of Ota is a melanocytic pigmentary disorder, most commonly involving the area innervated by the trigeminal nerve. Elevated intraocular pressure, with or without glaucomatous damage, is observed in 10% of the cases. We report the first case of glaucoma associated with Sturge-Weber syndrome and Nevus of Ota in Korea.

Antihypertensive Agents↗

PubMed2001

Short term surgical outcomes of modified deep sclerectomy with catgut implant.

We compared the effectiveness of and complications resulting from modified deep sclerectomy with catgut implant (modified-DSCI) with those of standard deep sclerectomy with collagen implant (DSCI) in the short term following surgery. In this retrospective study, standard-DSCI was performed on thirteen patients (17 eyes), and modified-DSCI was performed on seven patients (11 eyes). After dissection of a 5x5 mm sized superficial scleral flap, a 3x4 mm sized rectangular deep scleral flap was constructed in DSCI and a 2x3 mm sized triangular deep scleral flap in modified DSCI. A collagen implant was placed on the scleral bed in DSCI and # 0 CHROMIC Catgut Absorbable Suture was used in modified DSCI. The mean follow up was 11.0+/-6.1 months in DSCI and 9.3+/-4.7 months in modified DSCI. The mean preoperative intraocular pressure (IOP) was 38.6+/-10.9 mmHg in DSCI and 34.8+/-8.6 mmHg in modified DSCI. In the DSCI group, the IOP was 13.4+/-3.0 mmHg at final follow up, and was 11.4+/-3.2 mmHg in the modified DSCI group. The number of Nd:YAG goniopuncture was 3 cases (25%) in the modified DSCI group, and 3 cases (21.4%) in the DSCI group. The number of intraoperative microperforations was 3 in the DSCI group and 2 in the modified DSCI group. Temporary hypotony was encountered in 8 eyes (57.1%) of the DSCI group and 4 eyes (50%) of the modified DSCI group. There was no significant difference observed between the two groups in regards to the effectiveness or rate of complications seen during short term follow up.

Adult↗

PubMed2000

Postsurgical follow-up of children with tympanostomy tubes: results of the American Academy of Otolaryngology-Head and Neck Surgery Pediatric Otolaryngology Committee National Survey.

Postsurgical follow-up of children with tympanostomy tubes is becoming a contentious issue in this era of managed care. Primary care providers believe themselves to be capable of evaluating these children. Otolaryngologists, on the other hand, have more specialized equipment available to them (suction apparatus, otomicroscopes, audiology devices, etc) for treating suppurative infections and monitoring the tympanic membrane for structural changes. In addition, the otolaryngologist is placed in an uncomfortable legal and ethical position if access to the patient with a tube-related complication is denied by the primary care provider. Attempts to develop an American Academy of Otolaryngology-Head and Neck Surgery (AAO-HNS) policy statement have been hampered by a lack of data on the incidence and severity of tube-related complications and the role that otolaryngologists can play in reducing these sequelae. A survey designed by the AAO-HNS Pediatric Otolaryngology Committee was distributed to 1000 board-certified otolaryngologists and all members of the American Society of Pediatric Otolaryngologists and the American Academy of Pediatrics-Otolaryngology Section regarding current practice patterns and practitioners' experiences with tympanostomy tube complications. Specific information regarding complications that could have been avoided with earlier otolaryngology referral was also obtained. The results of the survey and its implications for AAO-HNS policy are presented.

Aftercare↗

PubMed2000

Changing trends in neonatal subglottic stenosis.

