Ultrasound Biomicroscopy Research Articles

Quantitative analysis of iridocorneal angle and ciliary cleft structures in canine eyes using ultrasound biomicroscopy

IntroductionThis study aimed to examine the relationship between the relative opening of the ICA (RO-ICA) and the structure of the ciliary cleft (CC) using Ultrasound Biomicroscopy (UBM).Materials and methodsClinical data from 31 eyes of 17 dogs at the Veterinary Teaching Hospital of Chungbuk National University, Korea, were analyzed. RO-ICA was categorized as “Slightly Narrow”, “Narrow”, “Open”, and “Wide Open”, with eyes further grouped into “Narrow” (including Slightly Narrow and Narrow) and “Open” (including Open and Wide Open) for analysis. Statistical methods, including linear regression and average comparisons between groups, were employed to explore correlations between RO-ICA and parameters such as ICA, CC width (CCW), CC length (CCL), and CC area (CCA).ResultsThe distribution showed “Narrow” (3 eyes, 9.7%), “Slightly Narrow” (13 eyes, 41.9%), and “Open” (14 eyes, 45.2%) as the predominant categories. In the Open group, CCL and CCA were significantly larger compared to the Narrow group. A positive correlation was observed between RO-ICA and CCL, and CCA across all groups. Notably, in the Narrow group, RO-ICA demonstrated a particularly significant positive correlation with all assessed parameters, including ICA, CCW, CCL, and CCA. However, no significant correlation was observed between RO-ICA and the assessed parameters in the Open group. In conclusion, while a smaller RO-ICA generally correlates with a smaller CC, a larger RO-ICA does not guarantee a larger CC.ConclusionAdditional UBM examinations are recommended for comprehensive evaluations, particularly in cases where gonioscopy indicates an open iridocorneal angle.

Clinical features of midzonal iris pigment epithelial cysts: surprising findings revealed by ultrasound biomicroscopy.

Midzonal iris pigment epithelial (IPE) cysts are typically asymptomatic but can pose a differential diagnostic challenge by mimicking ciliary body melanoma. We conducted a case series study of the clinical characteristics of these iris cysts, particularly their shapes and sizes and associated lesions revealed by ultrasound biomicroscopy (UBM). Charts of patients with midzonal IPE cysts encountered by one or more of the authors were reviewed retrospectively. Pertinent demographic information and clinical data about these patients and their cysts were abstracted. 69 patients were identified. At initial diagnosis, patients ranged in age from 14.8 to 89.5years (median: 66.0years). Only one patient was < 30years old at diagnosis. 38 patients (55.1%) were female. 74 eyes (39 right, 35 left) contained one or more clinically identified midzonal IPE cysts. The cysts involved the right eye alone in 34 (49.3%), the left eye alone in 30 (43.5%), and both eyes in 5 (7.2%) patients. The midzonal IPE cysts were located most often inferotemporally (51.4%) and second most often temporally (23.0%). UBM imaging had been performed on 44 of the 74 affected eyes. The median largest basal diameter of the midzonal IPE cysts evaluated by UBM was 4.5mm (extremes: 1.5 to 13mm), and the median height of these cysts was 1.5mm (extremes: 0.6 to 6mm). The largest lesion was a complete ring cyst. All 3 UBM-evaluated eyes that appeared by slit lamp biomicroscopy to have two or more distinct midzonal IPE cysts were shown by UBM to have a single sausage or kidney-bean shaped partial ring cyst with radial folds between the lobules and not separate multiple cysts. UBM imaging also identified peripheral IPE cysts in 32 of 44 evaluated eyes (72.7%). Our case series confirmed previously reported findings regarding age at diagnosis and most common locations of midzonal IPE cysts. However, our UBM images revealed that at least some IPE cysts identified by slit lamp biomicroscopy as multifocal are partial ring cysts with radial folds in the cyst wall between lobules and not true independent multiple cysts. What is known Midzonal IPE cysts occur most often unilaterally and inferotemporally. Midzonal IPE cysts are frequently associated with peripheral IPE cysts. What is new UBM imaging of eyes with two-clinically detected IPE cysts showed that they were confluent as opposed to separate cysts. The median largest basal diameter of midzonal IPE cysts evaluated by UBM was 4.5 mm (extremes: 1.5 and 13 mm). The median height of midzonal IPE cysts evaluated by UBM was 1.5 mm (extremes: 0.6 and 6 mm).

