Using Ultrasound Biomicroscopy Examination Research Articles

Ultrasound biomicroscopy of sclerotomy sites after conventional and sutureless (23, 25 G) pars plana vitrectomy

Purpose To evaluate postoperative outcomes of transconjunctival sutureless pars plana vitrectomy (PPV), using ultrasound biomicroscopy (UBM), conventional PPV, and transconjunctival sutureless vitrectomy (TSV) sclerotomy sites were compared using UBM. Patients and methods A total of 30 patients underwent complete ophthalmological examination. Conventional PPV was performed following the same surgical techniques, and all TSV procedures were performed by one surgeon. The 20-, 23-, and 25-G vitrectomy systems were used, with 10 patients in each gauge. UBM examination was performed after 1–30 days following surgery to locate and document the sclerotomy sites. Results The 20, 23, and 25 G sclerotomies showed no statistical difference in site diameter at UBM. All patients had at least two diameters of the incision measured, and all wounds were constructed obliquely. The mean size of 20 G sclerotomy was 375.40±83.70 µm (range, 280.4–695 µm) and coefficient of variation was 0.21. The mean size of 23 and 25 G sclerotomy was 315.5±56.8 µm (range, 253.2–362.5 µm; coefficient of variation=0.26; P<0.556). Conclusion Postoperative UBM examination allowed the evaluation of the wound architecture and showed no statistical difference between conventional 20 G and TSV 23, 25 G sclerotomies.

Analysis of bleb morphology after CLASS with ultrasound biomicroscopy and clinical grading scale.

Filtration in the area subjected to CO2 laser-assisted sclerectomy surgery (CLASS) is described using ultrasound biomicroscopy (UBM) and the clinical grading scale to evaluate the mechanism of intraocular pressure (IOP) reduction. Twenty-eight patients with open-angle glaucoma underwent CLASS. The Indiana Bleb Appearance Grading Scale evaluation was performed 1 month after surgery to determine bleb height, extent, vascularity, and leakage. UBM was used to describe and measure the surgical area. Bleb morphology, the size of the scleral lake, scleral route, and trabeculodescemetic membrane (TDM) thickness were examined. One month after CLASS, IOP significantly decreased from 20.46 ± 3.92 mmHg to 12.71 ± 2.99 mmHg, and the anterior chamber depth significantly more shallow, from 2.75 ± 0.36 mm to 2.61 ± 0.33 mm(p < 0.05). Shallow uplift occurred in 71.43% of the blebs, and 64.29% of the blebs were within 1 to 2 h; 82.15% showed mild or moderate vascular hyperemia, and the Seidel test was negative. UBM showed that all eyes had an intact TDM, with a mean thickness of 99.3 ± 22.2 μm; 21 eyes (75%) had L-type (low reflective). The scleral lake anteroposterior length, height, and transversal length were 2.247 ± 1.831 mm, 0.520 ± 0.234 mm, and 3.312 ± 0.423 mm, respectively. The TDM thickness and postoperative IOP were positively correlated, and the size of the scleral lake was not correlated with IOP reduction. Four eyes (14.29%) exhibited cyclodialysis. UBM examination indicated the aqueous humor drainage route. In the early stage after CLASS, subconjunctival and choroidal drainage routes might be the major mechanism underlying IOP reduction. Mild and moderate congestion of bleb blood vessels warrant attention to avoid early bleb scarring.

Clinical anatomy of the anterior chamber angle in congenital aniridia and consequences for trabeculotomy/cyclophotocoagulation.

Intraocular pressure lowering surgery in congenital aniridia glaucoma (CAG) can be complicated by dysgenesis of the limbal region, anterior chamber angle, iris, and lens. The anterior segments of 23 eyes (17 patients) with congenital aniridia were investigated under general anesthesia using ultrasound biomicroscopy (UBM). The structures of the anterior segment were examined: distance of ciliary body processes from the anterior chamber angle and positioning of Schlemm's canal. A surgical plan was created on the basis of these data. Schlemm's canal was detected in 21 of the 23 examined eyes. The mean distance from the anterior chamber angle was 1.3 ± 0.4 mm (range: 0.5-to 2.1 mm). The mean distance between the anterior chamber angle and the ciliary body was 561 ± 301 µm (range: 270-1,300 µm). The mean prominence of the ciliary body towards the lens was 799 ± 352 µm (range: 210-1,660 µm). This resulted in a precise UBM-based trabeculotomy. In addition, the ciliary body was detected and coagulated ab externo with a diode laser probe (810 nm) using diaphanoscopy and UBM. An initial UBM examination of the anterior segment is essential in eyes with CAG scheduled for trabeculotomy or cyclophotocoagulation. Clin. Anat. 31:64-67, 2018. © 2017 Wiley Periodicals, Inc.

