Clinical, microbiologic, and treatment outcomes of dematiaceous fungal keratitis - A retrospective study

PURPOSE

Dematiaceous fungi, the third most common causative organism of fungal keratitis, constitute 3.5% to 43.5% of fungal keratitis worldwide. Several studies on filamentous fungi (Aspergillus and Fusarium) are available as opposed to that on dematiaceous fungal keratitis. This study aims to describe the profile of dematiaceous fungal keratitis in South India.

METHODS

This institutional cohort study on culture-proven dematiaceous fungal keratitis was performed in a single ophthalmology referral center in South India for a 6-year period. Records were analyzed for demographic, clinical, microbiological, and treatment outcomes for 3 months from the date of presentation.

RESULTS

This study comprised 312 cases involving dematiaceous fungal keratitis (DFK). During the study period, DFK accounted for 10% of microbial keratitis and 24.6% of fungal keratitis cases. The mean (standard deviation) age was 54 (14) years. Males were commonly affected (73.4%). Keratitis was ≤1/3rd depth in 47.8% of cases. Fifty-four cases (17.3%) demonstrated surface pigmentation, and 69 cases (22.1%) had endothelial plaque. Curvularia spp. (99 eyes, 31.7%) was the most common fungal isolate among the speciated fungi. Topical medications resulted in the healing of 63.5% of cases. A total of 193 cases (79%) healed, and 49 cases had to undergo therapeutic penetrating keratoplasty (TPK). Early TPK was performed for 20 cases (40.8%). Seventeen eyes (34.6%) maintained clear grafts at the end of 3 months.

CONCLUSION

In this extensive study on DFK, we report a high incidence of this group of fungal keratitis. We found an excellent healing rate in our cohort of patients.

Retrospective multifactorial analysis of ocular firecracker injuries and review of literature

Purpose

To analyse demographics, risk factors, clinical features, functional, anatomical outcomes, and prevalence of blindness in firecracker injury patients presenting to a tertiary eye care centre.

Methodology

A retrospective analysis of ocular firecracker injuries patients who presented to our hospital from April 2018 to March 2019 was performed. A total of 114 patients with a minimum follow-up of 3 months were included. The parameters recorded were demographics, mode of injury, type of cracker, baseline and last follow up best-corrected visual acuity (BCVA), anterior and posterior segment findings, seidel's test, intraocular pressure, gonioscopy, treatment, functional and anatomical outcomes. Investigations in form of B Scan, X-ray, or CT scan were undertaken whenever indicated.

Results

A total of 132 eyes of 114 patients were analysed. The mean (SD) age was 18.96 +/−15.4 years (range 3–71 years). Seventy-four (64.91%) patients were ≤ 18 years of age. The male-to-female ratio was 4:1. The ratio of right: left eye involvement was 1:1. Eighteen patients (15.79%) had bilateral involvement. A total of 125 eyes had closed globe injury, 7 eyes had open globe injury and 17 patients needed hospital admission for management. The mean (SD) baseline BCVA was 0.54(+/−0.75). The mean (SD) final BCVA improved to 0.23(+/−0.62) till the last follow-up. The final outcome was good in most patients, except 5 eyes (3.78%) which resulted in near/total blindness.

Conclusion

Firecracker injuries are a major cause of irreversible blindness, especially among the younger age group. Prompt diagnosis with meticulous management can prevent devastating sequelae.

Brittle cornea syndrome: A tale of three brothers

Brittle cornea syndrome (BCS) is a genetic connective tissue disorder with discernible ocular features such as blue scleral and thin cornea that predominantly presents in younger children. We herein describe cases of three siblings with BCS, two of whom presented to us with open globe injuries following trivial trauma. Clinical examination of the other eye in both showed diffusely thin corneas and blue sclera. A systemic evaluation revealed sensorineural hearing loss and hyperextensible joints. The third sibling was screened and found to have features concurrent with BCS. This report highlights the challenges faced in the management of ocular injuries and consecutive complications in these patients.

Congenital corneal anesthesia: A case series

Congenital corneal anesthesia (CCA) is an extremely rare condition where the cornea is affected in isolation or as a part of congenital syndrome, or can be associated with systemic anomalies. This case series of 12 eyes provides an overview of various clinical presentations and their final treatment outcomes. The average age of presentation was 3.2 years with a female preponderance (75%). Fifty percent of the patients had bilateral involvement and 50% had corneal ulcers at presentation. Two eyes required therapeutic keratoplasty for corneal perforation. All patients had isolated CCA except for one who had an associated hereditary and sensory autonomic neuropathy.