Potential utility of anterior segment optical coherence tomography and biometry in differentiating plateau iris configuration from pupillary block

ABSTRACT Clinical relevance Angle closure glaucoma is one of the most common blinding diseases encountered mainly in older age groups, although it may also occur at a younger age. Identifying the underlying cause of angle closure helps in designing specific treatment strategies essential for effective disease management. Background Primary angle closure disease, caused due to pupillary block (PB) and plateau iris configuration (PIC), necessitates different management strategies. This study assessed the potential utility of anterior segment optical coherence tomography (ASOCT) and optical biometry in distinguishing PIC from PB in primary angle closure disease of the young (PACDy). Methods Patients aged 20–40 years with PACDy and age-matched healthy controls were recruited. Ophthalmic examinations included gonioscopy, ultrasound biomicroscopy, ASOCT, and biometry. Anterior chamber depth, lens thickness, axial length, central corneal thickness, lens position, relative lens position, vitreous cavity length, lens vault, relative lens vault and angle opening distance, trabecular iris space area, and trabecular iris angle were measured. Receiver operating characteristics curve analysis evaluated the discriminative ability of these parameters. Results Of the 280 eyes, 128 were normal and 152 had PACDy. Of 128 PACDy, 88 had PIC, and 64 had PB. Both PIC and PB had significantly smaller ASOCT and biometric parameters than normal eyes. However, PIC had intermediate biometric values that fell between normal eyes and PB. All the aforementioned parameters, except central corneal thickness, showed excellent discriminating ability of PIC and PB from normal eyes; however, no single parameter can strongly differentiate PB from PIC. Axial length and relative lens vault had the highest, although weak, power for discriminating PB from PIC. Conclusion ASOCT and biometry effectively distinguish PIC and PB from normal eyes, but no single parameter reliably differentiates PIC from PB. Comprehensive gonioscopy and ultrasound biomicroscopy may be necessary for accurate diagnosis in PACDy.

Ultrasound Biomicroscopy for the Detection and Characterization of Anterior Segment Cysticercosis.

Ocular cysticercosis, caused by Taenia solium larvae, presents significant public health challenges, especially in regions with poor sanitation. Traditional imaging techniques often fail to detect anterior segment cysticercosis accurately, necessitating the exploration of more advanced diagnostic modalities like Ultrasound Biomicroscopy (UBM). A retrospective observational analysis was conducted on 18 eyes from 14 patients with cysticercosis involving the anterior segment. UBM imaging was performed using a Sonomed VuMax HD ultrasound biomicroscopy machine with a 50 MHz probe. In the study, 18 eyes from 18 patients were analyzed, revealing 12 cases of conjunctival cysticercosis, 4 of anterior chamber cysticercosis, and 2 of iris cysticercosis. Patients averaged 37.89 (± 16.2) years, with a male predominance. Conjunctival cysts appeared as clear masses, occasionally eliciting inflammatory reactions. Iris involvement caused thinning near the angle, while anterior chamber cysts could displace the lens, leading to iris bombe in some instances. UBM emerges as a valuable diagnostic tool for anterior segment cysticercosis, providing detailed imaging superior to traditional methods. Its cost-effectiveness and accessibility make it particularly valuable, especially in resource-constrained settings. Future research should focus on validating UBM's diagnostic accuracy and exploring its role in monitoring disease progression and treatment response.

In Vivo Imaging Techniques for the Human Scalp: A Systematic Review of the Literature.

