Measurement of vitreous humor pressure in vivo using an optic fiber pressure sensor.

We conducted a study to assess the pressure difference between the aqueous and vitreous humors in rabbit eyes using a direct intraocular pressure (IOP) measurement method. A micro-optic-fiber pressure sensor was utilized for this purpose. Preliminary experiments with enucleated porcine eyes confirmed the sensor's accuracy in measuring both aqueous and vitreous humor pressure. The main study involved six healthy albino rabbits, where the sensor measured the pressure in the anterior chamber (aIOP) and posterior vitreous-cavity (pIOP). These measurements were compared to aIOP values obtained through rebound tonometry. Additionally, pre- and postoperative pressure comparisons were made after performing a vitrectomy. Results revealed a significant disparity between aqueous and vitreous humor pressures. Prior to vitrectomy, pIOP was 22.8 mmHg, over twice as high as aIOP (11.0 mmHg), but decreased to a similar level following the procedure. Comparison between the sensor measurements and rebound tonometry showed agreement in aIOP values. In conclusion, our study demonstrates that vitreous humor pressure is consistently higher than aqueous humor pressure, reaching the upper limit of normal IOP. Furthermore, vitrectomy effectively reduces pIOP, aligning it with aIOP. These findings contribute valuable insights into intraocular pressure dynamics and have implications for clinical interventions targeting ocular pressure regulation.

Change of intraocular blood flow during treatment for thyroid eye disease.

To report a sequential observational study of changes in the retinal and choroidal blood flow during medical and surgical treatments for a thyroid eye disease (TED) patient, using optical coherence tomography angiography (OCTA) and laser speckle flowgraphy (LSFG). A 28-year-old man with a history of Graves' disease diagnosed 8 months prior was presented in the active phase of TED. His clinical activity score (CAS) was 6, but without diplopia or visual loss. Intraocular pressure measurement was OD 20 mmHg and OS 24 mmHg. Thyrotropin receptor antibody (TRAb) and thyroid-stimulating antibody levels were 18.8 IU/L and 4347%. Magnetic resonance imaging revealed enlargement of both extraocular muscles and fat compartments in both orbits. The patient underwent IV pulsed steroid therapy (1 g/day, 3 days) followed by an oral prednisone for 1 month. His CAS score decreased to 4. Bilateral orbital fat decompression decreased his final CAS score to 1 in both eyes. Intraocular blood flow was measured using laser speckle flowgraphy (LSFG), and OCTA was performed. Retinal blood flow increased slightly, but choroidal blood flow showed a robust increase. Choroidal blood flow measured using both LSFG and OCTA was negatively correlated with the CAS score and TRAb. In our case report, the ocular perfusion, especially choroidal blood flow, may decrease in active TED, which may be reversed by medical and surgical treatment.

Activation of Mast-Cell-Derived Chymase in the Lacrimal Glands of Patients with IgG4-Related Ophthalmic Disease.

The purpose of this present study was to investigate the distribution and expression of chymase in the lacrimal glands (LGs) of patients afflicted with IgG4-related ophthalmic disease (IgG4-ROD). LGs from patients with severe canalicular obstruction were considered the control group. Toluidine blue staining confirmed a significant increase in the number of mast cells in the LGs obtained from the IgG4-ROD patients. In addition, immunostaining of serial sections from the LGs showed a significant increase in the number of chymase-positive cells and tryptase-positive cells in the IgG4-ROD LGs compared to the normal control LGs. The mRNA expression of chymase, tryptase, TGF-ß1, and collagen-I tended to increase in the IgG4-ROD LGs. Immunostaining of vimentin and α-smooth muscle actin (α-SMA) showed that myofibroblasts were the main cellular components in severely fibrotic regions of LGs in patients with IgG4-ROD. Linear regression analyses on the number of mast cells, chymase-positive cells, and tryptase-positive cells revealed significant positive correlations between those respective cells. Our findings suggest that chymase may play a role in the fibrotic disorder of IgG4-ROD LGs through the regulation of TGF-ß1 activation and collagen-I deposition, and that it may be a therapeutic target for patients afflicted with IgG4-ROD.

