We conducted an investigation of the relation between RNFL thickness and optic disc size along with an interocular comparison of optic disc size, RNFL thickness, and RNFL density in healthy subjects. A total of 64 normal eyes from 32 Korean volunteers were enrolled in this study. A GDx Nerve Fiber Analyzer with software version 2.0.09 was used to image all subjects. Optic disc size was measured by pi x (horizontal radius) x (vertical radius). The RNFL density of each quadrant was calculated by dividing each quadrant integral by the total integral. Optic disc size was positively correlated with the total RNFL thickness (r = 0.615, p < 0.01). Optic disc size and RNFL density were inversely related in the superior quadrant (r = -0.248, p < 0.05). There was a significant positive correlation between optic disc size and RNFL density in the nasal quadrant (r = 0.439, p < 0.01) and the temporal quadrant to a certain degree. A significant positive correlation was found between the right and left eyes in terms of total RNFL thickness in and that of each quadrant. Interocular RNFL density was positively correlated in both the temporal and nasal quadrants. These findings must be considered when one evaluates and compares RNFL measurements between two eyes as is often the case where both eyes are usually affected in the course of glaucomatous RNFL damage.
Adult ; Comparative Study ; Female ; Human ; Lasers/diagnostic use ; Male ; *Nerve Fibers ; Optic Disk/*anatomy & histology ; Optic Nerve/*anatomy & histology ; Perimetry ; Weights and Measures

OBJECTIVE: To investigate the anatomical relationship among optic nerve, posterior ethmoid sinus and ophthalmic artery to further provide surgical instruction for endoscopic transsphenoidal optic nerve decompression. METHOD: Messerklinger technique was adopted in eight cases of adult cadaveric head to expose the posterior ethmoid sinus and sphenoid sinus. The optic-carotid recess and optic canal were identified. The adjacent structure of optic canal was observed. After removal of the bony wall of optic canal, the relationship between the optic nerve and the ophthalmic artery was disrupted. RESULT: the optic-carotid recess was observed in all specimens. The occurrence of optic nerve prominence was 62%. Three patterns of the syntropy of optic nerve were observed. Optic nerve was border by posterior ethmoid sinus anteriorly and sphenoid sinus posteriorly in 8 cases (50%), by sphenoid sinus in 5 (31%), and by posterior ethmoid sinus in 3 (19%). At the cranial end, The ophthalmic artery was observed, 9 (56%) inferior-medially, 4 (25%) inferiorly and 3 (19%) inferior-laterally relative to optic nerve. At the ophthalmic end, the artery was observed 3 (19%) inferiorly and 13 (81%) inferior-laterally relative to optic nerve. CONCLUSION The optic-carotid recess can be regarded as the first landmark. The ophthalmic artery injury should be avoided with regard to its relationship with optic nerve during endoscopic decompression surgery.
Adult ; Cavernous Sinus ; anatomy & histology ; Decompression, Surgical ; methods ; Endoscopy ; Ethmoid Sinus ; anatomy & histology ; Humans ; Ophthalmic Artery ; anatomy & histology ; Optic Nerve ; anatomy & histology ; surgery ; Orbit ; anatomy & histology ; Sphenoid Sinus ; anatomy & histology ; surgery

OBJECTIVE: To provide transnasal endoscopic optic canal decompression with the anatomic reference. METHOD: 15 samples of the adult corpse wet specimen (30 sides for the optic canal) were examined under the endoscope to scrutinize the regional anatomy of the optic canal. RESULT: distance between the spina nasalis anterior and the midpoint of optic canal medial wall is (61.02 +/- 5.83) mm, and the angle between spina nasalis anterior and the midpoint of optic canal medial wall is (45.1 +/- 4.81) degrees. The medial wall of optic canal is longest, with an average length of (11.61 +/- 1.58) mm; the lateral wall of optic canal is thickest, and the medial wall thinnest. 10 traumatic blind patient underwent endoscopic optic canal decompression with satisfactory outcome. CONCLUSION The regional anatomy of the optic canal under endoscope is of importance to endoscopic optic canal decompression. Which is microinvasive with direct approach and clear view thus is widely used in clinical practice.
Adolescent ; Adult ; Blindness ; surgery ; Child ; Endoscopy ; Female ; Humans ; Male ; Middle Aged ; Nose ; anatomy & histology ; surgery ; Optic Nerve ; anatomy & histology ; surgery ; Orbit ; anatomy & histology ; surgery ; Young Adult