Image features of lens opacity in pediatric cataracts using ultrasound biomicroscopy

To study lens opacity in pediatric cataract images captured using ultrasound biomicroscopy (UBM). The medical records of patients operated on from September 2012 to October 2013 were reviewed retrospectively. Prior to surgery, patients were placed in the supine position under sedation with oral chloral hydrate for UBM imaging. Lens morphology was evaluated by UBM examination with a 50MHz probe that was equipped with a water bag instead of the standard plastic shell. UBM images were compared to images captured from intraoperative videos. UBM examination was performed in 50 patients (including 10 infants) aged 2months to 6years. The UBM ecographic images showed features specific to pediatric cataract lenses. These features were used to define 2 types of anterior capsule of the lens, 4 types of cortex and nucleus of the lens, 3 types of posterior capsule of the lens, and membranous cataracts. Capsule morphology and the cortex density of pediatric cataracts could be evaluated before surgery using UBM imaging. Adoption of this technique could provide useful preoperative information to surgeons.

Plateau Iris in Primary Angle Closure Glaucoma

To determine prevalence and anterior segment morphology of plateau iris in patients with primary angle closure glaucoma (PACG) after laser peripheral iridotomy using ultrasound biomicroscopy (UBM). In this prospective study, 262 PACG patients and 144 normal controls underwent UBM examination. Plateau iris in a quadrant was defined by the presence of anteriorly directed ciliary process, absent ciliary sulcus, steep iris root from its point of insertion followed by a downward angulation, flat iris plane, and irido-angle contact in the same quadrant. At least 2 quadrants had to fulfill these UBM criteria. UBM analysis showed plateau iris in 83/262 (31.68%, 95% confidence interval: 26.7%-37.9%) PACG eyes, it was common in female individuals (61.44%), and patients were significantly younger than PACG patients (P=0.006). Plateau iris was found in superior quadrant in 19/83 (22.89%) eyes, inferior quadrant in 19/83 (22.89%) eyes, nasal quadrant in 21/83 (25.3%) eyes, and temporal quadrant in 24/83 (28.91%) eyes. In plateau iris patients, the central anterior chamber depth was shallower, the anterior chamber angle, the scleral-iris angle, and the sclera-ciliary process angle were significantly narrower, and the trabecular ciliary process distance and the iris ciliary process distance were significantly shorter in patients than in PACG subjects. Patients with plateau iris had significantly shallow central ACD when compared with those with pupillary block and normal eyes. After laser peripheral iridotomy, about a third of PACG eyes had plateau iris. This is clinically important because these patients can develop synechial angle closure and should be followed up closely.

In Vivo Positional Analysis of Implantable Collamer Lens Using Ultrasound Biomicroscopy

Purpose. To evaluate the anterior segment, the anatomical position of the implantable collamer lenses (ICL), and its relationship to adjacent ocular structures using Ultrasound Biomicroscopy (UBM). Methods. In a prospective study, 142 myopic eyes of 93 patients implanted with Visian ICL were subjected to UBM examination between March 2010 and January 2015. The relative position of ICL to the adjacent structure and the overall iris configuration were evaluated. The machine calibers were used to measure the minimum central distance between the ICL and anterior lens capsule (vault) and the vertical central distance between the corneal endothelium and the ICL (E-ICL). Results. The mean ICL vault was 376 ± 105 μm. The mean E-ICL was 2826 ± 331 μm. Contact between ICL and the posterior epithelium of the iris was present in all eyes. The overall iris configuration was flat in 89 eyes. Central anterior convexity was present in 41 eyes and mild peripheral iris bombe in 12 eyes. The haptics could be imaged in the ciliary sulcus in 112 eyes and at least one haptic resting on the lens periphery and zonules in 30 eyes. Conclusion. UBM can provide valuable anatomical information that allows detailed postoperative in vivo assessment of ICL.