OBJECTIVES: To determine whether there are any changes in the incidence and management of neonatal subglottic stenosis (SGS). METHODS: A retrospective chart review of 416 infants who were admitted to the neonatal intensive care unit of the Children's National Medical Center between July 1, 1995, and June 30, 1996, was carried out. The incidence of airway obstruction requiring anterior cricoid split or placement of tracheotomy tube was determined and compared with the incidence studied 10 years ago at the same institution. RESULTS: One of 416 neonates required surgical intervention for airway obstruction caused by SGS, for an overall neonatal SGS incidence of 0.24%. When only the neonates who were intubated for 48 hours or longer were considered, the incidence of SGS was 0.49% (1/204). In neonates who were intubated for 48 hours or longer and survived, the incidence of SGS was 0.63% (1/160). This is in comparison with the incidences of 0.65% (3/462), 1.5% (3/195), and 1.9% (3/159), respectively, seen in a study done at the Children's National Medical Center 10 years ago. Five infants in this current study required placement of a tracheotomy tube for reasons other than SGS. Two infants needed tracheotomy tube placement for micrognathia, and 3 others for central hypotonia, an omphalocele that required multiple surgical procedures, and choanal atresia with a serious heart anomaly, which was a manifestation of CHARGE association. None of these 5 infants had evidence of SGS at rigid endoscopy preceding the tracheotomy tube placement. CONCLUSION: The incidence and management of neonatal SGS remain unchanged during this study period when compared with those of 10 years ago.

Airway Obstruction↗

PubMed2000

Purification and characterization of a highly stable tyrosinase from Thermomicrobium roseum.

Tyrosinase, with an isoelectric point at pH 4.9, was purified to electrophoretic homogeneity from an extremely thermophilic bacterium, Thermomicrobium roseum. Gel filtration, N-terminal amino acid sequencing and SDS/PAGE analysis indicate that T. roseum tyrosinase is composed of two identical subunits, each with a molecular mass of 43000 Da. The enzyme exhibited high substrate specificity towards catechol, chlorogenic acid, L-3-(3,4-dihydroxyphenyl)-L-alanine (L-DOPA) and pyrogallol. The K(m) value of the enzyme for L-DOPA was 0.18 mM. beta-Mercaptoethanol and sodium diethyldithiocarbamate notably inhibited the enzymic activity. The activity of the enzyme was optimal at pH 9.5 and 70 degrees C, and was increased by addition of 1 mM Mg(2+), K(+) or Cu(2+). The enzyme was highly stable against high temperature and guanidine hydrochloride. The N-terminal amino acid sequence of the enzyme was determined to be Asp-Ile-Asn-Gly-Gly-Gly-Ala-Thr-Leu-Pro-Gln-Lys-Leu-Tyr. These facts indicate that T. roseum tyrosinase appears to be distinct from the tyrosinases so far purified from other sources.

Amino Acid Sequence↗

PubMed2000

Production and secretion patterns of cloned glucoamylase in plasmid-harboring and chromosome-integrated recombinant yeasts employing an SUC2 promoter.

To understand the differences in production and secretion patterns between plasmid-harboring and chromosome-integrated recombinant yeasts, the two recombinant Saccharomyces cerevisiae yeasts, containing the structural glucoamylase STA gene and the SUC2 promoter, were investigated. Both systems were regulated by glucose concentration in the culture broth. First, the glucoamylase activity per gene copy number of the chromosome-integrated recombinant yeast was 2.8- to 5.6-fold higher than that of the plasmid-harboring recombinant yeast. Overburdened owing to high copy number, the plasmid-harboring recombinant yeast gave lower glucoamylase activity per gene copy number. Second, the efficiency of signal sequence was compared; the secretion efficiency of glucoamylase in the plasmid-harboring recombinant yeast was higher than that in the chromosome-integrated recombinant yeast at 96 h of cultivation (74 vs 65%). We postulated that the higher level of secretion efficiency of the plasmid-harboring recombinant yeast resulted because the production level did not reach the capacity of the secretory apparatus of the host yeast. However, the specific secretion rate was much higher in the chromosome-integrated recombinant yeast even though the final secretion efficiency was lower. The lower secretion rate in the plasmid-harboring recombinant yeast could be explained by an adverse effect caused by higher production rate. Finally, the optimal glucose concentration for glucoamylase production in the chromosome-integrated recombinant yeast culture was lower than that in the plasmid-harboring recombinant yeast culture owing to gene dosage effect.

Cell Division↗

PubMed1999

Chromosomal localization of ESTs obtained from human fetal liver via BAC-mediated FISH mapping.