BACKGROUNDWith conventional imaging methods only the morphous of the visual nerve fiber bundles can be demonstrated, while the earlier period functional changes can not be demonstrated. We hypothesized that diffusion tensor imaging (DTI) would demonstrated the whole optic never fiber bundle and visual pathway and the earlier period functional changes. The purpose of the present study was to evaluate the application of DTI technique in the demonstration of the whole optic never fiber bundle and visual pathway, and the influence of orbital tumors on them.

METHODSGE 1.5 T signa HD MR System, and the software package DTV2 were adopted. The total 45 subjects were enrolled, including 15 volunteers and 30 patients. All patients had ocular proptosis from minor to major. Seven patients had visual acuity decrescence.

RESULTSThe nerve fiber bundles, e.g. optic chiasma, optic tract and optic radiation in posterior visual pathway were well demonstrated in all cases. Wherein, the intact whole visual pathway fiber bundles were clearly revealed in 10 volunteers and 17 patients, and optic nerve was not wholly revealed in the rest of the subjects. Shift of optic nerve caused by compression and partial deformation were seen in 7 patients with orbital tumor. In 6 of 7 patients, DTI displayed significant abscise and deformation of visual nerve. Chi-square test indicated significant correlation between visual acuity decrescence and DTI visual nerve non-display.

CONCLUSIONSVisual nerve fiber bundles and the whole visual pathway were visualized in most of patients with DTI. It might be an effective method of providing imaging evidence for visual nerve fiber earlier period functional changes, and laid a foundation for the study in other cranial nerves.

Adult ; Aged ; Diffusion Magnetic Resonance Imaging ; methods ; Exophthalmos ; pathology ; Female ; Humans ; Male ; Middle Aged ; Optic Chiasm ; anatomy & histology ; pathology ; Optic Nerve ; anatomy & histology ; pathology ; Visual Pathways ; anatomy & histology ; pathology ; Young Adult

OBJECTIVE: To investigate the accuracy and clinical application of multi-slice spiral CT imaging on optic canal area. METHOD: Forty intact specimens of human corpse head were tested with three dimensional reconstruction of multi-slice spiral CT imaging. The results of radiology and anatomy were compared on adjacent structures of optic canal interior wall and its developmental relationship with sphenoid sinus. RESULT: (1) The high spatial resolution of integrity could be obtained with dimensional processing technique. The anatomical structure of optic canal and its surrounding area could be demonstrated clearly. (2) With the technique of virtual endoscopy, the interior reconstruction of optic canal could demonstrate the inner topography of optic canal, the reconstruction image of which was identical to that of the control subjects. (3) There was no significant difference between the data of multi-slice spiral CT imaging and that of anatomy (P > 0.05). CONCLUSION Associated application of dimensional processing technique and virtual endoscopy, not only can the subtle structures of optic canal be demonstrated and measured, but also the detailed information on spatial relationships of optic canal area can be provided for operation.
Adult ; Asian Continental Ancestry Group ; Female ; Humans ; Imaging, Three-Dimensional ; Male ; Optic Nerve ; anatomy & histology ; diagnostic imaging ; Tomography, Spiral Computed

OBJECTIVETo study the fractional anisotropy (FA) and the architecture of the optic radiation fiber tracts of normal adults with magnetic resonance (MR) diffusion tensor imaging (DTI).

