Photonic digital-to-analog conversion using a blue frequency chirp in a semiconductor optical amplifier.

In this Letter, we present a photonic digital-to-analog conversion (DAC) technique based on blue-chirp spectral slicing using a semiconductor optical amplifier (SOA). Because the gain change in an SOA leads to a refractive-index change based on the change in intensity of the input data signal, the probe signals experience a dynamic frequency shift to a shorter-wavelength side called a blue-chirp. After passing through the SOA, the probe signals corresponding to the logic level of the input digital signal are extracted by filtering only the blue-chirp component of the probe signals using rectangular-shape filters. In this study, we experimentally demonstrate a 10-Gb/s, 2-bit photonic DAC from a 10-Gb/s digital signal with various data patterns to a four-level amplitude signal assuming an analog signal. In addition, we evaluate the resolution performance of the photonic DAC in terms of differential and integral nonlinearities and an effective number of bits.

Three novel species of d-xylose-assimilating yeasts, Barnettozyma xylosiphila sp. nov., Barnettozyma xylosica sp. nov. and Wickerhamomyces xylosivorus f.a., sp. nov.

This study describes three novel xylose-assimilating yeasts, which were isolated from decayed wood collected from Bung Hatta Botanical Garden in West Sumatra and Cibodas Botanic Garden in West Java, or from litter from Eka Karya Bali Botanic Garden in Bali, Indonesia. Phylogenetic analysis was performed based on the sequences of the D1/D2 domains of the large ribosomal subunit (LSU), the small ribosomal subunit (SSU), the internal transcribed spacer (ITS) and elongation factor-1α (EF-1α), and the three strains were found to represent three novel species belonging to genera Barnettozyma or Wickerhamomyces. The morphological, biochemical and physiological characteristics indicated that the strains were distinct from other closely related species. Strains 13Y206T and 14Y196T belonging to the Barnettozyma clade are described as the type strains of Barnettozyma xylosiphila sp. nov. (type strain 13Y206T=NBRC 110202T=InaCC Y726T; MycoBank MB808598) and Barnettozyma xylosica sp. nov. (type strain 14Y196T=NBRC 111558T=InaCC Y1030T; MycoBank MB819485). Strain 14Y125T belonging to the Wickerhamomyces clade is described as the type strain of Wickerhamomyces xylosivorus f.a., sp. nov. (type strain 14Y125T=NBRC 111553T=InaCC Y1026T; MycoBank MB819484).

Pichia chibodasensis sp. nov., isolated in Indonesia.

Three strains (14Y260T, 14Y268 and 14Y276) of xylose-assimilating yeasts were isolated from decayed wood and soil collected in West Java in Indonesia. A phylogenetic analysis was performed based on the sequences of the D1/D2 domains of LSU, SSU and EF-1α, and the three strains were found to belong to the genus Pichia. The morphological, biochemical, physiological and chemotaxonomic characteristics indicated that these strains were distinct from other closely related species. Strains 14Y260T, 14Y268 and 14Y276 belonged to the Pichia clade and represent a novel species, named Pichia chibodasensis sp. nov. ; The type strain is 14Y260T (=NBRC 111569T=InaCC Y1042T).

Prevalence of obstructive sleep apnea syndrome in Japanese elementary school children aged 6-8 years.

PURPOSE: We aimed to determine the prevalence of and the risk factors for obstructive sleep apnea syndrome (OSAS) in Japanese children aged 6-8 years. METHODS: The parents of 202 children aged 6-8 years who attended a single elementary school in Shiga, Japan, were requested to complete the Child and Adolescent Sleep Checklist (CASC) and perform home Type 3 portable monitoring of their children. By using the CASC data and monitor recordings, we estimated the prevalence of pediatric OSAS with the help of different diagnostic criteria and identified the risk factors associated with OSAS. RESULTS: Complete data were obtained from 170 of the 194 children whose parents participated in the study. The mean total apnea-hypopnea index and obstructive apnea hypopnea index were 1.4 ± 1.3 and 0.4 ± 0.6 h(-1), respectively, and central apnea was the most prevalent type of respiratory event, accounting for 70.4% of all events. The overall prevalence of OSAS ranged from 0.6% to 43.5%, depending on the cutoff value used, and was 3.5% when using International Criteria of Sleep Disorders version II (ICSD II) diagnostic criteria. The presence of tonsillar hypertrophy was the only parameter whose prevalence was significantly elevated in children with OSAS across all diagnostic criteria. CONCLUSIONS: The prevalence of pediatric OSAS varies according to the diagnostic criteria used, indicating the need for further research focusing on outcomes to define a clinically significant diagnostic threshold. The presence of tonsillar hypertrophy is an important risk factor in the development of pediatric OSAS.

