Bachelor of Science, University Of Peshawar (2005)
B of Medicine and B of Surgery, University Of Peshawar (2012)
Retinal vasculitis presents with inflammation involving the retinal vasculature as an isolated disease or in combination with other ocular or systemic conditions. This entity may be associated with a wide variety of clinical manifestations such as vascular sheathing, cotton-wool spots, retinal ischemia, and neovascularization. Often, retinal vasculitis and its complications lead to diagnostic challenges in identifying the exact etiology of the inflammation. Ancillary investigations such as fundus photography, fluorescein angiography, and more recently, adaptive optics imaging and optical coherence tomography angiography, may provide valuable information that help in establishing the exact diagnosis and initiation of appropriate therapy. In the index review, multimodal imaging features of retinal vasculitis are described. In addition, detection of vascular inflammation using novel noncontact imaging techniques has been highlighted.
View details for PubMedID 28696172
Uveitis is a spectrum of inflammatory disorders characterised by ocular inflammation and is one of the leading causes of preventable visual loss. The main aim of the treatment of uveitis is to control the inflammation, prevent recurrences of the disease, and preserve vision while minimizing the adverse effects associated with the therapeutic agents. Initial management of uveitis relies heavily on the use of corticosteroids. However, monotherapy with hi-dose corticosteroids is associated with side effects and cannot be maintained long term. Therefore, steroid-sparing agents are needed to decrease the burden of steroid therapy. Currently, the therapeutic approach for non-infectious uveitis (NIU) consists of a step-ladder strategy with the first line option being corticosteroids in various formulations followed by the use of first, second, and third line agents in cases with suboptimal steroid response. Unfortunately, the agents currently at our disposal have limitations such as having a narrow therapeutic window along with their own individual potential side-effect profiles. Therefore, research has been targeted to identify newer drugs as well as new uses for older drugs that target specific pathways in the inflammatory response. Such efforts are made in order to provide targeted and safer therapy with reduced side effects and greater efficacy. Several specially designed molecular antibodies are currently in various phases of investigations that can potentially halt the inflammation in patients with NIU. In the review, we have provided a comprehensive overview of the current and upcoming therapeutic options for patients with NIU.
View details for PubMedID 30938012
PURPOSE: The aim of this study is to evaluate the differences in the fundus autofluorescence (FAF) signal between the blue light autofluorescence (BAF) from Spectralis (Heidelberg, CA) and green light autofluorescence (GAF) 200TxTM (OPTOS, UK, in normal subjects and in patients with retinochoroidopathies (RC).METHODS: In this prospective study, FAF was performed using BL (lambda=488nm) and GL (lambda=532nm) on normal subjects and patients with RC. The corresponding pairs of BAF and GAF images from both groups were analyzed using Photoshop. The strength of the FAF signal was measured on a gray scale, where optic disc was a standard to indicate absence of AF. In addition, gray values obtained from three identical points (foveal center, and points of hypo and hyper autofluorescence) in the corresponding BAF and GAF images of normal and RC subjects were divided by the optic disc value to calculate autofluorescence signal ratio (R). The R values at fovea (R1), hypoautofluorescent point (R2), and hyperautofluorescent point (R3) were compared between BAF and GAF modalities, in normal and in RC subjects separately.RESULTS: One hundred six pairs (106 eyes) of FAF images analyzed (37 pairs: normal and 69 pairs: RC subjects). In normal subjects, the mean R1, R2, and R3 values for BAF were (1.5±0.88, 1.23±0.58, and 4.73±2.85, respectively) and for GAF were (0.78±0.20, 0.78±0.20, and 1.62±0.39, respectively). Similarly, in subjects with RC, the mean R1, R2, and R3 values for BAF were (1.68±1.02, 1.66±1.15, and 7.75±6.82, respectively) and for GAF were (0.95±0.59, 0.79±0.45, and 2.50±1.65, respectively). The mean difference in the R1, R2, and R3 ratios between BAF and GAF in normal and in RC subjects was statistically significant (p<0.001). The strength of the correlation (r) between ratios for BAF and GAF was weak or not statistically significant in both normal and RC subjects (p>0.05).CONCLUSION: The distribution and intensity of the AF signal differ in BAF and GAF and cannot be used interchangeably. In BAF, optic disc signal is always weaker than in other areas, which was not true for GAF where optic disc signal was stronger than fovea and hypoautofluorescent point in both groups.