METHODSDiffusion tensor images were obtained from 30 healthy volunteers without any cerebral abnormalities on conventional MRI. FA and the mean diffusivity (MD) of the optic radiation were measured in the directional encoded color (DEC) maps. The architecture of the optic radiation fiber tracts were displayed with the software of diffusion tensor fiber tracking.

RESULTSIn all subjects, the optic radiation could be readily identified in the DEC maps. The FA value was 0.509-/+0.029 in the left and 0.502-/+0.026 in the right, with the MD value of (0.763-/+0.050) x10(-3) and 0.748-/+0.052)x10(-3) mm2/s, respectively. No significant differences were found in the FA or MD value of the bilateral optic radiation (P>0.05). Diffusion tensor tractography (DTT) demonstrated that the 3 bundles of the optic radiation fibers were located in the lateral sagittal stratum, passing from the lateral geniculate body of the thalamus to the primary visual cortex. The dorsal and lateral bundles passed posteriorly to the superior bank of the calcarine cortex, while the ventral bundle passed anteriorly before making a sharp turn, known as the Meyer loop, and subsequently coursed posteriorly to terminate in the inferior margin of the calcarine cortex, which was consistent with the results of classic anatomical studies.

CONCLUSIONAs a novel method to study the relationship between visual function and optic pathway, DTI and DTT can show the FA and architecture of the optic radiation.

Adult ; Anisotropy ; Diffusion Magnetic Resonance Imaging ; methods ; Echo-Planar Imaging ; methods ; Female ; Geniculate Bodies ; anatomy & histology ; Humans ; Male ; Middle Aged ; Models, Anatomic ; Occipital Lobe ; anatomy & histology ; Optic Nerve ; anatomy & histology ; Visual Pathways ; anatomy & histology ; Young Adult

This study was carried out to assess the feasibility of ultrasonographic measurements of the optic nerve sheath diameter (ONSD) in normal dogs and evaluate the effect of breed, sex, body weight and age on biometry of ONSD. The ONSDs were evaluated in 15 dogs (10-50 months old)with normal eye (7 Yorkshire terrier and 8 Maltese). Ultrasonographic measurements of the ONSD were carried out at a constant position located 5 mm behind the optic disc. Eyes were collected immediately after euthanasia, and were used for saline immersion technique and direct measurement by calipers for biometry of ONSD. In this study, there was no significant difference of ONSD between the left and the right eyes, and was no significant difference among ONSD values obtained from ultrasonographical method, saline immersion technique and direct measurement (k = 0.95). Also, there was no correlations between ONSD and sex, body weight and age, but was significant between the mean ONSD of Yorkshire terrier and Maltese (p<0.01). The mean ONSD of Yorkshire terrier was 2.10 +/- 0.22 mm and Maltese was 1.63 +/- 0.23 mm. This study suggests that ultrasonographic measurements is useful method for biometry of the ONSD in normal dogs and provides baseline information for the study of evaluating ONSD in various breeds and diagnosing several diseases with the change of the ONSD.
Age Factors ; Animals ; Biometry/methods ; Dogs/*anatomy & histology ; Female ; Linear Models ; Male ; Myelin Sheath/ultrasonography ; Optic Nerve/*ultrasonography ; Reproducibility of Results ; Sex Factors

BACKGROUNDRTVue spectral-domain optical coherence tomography (OCT) is a new, ultra high-speed and high-resolution instrument, potentially to measure the presence of glaucoma or its progression accurately. The objective of this study was to evaluate its reproducibility of retinal nerve fiber layer (RNFL) thickness and optic nerve head (ONH) measurements in normal and glaucoma eyes.

METHODSThis study was an observational clinical study. One eye was selected randomly from each of 89 normal individuals and 63 glaucoma patients in a range of severity. RNFL thickness and ONH were measured 3 times on the same day to determine intrasession variability. The same instrument was used by the same operator for all scans. Intrasession within-subject standard deviation (Sw), precision (1.96 x Sw), coefficient of variation (CVw, 100 x Sw/overall mean), and intraclass coefficient (ICC) were calculated to evaluate reproducibility.

