Central and peripheral contrast sensitivity in thyroid eye disease

PURPOSE

Assessment of central and peripheral contrast sensitivity (CS) in thyroid eye disease (TED) with and without dysthyroid optic neuropathy (DON).

METHODS

This cross-sectional study enrolled 33 eyes of 18 treatment-naïve TED patients and 18 age- and sex-matched healthy controls for comparative analysis. A detailed ophthalmic examination included visual acuity (VA), intraocular pressure measurement, slit-lamp biomicroscopy, and CS testing (central and four peripheral regions) using Spaeth-Richman Contrast Sensitivity test was done.

RESULTS

The average age of TED patients was 47.17 ± 13.99 years and a female preponderance was noted (66.66%, n = 12). Twenty-five eyes (75.8%) were diagnosed as TED without DON, while eight eyes (24.2%) had DON. Nine eyes (27.2%) were in the active stage of disease and 29 eyes (87.8%) had proptosis. The difference in mean logMAR visual acuities between TED patients and controls was statistically insignificant (P = 0.189), but a significant difference was noted in central and total CS score (P < 0.001, Wilcoxon-Mann-Whitney test). On CS comparison between DON and non-DON eyes, a significant difference in average scores was noted in central and all peripheral areas (P < 0.05, Wilcoxon-Mann-Whitney test). With increasing clinical activity score, a statistically significant reduction was noted in CS in three out of four peripheral regions (Spearman correlation, P < 0.05).

CONCLUSION

Visual function compromise can be detected in TED in the presence of intact VA, by testing CS. Peripheral CS deteriorates with increasing inflammation and in DON. Serial monitoring of both central and peripheral CS may help in diagnosing DON early.

Blood within the bone: orbital intraosseous venous malformation

PURPOSE

Description of clinical features, radiological characteristics, and management strategies in primary orbital intraosseous venous malformation (OIVM) with pertinent literature review.

METHODS

A retrospective analysis including clinical, radiologic, operative, and histopathological data of six cases of histopathologically proven OIVM was done. A comprehensive literature review was conducted using online databases and augmented with manual search to identify reported cases of OIVM.

RESULTS

Study data showed five females and one male in young to middle-age group, with an average age of 30 years (range: 20-48 years). Proptosis was noted in five cases (83.33%), and the duration of symptoms ranged from 6 months to 10 years. Frontal and zygomatic bones were most frequently affected and expansile bony lesion was the most common CT scan finding. Three patients underwent pre-operative embolization of feeders followed by en bloc excision of mass and surgical reconstruction (50%); one patient was managed with partial excision (16.66%) while two were regularly followed-up after incision biopsy (33.33%). Histopathology revealed vascular spaces with endothelial lining, separated by bony trabeculae in all patients. Follow-up periods ranged from 6 to 48 months and no recurrence or progression were noted.

CONCLUSIONS

OIVM is an exceptionally rare disorder with a gradually progressive benign course. Ophthalmologists need to be mindful of this entity during patient evaluation as it has propensity for large volume blood loss intra-operatively, owing to its vascular nature. Complete excision with reconstruction of resultant defect is the preferred treatment strategy and without known recurrence.

Post-chemotherapy changes in retinal pigment epithelium in retinoblastoma eyes

OBJECTIVE

Histopathological analysis of the retinal pigment epithelial (RPE) changes in retinoblastoma (RB) cases who received pre-surgical chemotherapy.

DESIGN

Laboratory-based observational study.

METHODS

Five-year analysis was performed to identify Retinoblastoma cases who underwent enucleation after receiving systemic chemotherapy. Grossly, RPE cells were observed in flat preparation in small calottes by staining with fluorescein stain in the raw specimens. They were documented under the objective of compound microscope and compared with hematoxylin and eosin-stained slides in the permanent tissue sections.

RESULTS

Out of 51 cases of RB, post-chemotherapy enucleation was performed in 17 cases. Mean age of enucleation was 3.2 years. Endophytic RB (11 cases, 64.71%) was more common than the exophytic variety. Choroidal involvement was noted in 8 cases (47.06%), and optic nerve involvement was seen in 5 cases (29.4%). Focal and diffuse RPE changes were seen in one case each (5.88%). Central RPE cell changes near the cell nucleus were seen in all 17 cases (100%), which were documented by both fluorescein and Hematoxylin and eosin stain (100%). Drusens were observed in 8 cases (47.06%), and RPE proliferations were seen in 3 cases (17.65%).

CONCLUSION

The study highlights the characteristic histopathological RPE changes after systemic chemotherapy in RB cases. These changes may be attributable to cell nucleus damage after chemotherapy.

Use of transcranial low-intensity focused ultrasound for targeted delivery of stem cell-derived exosomes to the brain

The blood-brain barrier (BBB) presents a significant challenge for targeted drug delivery. A proposed method to improve drug delivery across the BBB is focused ultrasound (fUS), which delivers ultrasound waves to a targeted location in the brain and is hypothesized to open the BBB. Furthermore, stem cell-derived exosomes have been suggested as a possible anti-inflammatory molecule that may have neural benefits, if able to pass the BBB. In the present study, transcranial low-intensity focused ultrasound (LIFU), without the use of intravenous microbubbles, was assessed for both (1) its ability to influence the BBB, as well as (2) its ability to increase the localization of intravenously administered small molecules to a specific region in the brain. In vivo rat studies were conducted with a rodent-customized 2 MHz LIFU probe (peak pressure = 1.5 MPa), and injection of labeled stem cell-derived exosomes. The results suggested that LIFU (without microbubbles) did not appear to open the BBB after exposure times of 20, 40, or 60 min; instead, there appeared to be an increase in transcytosis of the dextran tracer. Furthermore, the imaging results of the exosome study showed an increase in exosome localization in the right hippocampus following 60 min of targeted LIFU.

