Tono pen avia

Within 1 hour before LP, high resolution infrared scanning laser ophthalmoscopy (SLO) images (1536 × 1536 pixels covering a retinal area of 30° × 30°, centered on the optic nerve head were obtained (Spectralis; Heidelberg Engineering, Heidelberg, Germany) in both eyes of each subject. In a single eye of four subjects, three images were obtained during the same imaging session to assess variability. IOP and blood pressure were recorded using Tono-Pen Avia (Reichert Technologies, Ametek, Inc., Buffalo, NY) and automated cuff (BP785, Omran Healthcare, Inc., Omran Corporation, Kyoto, Japan). Mean arterial pressure (MAP) was calculated based on systolic and diastolic values. Near visual acuity of each eye was measured using the subject's own glasses, pinhole occluder, and Rosenbaum pocket vision screener. LP position was recorded. During the LP, opening pressure was recorded as the maximum height of the CSF column above the spinal column (in cm) before collection of CSF. ICP lowering was accomplished by CSF removal during the LP. Within 1 hour after LP high resolution SLO images were obtained in the same manner as those obtained before LP.

Cadaveric human tissue was sourced from the local eye bank for evaluation and validation of the TEMPO model. In order for TEMPO (or any suction-based system) to provide good fixation and effective simulation of the contours and pressure of the in vivo eye using cadaveric material, saline must be injected into the eye, as they are hypotonous on delivery from the eye bank. Thus, 3–4 mL of saline was injected into the posterior compartment using a 30-gauge needle through the optic nerve head and the eye centred on the cylindrical flange; suction was drawn using the 50 mL syringe, and the overlying orbital rim housing placed prior to evaluation (see Youtube video link below for demonstration). The ability of the model to establish and maintain IOP was assessed using a handheld tonometer (Tonopen Avia, Reichert Technologies, New York, USA). Local surgical residents practised procedures including corneal and scleral suturing and construction of clear corneal incisions and were asked to compare the TEMPO model to other mount systems. The ease with which the model could be disassembled and sanitised was also assessed. A similar battery of tests was performed with the polymer simulation eye. Use of the TEMPO model, including assembly, suturing, and disassembly can be viewed in our YouTube video: (Link) https://www.youtube.com/watch?v=MWdjJjzAk8w.

We investigated the intraocular biocompatibility and ocular irritation of Dex-SA-FFFE nanoparticles in healthy Japanese big-eared white rabbits after topical instillation. Japanese big-eared white rabbits (weight: 2.0–2.5 kg) were provided by Wenzhou Medical University Laboratory Animal Center (Wenzhou, China). All animal experiments were conducted with the Guidelines for Care and Use of Research Animals established by Wenzhou Medical University and approved by the Ethical Committee of Wenzhou Medical University. Prior the in vivo applications, the formed Dex-SA-FFFE nanoparticles were sterilized by 0.22 µm filter membrane. The right eyes of the rabbits were topically instilled with 50 µL of Dex-SA-FFFE nanoparticles (30 mg/mL Dex-SA-FFFE) four times daily (6 mg Dex-SA-FFFE per eye daily) for three successive days, while the left eyes were topically instilled with 50 µL of PBS (pH =7.4). Clinical signs including conjunctival hyperemia, corneal edema, and lens opacity were monitored daily by a slit-lamp (SLM-4ER; Chongqing Kanghua Ruiming S&T Co., Ltd., Chongqing, China). The integrity of the corneal epithelium was checked by a fluorescein staining assay. Meanwhile, changes in intraocular pressure and corneal thickness were measured by a handheld tonometer (Tono-Pen AVIA^®, Reichert Technologies, Depew, NY, USA) and an iVue (Optovue, Fremont, CA, USA), respectively.

The study was conducted on 75 participants between January 1, 2013, and April 30, 2013. A pretested structured questionnaire was used to obtain demographic data and the clinical history or each patient. The ophthalmological examination, conducted by the primary investigator (C.O.), included a best corrected visual acuity evaluation, slit lamp, and IOP measurement using both the Tono-Pen AVIA (Reichert Technologies) and GAT. The Tono-Pen was calibrated weekly and the GAT was calibrated monthly by our biomedical technician. The GAT was used first and then, after 10 min (to allow recovery of the cornea), the Tono-Pen measurement was performed. All the measurements were made by the same examiner (C.O.) and in all patients the IOP measurements were made during the same period of the day (i.e. between 09.00 and 12.00 h). Two readings were taken with each instrument and the average of each was recorded. After the measurements the subject was asked which of the instruments they found more acceptable. The CCT was measured with an ultrasonic pachymeter (OcuScan RxP; Alcon Laboratories, Fort Worth, Tex., USA). Visual field defects were assessed using a visual field perimeter (Humphrey Matrix FDT; Carl Zeiss Meditec AG, Jena, Germany). Gonioscopy and slit lamp biomicroscopy of the fundus after papillary dilatation were performed subsequently.

IOP was measured and recorded in each eye separately by an ophthalmologist blinded to the groups using applanation tonometry (Tono-Pen Avia, Reichert Technologies). To prevent infection spread, the tip of the tonometer was covered with a separate cover (Ocu-Film Tip Covers) for each patient before taking the measurements. IOP was measured and recorded a total of 5 times; preoperatively, at 2 min after drug administration, and at 1, 5, and 10 min after intubation.