Scalp inflammation and alopecia are distressing conditions for which patients regularly present to dermatology. Although some diagnoses can be made clinically, others require biopsy, which carries the risk of pain, infection, bleeding, and scarring. This review examines the existing literature regarding noninvasive in vivo imaging techniques and their evidence and utility in evaluating scalp pathology, with a focus on the diagnostics of hair conditions. A systematic literature search was conducted using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines without timeframe restrictions. The PubMed and Clarivate (Web of Science) databases were searched using the terms ("imaging" OR "in-vivo imaging" OR "non-invasive imaging" OR "non-invasive in vivo imaging" "imaging," "in-vivo imaging) AND ("human scalp disorders" OR "scalp" OR "hair loss" OR "alopecia"). Peer-reviewed randomized control trials (RCTs), prospective studies, retrospective studies, and case series or reports discussing in vivo imaging of the scalp published before 2022 were selected. Forty-two studies were included and discussed; modalities included laser devices (n = 27), ultrasound (US) (n = 13), infrared thermography (n = 1), skin capacitance imaging (SCI), and ultraviolet light-enhanced visualization (ULEV) (n = 1). The most common laser devices used were reflectance confocal microscopy (RCM), multiphoton microscopy (MPM), and optical coherence tomography (OCT). US techniques included high-frequency US (HFUS) and US biomicroscopy (UBM). Quality imaging of the scalp in the setting of alopecic, neoplastic, and inflammatory diseases is highly sought after. Many of these noninvasive imaging techniques show promise, each with individual advantages and disadvantages in imaging-specific conditions. Ultimately, noninvasive imaging techniques may be used to optimize patient management and minimize morbidity associated with scalp biopsies.

What is new in imaging to assist in the diagnosis of giant cell arteritis and Takayasu's arteritis since the EULAR and ACR/VF recommendations?

Over the past decades, fundamental insights have been gained to establish the pivotal role of imaging in the diagnosis of large-vessel vasculitis, including giant cell arteritis (GCA) and Takayasu's arteritis (TAK). A deeper comprehension of imaging modalities has prompted earlier diagnosis leading to expedited treatment for better prognosis. The European Alliance of Associations in Rheumatology (EULAR) recommended in 2023 that ultrasound should be the initial imaging test in suspected GCA, and Magnetic Resonance Imaging (MRI) remains the first-line imaging modality in suspected TAK. We summarize the recent advances in diagnostic imaging in large vessel vasculitis, highlighting use of combination imaging modalities, and discuss progress in newer imaging techniques such as contrast-enhanced ultrasound, shear wave elastography, ocular ultrasound, ultrasound biomicroscopy, integration of Positron Emission Tomography (PET) with MRI, novel tracer in PET, black blood MRI, orbital MRI, and implementation of artificial intelligence (AI) to existing imaging modalities. Our aim is to offer a perspective on ongoing advancements in imaging for the diagnosis of GCA and TAK, particularly innovative technology, which could potentially boost diagnostic precision.

Advancements in equine ophthalmic imaging enhance understanding of ocular and orbital anatomy and disease in standing sedated horses.

To review data on the advances in equine ophthalmic imaging that have been made during the past 5 years and highlight advantages of using multiple imaging modalities to improve clinical observational skills and improve diagnostic accuracy. A literature review from 2019 through 2024 of equine ophthalmic digital photography, fundus photography, ocular and orbital ultrasonography (US), ultrasound biomicroscopy (UBM), confocal microscopy (CM), spectral domain optical coherence tomography (SD-OCT), radiography, CT, and MRI. Digital photography remains the cornerstone of equine ophthalmic imaging for documenting examination findings, sharing information with colleagues, and consulting with specialists. Digital images also allow for in-depth postexamination review and evaluation, often revealing subtleties that may have otherwise gone undetected during the ophthalmic examination. Advanced imaging modalities are being used more frequently in equine ophthalmology, especially those that can be used with the horses standing under sedation, including US, UBM, SD-OCT, CM, and CT. Advances in equine ophthalmic imaging have led to many new clinical discoveries and to an increase in our knowledge of ocular anatomy and diseases in the horse. Many of these advanced diagnostic imaging modalities, such as MRI, CT, SD-OCT, and CM, are cost prohibitive and require substantial operator training to ensure proficiency. However, their availability in tertiary referral centers, such as veterinary teaching hospitals and large equine clinics/practices, is becoming more widespread. Advanced equine ophthalmic imaging data contributes substantially to our general understanding of clinical and applied anatomy and improves our understanding of the underlying pathogenesis associated with specific diseases.

