Growth Behavior of Endothelial Cells According to Electrospun poly(D,L-Lactic-Co-Glycolic Acid) Fiber Diameter as a Tissue Engineering Scaffold

Investigating the effect of electrospun fiber diameter on endothelial cell proliferation provides an important guidance for the design of a fabric scaffold. In this study, we prepared biodegradable poly(D,L-lactic-co-glycolic acid) (PLGA) fibrous nonwoven mats with different fiber diameters ranged from 200 nm to 5 µm using the electrospinning technique. To control the fiber diameters of PLGA mats, 4 mixture solvents [hexafluoro-2-propanol, 2,2,2,-trifluoroethanol:dimethylformamide (9:1), 2,2,2,-trifluoroethanol:hexafluoro-2-propanol (9:1), chloroform] were used. Average diameters were 200 nm, 600 nm, 1.5 µm, and 5.0 µm, respectively. Stereoscopic structure and spatial characterization of fibrous PLGA mats were analyzed using atomic force microscopy and a porosimeter. The mechanical properties of PLGA mats were analyzed using a universal testing machine. The spreading behavior and infiltration of endothelial cells on PLGA mats were visualized by field emission scanning electron microscopy and hematoxylin and eosin staining. Cell proliferation on different PLGA fibers with different diameters was quantified using the MTT assay. Cells on 200 nm diameter PLGA mats showed rapid attachment and spreading. However, the cells did not penetrate the PLGA mat. Cells cultured on 600 nm and 1.5 µm diameter fibers could infiltrate the pores and cell proliferation was dramatically increased after 14 days. Secreted prostacyclin from endothelial cells on each mat was measured to examine the ability to inhibit platelet activation. This basic study on cell proliferation and fiber diameter with physical characterization provides a foundation for studies examining nonwoven fibrous PLGA mats as a tissue engineering scaffold.

The Relationship between the OCT Parameters and Visual Acuity after Occlusion Therapy in Hyperopic Anisometropic Amblyopia

PURPOSE: We measured the macular and peripapillary retinal nerve fiber layer (RNFL) thickness in patients with hyperopic anisometropic amblyopia using optical coherence tomography (OCT) to determine the relationship between final visual acuity after occlusion therapy and these OCT parameters. METHODS: This prospective study comprised 41 patients with unilateral hyperopic anisometropic amblyopia treated from April 2004 to August 2005. According to the final visual acuity after occlusion therapy, we divided our patients into two groups and compared the macular and peripapillary RNFL thicknesses between normal and amblyopic eyes. RESULTS: The mean refractive error was +4.3 diopters (D) in amblyopic eyes, and +1.3 D in normal eyes. The mean macular thickness of group A (patients with final visual acuity equal to or better than 20/25) and group B (patients with final visual acuity worse than 20/25) was 256.8+/-17.7 micrometer and 259.3+/-14.5 micrometer in amblyopic eyes, and 253.8+/-17.3 micrometer and 254.6+/-16.7 micrometer in normal eyes respectively. The mean peripapillary RNFL thickness of group A and group B was 118.6+/-12.9 micrometer and 111.5+/-9.0 micrometer in amblyopic eyes, and 112.9+/-9.2 micrometer and 108.3+/-6.5 micrometer in normal eyes respectively. In group A, there was a significant difference in peripapillary RNFL thickness between amblyopic and normal eyes (P=0.0003, 0.04). However, the RNFLestimated integral of both groups after correction of refractive error and axial length showed no significant difference (P=0.34, 0.45). CONCLUSIONS: There was no significant relationship between OCT parameters and final visual acuity after occlusion therapy in hyperopic anisometropic amblyopia.

The Clinical Study of Lacrimal Sump Syndrome after Endonasal Dacryocystorhinostomy

PURPOSE: To investigate the incidence and importance of diagnosis of lacrimal sump syndrome after endonasal dacryocystorhinostomy (DCR). METHODS: A retrospective analysis was performed on 837 eyes in 732 patients, (male 196, female 536) who had undergone endonasal DCR between January 2001 and June 2004. Dacryocystography (DCG) was performed in those patients who had recurrent epiphora or symptoms of dacryocystitis without saline regurgitation on syringing. RESULTS: Among the 90 eyes (10.8%) who had recurrent epiphora after endonasal DCR, 8 eyes were diagnosed with lacrimal sump syndrome and this comprised 8.9% of the causes of DCR failure. CONCLUSIONS: Lacrimal sump syndrome should be considered in the case of patients with recurrent epiphora. However, normal syringing finding after endonasal DCR, and revision may relieve the patients's symptom.

