ABSTRACT
To determine the effect of software upgrades on retinal nerve fiber layer [RNFL] thickness measurements taken by spectral domain optical coherence tomography [SD-OCT]. Eighty normal eyes [40 patients] were scanned for RNFL thickness measurements using Spectralis [Heidelberg Engineering, Heidelberg, Germany] SD-OCT. Scan analysis was performed using version 4.0 software and then reanalyzed with version 5.1.3. Student paired t testing and Pearson's correlation coefficient were used for statistical analysis. Average and quadrant RNFL thicknesses generated using version 4.0 and 5.1.3 software on Spectralis demonstrated high correlation [r = 0.955-0.998]. Average RNFL thickness using version 4.0 was 0.08micro m thinner than version 5.1.3 [p = 0.409]. Quadrant RNFL differences ranged from -0.26 to +0.97 microm [p = 0.146-0.915]. Segmentation errors were reduced 33% after the upgrade. Minor RNFL thickness changes may occur after software upgrades in Spectralis OCT. The differences did not reach statistical significance but segmentation errors were improved
ABSTRACT
Anterior chamber drainage angle surgery, namely trabeculotomy and goniotomy, has been commonly utilized in children for many years. Its' reported success has ranged between 68% and 100% in infants and young children with congenital glaucoma. However, the long-term success of these procedures has been limited in adults presumably due to the formation of anterior synechiae [AS] in the postoperative phase. Recently, ab interno trabeculectomy with the Trabectome_ has emerged as a novel surgical approach to effectively and selectively remove and ablate the trabecular meshwork and the inner wall of the Schlemm's canal in an attempt to avoid AS formation or other forms of wound healing with resultant closure of the cleft. This procedure seems to have an appealing safety profile with respect to early hypotony or infection if compared to trabeculectomy or glaucoma drainage device implantation. This might be advantageous in some of the impoverish regions of the Middle East and Africa where patients experience difficulties keeping up with their postoperative visits. It is important to note that no randomized trial comparing the Trabectome to other glaucoma procedures appears to have been published to date. Trabectome surgery is not a panacea, however, and it is associated with early postoperative intraocular pressure spikes that may require additional glaucoma surgery as well as a high incidence of hyphema. Reported results show that postoperative intraocular pressure [IOP] remains, at best, in the mid-teen range making it undesirable in patients with low-target IOP goals. A major advantage of Trabectome surgery is that it does not preclude further glaucoma surgery involving the conjunctiva, such as a trabeculectomy or drainage device implantation. As prospective randomized long-term clinical data become available, we will be better positioned to elucidate the exact role of this technique in the glaucoma surgical armamentarium