Ahmed's sub-flap mattress suture deep sclerectomy assessment with Ultrasound Biomicroscopy.

To assess the efficacy of adding Ahmed's sub-flap mattress suture to deep sclerectomy (DS). Forty eyes with open angle glaucoma were assigned randomly into two groups: Group A: underwent DS with Ahmed's sub-flap mattress suture. Group B: underwent conventional DS. Patients were followed up closely for 6 months with serial IOP measurements and ultrasound biomicroscopy (UBM) was used to assess the surgical site functionally and anatomically at the first and sixth month. Adding Ahmed's sub-flap mattress suture improved the IOP lowering effect of DS significantly from 43% in group B to 53% in group A at 6-month (p = 0.027). IOP in group A was at 1 week, 1 month and 6-month visits (7.9 ± 1.3, 11.7 ± 2.2 and 13.3 ± 1.9 mmHg respectively) compared to group B (10.1 ± 4.6, 14.1 ± 5.2 and 16.8 ± 4.1 mmHg respectively) (p = 0.025, 0.041 and 0.001 respectively). UBM parameters were significantly larger in group A at 1 and 6 months. Strong statistically significant negative correlations were established between IOP and all the UBM parameters apart from intrascleral lake height at the first and sixth month (p < 0.01 in all of them). Finally, significant correlations were found between IOP at 6 months and whole bleb anteroposterior length and height at 1 month (p = 0.001). Adding Ahmed's sub-flap mattress suture to routine DS is an effective economical addition that will enhance the IOP lowering effect of DS. Also, assessment of the bleb by UBM is useful in predicting the success of deep sclerectomy surgery.

Uveal Effusion Syndrome Due to WNT10A Mutation.

Uveal effusion syndrome (UES) is an exudative detachment of ciliary body, retina and choroid. Various underlying causes leads to UES-like drugs (topiramate), inflammation and hypotony. Wnt gene involvement has never been associated with UES. We report a case of bilateral UES being misdiagnosed as Vogt-Koyanagi-Harada syndrome (VKH), with Wnt gene dysfunction as the underlying trigger. A 32-year-old male presented with diminution of vision in his left eye. He was found to have choroidal detachment with retinal detachment in his left eye. Choroidal detachment was noted in the right eye. Various ocular imaging including fundus fluorescein angiography and ocular coherence tomography was done. He was misdiagnosed as a case of VKH syndrome, for which he was treated with systemic immunomodulatory therapy. However, a subclinical response was made to revisit the diagnosis. Ultrasound biomicroscopy showed supraciliary effusion. Systemic and genetic evaluation led to the detection of Wnt10A pathway mutation. UES is an entity of diagnostic challenge. Careful and thorough systemic evaluation is required to clinch the diagnosis. We reported the first case of bilateral UES recalcitrant to corticosteroids, with Wnt10A gene mutation.

IOP Reduction in Nonhuman Primates by Microneedle Injection of Drug-Free Hydrogel to Expand the Suprachoroidal Space.