Navigation-guided transcaruncular orbital optic canal decompression in indirect traumatic optic neuropathy: long-term outcomes

PURPOSE

To determine the surgical outcomes using navigation-guided transcaruncular orbital optic canal decompression (NGTcOCD) and investigate the relationship between visual prognosis. visual evoked potential (VEP), association with DeLano type of optic canal and Onodi cells in patients with indirect traumatic optic neuropathy (TON).

DESIGN

Prospective observational.

METHODS

Fifty-two consecutive patients with indirect TON unresponsive to steroid therapy were divided into three groups where Group I comprised of cases with optic canal fracture who underwent NGTcOCD, Group II without optic canal fracture who underwent NGTcOCD and Group III, no-decompression group who chose not to undergo NGTcOCD. An improvement in visual acuity (VA) at 1 week, 3 months and 1 year and amplitude and latency of VEP at 1 year were considered as primary and secondary outcomes, respectively.

RESULTS

The mean VA improved from 2.55±0.67 and 2.62±0.56 LogMAR at presentation to 2.03±0.96 and 2.33±0.72 LogMAR at final follow-up among Group I and Group II patients, respectively (p<0.001 and p=0.01). Statistically significant improvement observed among both the Groups in VEP amplitude (p=<0.01) and among Group II in VEP latency (p<0.01). Both Group I and Group II patients have better outcomes than patients in no-decompression group. VA at presentation and Type 1 DeLano optic canal were observed as significant prognostic factors.

CONCLUSIONS

NGTcOCD serves as a minimally invasive transcaruncular route to the optic canal which enables ophthalmologists to perform decompression from the anterior-most orbital end under direct visualisation. Patients with indirect TON with or without optic canal fracture and unresponsive to steroid therapy when managed with NGTcOCD have shown comparable and superior outcomes.

Crouzon syndrome and the eye: An overview

The current literature review aims to evaluate the ocular findings and associated ophthalmic features in Crouzon syndrome. Craniosynostoses are syndromes characterized by premature fusion of sutures of the skull and Crouzon syndrome is the most common of the craniosynostosis syndromes. Early fusion of sutures results in craniofacial anomalies, including abnormalities of the orbits. To prepare this review of the ophthalmic findings in this disorder, an organized search on online databases such as PubMed, Scopus, Cochrane Library, and Ovid was carried out. The key terms searched were "Crouzon", "craniosynostosis", "eye" and "ophthalmic", and 51 research items were found. A total of 17 articles were included after scrutiny of the databases and a further 25 articles were added after augmented search. A detailed review was performed from the final 42 articles. A comprehensive description of associated anomalies is given along with the author's own technique of surgical management in cases with Crouzon syndrome having bilateral luxation bulbi with exposure keratopathy. However, for optimum management of cranial and oculo-facial dysmorphisms, a multidisciplinary team of specialists is required.

Ultra-widefield fundus fluorescein angiography in pediatric retinal vascular diseases

Purpose:

To describe the utility of RetCam ultra-wide-field fundus fluorescein angiography in pediatric retinal vascular diseases.

Methods:

A retrospective chart review was carried out in 43 eyes of 22 pediatric patients who were diagnosed or suspected to have a retinal vascular disease. Fluorescein angiography was carried out using the 130 degree lens of RetCam 3. Fluorescein angiography guided treatment (laser/cryotherapy) was carried out wherever required.

Results:

Diseases studied included - coats disease, familial exudative vitreoretinopathy, retinopathy of prematurity, congenital retinal folds, double optic nerve head, persistent fetal vasculature and incontinentia pigmenti. RetCam assisted fluorescein angiography was helpful in establishing a diagnosis in 4 patients (18%), in decision making regarding treatment in 18 patients (82%), in deciding need for retreatment in 5 patients (23%), helped in staging of disease in 5 patients (23%) and in detecting clinically subtle findings in 6 patients (27%).

Conclusion:

RetCam assisted FFA is extremely useful to document peripheral retinal vascular pathologies in pediatric patients and helps to take crucial therapeutic and retreatment decisions.

Nanomonitors: electrical immunoassays for protein biomarker profiling

Aims: The objective of this research is to develop a ‘point-of-care’ device for early disease diagnosis through protein biomarker characterization. Here, we present label-free, high sensitivity detection of proteins with the use of electrical immunoassays that we call nanomonitors. Materials & methods: The basis of the detection principle lies in the formation of an electrical double layer and its perturbations caused by proteins trapped in a nanoporous alumina membrane over a microelectrode array platform. Results & discussion: High sensitivity and rapid detection of study protein biomarkers for cardiovascular diseases, C-reactive protein (CRP) and myeloperoxidase (MPO) in pure and clinical samples through label-free electrical detection were achieved. CRP and MPO were detected in pure solutions with a lower detection limit of 200 pg/ml and 500 pg/ml, respectively. These two study proteins were also detected from multiplexed samples containing a mixture of both proteins as well as human serum samples. Conclusions: The performance parameters of the nanomonitors, such as speed of detection on the order of minutes, volume of reagents of a few microliters and low cost per assay are comparable to traditional assay methods, such as ELISA. In addition, nanomonitors also provide the advantages of being a label-free technique with large linear dynamic range of detection and a significant reduction in the size of assay, thus making it an ideal candidate for a clinical diagnostic ‘lab-on-a-chip’ device for protein biomarker profiling and hence early disease diagnosis.