Obstructive sleep apnea in Asian primary school children.

PURPOSE: The objectives of this study were to examine the prevalence of obstructive sleep apnea (OSA) in primary school children, relationships between OSA and tonsillar hypertrophy, adenoid, and patency of the nasal cavity, and the effects of the tonsillar hypertrophy and adenoid on the nasal patency. METHODS: An examination of the palatine tonsils and anterior rhinoscopy, completion of a questionnaire survey, a measurement of nasal resistance, an examination for sleep apnea at home using portable polysomnography device, and radiography of pharyngeal tonsil were performed in 152 primary school children. RESULTS: The obstructive apnea hypopnea index (O-AHI) increased with enlargements in the palatine tonsils. The adenoidal nasopharyngeal ratio (A/N ratio) decreased with advances in grade. A significant difference was observed in the O-AHI between those with and without adenoid. The median value of the O-AHI increased with advances in grade. The nasal resistance was significantly higher in the group with adenoid compared as in the group without. It was also higher in the nasal disease group with OSA than in the group without. Full polysomnography(PSG) was recommended in 16 (10.5%) of 152 who underwent the examination using the portable polysomnography device, and of the eight who underwent PSG, six (75%) were confirmed to have OSA, while its prevalence in all subjects was estimated as 7.9%. CONCLUSIONS: Disturbances in nasal respiration as well as tonsillar hypertrophy and adenoid were found to be a risk factor of OSA in primary school children.

TG1 integrase-based system for site-specific gene integration into bacterial genomes.

Serine-type phage integrases catalyze unidirectional site-specific recombination between the attachment sites, attP and attB, in the phage and host bacterial genomes, respectively; these integrases and DNA target sites function efficiently when transferred into heterologous cells. We previously developed an in vivo site-specific genomic integration system based on actinophage TG1 integrase that introduces ∼2-kbp DNA into an att site inserted into a heterologous Escherichia coli genome. Here, we analyzed the TG1 integrase-mediated integrations of att site-containing ∼10-kbp DNA into the corresponding att site pre-inserted into various genomic locations; moreover, we developed a system that introduces ∼10-kbp DNA into the genome with an efficiency of ∼10(4) transformants/µg DNA. Integrations of attB-containing DNA into an attP-containing genome were more efficient than integrations of attP-containing DNA into an attB-containing genome, and integrations targeting attP inserted near the replication origin, oriC, and the E. coli "centromere" analogue, migS, were more efficient than those targeting attP within other regions of the genome. Because the genomic region proximal to the oriC and migS sites is located at the extreme poles of the cell during chromosomal segregation, the oriC-migS region may be more exposed to the cytosol than are other regions of the E. coli chromosome. Thus, accessibility of pre-inserted attP to attB-containing incoming DNA may be crucial for the integration efficiency by serine-type integrases in heterologous cells. These results may be beneficial to the development of serine-type integrases-based genomic integration systems for various bacterial species.

Enhancement of the enzymatic activity of Escherichia coli acetyl esterase by a double mutation obtained by random mutagenesis.