Adjustable Medial Epicanthoplasty Using a Rotational Flap for Epiblepharon Repair.

ABSTRACT: This report aimed to introduce the new adjustable rotational skin flap for epicanthoplasty in combination with traditional epiblepharon repair by the modified Hotz procedure. This retrospective study involved 25 consecutive patients with superficial punctate keratitis secondary to epiblepharon complicated with epicanthal fold who underwent the combined surgery between 2019 and 2020. The mean patient age was 11.4 years in this study with a median follow-up was 8months (range, 3-12months). The rationale of the surgery was to release vertical tension of the eyelids by dissecting dense connective tissue beneath the epicanthal fold and to form a new medial canthus using a rotational skin flap supplied by the redundant the upper and/or lower eyelid skin excised during the epiblepharon repair. Postsurgical resolution ofsuperficial punctate keratitis and patient satisfaction was achieved in all patients. Additionally, there were no complications, and no revisional surgery was required in all patients for a median 8 months follow-up period. Utilizing a rotational skin flap during epiblepharon repair is a useful adjunct during epicanthoplasty surgery. This modification is well tolerated and allows for intraoperative adjustment, whereas minimizing scarring and allowing for improved tissue relaxation.

A randomized clinical trial of triamcinolone acetonide injection for suppression of inflammation after blepharoptosis surgery.

This study aimed to determine the effectiveness of triamcinolone acetonide in suppressing inflammation after blepharoptosis surgery. The study was designed as prospective, randomized, two medical centers' clinical trial. Thirty-two patients with involutional blepharoptosis of the same degree in both eyelids underwent bilateral transcutaneous levator advancement. At the end of the surgery, 4 mg/0.1 ml of triamcinolone acetonide was injected into a randomly selected upper eyelid. The fellow eyelid was not injected and was used as control. Facial photographs were taken on day 1, week 1, month 1, and month 3, and the degree of inflammation, the margin reflex distance 1 (MRD-1), and levator function (LF) between the two eyelids of each patient were compared. The primary outcome was the selection of the less inflamed eyelid decided by the majority of three individuals unrelated to the study. MRD-1 and LF were analyzed for secondary outcomes. As a result, the injected eyelid was judged to be the less inflamed eyelid in all cases. The MRD-1 in the postoperative period less than 1 month was significantly larger in the injected eyelids than the control eyelids (P<0.03). The postsurgical MRD-1 at month 3, the postsurgical LF at all postsurgical examination times were not statistically different. Adverse complications by the injection, including ptosis, levator dysfunction, increase of the intraocular pressure, and visual disturbance were not observed. In conclusion, a triamcinolone acetonide injection after ptosis surgery is both safe and effective in reducing the early postsurgical inflammation and helpful in an earlier return to a daily routine for the patients.

Chronologic Analysis of Tear Dynamics on Blinking Using Quantitative Manometry in Healthy Humans.

PURPOSE: To analyze the tear dynamics during blinking by measuring the inner pressure of the upper lacrimal drainage system. METHODS: This observational study involved 11 healthy bi- or tricenarian volunteers. Direct manometry was performed using a fiber optic pressure sensor inserted into the conjunctival sac, upper/lower canaliculus (5 mm from punctum), and inferior lacrimal sac (15 mm from punctum) during both involuntary and intentional tight blinking. Pressure was measured 200 times/second during 3 separate blinks and then chronologically analyzed. RESULTS: In all subjects of all locations during both types of blinking, the inner pressures during the stationary eyelid closing/opening were positive/approximately zero, while a positive/negative pressure spike was observed during the eyelid closing/opening movement. The averages of the maximum pressure in the spike during the intentional tight blinking (tPmax: mm Hg) in the conjunctival sac, upper/lower canaliculus, and lacrimal sac were 8.00, 12.39/12.93, and 10.59, respectively, while for the minimum (tPmin: mm Hg), the pressures were -3.18, -3.91/-3.43, and -3.31, respectively. The tPmax and tPmin in the lacrimal duct were positively correlated with that of the conjunctival sac, which suggested synchronism of the drainage system. However, the tPmax in the canaliculus was significantly higher than that of the conjunctival sac, which suggested that tears do not flow from the conjunctival sac into the lacrimal duct during eyelid closure. CONCLUSIONS: The upper lacrimal drainage system functions as one united lumen in the lacrimal pump. The positive /negative pressure spike is essential for the lacrimal pump to efficiently eject/aspirate the tear from the lacrimal/conjunctival sac.