Corneal Perforation Secondary to Rosacea Keratitis Managed with Excellent Visual Outcome

Introduction: Ocular Rosacea is a poly etiological chronic inflammatory disease with heterogeneous clinical manifestations. It is primarily a dermatologic disease, which often manifests in the eyes affecting eyelids, conjunctiva, and cornea. The leading role in the pathological process belongs to the disruption of regulatory mechanisms in the vascular, immune, and nervous systems. The varied manifestation can be erythematous pustular lesions on the face, chronic blepharitis, meibomian gland dysfunction, evaporative dry eye, peripheral corneal ulceration, corneal scarring, perforation, and neovascularization.    Case: We describe a rare case report of a 43-year-old male with progressive ocular manifestations of rosacea keratitis. Slit-lamp biomicroscopic examination revealed squamous blepharitis, telangiectatic vessels with obliterated meibomian glands, circumcorneal congestion, peripheral corneal perforation of 2x2 mm at 4 0 clock, shallow anterior chamber(AC) with positive seidel’s in the left eye. Fundoscopy showed serous choroidal detachment(CD). Snellen’s Best Corrected Visual Acuity(BCVA) was 20/240 with Intraocular pressure measured was 5 mmhg. The patient was managed with topical loteprednol, moxifloxacin, carboxymethylcellulose medications along with cyanoacrylate glue and bandage contact lens and had excellent visual acuity of 20/20 with a follow-up of 1 year. Conclusion: Ocular rosacea perforation has been reported in chronic cases and may not always require amniotic membrane transplant, patch grafting, or keratoplasty. If managed meticulously with cyanoacrylate glue and BCL can have excellent outcomes. Eye specialists should be alerted that the key to a successful outcome is excellent control of inflammatory activity and differentiating this non-infectious keratitis from other keratitis before commencing treatment.

Retrospective multifactorial analysis of Pythium keratitis and review of literature

Purpose:

The aim of this work was to study the demographic profile, clinical diagnostic features, challenges in management, treatment outcomes, and ocular morbidity of microbiological culture-proven Pythium keratitis in a tertiary eye care hospital in South India.

Methods:

Retrospective analysis of microbiologically proven Pythium keratitis patients was performed at a tertiary eye center from October 2017 to March 2020. Demographic details, risk factors, microbiological investigations, clinical course, and visual outcomes were analyzed.

Results:

Thirty patients were analyzed. The mean age was 43.1±17.2 years. Most common risk factors were history of injury in 80% and exposure to dirty water in 23.3%. Visual acuity at baseline was 20/30 to perception of light (PL). The most common clinical presentation was stromal infiltrate and hypopyon in 14 (46.6%) patients each. The microbiological confirmation was based on culture on blood agar and vesicles with zoospores formation with incubated leaf carnation method. Seven (23.3%) patients improved with topical 0.2% Linezolid and topical 1% Azithromycin, 19 (63.3%) patients underwent Therapeutic keratoplasty (TPK) and 4 were lost to follow-up. Seven (23.3%) patients had graft reinfection, and 3 (10%) developed endophthalmitis. The final visual acuity was 20/20- 20/200 in 6 (20%) patients, 20/240-20/1200 in 5 (16.6%) patients, hand movement to positive perception of light in 16 patients and no perception of light (Pthisis Bulbi) in 3 (10%) patients.

Conclusion:

P. insidiosum keratitis is a rapidly progressive infectious keratitis with prolonged and relapsing clinical course. It usually results in irreparable vision loss in majority of the patients. Prompt diagnosis, clinical awareness, and specific treatment options are needed for successfully managing this devastating corneal disease.

Effect of congenital ptosis correction on corneal topography- A prospective study

Purpose:

The aim of this study was to evaluate the changes in corneal topography, cycloplegic refraction, and best-corrected visual acuity (BCVA) after ptosis correction surgery in patients with congenital ptosis.