View details for PubMedID 30617430
To evaluate the role of vitreomacular adhesion (VMA) in visual and anatomic outcomes in patients with non-infectious uveitis.Phase 2 clinical trial PARTICIPANTS: Data from the Safety, Tolerability, and Efficacy of Tocilizumab in Patients with Non-infectious Uveitis (STOP-Uveitis) study was analyzed.In the STOP-Uveitis study, patients with non-infectious uveitis (NIU) received monthly intravenous infusions of either 4 or 8?mg/kg tocilizumab until month 6 (M6). Spectral domain optical coherence tomography (SD-OCT) images of patients that completed M6 of the study were analyzed at baseline to stratify the patients by the presence (VMA+) or absence (VMA-) of VMA. Patients with vitreomacular traction (VMT) or epiretinal membrane causing structural abnormalities within center 1?mm were excluded. All images were graded by two independent graders.Mean change in best-corrected visual acuity (BCVA), central retinal thickness (CRT), and vitreous haze (VH) at M6.Out of 37 patients randomized in the STOP-Uveitis study, 48 eyes (27 patients) were eligible based on the study criteria. At baseline, 19 eyes were classified as VMA+, and 32 eyes were classified as VMA-. The distribution of two doses of TCZ (4?mg/kg and 8?mg/kg) were similar between the two groups. At M6, the mean improvement in BCVA was 2.00?±?5.3 and 6.50?±?7.98 letters in the VMA+ and VMA- groups, respectively (p?=?0.02). The mean improvement in CRT was 34.85?±?72.36 and 80.37?±?157.21??m in the VMA+ and VMA- groups, respectively (p?=?0.18). Similarly, the mean change in VH was -?0.65?±?0.47 and -?0.76?±?0.71 in the VMA+ and VMA- groups, respectively (p?=?0.32). Out of 16 eyes with VMA at baseline, 3 eyes developed posterior vitreous detachment (PVD) at M6. The mean change in BCVA was significantly higher (p =?0.02), while CRT and VH score were similar (p?>?0.05) in eyes with PVD compared to eyes with persistent VMA.The absence of VMA or development of PVD in eyes with VMA seems to have a beneficial effect on the vision of subjects receiving treatment for uveitis. Therefore, patients with uveitis should be assessed using SD-OCT for the presence of vitreomacular interface abnormalities.