A double mutant of Escherichia coli acetyl esterase (EcAE) with enhanced enzymatic activity was obtained by random mutagenesis using error-prone PCR and screening for enzymatic activity by observing halo formation on a tributyrin plate. The mutant contained Leu97Phe (L97F) and Leu209Phe (L209F) mutations. Single mutants L97F and L209F were also constructed and analyzed for kinetic parameters, as well as double mutant L97F/L209F. Kinetic analysis using p-nitrophenyl butyrate as substrate indicated that the k(cat) values of L97F and L97F/L209F were larger than that of the wild-type enzyme, by 8.3-fold and 12-fold respectively, whereas no significant change was observed in the k(cat) value of L209F. The K(m) values of L209F and L97F/L209F were smaller than that of the wild-type enzyme, by 2.9-fold and 2.4-fold respectively, whereas no significant change was observed in the K(m) value of L97F. These results indicate that a combination of an increase in k(cat) values due to the L97F mutation and a decrease in K(m) value due to the L209F mutation renders the k(cat)/K(m) value of the double mutant enzyme 29-fold higher than that of the wild-type enzyme.

Intestinal immune-potentiation by a purified alkylglycerols compound.

Alkylglycerols have shown immune stimulant and adjuvant activity in several studies and the aim of the present research was to assess in particular the effect of shark liver-derived alkylglycerols on gut immune system. C57BL/6 mice, fed under specific pathogen free conditions, were randomly divided into two groups: (a) fed normal laboratory food or (b) added with alkylglycerols (2 mg/day/mouse) for 3 weeks. Intraepithelial lymphocytes (IEL) were retrieved from the small intestine and tested for NK and tumor cytotoxicity. Lymphocytes from liver, spleen and IEL were also assessed as for their counting and phenotypic characterization. Under supplementation with alkylglycerols, the number of lymphocytes yielded by the small intestine increased by to almost 40%. Moreover, the ratio of CD8alphabeta+TCRalphabeta+ cells/CD8alphaalpha+TCRalphabeta+ cells remarkably increased. In parallel with this reshaping in the distribution of lymphocyte subsets, tumor cytotoxicity of IEL against P815 cells and cytokine production from circulating lymphocytes were also enhanced. These data show that phylogenetically developed lymphocytes (CD8alphabeta, TCRalphabeta+) were significantly activated by the oral administration of alkylglycerols. The present results indicate that purified alkylglycerols might have such significant potential via the enhancement of intestinal immunity, especially in the small intestine.

Site-specific recombination system based on actinophage TG1 integrase for gene integration into bacterial genomes.

Phage integrases are enzymes that catalyze unidirectional site-specific recombination between the attachment sites of phage and host bacteria, attP and attB, respectively. We recently developed an in vivo intra-molecular site-specific recombination system based on actinophage TG1 serine-type integrase that efficiently acts between attP and attB on a single plasmid DNA in heterologous Escherichia coli cells. Here, we developed an in vivo inter-molecular site-specific recombination system that efficiently acted between the att site on exogenous non-replicative plasmid DNA and the corresponding att site on endogenous plasmid or genomic DNA in E. coli cells, and the recombination efficiencies increased by a factor of ~10(1-3) in cells expressing TG1 integrase over those without. Moreover, integration of attB-containing incoming plasmid DNA into attP-inserted E. coli genome was more efficient than that of the reverse substrate configuration. Together with our previous result that purified TG1 integrase functions efficiently without auxiliary host factors in vitro, these in vivo results indicate that TG1 integrase may be able to introduce attB-containing circular DNAs efficiently into attP-inserted genomes of many bacterial species in a site-specific and unidirectional manner. This system thus may be beneficial to genome engineering for a wide variety of bacterial species.

Hepatoprotective activity of a phytotherapeutic formula on thioacetamide--induced liver fibrosis model.