Methods:

Our study represents a prospective observational study conducted on 27 eyes of 21 patients with congenital ptosis. All patients underwent complete ophthalmological evaluation, cycloplegic refraction, and baseline Orbscan prior to ptosis surgery. At 6 months postoperative review, the cycloplegic refraction and Orbscan were repeated to evaluate the changes in these parameters. The main outcome measures in our study were Steepest K, Inferior-Superior Asymmetry (I-S Asymmetry), cycloplegic refraction and BCVA.

Results:

A significant decrease in Steepest K postoperatively (P < 0.001) was noted. Superior K and Inferior K also decreased, but the decrease in Inferior K was statistically significant (P = 0.044). However, change in I-S Asymmetry was not significant. Variation in BCVA, and cycloplegic sphere and cylinder was minimal. Sim K astigmatism, Surface Regularity Index, I-S Asymmetry and Central Corneal Thickness did not show significant variation.

Conclusion:

Ptotic eyelid constantly presses on the cornea causing significant changes in corneal contour and surface remodeling. This pressure when relieved, results in significant flattening and regression of anterior corneal surface to its near normal anatomy. This further resulted in improvement of corneal surface irregularity and symmetry.

Successful management of pediatric pythium insidiosum keratitis with cyanoacrylate glue, linezolid, and azithromycin: Rare case report

PURPOSE

Pythium insidiosum causes a rare sight-threatening keratitis and is a devastating ocular pathology with a high morbidity. It is frequently mistaken as fungal keratitis. Here we highlight a rare case of pediatric Pythium insidiosum keratitis which was successfully managed using an antibiotic combination of linezolid and azithromycin with cyanoacrylate glue.

CASE DESCRIPTION

A 9-year-old young male child presented to our clinic with defective vision, pain, redness in the right eye for 5 days post stick injury. In the right eye, Snellen's best-corrected visual acuity (BCVA) was 6/12 which deteriorated to hand movements within 5 days of treatment. Ocular examination revealed 6 × 5 mm dry-looking mid stromal corneal infiltrate with feathery margin involving the visual axis. The clinical picture was suggestive of fungal keratitis. Corneal scraping and smear examination with 10% KOH and Gram stain revealed long slender hyaline hyphae with sparse septations. Before the culture result, the patient was started on 5% Natamycin and 1% Itraconazole hourly, but still, the infiltrate progressed. Further, P. Insidiosum keratitis was considered as the differential, which was confirmed on blood agar culture. After receiving culture results, the patient was managed with 0.2% Linezolid and 1% Azithromycin hourly. Due to the rapid progression of infiltrate, corneal melt, and younger age, cyanoacrylate glue, and bandage contact lens were used. On the last follow-up, the BCVA recovered to 6/12.

CONCLUSION AND IMPORTANCE

Prompt diagnosis, clinical awareness, and a specific treatment regime is needed for managing this devastating corneal entity. Cyanoacrylate glue due to its antibacterial properties can be a potential rescuer and can be considered for managing these cases.

The Prognostic Value of Persistent Culture Positivity in Fungal Keratitis in the Mycotic Antimicrobial Localized Injection Trial

PURPOSE

To evaluate the utility of repeat cultures at days 3 and 7 after starting antifungal medications for predicting outcomes in fungal keratitis.

DESIGN

Prespecified secondary analysis of the randomized clinical Mycotic Antimicrobial Localized Injection trial.

METHODS

Patients presenting to Aravind Eye Hospital, Pondicherry, India, with fungal keratitis and visual acuity worse than 20/70 received topical natamycin and were randomized to either receive intrastromal injection of voriconazole or topical therapy alone. All subjects received corneal cultures at date of presentation, day 3, and day 7. Outcome measures included 3-week and 3-month visual acuity and scar size, corneal perforation, and/or the need for therapeutic penetrating keratoplasty (TPK). Visual acuity and scar size were analyzed with multiple linear regression controlling for baseline measures. Survival analysis was used to analyze the risk of corneal perforation and/or need for TPK.

RESULTS

Of the 70 study subjects with fungal keratitis, 25 of 69 (36%) remained culture positive at day 3, and 20 of 62 (32%) were culture positive at day 7. Culture positivity at day 3 conferred a hazard ratio of 2.8 for requiring TPK (P = .03) but was not a statistically significant predictor of perforation, scar size, or final visual acuity. Culture positivity at day 7 had a hazard ratio of 3.5 for requiring TPK (P = .003). Those with positive cultures at day 7 had on average 3 logMAR lines worse visual acuity at 3 months (95% confidence interval 0.9 to 5.2 logMAR lines, P = .006) and 1.1 mm larger scar size at 3 months after controlling for baseline measures (95% confidence interval 0.1 to 2.2 mm; P = .03).