The Clinical Features of Korean Patients with Duane's Retraction Syndrome

PURPOSE: To describe the clinical features of Duane's retraction syndrome (DRS) in Korean patients. METHODS: We retrospectively analyzed the 78 DRS cases that presented to our department between 1995 and 2004. The clinical features investigated included sex distribution, laterality, type of presentation, deviation in primary position, anomalous vertical movements, face turn, amblyopia and anisometropia. RESULTS: There were 38 (48.7%) affected males and 40 (51.3%) females. Left eye predominance (83.3%) was observed, as was type I presentation (85.9%). Orthotropia was found to be the most common primary position in 46 cases (59.0%). Face turn in unilateral DRS was noted in 13 patients (17.1%). There were 6 cases (7.7%) with anisometropia and 4 (5.1%) with amblyopia. CONCLUSIONS: The clinical manifestations of DRS in our study were different from those of equivalent Caucasian studies yet similar to those previously reported for Asian groups. Racial and regional differences were noted, for which further research is needed to elaborate the reasons and mechanisms.

Clinical Factors of Glaucomatous Change in Patients with Posner-Schlossman Syndrome

PURPOSE: To determine the factors that affect glaucomatous change and the clinical course of patients with Posner-Schlossman syndrome. METHODS: A retrospective analysis of 52 eyes of 51 patients who had been diagnosed with Posner-Schossman syndrome between January 1995 and June 2003 was performed. We analysed the factors by the age of onset, the duration of disease, the number of attacks, the highest intraocular pressure, the cup/disc ratio of affected eye and unaffected fellow eye during attacks, and visual field change. RESULTS: Twelve (23.1%) of 52 eyes revealed significant glaucomatous change. The number of attacks showed statistically significant difference between the two groups who had developed glaucoma and who had not (P=0.021). But the age of onset, the duration of disease, and the highest intraocular pressure during attack did not show statistically significant difference (P>0.1). CONCLUSIONS: From this study, we observed that the only factor influencing glaucomatous change in patients with Posner-Schlossman syndrome was the number of attacks. So in case of recurrent attacks, close observation and aggressive treatment is mandatory.

Thicknesses of Macular Retinal Layer and Peripapillary Retinal Nerve Fiber Layer in Patients with Hyperopic Anisometropic Amblyopia

This prospective study was performed to measure the macular and the peripapillary retinal nerve fiber layer (RNFL) thicknesses using optical coherence tomography (OCT) in patients with anisometropic amblyopia. Thirty-one patients with hyperopic anisometropic amblyopia were included. The macular retinal thickness and the peripapillary RNFL thickness were measured using OCT. The mean refractive error was +3.71 diopters (D) and +1.00 D, the mean macular retinal thickness was 252.5 micrometer and 249.7 micrometer, and the mean RNFL thickness was 115.2 micrometer and 109.6 micrometer, in the amblyopic eye and the normal eye, respectively. OCT assessment of RNFL thickness revealed a significantly thicker RNFL in hyperopic anisometropic amblyopia (P=0.019), but no statistically significant difference was found in macular retinal thickness (P> 0.05). In conclusion, the amblyopic process may involve the peripapillary RNFL, but not the macula. However, further evaluation is needed.

Cervicothoracic Extradural Ganglionneuroblastoma Invaded from Mediastinum

Ganglionneuroblastoma is a rare neoplasm involving central nervous system. We have recently experienced a case of cervicothoracic extradural ganglionneuroblastoma invaded from upper posterior mediastinum. The patient presented with a progressive weakness of both lower extremities and had difficulty in voiding. The plain X-ray films, thoracic spine CT scan and myelography disclosed an extradural mass from C6 to T4 level. This extradural mass was communicated with upper posterior mediastinum. The mass was surgically removed and then the patient showed good recovery postoperatively.

Clinical Analysis or Primary Reconstruction to Compound Depressed Frontal Skull Fracture

The injured skull bone may be contaminated in compound frontal skull fracture, so definitely left out for the prevention of infectious complications in the classic concept. The efficacy of primary replacement and resection of the injured bony fragments in the treatment of compound depressed frontal skull fractures was studied in 33 patients who could be followed up over one year during a recent 5-year period. The patients was divided into a group I which took a primary replacement of injured bony fragments and group II which left out the injured bony fragments in immediate operation. The results are summarized as follows : 1) The age incidence was more frequent in the 3th and 4th decades. The sex distribution was more frequent in male(87%). 2) The motor vehicle accident was most frequent in the injury mechanism. 3) The conscious level on admission was 53% in 13~15 GCS group, 12% in 9~12 group, 26.6% in 6~8 group and 8.4% in 3~5 group. 4) The incidence of an extending fractures was 42% to orbital roof, 35% into frontal sinus, 25% into cribriform plate and 16% into nasal bone. 5) The incidence of intracranial injury was 65% in dural laceration and 51% in cerebral laceration. Of cases of dural laceration the cerebral laceration was associated in 78%. 6) The time duration from injury to operation was under 12 hours in most cases(84%). 7) The incidence of a complication was 36.1% in total group, 27.7% in group I and 47.2% in group II. The infectious complication was not a significant difference between group I(14.9%) and group II(16.7%). In conclusion the infectious morbidity of which were most dangerous complications due to compound depressed frontal skull fractures was not a significant difference in two compared group. The author believe that immediate bone replacement for compound depressed frontal fractures with or without extension to frontal sinus, orbit, or cribriform plate os both practical and safe procesures.