Hepatic fibrosis is a widespread alteration in the liver that primarily consists of increased collagen deposition in the tissue. The aim of the present study was to evaluate the protective effects of poly-phytocompound EH-1501 containing small amounts of silymarin but also other potentially effective substances on thioacetamide (TTA)-induced liver fibrosis and to elucidate the mechanisms underlying these protective effects in rats. Forty rats were randomly divided into four groups. Liver fibrosis was induced by intraperitoneal injection of 200 mg/kg body weight. TAA dissolved in saline was administered thrice a week, for 8 weeks. Groups 1 (normal healthy control) and 2 (liver injury model) received water for 8 weeks or silymarin (50 mg/kg p.o. daily) for 8 weeks (group 3) or a poly-phytocompound EH-1501 (containing grape leaf, wild strawberry, dandelion and milk thistle, EuroHealth, Italy) (200 mg/kg, daily respectively) for 8 weeks (group 4). Biochemistry and serum fibrosis markers were AST, ALT, GGT, bilirubin, thiobarbituric acid reactive substances (TBARs), hyaluronic acid and type IV collagen 7s. Liver tissue was used to assay glutathione peroxidase (GPx), catalase (CAT), superoxide dismutase (SOD), TBARs, hydroxyproline and gene expression of collagen alpha1 (col alpha1) and transforming growth factor-beta1 (TGF-beta1). Silymarine and EH-1501 were equally effective in reducing serum markers of liver damage and fibrosis as well as oxidative stress. However, as compared to silymarine, EH-1501 was significantly more effective in improving tissue level of GPx while decreasing TBARs and hydroproline content (p < 0.05). When looking at gene expression of col alpha1 and TGF-beta1, EH-1501 showed a significantly higher degree of gene down-regulation as compared to silymarine (p < 0.05). Taken altogether, these data suggest that a natural antioxidant-containing phytocompound EH-1501 exerts an effective hepatoprotective property in experimental chronic fibrotizing liver injury to a significantly higher degree than silymarin.

Functional optical hemodynamic imaging of the olfactory cortex.

OBJECTIVE: We used multichannel near-infrared spectroscopy (MNIRS) to monitor the activity of the frontal cortex as mirrored by hemodynamic responses subjected to olfactory stimulation. The aim of this study was to clarify the functional brain imaging of olfactory activity. STUDY DESIGN: Prospective study. METHODS: This study was conducted on eight healthy subjects aged from 22 to 39 years (4 men and 4 women; mean age, 28.8 yr). We used a 22-channel near-infrared spectroscopy device with eight light-incident fibers and seven detector fibers, each with an interoptode distance of 2.5 cm on the frontal region. Olfactory stimulation consisted of five repetitions, each lasting 5 seconds and followed by a 55 seconds rest period. Isovaleric acid was used as odor stimulation, and saline was used as a control. We measured the changes in concentrations of oxyhemoglobin [oxyHb], deoxyhemoglobin [deoxyHb], and total hemoglobin [totalHb] from prebaseline values. Furthermore, we divided the frontal cortex into four areas (right upper, left upper, right lower, left lower) and investigated the activity in each area. RESULTS: Isovaleric acid caused changes, especially in the lower area, but saline caused no changes. [oxyHb] and [totalHb] increased after odor stimulation, but [deoxyHb] did not change. These active areas may be related to the orbitofrontal cortex, corresponding to olfactory cortices. CONCLUSION: This study has shown that MNIRS enables evaluation of changes in hemodynamics related to brain activity by olfactory stimulation.

Preference evaluation and perceived sensory comparison of fluticasone furoate and mometasone furoate intranasal sprays in allergic rhinitis.

OBJECTIVE: Intranasal corticosteroid sprays (INCSs) are commonly used for therapy of allergic rhinitis (AR). Adherence to regular use of INCSs is influenced by patient perception and preferences of products. The study objective was to compare perceived sensory attributes of fluticasone furoate nasal spray (FFNS) and mometasone furoate nasal spray (MFNS) in AR patients. METHODS: In a multicenter, randomized, crossover, prospective study, 40 seasonal AR patients were administered both FFNS and MFNS for 2 weeks each in a crossover fashion, for a total of 4 weeks. Patients completed questionnaires for each product regarding perceived sensory attributes at the end of each two-week period of product administration. RESULTS: FFNS was significantly preferred over MFNS. Significantly, fewer subjects perceived a bitter taste (p=0.01), medication running down their throat (p=0.033), and medication running out of their nose (p=0.002) with FFNS. MFNS was more frequently reported to induce nasal irritation (p=0.012), sneezing (p=0.017), and rhinorrhea (p=0.007) compared to FFNS. Interestingly, these findings were markedly observed in females. Medicine dripping out of the nose and nasal shooting were the most common problems reported for MFNS with a higher proportion of subjects who felt moderate-to-severe discomfort. Overall, 52.5% of patients expressed a preference for FFNS compared with 22.5% for MFNS. CONCLUSION: Several perceived sensory attributes of FFNS were rated significantly superior to MFNS. FFNS may contribute to enhanced treatment outcomes in AR patients due to improved treatment adherence.