CONCLUSIONS

While not as predictive as day 7 cultures, culture positivity at day 3 after starting treatment is a significant predictor of the need for TPK in patients with moderate-to-severe filamentous fungal keratitis. This has applications for risk stratification, and may facilitate earlier consideration of TPK in high-risk patients.

Mycotic Antimicrobial Localized Injection: A Randomized Clinical Trial Evaluating Intrastromal Injection of Voriconazole

PURPOSE

To determine if there is a benefit to adjuvant intrastromal voriconazole (ISV) injections for primary treatment of filamentous fungal keratitis.

DESIGN

Outcome-masked, randomized controlled clinical trial.

PARTICIPANTS

Patients with moderate vision loss resulting from a smear-positive fungal ulcer.

METHODS

Study eyes were randomized to topical natamycin plus ISV injection versus topical natamycin alone.

MAIN OUTCOME MEASURES

The primary outcome of the trial was microbiological cure on 3-day repeat culture analysis. Secondary outcomes included microbiological cure on 7-day repeat culture analysis; 3-week and 3-month best spectacle-corrected visual acuity; infiltrate or scar size or both; rate of perforation; therapeutic penetrating keratoplasty (TPK); and other adverse events.

RESULTS

A total of 151 patients with smear-positive ulcers were screened and 70 were enrolled at Aravind Eye Hospital, Pondicherry, India. Baseline cultures grew Fusarium in 19 samples (27%), Aspergillus in 17 samples (24%), and other filamentous fungi in 19 samples (27%) and showed negative results in 13 samples (19%). Those randomized to ISV injection had 1.82 times the odds of 3-day culture positivity after controlling for baseline culture status (95% confidence interval [CI], 0.65-5.23; P = 0.26, bias-corrected logistic regression) and 1.98 times the odds of positive 7-day culture results, after controlling for baseline culture status (95% CI, 0.69-5.91; P = 0.20, bias-corrected logistic regression). Those randomized to ISV injection showed 0.5 logMAR lines (approximately 0.5 Snellen lines) of decreased visual acuity (95% CI, -2.6 to 3.6 lines; P = 0.75) and 0.55 mm worse infiltrate or scar size or both at 3 months after controlling for baseline values (95% CI, -0.13 to 1.25; P = 0.11). Intrastromal voriconazole injections showed a 2.85-fold increased hazard of perforation after controlling for baseline infiltrate depth (95% CI, 0.76-10.75; P = 0.12) but no difference in the rate of TPK (hazard ratio, 0.95; 95% CI, 0.44-2.04; P = 0.90).

CONCLUSIONS

There seems to be no benefit to adding ISV injections to topical natamycin in the primary treatment of moderate to severe filamentous fungal ulcers. Studies consistently suggest that voriconazole has a limited role in the treatment of filamentous fungal ulcers.

Anatomical variations of the thyroid gland: possible surgical implications

INTRODUCTION

The organogenesis of the thyroid gland in humans is often disturbed, leading to a variety of morphological variations of the gland, such as hypoplasia, ectopy, hemiagenesis and agenesis. As the morphological variations are usually diagnosed incidentally during examination for other thyroid gland diseases, the true incidence is therefore uncertain.

METHODS

This study was structured to investigate the gross anatomical features of the thyroid gland in 105 (88 male and 17 female) cadavers from the coastal belt of southern India, an endemic goitre region.

RESULTS

The pyramidal lobe was present in 61 (58 percent) male cadavers, and 52 (49.5 percent) cadavers showed the presence of the levator glandulae thyroideae. 33 percent of the specimens studied showed agenesis of the isthmus. However, the accessory thyroid tissue was found in only one cadaver.

CONCLUSION

This study highlights the various developmental anomalies of the thyroid gland, which forms a cornerstone to safe and effective surgery.