A total of 55 expressed sequence tags (ESTs) randomly chosen from our collection of fetal liver ESTs were mapped to chromosomes by fluorescence in situ hybridization (FISH) mapping techniques. To generate FISH mapping probes, the genomic DNAs for each EST were selected by screening an arrayed human bacterial artificial chromosome (BAC) library. In total, 73 BACs were used for mapping of the 55 ESTs. Among them, 70 BACs representing 52 ESTs unequivocally mapped to single chromosomal regions. The remaining 3 BACs representing 3 ESTs were localized to multiple regions, suggesting that BACs may have very low chimerism. Our mapping results were compared with EST mapping databases deposited in NCBI. Thirty-six of 55 ESTs corresponded to previously mapped positions of ESTs, 2 ESTs mapped to different positions from previously determined ones, and it was found that 17 ESTs have been mapped on new locations from this study. These mapping data may be used for completing the framework of the human physical map, and also for providing a good starting point for searching disease-related genes.

Blotting, Southern↗

PubMed1999

Pitfalls in laryngotracheal reconstruction.

OBJECTIVE: To determine the causes of laryngotracheal reconstruction (LTR) failures. DESIGN: Retrospective chart review. SETTING: Tertiary care children's hospital. PATIENTS: Seventeen pediatric patients who underwent revision LTR from October 1, 1986, to December 31, 1998. INTERVENTION: Laryngotracheal reconstruction. MAIN OUTCOME MEASURE: Decannulation. RESULTS: Seventeen patients required a total of 42 LTRs for decannulation. There were 17 primary LTRs and 25 revision LTRs. The primary LTRs were done either at our or other institutions. Two patients died after initial LTR failed, one because of tracheotomy tube plugging and the other because of a severe respiratory syncytial virus pneumonia. All 15 remaining patients have been decannulated. There were 27 failed LTRs with 17 being primary and 10 revision LTR failures. In 3 of the 27 failed procedures, no obvious causes for failure could be found. In the remaining 24 procedures, 1 or more factors that contributed to LTR failure could be found. Poor preoperative evaluation with subsequent failure to address the airway lesion was seen in 6 procedures. Intraoperative reasons for LTR failure included inappropriate choice of graft in 2 procedures; inappropriate stent in 7; inappropriate stent length in 1; and inappropriate duration of stent in 8. In 6 procedures, the airway abnormalities identified at endoscopy were not adequately addressed at LTR. Postoperative factors for failure were poor follow-up in 2, anterior suprastomal collapse in 2, and slipped or broken stent in 2. Other factors that contributed to LTR failures included intractable gastroesophageal reflux disease in 1 procedure and keloid formation in 5. CONCLUSIONS: Although some LTRs may fail secondary to factors that are not under the surgeon's control, many LTR failures can be avoided by accurate preoperative and intraoperative assessment of the stenosis, correct choice of surgical procedure, and close postoperative monitoring.

Adolescent↗

PubMed1999

Airway abnormalities in patients with Arnold-Chiari malformation.

OBJECTIVES: The goal was to determine the incidence and types of airway abnormalities in patients with Arnold-Chiari malformation (ACM). METHODS: The study was a retrospective chart review of 24 patients with ACM who were evaluated and treated between November 1991 and August 1997. RESULTS: Eighteen (75%) and 6 (25%) of the 24 patients had types I and II ACM, respectively. Three (12.5% of 24 patients) of the type II ACM patients had vocal cord impairment: 1 bilateral paralysis, 1 bilateral paresis, and 1 unilateral paralysis. None of the type I ACM patients had vocal cord impairment. Tracheotomy was necessary in 3 of the 24 patients and all in patients with type II ACM. Central sleep apnea was found in 5 of 6 type II ACM patients, but not in any of the type I ACM patients. CONCLUSIONS: Vocal cord impairment and sleep apnea were found in 12. 5% and 21%, respectively, of this ACM population. When type II ACM patients were considered separately, the incidences of vocal cord impairment and sleep apnea were 50% and 83%, respectively. Type II ACM patients tend to have a higher incidence of airway abnormalities and other neurologic dysfunctions. Flexible fiberoptic laryngoscopy is recommended in the airway evaluation of ACM patients. Early recognition, diagnosis, and management of these abnormalities may be lifesaving.

Adolescent↗