Obstructive sleep apnea in preschool-aged Japanese children - efficiency of screening using lateral neck radiography.

Conclusions The prevalence of obstructive sleep apnea (OSA) in preschool-aged children diagnosed by the International Classification of Sleep Disorders (ICSD) version 3 criteria was relatively higher than that diagnosed by ICSD-2. Although the assessment of the upper airway by lateral neck radiography was effective for detecting OSA in this age group, this assessment is not recommended for all children as a screening method because of parental concern related to radiation exposure. Objective This study investigated the prevalence of OSA and the screening capacity of lateral neck radiography in community-based preschool-aged children. Methods Parents of 211 children aged 3-6 years were requested to complete the sleep-related questionnaire. Subjects who agreed to further investigations were invited to undergo home type 3 portable monitoring and clinical examination, including radiography. We estimated the prevalence of OSA and evaluated the detection power of radiography for predicting OSA. Results One hundred and eighty-eight (89.1%) subjects completed the questionnaire and 67 (31.8%) agreed to further examinations. The weighted prevalence was 7.3% and 12.8% by ICSD-2 and 3, respectively. Area under the receiver operator curve for the adenoidal/nasopharyngeal and tonsil/pharyngeal ratios measured using radiography was slightly larger than that for tonsil size graded by visual inspection.

[Pollen dispersion of Japanese cedar and Japanese cypress in Kagawa Medical University of Kagawa Prefecture].

We installed the Durham sampler on the roof (27.4 m on the ground) of Kagawa Medical University in 1989 to survey pollen dispersion in Kagawa prefecture and have investigated the pollen survey from 1989 to 2001. We examined the correlation between the annual variations in the pollen counts of Japanese cedar (Cryptomeria japonica) and Cupressaceae, mainly Japanese cypress (Chamaecyparis obtusa) and annual changes in meteorological conditions. The sum of these pollen counts correlated with the highest temperature from 11 July to 10 August in Kagawa prefecture. However, it is difficult to determine the pollen dispersion only based on meteorological factors. Other factors giving influences on the pollen dispersion need to be further analyzed in the future.

Evaluation of adenotonsillectomy and tonsillectomy for pediatric obstructive sleep apnea by rhinomanometry and the OSA-18 questionnaire.

CONCLUSION: Nasal resistance and the OSA-18 score were useful for evaluating surgical treatments. The sleep disturbance score may also be useful for predicting the severity of obstructive sleep apnea (OSA) in children. OBJECTIVE: We evaluated the effect of surgery on children with OSA using polysomnography (PSG) parameters, nasal resistance, and the OSA-18 questionnaire, and also investigated the cut-off OSA-18 score to screen for pediatric OSA. METHODS: This was a retrospective study in which PSG parameters and nasal resistance were measured using a rhinomanometer and the OSA-18 score was obtained from the OSA-18 questionnaire before and after surgery in 45 children with OSA. RESULTS: The mean age of the 45 patients was 5.7 ± 2.0 years. The mean value of the obstructive apnea hypopnea index (O-AHI) improved from 16.2 ± 14.3/h before surgery to 1.1 ± 1.7/h after surgery, the mean nasal resistance improved from 0.44 ± 0.19 to 0.32 ± 0.10 Pa/cm(3)/s, and the mean OSA-18 score improved from 61.1 ± 13.7 to 30.4 ± 5.8, and all these improvements were significant. The O-AHI value was lower than 1/h after surgery in 64.4% of patients (29/45). The O-AHI value was significantly correlated with the sleep disturbance score (r = 0.352, p = 0.018). When the cut-off OSA-18 score for screening was set at 40, sensitivity was 100%.