RESULTSRTVue OCT demonstrated double hump patterns in the RNFL profiles. High reproducibility was observed in all ONH parameters. For normal eyes, the value of ICC ranged between 0.98 and 1.00. For eyes with different extent of glaucoma, it ranged between 0.94 and 1.00. High reproducibility was also observed in RNFL thickness measurements. The values of ICC for averaged RNFL thickness ranged between 0.95 and 1.00 in all cases. For regional parameters, it ranged from 0.94 to 0.98 for normal eyes, 0.94 to 1.00 for mild glaucoma eyes, 0.87 to 1.00 for moderate glaucoma eyes, and 0.77 to 0.97 for severe glaucoma eyes. The nasal regions of severe glaucoma appeared to be most variable, as nasal lower region and inferior nasal region had the ICC values of 0.77 and 0.87.

CONCLUSIONReproducibility of RTVue RNFL and ONH measurements was excellent in normal and glaucoma groups.

Adult ; Aged ; Cross-Sectional Studies ; Female ; Glaucoma ; pathology ; Humans ; Male ; Middle Aged ; Nerve Fibers ; Optic Disk ; anatomy & histology ; pathology ; Tomography, Optical Coherence ; methods ; Young Adult

Purpose: To determine the proportion of glaucoma suspects with abnormal nerve fiber layer measurement using GDx nerve fiber analyzer Methodology: The study population consisted of glaucoma suspects between ages 30-70 years, who underwent glaucoma workup including retinal nerve fiber layer measurement (GDx NFA) Results: 35 eyes of glaucoma suspects were analyzed. 28/35 were found to have normal NFL thickness; 5/35 have 1 abnormal GDx parameters; 1/35 with 3 abnormal GDx parameters; 1/35 with 3 GDx abnormal parameters. Linear regression analysis showed no correlation between C:D and GDx parameters Conclusion: This study confirms that superior maximum is useful to the other parameters but there is a need to collect more samples. (Author)
Human ; Male ; Female ; Aged ; Middle Aged ; Adult ; RETINA/ANATOMY & HISTOLOGY ; NERVE FIBERS ; GLAUCOMA ; HUMAN ; OPTIC DISK ; SCANNING LASER POLARIMETRY ; LASER/DIAGNOSTIC USE

PURPOSE: To assess the impact of axial length on the age-related peripapillary retinal nerve fiber layer (RNFL) thinning. METHODS: This cross-sectional observational comparative case series included 172 eyes from 172 healthy Korean subjects. Peripapillary RNFL thickness was measured using an Optic Disc Cube 200 x 200 scan of spectral domain Cirrus HD OCT and the axial length was measured using IOL Master Advanced Technology. In age groups based on decade, the normal ranges of peripapillary RNFL thickness for average, quadrant, and clock-hour sectors were determined with 95% confidence intervals. After dividing the eyes into two groups according to axial length (cut-off, 24.50 mm), the degrees of age-related RNFL thinning were compared. RESULTS: Among the eyes included in the study, 53 (30.81%) were considered to be long eyes (axial length, 25.04 +/- 0.48 microm) and 119 (69.19%) were short-to-normal length eyes (axial length, 23.57 +/- 0.60 microm). The decrease in average RNFL thickness with age was less in long eyes (negative slope, -0.12 microm/yr) than in short-to-normal length eyes (negative slope, -0.32 microm/yr) (p < 0.001). CONCLUSIONS: Age-related thinning of peripapillary RNFL thickness is attenuated in long eyes compared to short-to-normal length eyes.
Adult ; Aged ; Cross-Sectional Studies ; Eye/*anatomy & histology ; Female ; Humans ; Macular Degeneration/*epidemiology/pathology ; Male ; Middle Aged ; Nerve Fibers/*pathology ; Optic Disk/*pathology ; Prevalence ; Republic of Korea/epidemiology ; Retinal Ganglion Cells/*pathology ; Severity of Illness Index ; *Tomography, Optical Coherence