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specular method. Acta

**19**

**Chapter 2**

**Abstract**

**1. Introduction**

surgeries.

**2. Intraoperative OCT**

Tomography

*Samet Gulkas and Osman Cekic*

with its feasibility, surgical impacts, and limitations.

anterior segment *i*OCT, posterior segment *i*OCT

Intraoperative Optical Coherence

Recently, surgical instruments and imaging technology in ophthalmology have shown a great improvement. However, advances in the field of the operating microscope technology still remained unchanged with the various limitations for the surgeons. Invention of optical coherence tomography (OCT) led to a revolution in the diagnosis and monitoring of numerous anterior and posterior segment pathologies. Recently, OCT has been introduced into the operating room with an impact on the surgeons. In this chapter, we review the evolution of OCT for intraoperative use

**Keywords:** intraoperative optical coherence tomography, microscope-integrated,

Optical coherence tomography (OCT) is a rapid, noninvasive, noncontact, and cross-sectional imaging method that produces images of ocular tissues. OCT uses reflected light to obtain the images from the different layers on the ocular tissues that produce different backscattered lights [1]. After using of spectral-domain OCT (SD-OCT) instead of time-domain OCT (TD-OCT), the images produced by OCT have become with higher resolution; thus, OCT has begun to provide more detailed information on ophthalmologic diagnoses [2]. Recent developments in ocular imaging technology have made the OCT a vital diagnostic tool in patient care. More recently, the availability of OCT during surgery has begun to be discussed. The introduction of OCT into the operating room (OR) called as intraoperative OCT (*i*OCT) has provided new insights into the surgical management during ophthalmic

A number of researchers have examined the potential role of *i*OCT in various conditions and procedures, such as macular hole (MH), epiretinal membrane (ERM), retinal detachment surgery, and lamellar keratoplasty [3–6]. However, conventional clinical OCT devices are large and not portable; therefore, it would be difficult and impractical to transfer the conventional OCTs into OR. In addition, the supine position of the patient during a surgery and changes to surgical flow are other potential obstacles for image acquisition with good quality. All these hurdles forced researchers to produce a portable OCT device. Initial attempts with

### **Chapter 2**