Nasal resistance in Japanese elementary schoolchildren: determination of normal value.

CONCLUSION: Rhinomanometry is a useful method for evaluating nasal airway patency in schoolchildren, and we could confirm the validity of the results it produces. OBJECTIVE: Our purpose was to assess the validity nasal resistance measurements produced using anterior active rhinomanometry by comparing the results with those of our previous study and to determine a normal value of the nasal resistance. METHODS: Nasal resistance was measured by rhinomanometry in 852 children using the active anterior method. RESULTS: Mean nasal resistance was 0.45 ± 0.70 Pa/cm(3)/s. Nasal diseases were noted in 358 (42%) children, and nasal condition was normal (the normal group) in 494 (58%) children. Nasal resistance was 0.57 ± 1.05 Pa/cm(3)/s in the nasal disease group and 0.35 ± 0.16 Pa/cm(3)/s in the normal group, showing that resistance was significantly higher in the nasal disease group. In the normal nasal groups, nasal resistance tended to be lower in the children in higher grades (first grade, 0.44 ± 0.17 Pa/cm(3)/s; second grade, 0.37 ± 0.11 Pa/cm(3)/s; third grade, 0.36 ± 0.23 Pa/cm(3)/s; fourth grade, 0.36 ± 0.14 Pa/cm(3)/s; fifth grade, 0.30 ± 0.08 Pa/cm(3)/s; sixth grade, 0.29 ± 0.11 Pa/cm(3)/s), and taller groups (<120 cm, 0.43 ± 0.16 Pa/cm(3)/s; 120-130 cm, 0.37 ± 0.19 Pa/cm(3)/s; 130-140 cm, 0.34 ± 0.12 Pa/cm(3)/s; >140 cm, 0.28 ± 0.09 Pa/cm(3)/s). Results similar to those seen in our previous study were obtained in each group.

Measurement of nasal resistance by rhinomanometry in 892 Japanese elementary school children.

OBJECTIVE: The normal value of nasal resistance in adults has been reported (0.25 Pa/cm³/s), but that in children has not. In this study, we measured nasal resistance in Japanese school children by employing rhinomanometry. METHODS: An otolaryngologist examined 939 Japanese school children with regard to the presence or absence of nasal diseases and tonsil size. Nasal resistance was measured by rhinomanometry employing the active anterior method in 892 children. A questionnaire concerning the condition during sleep, such as the presence or absence of snoring and sleep apnea syndrome, was performed. RESULTS: The mean nasal resistance was 0.43 ± 0.50 Pa/cm³/s: 0.46 ± 0.65 and 0.39 ± 0.22 Pa/cm³/s in boys and girls, respectively. Of the 892 children, Grade 3 and 4 tonsil hypertrophy was noted in 84 (9%), but the presence of tonsil hypertrophy did not influence nasal resistance. Nasal diseases were noted in 335 children (38%) and the nasal condition was normal (the normal group) in 557 (62%). Nasal resistance was 0.56 ± 0.75 Pa/cm³/s in the nasal disease group and 0.36 ± 0.21 Pa/cm³/s in the normal group, showing that the resistance was significantly higher in the nasal disease group. The resistance tended to decrease as the school grade increased. In the normal group, 290 children (33%) experienced no problem regarding the upper airway, such as snoring and sleep apnea syndrome, based on a questionnaire, and nasal resistance was 0.35 ± 0.17 Pa/cm³/s. CONCLUSION: This normal nasal resistance value may be adopted for the objective evaluation of nasal obstruction and effects of treatment in pediatric nasal diseases.

Functional optical hemodynamic imaging of the olfactory cortex in normosmia subjects and dysosmia subjects.