Retrospective ultrasound biomicroscopic analysis of single-piece sulcus-fixated acrylic intraocular lenses

To evaluate the anatomic location of the haptic and optic of single-piece sulcus-fixated intraocular lenses (IOLs) and their proximity to the iris and ciliary body using ultrasound biomicroscopy (UBM). Iladevi Cataract & IOL Research Center, Ahmedabad, India. This retrospective study comprised eyes that had primary sulcus implantation of a single-piece IOL. Eyes had an intact anterior capsulorhexis that could provide uniform IOL support and a preoperative anterior chamber depth (ACD) greater than 2.7 mm. The fixation site of the haptics, distance between the optic edge and iris, optic tilt, anterior chamber angle (ACA), central ACD, and ciliary body edema were evaluated by UBM. The time from surgery to UBM examination was 7 to 85 months. Both haptics were in the sulcus in 7 of the 10 eyes, 1 haptic was abutting the iris and the other was in the sulcus in 2 eyes, and both haptics were embedded in ciliary body in 1 eye. The mean distance between the optic edge and iris was 0.16 mm +/- 0.07 (SD), 0.15 +/- 0.03 mm, and 0.38 mm, respectively. The mean ACA was 40.2 +/- 4.5 degrees (range 30.9 to 45.2 degrees), 34.1 +/- 4.5 degrees, and 44.1 degrees, respectively. The mean ACD was 3.47 +/- 0.24 mm, 3.50 +/- 0.23 mm, and 3.57 mm, respectively. No eye had optic tilt or ciliary body edema. Implantation of both haptics in the sulcus was not achieved in all eyes. The haptics and optics remained in close proximity to the posterior iris surface.

Ultrasound Biomicroscopy and Optical Coherence Tomography Imaging of Filtering Blebs after Deep Sclerectomy with New Collagen Implant

To identify the clinical and anatomic characteristics of filtering blebs after glaucoma surgery with a new biodegradable collagen implant, Ologen, using ultrasound biomicroscopy (UBM) and Visante anterior segment optical coherence tomography (OCT). The authors conducted a prospective interventional case series in 15 eyes with openangleglaucoma. The authors performed limbal-based deep sclerectomy with Ologen implantation in the scleral bed. UBM, Visante anterior segment OCT, and a complete ophthalmic examination were performed at each follow-up visit, at 1 day, and 1, 4, and 12 weeks postoperatively. Intraocular pressure (IOP) was significantly reduced (p<0.001) from a mean preoperative value of 24.2-/+6.8 mmHg (n=2.82 glaucoma medications) to a mean postoperative value of 8.1-/+1.2 (n=0), 8.5-/+1.3 (n=0), 11.7-/+3.2 (n=0), and 14.2-/+3.9 mmHg (n=0.33) at 1 day, and 1, 4, and 12 weeks, respectively. Lower IOP correlated with bleb height and low trabeculocorneal membrane thickness (r=0.79, p<0.01, r=0.91, p<0.001) based on UBM examination. Lower IOP correlated with thin bleb wall, large subconjunctival fluid spaces, and low bleb tissue reflectivity (r=0.81, p<0.01, p<0.001, and p<0.001) based on OCT examination. No postoperative complications were reported. UBM and OCT examinations are useful methods to evaluate outflow mechanisms after glaucoma surgery. Deep sclerectomy with Ologen implantation seems to be an effective and well-tolerated method to reduce IOP.

Ultrasound Biomicroscopy in Opaque Grafts With Post-Penetrating Keratoplasty Glaucoma

To evaluate the anterior segment in opaque grafts with post-penetrating keratoplasty glaucoma (PPKG) by using ultrasound biomicroscopy (UBM). An observational clinical case series of patients with opaque corneal grafts with PPKG who underwent UBM examination of the anterior chamber is reported. Indication for keratoplasty, lens status, intraocular pressure at the time of presentation, and the time of diagnosis of glaucoma were noted. Examination included slit-lamp biomicroscopy, posterior-segment ultrasound evaluation, and UBM evaluation of the anterior segment. Thirty-one eyes of 31 patients with PPKG were recruited into the study. The mean intraocular pressure was 35.5 +/- 5.8 mm Hg (range, 26-52 mm Hg). The mean time of follow-up after penetrating keratoplasty was 6.97 +/- 2.98 months (range, 2-16 months). Of the 31 patients, 11 had undergone penetrating keratoplasty for therapeutic purposes (infectious keratitis), whereas the remaining 20 had undergone keratoplasty for optical reasons. Fourteen (45.1%) patients were pseudophakic, 13 (41.9%) were aphakic, and 4 (12.9%) were phakic. The types of synechiae noted on the UBM included peripheral anterior synechiae in 30/31 (96.7%) eyes, synechiae at the graft-host junction in 13/31 (41.93%) eyes, both peripheral anterior synechiae and graft-host junction synechiae in 12/31 (38.7%) eyes, central iridocorneal synechiae in 6/31 (19.3%) eyes, and intraocular lens iris synechiae in 3/31 (9.6%) eyes. Secondary angle closure caused by anterior synechiae formation is one of the important causes of PPKG in eyes with opaque grafts. UBM serves as a useful tool for anterior-segment evaluation in such cases and can help in planning the site for glaucoma filtering surgeries and drainage devices.