Expansion of the suprachoroidal space (SCS) by a hydrogel injection has been shown to reduce intraocular pressure (IOP) in rabbits as a potential treatment for ocular hypertension in glaucoma. Here, we evaluate the safety and efficacy of this approach in hypertensive and normotensive eyes in nonhuman primates. A microneedle was used to inject a hyaluronic acid-based hydrogel or saline solution (control) into the SCS of cynomolgus monkey eyes that were either normotensive (n = 7 experimental; n = 2 control eyes) or had induced ocular hypertension (n = 6 experimental; n = 3 control eyes). IOP and the degree of SCS expansion were monitored over time by tonometry and ultrasound biomicroscopy, respectively. Safety was evaluated through slit lamp, fundus, and histology examinations. In hypertensive eyes, SCS injection with hydrogel initially reduced IOP by 47.5 ± 16.7%, and IOP returned to baseline in 38 days. In normotensive eyes, hydrogel injection initially reduced IOP by 38.8 ± 8.1% and IOP gradually returned to baseline also in 39 days. Sham injections resulted in mild IOP reduction in hypertensive eyes and normotensive eyes. The hydrogel injections were well tolerated by clinical assessments. IOP was reduced in nonhuman primates for over one month by sustained SCS expansion. This procedure was safe and simple to perform. These data confirm the translational potential of this treatment method. Further optimization of the hydrogel may provide longer durations of IOP reduction. A microneedle injection of hydrogel into the suprachoroidal space may provide a non-surgical, non-pharmacologic treatment for ocular hypertension in glaucoma patients.

Evaluation of ciliary body cysts in candidates for phakic lens implantation

PurposePhakic lens implantation in the ciliary sulcus of the eye can be complicated by coincident ciliary body cysts (CBC). We developed an ultrasound imaging and mapping protocol for these cysts.MethodsThis is a retrospective case series of all patients who underwent ICL workup at a single institution from April 2015 to October 2019. A standardized ultrasound biomicroscopy (UBM) imaging protocol was developed to screen for CBCs in either the ciliary body or sulcus. The locations and dimensions of all CBCs were graphically represented.ResultsThe prevalence of CBCs in 158 patients undergoing ICL workup was 34.8%. Among the 159 CBCs detected in 55 patients, 83 were in the sulcus (52%) and 76 were restricted to the ciliary body (48%). ICLs were implanted in 40 eyes with CBCs and 3 eyes with CBCs located within the sulcus horizontally required ICL repositioning due to ICL rotation or iris chafing.ConclusionCBCs were incidentally found in 34.8% of patients undergoing ICL workup. ICL implantation was complicated in 3 of the eyes with CBCs in the horizontal sulcus. Although CBCs are not an absolute contraindication for ICL surgery, we recommend preoperative UBM screening of the ciliary sulcus.

Prevention of Argentinian flag sign in intumescent cataracts using anterior chamber air bubble and cortical fluid release techniques

BackgroundTo investigate the efficiency of a new method for the prevention of argentinian flag sign during the process of continuous, circular, and centered anterior capsulotomy (CCC) on the anterior capsule in cortically liquefied intumescent cataracts. This study was registered in an appropriate registry and the registration number of registration was xyy11[2022]-XJSFX-087; The date of of registration was 2022-04-29.MethodsPreoperative examinations including slit-lamp examination, ocular A-scan ultrasonography, and Ultrasound Biomicroscopy (UBM) UBM were conducted on 61 patients with intumescent cataracts. Cases with cortically liquefied intumescent cataracts were selected and after staining with indocyanine green, the anterior chamber air bubble technique was used to compress the anterior capsule, and liquefied cortex was aspirated using a puncture needle. Corrected Distance Visual Acuity (CDVA) and intraocular pressure were recorded on postoperative days 1, 1 week, 1 month, and 6 months. Intraoperative and postoperative complications were documented and analyzed.ResultsFifty eyes were identified as having cortically liquefied intumescent cataracts. No cases of the Argentinian flag sign occurred, and standard capsulorrhexis was achieved, facilitating smooth phacoemulsification. All patients achieved satisfactory outcomes at follow-ups of 1 day, 1 week, 1 month, and 6 months postoperatively. Mild corneal edema was observed in three cases on the first postoperative day, with no other complications noted.ConclusionsThe anterior chamber air bubble technique combined with cortical fluid release technique can prevent the occurrence of the Argentinian flag sign in cortically liquefied intumescent cataracts, this method is simple, convenient and economic for the clinical promotion.