CONCLUSION: These activated areas may be related to the orbitofrontal cortex, corresponding to olfactory cortices. This study shows that multichannel near-infrared spectroscopy (NIRS) enables the evaluation of brain activity of normosmia subjects and dysosmia subjects by olfactory stimulation. OBJECTIVE: Objective olfactory testing is not common. NIRS has beenused before to study functional activations in various areas of the brain, but we wanted to investigate the difference in brain olfactory activity in normosmia subjects and dysosmia subjects using multi-channel NIRS (MNIRS). SUBJECTS AND METHODS: This study was conducted on eight normosmia subjects and five dysosmia subjects. We employed a 22-channel near-infrared spectroscopy device with eight light incident fibers and seven light detector fibers, each with an inter-optode distance of 2.5 cm on the frontal head. Isovaleric acid was used as the odor stimulant. We measured the change in oxyhemoglobin concentrations [oxyHb], deoxyhemoglobin concentrations [deoxyHb], and total hemoglobin concentrations [totalHb] from pre-baseline values. Furthermore, we divided the frontal cortex into four areas (right upper, left upper, right lower, left lower) and measured the activity in each area. Then, the changes in [oxyHb], [deoxyHb], and [totalHb] of normosmia subjects and dysosmia subjects were compared in each area. RESULTS: In all normosmia subjects, isovaleric acid caused remarkable changes, especially in the lower areas of the frontal cortex. However, in all dysosmia subjects, isovaleric acid caused no changes.

Computed tomographic evaluation of anatomic relationship between the paranasal structures and orbital contents for endoscopic endonasal transethmoidal approach to the orbit.

OBJECTIVE: Some recent reports have described the endoscopic endonasal removal of orbital tumors. However, the surgical anatomy for an endoscopic endonasal approach has not yet been clearly described. The first aim of this study is to examine the anatomic relationship between the paranasal and orbital structures with the use of computed tomographic imaging and to find useful landmarks for a transethmoidal approach to the orbital retrobulbar space. The second aim is to determine a procedure to minimize the possibility of bleeding via the endonasal transethmoidal approach. METHODS: One hundred axial and coronal computed tomographic scans obtained between January 2004 and December 2005 were evaluated. RESULTS: The third lamella was located posteriorly to the posterior end of the eyeball on all axial computed tomographic scans, thus indicating that it may be a useful landmark for the localization of the retrobulbar space. There was a large variation in the relationship among the inferior and medial rectus muscles and the ethmoid-maxillary plate regarding their location. These results demonstrate that the route into the orbit via the ethmoid-maxillary plate gains no access to the medial side of the medial rectus muscle, the region with abundant blood vessels. CONCLUSION: These results suggest that the third lamella and ethmoid-maxillary plate are the most important anatomic landmarks for an endoscopic endonasal transethmoidal approach to the orbital retrobulbar space.

Removal of an orbital apex hemangioma using an endoscopic transethmoidal approach: technical note.

OBJECTIVE: The posterior orbit contains a number of important and vulnerable structures, including the optic nerve, the ophthalmic artery and vein, and the ocular muscles and their motor nerves, which makes surgical access to the lesion in this region quite difficult. Transfrontal, transfrontal-ethmoidal, and transmaxillary procedures have the disadvantage of possible injuries to a number of nontumor structures, whereas an endoscopic transethmoidal approach is a minimally invasive surgery for the retrobulbar lesions. Retrobulbar cavernous hemangioma was successfully removed by a transethmoidal approach. METHODS: Tumor removal was performed in a patient with an intraconal cavernous hemangioma of approximately 15 mm in diameter. By a transethmoidal approach, the medial-inferior part of the orbit, as well as the apex of the orbit, were clearly visualized after endonasal ethmoidectomy. After the removal of the medial orbital bone, the orbital periosteum was incised and elevated. By elevating the orbital fat, the tumor could be identified separately from the orbital contents. RESULTS: Cavernous hemangioma at the orbital apex was removed without complications. CONCLUSION: An endoscopic transethmoidal approach, which requires no skin incision, is a minimally invasive surgery for retrobulbar orbital tumor, leading to excellent cosmetic results with less bleeding.