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The Special Sense Organs and Their Disorders
Published in Walter F. Stanaszek, Mary J. Stanaszek, Robert J. Holt, Steven Strauss, Understanding Medical Terms, 2020
Walter F. Stanaszek, Mary J. Stanaszek, Robert J. Holt, Steven Strauss
Gonioscopy is the examination of the angle of the anterior chamber with a gonioscope (lens) or a contact prism lens and beam illumination from a slit lamp. This procedure is used to detect retinal or optic nerve disease. Applanation tonometry is used to measure intraocular pressure in millimeters of mercury (mmHg). If diagnosis is still in doubt, provocative procedures such as a water drinking test, darkroom test, or mydriatic tests are employed. Other diagnostic procedures may include gross visual fields and basic motor exam, fluorescent angioscopy (examination of the capillary vessels), slit lamp examination, keratometry, ophthalmodynamometry, needle oculo-electromyography, electro-oculography (EOG), and retinoscopy.
Surgical repair of primary deep vein valve incompetence
Published in Peter Gloviczki, Michael C. Dalsing, Bo Eklöf, Fedor Lurie, Thomas W. Wakefield, Monika L. Gloviczki, Handbook of Venous and Lymphatic Disorders, 2017
First described by Gloviczki et al.34 from the Mayo Clinic, this technique has gained many adherents.33–35 It is an enhancement of the external repair technique; transluminal instead of transmural sutures are used along the valve attachment lines. By visualizing the valve apparatus with an angioscope introduced through a small venotomy above the valve station, the transluminal sutures not only appose the valve attachment lines, but also tighten the valve cusps. Angioscopic irrigation is required for proper visualization of the valve apparatus; a watertight purse string suture around the venotomy is required. Some extravasation of the irrigant into the vein wall at the venotomy site is common and minor intimal trauma from manipulation of the tip of the angioscope is unavoidable. It is actually quite difficult to direct the sutures under angioscopic visualization to catch the valve cusps. More often, angioscopic inspection merely confirms that the sutures have traversed the valve after they had been placed. It appears that transluminal sutures placed along the valve attachment lines usually tack or tether the redundant valve cusps; the angioscope is confirmatory, but not an aid in the actual placement of sutures. This insight led to the development of transcommissural valvuloplasty described above.
Complications of Open Arterial Vascular Surgery
Published in Stephen M. Cohn, Matthew O. Dolich, Complications in Surgery and Trauma, 2014
When a saphenous vein conduit has been used, and the bypass clots acutely in the perioperative period, one has to consider possible defects within the graft as a potential cause. The possible defects will vary depending on what technique was used. A reversed vein graft may have a sclerotic or relatively narrower segment that may have not been noticed at initial surgery. For in situ bypasses, the possibilities of a retained valve or perivalvular damage from the valvulotome must be considered. Detection of such abnormalities may require visualization of the entire graft after thrombectomy. Angiography may not be the best technique for the detection of certain abnormalities. Intraoperative duplex may be advantageous as would angioscopy, although few are adept with this technique. If a clear cause in the graft itself for failure has not been identified and other causes for graft thrombosis (see earlier section) have been ruled out, it may be necessary to replace the conduit entirely. If a defective segment is identified, it will be necessary to replace that one segment.
Decision making in anomalous aortic origin of a coronary artery
Published in Expert Review of Cardiovascular Therapy, 2023
Hitesh Agrawal, Alexandra Lamari-Fisher, Keren Hasbani, Stephanie Philip, Charles D. Fraser, Carlos M. Mery
Echocardiography generally evaluates the origin of the coronary arteries, ventricular function, and wall motion abnormalities. CTA is useful not only as a confirmatory test but as the imaging modality to define all anatomical details that will help with further decision-making (Figure 2). CTA is used to evaluate the exact origin, course, caliber, and branching pattern of coronary arteries. Images are obtained with retrospective electrocardiography gating and are transferred to a post-processing workstation. Image-reformatting techniques and virtual angioscopy are used for analysis. The standard reading and reporting template used (see above, ‘Nomenclature and classification’) is useful not only for communication within the program but also for longitudinal data collection and communication with other providers.
Ticagrelor versus clopidogrel for prevention of subclinical stent thrombosis detected by optical coherence tomography in patients with drug-eluting stent implantation—a multicenter and randomized study
Published in Platelets, 2021
Xiangqi Wu, Wei You, Zhiming Wu, Qiang Wu, Jun Jiang, Hua Yan, Fei Ye, Shaoliang Chen
Stent thrombosis (ST) is the major cause of stent failure after percutaneous coronary intervention (PCI), often (up to 80% of patients with ST) leading to myocardial infarction (MI) or death [1,2]. With the new generation (cobalt chromium, biodegradable polymer) of drug-eluting stents (DES), late occurrence of ST decreased significantly relative to the first-generation DES, varying from 1% to 3% [3–5]. The mechanisms of ST are affected by many factors, including gene polymorphism, residual drugs, antithrombotic therapy, incomplete stent apposition, lesion stability, presence of permanent polymer, and metallic toxicity, etc. [1–5]. However, locally activated inflammation at the site of uncovered metallic struts is thought to be correlated with ST formation [4,5]. Furthermore, intracoronary angioscopy studies reported a large proportion of subclinical silent ST at the site of uncovered stent struts without endothelialization [6,7]. These results were in line with the findings detected by optical coherence tomography (OCT) [8,9]. It has been reported that unnoticed loss of an unexpanded stent was a known infrequent complication of PCI, which leaded to a chronically lost stent as a result of unendothelialization and subclinical ST after 3 years [10]. Mano and his team have shown that subclinical ST observed by coronary angioscopy in a total of 248 second-generation DES in 179 patients at 9 months was independently associated with poor clinical outcome [11]. Totally, these results revealed that how to effectively prevent and treat subclinical ST will become a challenge project.
Histopathologic and physiologic effect of overlapping vs single coronary stents: impact of stent evolution
Published in Expert Review of Medical Devices, 2018
Atsushi Sakamoto, Sho Torii, Hiroyuki Jinnouchi, Renu Virmani, Aloke V. Finn
To date, most preclinical studies in animal models such as those in normal swine and rabbits using the overlapping configuration demonstrated delayed healing at overlapping sites as compared to single stents. In diseased human coronary arteries, pathologic studies comparing patients presenting with acute myocardial infarction (AMI) to those with stable angina treated with first-generation DES have shown delayed vascular healing at culprit sites of AMI as compared to stable angina culprit sites. This was also confirmed using angioscopy in living patients. However, second-generation DES has attenuated this discrepancy, although some differences still remain.