Impact of habitual swimming on the success of lacrimal surgery.

PURPOSE: To elucidate how factors associated with swimming affect the lacrimal ducts of swimmers. STUDY DESIGN: Prospective, interventional cohort study, METHODS: Five hundred seventy four consecutive epiphora patients were surveyed via a questionnaire regarding details of their swimming-pool usage; i.e., frequency, swim-goggles' wear, and type of pool activity (i.e., swimming vs. waist-depth walking). In this cohort, all the swimmers over 20 years old with anatomical lacrimal duct obstruction underwent surgical reconstruction. The surgical success rates at 12-months postoperative were compared using multivariable logistic regression analyses between swimmer/non-swimmer patients, those with a history of high/low frequency of pool usage, and those with high/low amount of conjunctival contact with the swimming-pool water. RESULTS: Of the patients with anatomical lacrimal duct obstruction, 6.4% were habitual swimmers; nasolacrimal duct obstruction was more common in the swimmers than in the non-swimmers' controls (89.1%/66.7%, P = 0.025). The success rate of lacrimal surgery for the swimmers with anatomical nasolacrimal duct obstruction was lower (60.6%) than of the non-swimmers (83.3%, P = 0.048). A receiver operating characteristic curve analysis of the frequency for the prediction of surgical failure showed that the threshold was 4 days/week. The success rate was statistically lower (26.7%) in the high-frequency swimmers compared to the low-frequency swimmers (88.9%, P = 0.037). However, no statistical difference in the high/low ocular surface contact to the swimming-pool water was observed (71.4%/57.7%, P = 0.56). CONCLUSION: Habitual swimmers have a high risk of nasolacrimal-duct damage retrogradely from the nasal cavity that lowers lacrimal surgery's success rate.

Compressive optic neuropathy (CON) in Graves' disease caused by hypertrophy of levator and superior rectus muscles: A case report.

RATIONALE: Enlargemento of the medial rectus is the most predominant factor of compressive optic neuropathy (CON) in Graves' disease. This case report indicates that CON could develop only from the hypertrophic superior levator and superior rectus (SL/SR) muscle in a patient with poorly controlled Graves' disease, and described the possible risk of FT3-thyrotoxicosis with a prominent goiter to develop the current rare case with a review of the literature. PATIENT CONCERNS: A 66-year-old woman undergoing endocrine management of hyperthyroidism with prominent goiter visited the Department of Ophthalmology due to right-eye upper-eyelid retraction. DIAGNOSES: At initial presentation, the right and left margin reflex distance-1 (MRD-1) was 3.2 mm and 2.1 mm, respectively, and no proptosis or visual dysfunction was observed. Despite insufficient hormonal regulation, she refused to undergo goiter removal. The upper eyelid retraction gradually worsened to 7.7 mm of MRD-1, followed by the onset of 20 prism diopters (PD) of the right hypertropia, resulting in right-eye CON after 6 months. Her free thyroxin level was 3.88 ng/dl and free triiodothyronine was 24.90 pg/ml. Computed tomography and magnetic resonance imaging showed only SL/SR enlargement in the right orbit. INTERVENTIONS: Intravenous steroid and radiation therapy resulted in visual improvement; however, a prominent upper eyelid retraction and 35PD of hypertropia remained in her right eye. Orbital decompression, upper retraction repair, and superior rectus recession were performed to prevent the recurrence of CON and correct any disfigurement. OUTCOMES: The combination of conventional intravenous steroid pulse therapy, radiotherapy, and orbital decompression was effective, and no recurrence was observed for more than 1.5-years postoperatively. LESSONS: Enlargement of the SL/SR muscle complex may independently induce the CON. We believe that strict attention should be paid to patients with triiodothyronine thyrotoxicosis with progressive eyelid retraction and hypertropia.