View details for DOI 10.1186/s12348-019-0179-6
View details for PubMedID 31325001
Uveitis consists of a spectrum of inflammatory disorders characterized by ocular inflammation. The underlying pathophysiology consists of a complex interplay of various inflammatory pathways. Interleukin 6 is an important mediator of inflammation in uveitis and constitutes focus of research toward development of newer biological therapies in the management of non-infectious uveitis.Pan-blockade of the inflammatory pathways with steroids is generally the first step in the management of acute non-infectious uveitis. However, long-term therapy with steroids is associated with systemic and ocular side effects, thereby necessitating the need for development of steroid sparing agents. IL-6 is a cytokine produced by various immune cells, in response to molecular patterns and affects multiple inflammatory cells. In particular, IL-6 is involved in differentiation of CD-4 cells into Th-17 cells that have been shown to play a significant role in various immune-mediated diseases such as uveitis. This broad-spectrum immunomodulatory activity makes IL-6 an excellent target for immunomodulatory therapy. Tocilizumab was the first IL-6 inhibitor to demonstrate efficacy in humans. It inhibits IL-6 from binding to both membrane-bound and soluble receptor and can be administered via intravenous (IV) and subcutaneous (SC) routes. It has been FDA approved for treatment of rheumatoid arthritis (RA) and juvenile idiopathic arthritis (JIA). Following the approval in systemic diseases, its efficacy was demonstrated in various uveitis studies including a phase 2 clinical trial (STOP-Uveitis). Overall, tocilizumab has shown a good safety profile with the risk of malignancy consistent with that expected in patients with rheumatoid arthritis. However, tocilizumab therapy has been shown to increase the risk for gastrointestinal perforation and dose-dependent neutropenia. Following the success of tocilizumab, several other agents targeting the IL-6 pathway are in the pipeline. These include sirukumab, siltuximab, olokizumab, clazakizumab, and EBI-031 which target IL-6; Sarilumab and ALX-0061 act on the IL-6 receptor.Studies have shown that IL-6 inhibitors can be effective in the management of NIU. In addition, the levels of IL-6 are elevated in other ocular vascular diseases such as retinal vein occlusion and diabetic macular edema. The roles of IL-6 inhibition may be broadened in the future to include the management of retinal vascular diseases and non-uveitic macular edema.
View details for DOI 10.1186/s12348-019-0182-y
View details for PubMedID 31523783
View details for Web of Science ID 000442912501050
View details for Web of Science ID 000442932807084
View details for Web of Science ID 000442912508138
View details for Web of Science ID 000442912505014
Background: Vessel flow density (VFD) may provide important information regarding perfusion status. Diurnal variation in VFD of choriocapillaris has not been reported in literature. In the index study, optical coherence tomography angiography (OCTA) was used to assess the diurnal variation of the VFD in the choriocapillaris of subjects with no known ocular disease.Methods: Fifty eyes with no known ocular disease (25 subjects) were included. OCTA images were acquired using AngioVue (Optovue, Fremont, CA, USA) at two different time points on a single day: 9:00 AM and 6:00 PM. Macular cube scan protocol (3*3mm) centered on the fovea was used. Automatic segmentation of the retinal layers and choriocapillaris was performed using ReVue software, which was also used to measure the choriocapillaris VFD. Horizontal line scan passing through fovea was obtained by the device at both time points to measure the subfoveal choroidal thickness (CT). Linear measurement tool of software was used to measure subfoveal CT according to a standardized reproducible method. Wilcoxon signed-rank test was used to assess the differences in choriocapillaris VFD and subfoveal CT at the two time points. Correlation between change in choriocapillaris VFD and subfoveal CT at the two time points was assessed using the Pearson correlation coefficient (r).Results: The mean age of the subjects was 31.96±11.23years. Choriocapillaris VFD was significantly higher at 9:00 AM compared to 6:00 PM (P<0.0001) with mean choriocapillaris VFD of 68.74±4.80% at 9:00 AM and 67.57±5.41% at 6:00 PM, with a mean diurnal amplitude of 1.17%. Mean subfoveal CT was 287.74±61.51m at 9:00 AM and 270.06±60.73m at 6:00 PM. Subfoveal CT was also significantly higher at 9:00 AM compared to 6:00 PM (P<0.0001) with a mean diurnal amplitude of 17.68m. Change in choriocapillaris VFD correlated with change in subfoveal CT (r=0.87, P<0.001).Conclusion: OCTA demonstrated significant diurnal change in choriocapillaris VFD in subjects without any ocular disease with VFD being higher in the morning and lower in the evening. Decrease in choriocapillaris VFD in the evening correlated with a reduction in subfoveal CT.
