View clinical trials related to Optic Nerve Sheath.
Filter by:Today, phacoemulsification has become the most commonly applied method in the treatment of cataract, which is considered as a public health problem. Since the eyelid margins can be a source for pathogens in phacoemulsification surgery draping after skin sterilization is applied to remove the eyelashes from the operation area. Since surgical drapes are airtight, carbon dioxide (CO2) accumulation occurs under the drape in patients under local anesthesia. During the operation, if the end tidal CO2 pressure value rises, this can lead to hyperventilation and tachycardia and also increase the intraocular pressure which is undesirable in eye surgery. In our study, in order to observe and compare undesirable conditions, regional tissue oxygenation saturation (rSO2) will be determined non-invasively with Transcutaneous Near Infrared Spectroscopy (NIRS) technology , which allows real-time monitoring. Changes in the partial pressure of carbon dioxide (PaCO2) are strongly vaso-active, resulting in changes in cerebral blood volume and hence intracranial pressure. As the optic nerve sheath is an extension of the brain dura mater, the diameter of the sheath expands in case of increased intracranial pressure. Evaluation of the optic nerve sheath with ultrasound allows us to obtain information about intracranial pressure. For optic nerve sheath diameter, measurements above 5.0 mm in adult patients are generally considered as increased intracranial pressure. COVID-19 is a global epidemic caused by SARS-CoV-2 that we are still fighting. Although it is a multisystemic disease, it is important in terms of its effects on pulmonary function and the continuity of pulmonary symptoms and findings after this disease has been overcome. In our study, End-Tidal CO2 and cerebral oximetry (NIRS) values will be determined and compared between the groups that received 2lt/min and 4lt/min nasal oxygen support during cataract surgery performed using draping under local anesthesia in patients who had COVID-19, recovered and never had. It was aimed to evaluate and compare the values of optic nerve sheath diameter increase.
Elevated intracranial pressure (ICP) is one of the most common symptoms encountered in a variety of traumatic injuries and diseases. Any tissue swelling within the rigid confines of the skull results in increased ICP, which may lead to life-threatening structural alterations in the brain or cerebral blood flow, thus causing oxygen deprivation and ischemia in the brain. Methods for ICP monitoring can be divided into invasive and noninvasive approaches. In fluid-based systems, external ventricular drainage (EVD) has been considered the gold standard. Clinicians have found several noninvasive methods that can be used as surrogates for invasive methods for ICP measurement. The optic nerve, as part of the central nervous system, is wrapped by the dural sheath. The optic nerve sheath (ONS) is the continuation of the subarachnoid space at the optic nerve, and its tissues are connected with the subarachnoid space. Thus, an increase in ICP results in a corresponding elevation of the ONS diameter (ONSD). Hypertonic solutions such as mannitol and hypertonic saline (HTS) are recommended early in the management of ICH after severe TBI . They provide therapeutic benefit along with a wide therapeutic margin. The most recent BTF guidelines stated "although hyperosmolar therapy may lower intracranial pressure, there was insufficient evidence about effects on clinical outcomes to support a specific recommendation, or to support use of any specific hyperosmolar agent".
The pneumoperitoneum during laparoscopic surgery have the potential to cause an increase of intracranial pressure (ICP). Previous studies have proposed that ultrasonographic measurements of the optic nerve sheath diameter (ONSD) correlate with signs of increased ICP. The aim of this study is to compare the effect of pnemoperitoneum on intracranial pressure and cerebral oxygenation during laparoscopic surgery according to anesthesia agents, propofol based total intravenous anesthesia (TIVA group) and desflurane anesthesia (Des group).