Rituximab Monotherapy for Compressive Optic Neuropathy With Giant Ocular Adnexal Mucosa-Associated Lymphoid Tissue lymphoma.

A rare case of compressive optic neuropathy due to giant mucosa-associated lymphoid tissue lymphoma in the orbit was presented. A 87-year-old woman was aware of a slow progressive left ocular proptosis for 10 years and presented after becoming aware of a sudden progression of the proptosis accompanying visual disturbance over the previous 2 months. Orbital imaging and a biopsy of the tumor revealed a mucosa-associated lymphoid tissue lymphoma occupying her left orbit compressing and stretching the left optic nerve. Considering her age and the additional adverse effects of external beam radiation therapy to her damaged optic nerve, rituximab monotherapy was utilized. The intervention resulted in almost complete regression without any serious adverse effect, with left eye best-corrected visual acuity improving from 12/200 to 16/20. Rituximab monotherapy can be one of the first-choice treatment options for mucosa-associated lymphoid tissue lymphoma, especially in cases with the critical damage in the optic nerve.

A Case of Serious Eye Injury Caused by a Mistaken Injection of Methylrosaniline Chloride During Vitreous Surgery.

This case involved a 75-year-old female with left-eye epiretinal membrane (ERM) and cataract who developed serious eye disorders during vitreous surgery due to methylrosaniline chloride (MRC) being mistakenly injected and applied to the retina instead of Brilliant Blue G during internal limiting membrane staining. Once realized, MRC was washed out with intraocular infusion solution, and ERM surgery was successfully completed. Postoperatively, a Descemet's fold and corneal edema, marked reduction in corneal endothelial cell density, and inner retina damage and visual field defect extending from the macula toward the temporal side were observed. MRC was found highly toxic to eye tissues. [Ophthalmic Surg Lasers Imaging Retina. 2017;48:1010-1015.].

Bioelectric impact of pathological angiogenesis on vascular function.

Pathological angiogenesis, as seen in many inflammatory, immune, malignant, and ischemic disorders, remains an immense health burden despite new molecular therapies. It is likely that further therapeutic progress requires a better understanding of neovascular pathophysiology. Surprisingly, even though transmembrane voltage is well known to regulate vascular function, no previous bioelectric analysis of pathological angiogenesis has been reported. Using the perforated-patch technique to measure vascular voltages in human retinal neovascular specimens and rodent models of retinal neovascularization, we discovered that pathological neovessels generate extraordinarily high voltage. Electrophysiological experiments demonstrated that voltage from aberrantly located preretinal neovascular complexes is transmitted into the intraretinal vascular network. With extensive neovascularization, this voltage input is substantial and boosts the membrane potential of intraretinal blood vessels to a suprahyperpolarized level. Coincident with this suprahyperpolarization, the vasomotor response to hypoxia is fundamentally altered. Instead of the compensatory dilation observed in the normal retina, arterioles constrict in response to an oxygen deficiency. This anomalous vasoconstriction, which would potentiate hypoxia, raises the possibility that the bioelectric impact of neovascularization on vascular function is a previously unappreciated pathophysiological mechanism to sustain hypoxia-driven angiogenesis.

[Chalcosis bulbi recognized 22 years after trauma].

PURPOSE: To report a case of chalcosis bulbi diagnosed 22 years after accidental entry of a foreign object into the eye. CASE: A 57 year-old woman underwent surgery for vitreous opacity and cataract of unknown cause. During the operation, an intraocular foreign body was found in the vitreous at the pars plana, and was removed. The object was a coated copper wire, 3.5 mm in length and 0.2 mm in thickness. She recalled that such a wire had accidentally entered her eye 22 years previously. Copper particles were detected by copper staining of the anterior lens capsule. RESULT: Fine, sharp metal fragments may penetrate the eye with little resistance. When the injury results in minimal subjective symptoms, the person may not seek examination by an ophthalmologist. In the present case, the foreign body was a fragment of coated copper wire. The exposed metal surface was limited and the copper probably dissolved very slowly. This may account for the lack of significant symptoms. In the Japanese literature, there are many reports of coated copper wire as foreign body in the eye, but few lead to characteristic chalcosis bulbi.