A rare case of bilateral malignant glaucoma after cataract surgery with capsular tension ring implantation: a case report

BackgroundBilateral malignant glaucoma induced by a capsular tension ring associated with ring-shaped cysts of the ciliary body post-cataract surgery is rare. Herein, we present a case to highlight the possibility of capsular tension ring-induced malignant glaucoma.Case presentationA 59-year-old woman underwent phacoemulsification combined with capsular tension ring implantation for cataracts and zonular fibre laxity in both eyes. Upon admission, annular ciliary masses were detected in both eyes using ultrasound biomicroscopy. Two months post-surgery, the patient experienced vision deterioration, high intraocular pressure, and an axial shallowing anterior chamber in the right eye, and responded poorly to traditional anti-glaucoma medication. Ten days later, similar symptoms appeared in the left eye. Ultrasound biomicroscopy detected contact between the ciliary body and the capsular tension ring. Subsequently, malignant glaucoma was diagnosed. Anterior and posterior capsulotomies performed peripheral to intraocular lens optics using neodymium: YAG laser restored communication and alleviated the symptoms. A one-year follow-up revealed stable intraocular pressure and anterior chamber in both eyes.ConclusionsThis is the first case report of bilateral malignant glaucoma after cataract surgery induced by capsular tension ring, which is associated with bilateral ring-shaped cysts of the ciliary body. Blockage between the ciliary body and capsular tension ring was confirmed using ultrasound biomicroscopy.

The many faces of secondary angle closure glaucoma: A practical approach to unveil.

Secondary angle closure glaucoma (SACG) can be quite puzzling and can challenge even an experienced glaucoma surgeon. Unlike primary angle closure glaucoma, SACG can have various ocular and systemic associations. A careful review of the symptoms and past ocular and surgical history cannot be overemphasized. Some of the SACG can be refractory, requiring drainage devices. However, sometimes, all it takes is a prompt laser iridotomy. This can significantly reduce ocular morbidity and, in some situations, even blindness. Gonioscopy, often an underutilized technique, is critical in making the right diagnosis. With the advent of imaging techniques such as anterior segment optical coherence tomography and ultrasound biomicroscopy, one can easily pick up the etiology and treat early. As many cases of SACG present acutely, it is critical that one makes a prompt diagnosis. We present here a video bouquet of illustrated examples of SACG and the steps to identify the cause by using different imaging techniques. Through this video, we aim to make the diagnosis of SACG a simpler, more streamlined, and logical process that will help in the accurate diagnosis and management. This video demonstrates various etiologies of secondary angle closure and methods to identify and treat the same. Secondary angle closure can occur either with or without pupillary block. SACG with pupillary block involves mechanisms such as seclusio pupillae, aphakic/pseudophakic glaucoma, phacomorphic glaucoma, and silicon oil-induced glaucoma. In contrast, there are various other etiologies causing anterior pulling or posterior pushing mechanisms that contribute to non-pupillary block SACG. We discuss all of these, along with the imaging modalities needed to identify the same. https://youtu.be/N0bIw7Uknww.

Topiramate-induced uveal effusion with myopia without angle closure: A case report

Topiramate-induced acute angle closure is a well-known entity with onset of symptoms at 2 weeks following treatment initiation. We report a 24-year-old female with blurring of vision 2 days after increasing the topiramate dose for migraine prophylaxis. Examination showed increase in manifest myopia with normal intraocular pressure and absence of angle closure. Provisional diagnosis of topiramate-induced myopia (TIM) was made, confirmed by presence of uveal effusion on B-scan and ultrasound biomicroscopy. Early presentation during the course could be the reason for isolated myopia. She was advised to stop topiramate and was started on cycloplegics. This case highlights that awareness about TIM among patients helps in prompt management, thus preventing the site-threatening acute angle closure.