Construction of a whole body blood flow model for use in positron emission tomography imaging with [15O]water

A whole body blood flow model (WBBFM) was developed and tested using STELLA II, an icon-driven mathematical simulation software package. The WBBFM uses parallel chambers to represent gray and white areas of the brain, body organs such as lungs, heart (right and left halves), injection site, and blood sampling sites. Input values to the WBBFM include organ blood flows, organ volumes, tissue:blood partition coefficients, injected activity, and data acquisition times for a positron emission tomography (PET) camera. Input variables included an injection function (e.g., bolus), and a blood flow function (e.g., transient variations in flow). The kinetic behavior of [15O]water, a freely diffusible radiotracer employed in PET to characterize blood flow was examined by the WBBFM. The physiologic behavior of water in the human body was emulated using the WBBFM and the model's predictive value was verified by comparing calculated results with the following properties of water: diffusibility, tissue:blood partition coefficient of [15O]water, and the mixing of [15O]water with total body water. The WBBFM simulated Kety's autoradiographic method used in the estimation of regional cerebral blood flow by PET using [15O]water. The application of the model to a cognitive activation study paradigm based on Kety's method is presented and its results compared to published literature data. With appropriate modification in the half-life, tissue:blood partition coefficient, and the amount of administered radioactivity, the WBBFM should prove useful as a tool to examine kinetics of other freely diffusible radiotracers used in PET.

Dosimetry of [15O]water: a physiologic approach

Earlier dosimetry estimates for [15O]water assumed its instantaneous equilibrium with total body water. This assumption leads to an underestimation of the absorbed doses to organs with high blood flows, since the biodistribution of this short-lived radiopharmaceutical is dependent upon blood flow to organs. We have developed a physiologically based whole body blood flow model (WBBFM) using a commercially available icon-driven mathematical simulation software package and applied it to the reevaluation of [15O]water dosimetry in humans. The WBBFM uses multiple parallel compartments to represent organs, heart chambers, the injection site for [15O]water, and blood sampling sites (arterial and venous). Input values to the WBBFM include organ blood flows, organ masses, organ water volumes, organ:blood partition coefficients, injected activity and S-values of [15O]. The WBBFM is based on the same assumptions that are used in calculating regional blood flow using [15O]water and simulates the human body closely in its physiologic response. The activity in each organ is derived from the simulation and is used to calculate absorbed doses. The WBBFM calculated absorbed doses in microGy/MBq (mrad/mCi) to various organs are as follows: heart--2.66 (9.84), kidneys--2.20 (8.15), thyroid--1.83 (6.78), brain--1.66 (6.13), ovaries--1.25 (4.61), breast--1.24 (4.59), and small intestine--1.03 (3.83). These values are approximately two- to threefold higher than the earlier estimates of Kearfott [J. Nucl. Med. 23, 1031-1037 (1982)] and similar to the recent findings of Herscovitch et al. [J. Nucl. Med. 34, 155P (1983)]. We believe this approach yields more realistic dosimetry estimates for [15O]water. Accordingly, we have revised the amount of [15O]water administered during regional blood flow studies at our institution. The relative ease and accuracy of this approach suggests its usefulness in dosimetry estimation for other freely diffusible radiopharmaceuticals.

Effects of timing and duration of cognitive activation in [15O]water PET studies

The multiple injection [15O]water method offers unique opportunities for studying cognitive processing by the human brain. The influence of the duration and temporal placement of an activation task, in relation to the arrival of the radiotracer in the brain, is a fundamental methodologic question for cognitive activation studies. A quantitative positron emission tomography (PET) study of five normal volunteers was performed in which the stimulation consisted of a visual activation task (alternating checkerboard pattern) superimposed on an auditory baseline task (syllable monitoring). Ten injection conditions, with varying duration and timing of the visual activation, were used. Regional CBF (rCBF) in visual cortex was measured quantitatively using the autoradiographic method. A 20-s stimulation, centered on the bolus arrival in the brain, produced significant changes in rCBF. Because varying the duration and timing of the activation task technically violates the temporal homogeneity assumption of the autoradiographic model, a mathematical simulation was formulated to evaluate the potential influence of these variations. Results of the simulation are consistent with the PET data and suggest that activation can be limited to a narrow temporal window centered on the radiotracer uptake. The ability to observe significant changes in rCBF with short stimulation intervals is of particular interest in the use of [15O]water PET for studies of cognitive processes with a short time course.