View details for PubMedID 30338130
View details for PubMedID 31047386
To report the primary endpoint analyses of the safety and efficacy of 2 different doses of intravenous (IV) infusions of tocilizumab (TCZ), an IL-6 inhibitor, in eyes with noninfectious intermediate uveitis, posterior uveitis, or panuveitis.Randomized, controlled, multicenter clinical trial.STOP-Uveitis is a randomized, open-label safety, efficacy, and bioactivity clinical trial conducted at 5 clinical centers across the United States. The study evaluated the role of TCZ in patients with noninfectious uveitis (NIU). Thirty-seven patients with NIU were randomized into one of 2 treatment groups in a ratio of 1:1. Group 1 received IV infusions of 4 mg/kg TCZ and group 2 received IV infusions of 8 mg/kg TCZ. Infusions were given every 4 weeks in both groups until month 6 (primary endpoint). Primary outcome measure was incidence and severity of systemic and ocular adverse events through month 6. Secondary outcome measures included mean change in visual acuity (VA), vitreous haze (VH), and central macular thickness (CMT) at month 6.A total of 37 patients were randomized in the study. At month 6, 43.5% of patients who had the potential for a 2-step decrease in VH demonstrated a 2-step decrease (40% in Group 1 and 46.1% in Group 2). Mean change in CMT was -83.88 ± 136.1 ?m at month 6 (-131.5 ± 41.56 ?m in Group 1 and -38.92 ± 13.7 ?m in Group 2). Mean change in VA was +8.22 ± 11.83 ETDRS letters at month 6 (10.9 ± 14.6 in Group 1 and 5.5 ± 7.8 in Group 2). Repeated infusions of TCZ were well tolerated.Repeated IV administrations of TCZ are well tolerated. TCZ (both 4 and 8 mg/kg) is effective in improving VA and reducing VH and CMT in eyes with noninfectious intermediate uveitis, posterior uveitis, and panuveitis.
View details for PubMedID 28887113
To assess normal vessel flow density (VFD) in macular and peripapillary regions of eyes with no known ocular pathology using optical coherence tomography angiography (OCTA).AngioVue (Optovue, Fremont, CA, USA) was used to capture OCTA images. A 3 × 3 mm grid and a 4.5 × 4.5 mm grid was used to scan parafoveal and peripapillary regions, respectively. ReVue software was utilized to measure VFD in five sectors within the inner two circles of ETDRS grid in macular region and correlated to retinal thickness of same sectors. At optic disc, VFD was calculated in six sectors based on Garway-Heath map. Area and morphology of foveal avascular zone (FAZ) was correlated with VFD in central 1 mm. The influence of myopia on mean VFD was also assessed.Twenty-four eyes (mean age: 30 years) were analyzed. Mean VFD in macular sectors was 43.5 (±4.5) and 45.8 (±5.0) % in superficial and deep retinal plexuses, respectively. Mean VFD was significantly higher in deep retinal plexus compared to superficial retinal plexus in all sectors except central 1 mm (p < 0.05). Mean VFD in central 1 mm increases with an increase in central retinal thickness in both superficial and deep retinal plexuses (p < 0.001). Mean parafoveal VFD at level of both superficial and deep retinal plexuses decrease with an increase in spherical equivalent in myopics (p < 0.05). Mean VFD in myopics was found to be significantly lower in parafoveal region of deep retinal plexus (p < 0.05). Mean area of FAZ was 0.33 (±0.15) and 0.47 mm2 (±0.15) in superficial and deep retinal plexuses, respectively. Area of FAZ decreases with an increase in central 1 mm thickness and foveal VFD (p < 0.001).OCTA may be used to measure VFD in macular and peripapillary regions. Vessels in the parafoveal region are more densely packed in the deep retinal plexus leading to higher VFD compared to superficial plexus. Thicker retina in fovea translates into higher foveal VFD due to more compact arrangement of retinal layers and continuity of inner nuclear layer (INL). Myopia is associated with lower VFD in parafoveal region at level of deep retinal plexuses which may explain thinning of INL in myopics.
View details for PubMedID 28781889
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View details for PubMedID 31047459