Spontaneous filtering bleb: Diagnosis and treatment

Abstract: A 72-year-old patient presented with decreased visual acuity and ocular discomfort. The patient had not undergone previous ocular surgery or had a history of ocular trauma. Physical examination revealed decreased intraocular pressure (IOP) (9 mmHg), a subconjunctival filtering bleb, and hypotonic maculopathy. Ultrasound biomicroscopy revealed a fistula between the anterior chamber and the subconjunctival space at Schwalbe’s line. The patient presented no findings suggestive of systemic disease or dysmorphic facial features. Surgical closure of the fistula was attempted using multiple transconjunctival 10-0 nylon sutures and staining using trypan blue 0.06%. Although the fistula was not sealed, the bleb became flatter, IOP increased (18 mmHg), and hypotonic maculopathy resolved. Spontaneous formation of subconjunctival filtering blebs is exceedingly rare; most reported cases are associated with concomitant systemic or local disease. Our novel surgical approach successfully treated the hypotony and revealed that intraoperative use of trypan blue 0.06% in phakic patients causes temporary capsular staining.

Ultrasound biomicroscopy in dogs suggests postoperative ocular hypertension may be associated with ciliary cleft changes related to cataract surgery.

To determine whether novel pre- and postsurgical ultrasound biomicroscopy (UBM) measurements of the canine ciliary cleft (CC) are associated with postoperative ocular hypertension (POH) following cataract surgery and to explore the relationship between intraocular pressure and CC UBM measurements. Following pharmacologic mydriasis, UBM images were obtained from 31 client-owned dogs before elective cataract surgery, immediately postsurgery, and 4 to 6 hours following surgery or while experiencing POH ≥ 25 mm Hg. Presurgery and the pre- to postsurgery change in CC measurements were assessed for association with POH using individual mixed-effects logistic regression models and forward variable selection models. Linear mixed-effects models were used to evaluate the relationship of intraocular pressure to UBM measurements within the same eye across multiple time points. Presurgical measurements were not predictive of POH development. An increase in pectinate ligament distance and CC area from presurgical baseline to immediate postsurgical measurement was associated with reduced odds of developing POH, while increasing CC length (from apex to mid point on the pectinate ligament) from pre- to postsurgery and immature cataracts was associated with increased odds of POH. The change in CC morphology following cataract surgery appears more impactful in the development of POH than individual variations in presurgery CC measurements. Several changes in the CC dimensions following surgery appear associated with POH risk. This understanding of a potential mechanism of POH development opens new avenues for researching preventative measures associated with modifying surgical techniques to influence CC morphology following cataract surgery.

Preoperative Structural Risk Factors for Glaucoma After Penetrating Keratoplasty for Congenital Corneal Opacity: An Observational Study.

Post-keratoplasty glaucoma (PKG) is a major complication following penetrating keratoplasty (PKP) for congenital corneal opacity (CCO). This study aims to assess the preoperative structural risk factors for PKG following PKP for CCO using ultrasound biomicroscopy (UBM). Pediatric patients with CCO who underwent preoperative UBM and primary PKP were enrolled. Patients with anterior segment operation history or witha follow-up duration less than 12months were excluded. The structural features of the anterior segment including central corneal thickness, anterior chamber depth, angle closure range (ACR), anterior synechia range, maximum iridocorneal adhesion length, abnormal iridocorneal synechia, and lens anomalies were identified on UBM images. The medical histories were reviewed to identify clinical features. The incidence of PKG was assessed to determine significant structural and clinical risk factors. Fifty-one eyes of 51 pediatric patients with CCO were included. The median age at surgery was 8.0months, and the mean follow-up duration was 33 ± 9months. Eleven (21.6%) eyes developed PKG. The main structural risk factors were abnormal iridocorneal synechia (P = 0.015), lens anomaly (P = 0.001), and larger ACR (P = 0.045). However, a larger range of normal anterior synechia without involvement of the angle was not a significant risk factor. Preoperative glaucoma (P < 0.001) and higher intraocular pressure (P = 0.015) were clinical risk factors. A shallow anterior chamber was a unique risk factor for sclerocornea (P = 0.019). Detailed preoperative examination of iridocorneal synechia, lens, and angle closure using UBM is critical for PKG risk assessment, surgical prognosis evaluation, and postoperative management in patients with CCO.

