The efficacy of drug delivery to the posterior segment by systemic, local or topical routes is hindered by the blood-retinal barrier, tight intercellular junctions and scantly vascularized spaces. Although intravitreal injection has proved effective for delivery of therapeutic agents into the vitreous cavity and retina, it is impractical for frequent or sustained dosing. Intravitreal sustained ...

BACKGROUND Anterior lumbar disc replacements are used to restore spinal alignment and kinematics of a degenerated segment. Compared to fusion of the segment, disc replacements may prevent adjacent segment degeneration. To resolve some of the deficiencies of anterior lumbar arthroplasty, such as the approach itself, difficulty of revision, and postoperative facet pain, 360° motion preservation s...

The case of a 40-year-old-man who presented to our clinic with bilateral blindness as a consequence of bomb blast injuries is reported. He had a completely opaque cornea, partially damaged posterior segment and perception of light in the right eye, while a clear cornea, totally damaged posterior segment and no light perception in the fellow eye. His corneas were successfully swapped which gave ...

Foreign bodies may drop during removal from the posterior segment and result in foveal damage. Due to high specific gravity and viscosity, ophthalmic viscosurgical devices (OVDs) can dampen and redirect the force of the dropping foreign body and therefore protect the fovea. Herein we describe our technique of foveal protection with OVDs and briefly demonstrate the results in five eyes with larg...

A retrospective study of intraocular foreign bodies treated at the University Hospital over 10 years from 1970 1979 was carried out. Of the 48 cases reviewed, nine were anterior chamber foreign bodies while the rest were posterior segment foreign bodies. The anterior chamber foreign bodies had better visual prognosis as compared to the posterior segment foreign bodies. Most of the patients were...

abstract   background: to evaluate proximal junctional segment changes in adolescent idiopathic scoliosis(ais) the posterior spinal fusion and also instrumentation also and finding of probable risk factors, were all considered in this study.   methods: we retrospectively reviewed radiographs of 121 consecutive patients who underwent posterior spinal fusion for ais from t3 or below, with a mean ...

To investigate the effect of PLIF and after rigid fixation on adjacent segment and subjacent mechanical instability moreover under loading adjacent and subjacent segment mechanical behavior. Eleven fresh-frozen lamb lumbar spines (Sacrum-T12) were loaded, in axial, flexion-extension, right-left bending directions. All specimens were tested intact and after implantation with posterior pedicle sc...

Treatment of unstable thoracolumbar burst fractures remains controversial. Long-segment pedicle screw constructs may be stiffer and impart greater forces on adjacent segments compared with short-segment constructs, which may affect clinical performance and long-term out come. The purpose of this study was to biomechanically evaluate long-segment posterior pedicle screw fixation (LSPF) vs short-...

A rotary motor in a termite flagellate continually turns the anterior part of the cell (head) in a clockwise direction. Previous descriptive observations implicated the noncontractile axostyle, which runs through the cell like a drive shaft, in the motile mechanism. This study demonstrates directly that the axostyle complex generates torque, and describes serval of its dynamic properties. By la...