Clinical applications of ultrasound biomicroscopy in diagnosis and treatment of lens subluxation

To evaluate the clinical value in diagnosis and treatment of lens subluxation using ultrasound biomicroscopy (UBM). This study comprised 29 patients (32 eyes) that had cataract with subluxated lenses due to different causes admitted into our hospital between November 2000 and January 2002. All eyes received UBM examination preoperatively and postoperatively. Capsular tension ring (CTR) implantations were performed using different technique according to UBM examination. Then all patients received phacoemulsification and intraocular lens (IOL) implantation. The location of IOL and CTR and complications were evaluated postoperatively. Different kinds of subluxated lens shown different manifestations in UBM. The degree of zonular defect can be evaluated with UBM preoperatively. With UBM examination preoperatively, extent of lens subluxation less than 1/2 quadrant in 19 eyes while more than 1/2 quadrant in other 13 eyes were observed. Postoperative UBM examination in this series shown that CTRs were holding in place except one attached to the iris root. IOLs in 29 eyes were in proper position while IOLs in 3 patients were slightly tilted. The degree and extent of lens subluxation can be evaluated using UBM examinations preoperatively, which is necessary in the selection of surgical protocol. With postoperative UBM examinations, a precise observation on the actual location of CTR and IOL can be achieved to produce an objective evaluation of the surgical outcomes.

Ultrasound biomicroscopy images: long-term results after deep sclerectomy with collagen implant.

The aim of this study was to understand the long-term outflow pathway mechanisms after deep sclerectomy - when collagen implant is resorbed - using ultrasound biomicroscopy (UBM). Forty-three eyes of 32 patients with medically uncontrolled open-angle glaucoma at least 1 year after deep sclerectomy were studied in an observational, non-randomised, consecutive case series. Postoperatively 15 eyes (35.7%) had goniopuncture with the Nd:YAG laser. Four eyes (9.5%) had postoperative subconjunctival injections of mitomycin C and two eyes (4.7%) had an injection of 5-fluorouracil, because of intraocular pressure (IOP) increase. Complete examination and UBM of the filtering site were performed 1-6 years after surgery. The following parameters were assessed: (1) Presence of a subconjunctival filtering bleb; (2) presence and volume of an intrascleral cavity; (3) presence of a suprachoroidal hypoechoic area. Intraocular pressure decreased significantly from 28.1+/-2.5 mmHg preoperatively to 12.4+/-3.8 (range 7-25) mmHg at the time of UBM (at least 1 year after surgery). Forty eyes showed clinically a diffuse filtering bleb. UBM demonstrated a subconjunctival space in all eyes. In 39 eyes (92.8%) an intrascleral cavity was observed. The mean volume of this cavity was 1.8 (range 0.11-6.53) mm(3). In 19 eyes (45.2%) we observed a hypoechoic area in the suprachoroidal space. UBM examination demonstrated several aqueous humour drainage pathways. A low-reflective diffuse subconjunctival space meant persistent filtration in all eyes. More than 1 year after surgery 92.8% of eyes had a remaining intrascleral cavity. In almost half of the patients an additional suprachoroidal outflow was observed, significantly correlated with a lower IOP.

Ultrasound biomicroscopy for localization of artificial lens haptics after trans-scleral suture fixation

Correct positioning of transscleral haptics for sulcus fixation of IOL haptics may be difficult due to lack of visual control by the surgeon. We determined the haptic sites in eyes which underwent secondary IOL implantation with transscleral suturing using ultrasound biomicroscopy (UBM) (Humphrey Instruments, Inc., San Leandro, CA, USA). Eighteen eyes of 17 patients were included in the study. The follow-up time ranged from 1 to 36 months (mean: 7 months). The positions of 36 IOL-haptics were documented by UBM examination. Twelve haptics (33%) were found in the sulcus, whereas 18 haptics (50%) were located posteriorly to the sulcus. Six haptics (17%) were identified anteriorly to the sulcus. There were no complications resulting from dislocation. In one of the eyes, suture infection occurred requiring surgical revision and antibiotic therapy.