Differences in anterior segment structure and pupillary diastolic characteristics of eyes with primary angle closure suspects under light and shade environments

Objective: To investigate the anatomical structure changes of the anterior segment and dynamic pupil changes in eyes with suspected primary angle-closure (PACS) under light and dark conditions, and their correlation with the occurrence of acute primary angle-closure (APAC). Methods: This cross-sectional study collected data from 37 PACS patients (66 eyes) who visited the ophthalmology clinic of the Second Affiliated Hospital of Harbin Medical University between September 2019 and March 2021. The patients included 12 males and 25 females, with an average age of (61.27±7.35) years. Of the 66 eyes, 58 had no history of APAC in the contralateral eye, while 8 had a history of APAC in the contralateral eye. Patients without a history of APAC in both eyes underwent the dark room prone provocative test (DRPPT), and the eyes were divided into three groups: DRPPT- (44 eyes), DRPPT+ (14 eyes), and APAC (8 eyes). The DRPPT+ and APAC groups were combined into the APAC+ group. All patients underwent ultrasound biomicroscopy (UBM) to measure the changes in various parameters under light and dark conditions, including anterior chamber angle 500 (ACA500Δ) and 1000 (ACA1000Δ), angle opening distance 500 (AOD500Δ) and 1000 (AOD1000Δ), and iris thickness 500 (IT500Δ) and 1000 (IT1000Δ). Anterior segment analysis was performed to capture the pupil changes under light and dark conditions, recording pupil diameter, maximum dilation speed (Vmax), maximum constriction speed (Vmin), and average speed (Vm). Results: There was no significant difference in the parameters between DRPPT+ group and APAC group (P>0.05). In the difference analysis, it was found that the Vm value of DRPPT- group [(0.17±0.07) mm/s] was higher than that of APAC+ group [(0.13±0.06)mm/s], and the difference was statistically significant (P<0.05). There was no significant difference in other parameters (P>0.05). Vmax was positively correlated with temporal ACA1000Δ and temporal AOD1000Δ in all patients with PACS (r=0.302, 0.260; P<0.05), Vmin was negatively correlated with temporal ACA1000Δ and temporal AOD1000Δ (r=-0.338, -0.330; P<0.05). Conclusions: The dynamic changes in the anterior segment and pupil under different lighting conditions provide insights into the risk factors and potential predictive indicators for the occurrence of APAC in PACS patients.

Safety, efficacy, and clinical outcomes of transconjunctival intrascleral fixation of an intraocular lens

BackgroundImplantation of intraocular lens in the capsular bag has become the standard of care in aphakic state. However, in the absence of capsular support, several techniques and intraocular lenses are available. Our study aims to report the safety, efficacy, and clinical outcomes of transconjunctival intrascleral intraocular lens fixation with Yamane’s double-needle technique and flanged haptics.MethodsProspective, observational study with some retrospective data collection. The study enrolled 13 patients (16 eyes) who underwent transconjunctival intrascleral fixation of an intraocular lens with Yamane’s technique between June 2017 and April 2019 at Dhahran Eye Specialist Hospital and King Fahd University Hospital. All patients underwent preoperative and postoperative comprehensive evaluation, including uncorrected and best-corrected vision, intraocular pressure, slit-lamp examination, dilated fundus examination, and ultrasound biomicroscopy. We excluded patients with visually significant coexistent pathology such as retinal diseases, glaucoma, follow-up less than three months, and combined surgery such as keratoplasty.ResultsThe mean preoperative uncorrected visual acuity was 1.50 logMAR, and it improved to 0.60 logMAR. The mean preoperative best-corrected visual acuity was 0.70 logMAR, and it improved to 0.40 logMAR. The median safety index was 2.0, and the median efficacy index was 1.58. The postoperative complications included iris capture by the intraocular lens in one eye (7.7%), haptic extrusion in one eye (7.7%), and transient cornea edema in one eye (7.7%). There were no detected reports during the follow-up period of postoperative retinal detachment, choroidal detachment, elevation of the intraocular pressure (> 25 mmHg), hypotony, hyphema, vitreous hemorrhage, or endophthalmitis.ConclusionsThe transconjunctival intrascleral fixation of an intraocular lens is safe and effective with a short learning curve and was not associated with significant intraoperative or postoperative complications.