Multidisciplinary ocular and periocular cancers meetings: implementation in a tertiary referral center and analysis over a 12-months period.

PURPOSE: The complexity of multimodal approaches in cancer management has lately led to the establishment of multidisciplinary tumor boards (MDTBs) to define targeted, patient-centered treatment strategies. However, few data are available regarding the application of this approach in Ocular Oncology. Hereby, the Authors analyze the implementation and outcomes of a trained MDTB in a tertiary ocular oncology referral center. METHODS: A retrospective descriptive analysis of MDTB meetings discussing patients with ocular and periocular cancers, over a 12-months period, was carried out. Data were grouped by main site involved, topics discussed and final clinical decisions therefore taken. Meetings were held by a constant 'Core team' or - when required - by a broader 'Extended team'. RESULTS: During the observational period 86 cases were discussed. In 27 patients ocular surface tissues were involved (31%), in 25 patients orbital tissues (29%), in 22 patients eyelids (26%), and in 12 patients intraocular tissues (14%). In 13 cases (15%) naïve or referred new patients, in 34 cases (40%) imaging or histopathologic reports and in 39 cases (45%) treatment plans were discussed. Regarding final decisions, a treatment plan was scheduled in 47 cases (55%) and a diagnostic ascertainment was required in 27 patients (31%); locally advanced and/or systemic diseases were referred or teamed up with other specialists in 12 cases (14%). CONCLUSIONS: Ocular Oncology multidisciplinary team, by sharing expertise of different specialists, ensures a comprehensive evaluation of patients improving the accuracy of diagnosis and staging upon which planning a proper treatment. Further studies are needed to assess if this approach may also improve the outcomes and prognosis of patients.

Clinical-Radiological Patterns and Histopathological Outcomes in Non-Thyroid Extraocular Muscle Enlargement: Retrospective Case Series and Current Concepts.

PURPOSE: To report a single-center experience with non-thyroid causes of extraocular muscle enlargement (EME), describing the association between clinical-radiological findings at presentation and the final histopathological diagnosis. METHODS: Retrospective consecutive case series of 59 patients with single or multiple EME on orbital imaging, in the absence of an etiological diagnosis at the time of presentation. All patients were submitted to orbital muscle biopsy in order to achieve a final etiological diagnosis. Patients with a confirmed diagnosis of thyroid-associated orbitopathy and vascular causes of EME which were angiographically and clinically diagnosed were excluded. Orbital ultrasound and radiologic evaluation (CT and/or MRI) were performed before surgery in all cases. Main outcomes measured included initial clinical-radiological findings and final histopathological features of EME. RESULTS: A diagnosis of lymphoma was confirmed in 13 cases (22%). Sixteen cases (27%) were diagnosed as orbital inflammatory disease including nonspecific idiopathic orbital inflammatory disease in 9 cases, IgG4-related disease in 4 cases, and sclerosing idiopathic orbital inflammatory disease in 3 cases. In 11 patients (18%), a diagnosis of metastatic tumor was made, whereas sarcoidosis, vascular malformations, Erdheim-Chester, and necrobiotic xanthogranuloma were diagnosed in 8 eyes (13.5%). Three patients (5%) with single muscle enlargement developed Graves disease 10 months later. Four patients (6.7%) were diagnosed with granulomatosis with polyangiitis. In 2 cases (3.3%), the diagnosis was unknown, with inconclusive biopsy results. Differential patterns for inflammatory/vascular, lymphomatous and metastatic EME were identified based on age and gender distribution and clinical-radiological characteristics at presentation. CONCLUSIONS: Initial clinical and radiological features may orientate the differential diagnosis of non-thyroid EME.

Pembrolizumab as first-line treatment for metastatic uveal melanoma.

BACKGROUND: No standard treatment has been defined for metastatic uveal melanoma (mUM). Although clinical trials testing Nivolumab/Pembrolizumab for cutaneous melanoma did not include mUM, anti PD-1 agents are commonly used for this disease. PATIENTS AND METHODS: In this prospective observational cohort single arm study, we investigated efficacy and safety of Pembrolizumab as first-line therapy for mUM. The efficacy was evaluated in terms of progression-free survival (PFS), response rate and overall survival (OS). Toxicity was also assessed. RESULTS: Seventeen patients were enrolled. A median of 8 cycles were administered (range 2-28). Two patients achieved partial response (11.7%), 6 a disease stabilization (35.3%), whereas 9 (53%) had a progression. No complete response was observed. PFS of the overall population was 3.8 months. PFS was 9.7 months for patients with an interval higher than 5 years from diagnosis of primary tumor to metastatic disease and 2.6 months for patients with an interval lower than 5 years [p = 0.039, HR 0.2865 (95% CI 0.0869-0.9443)]. Median OS was not reached. The two responding patients were still on treatment with Pembrolizumab at the time of data analysis. Survival was 12.8 months for patients with clinical benefit, while OS for progressive patients was 3.1 months. PD-L1 expression and genomic abnormalities predictive of relapse after diagnosis of primary tumor were not associated with PFS. Toxicity was mild, without grade 3-4 side effects. CONCLUSIONS: The efficacy of Pembrolizumab does not seem particularly different when compared to other agents for mUM, but responding patients had a remarkable disease control.

Uveal melanoma: evaluation of extrascleral extension using thin-section MR of the eye with surface coils.

PURPOSE: This study was done to evaluate the role of high-resolution magnetic resonance (MR) imaging with special surface coils in selecting the correct therapeutic approach (eye enucleation or follow-up) in patients with suspected extrascleral extension of uveal melanoma. MATERIALS AND METHODS: This prospective study involved 12 patients with suspected extrascleral extension of uveal melanoma on orbital ultrasonography. All patients were studied with thin-section MR imaging of the eye using surface coils. RESULTS: High-resolution MR imaging of the eye excluded extrascleral extension of disease in 8/12 patients: in 4/8 cases it revealed vascular ectasia and in the other 4/8 cases the linear hypointensity of the sclera was unbroken. Seven of these eight patients were followed up by ultrasound, which showed stability of melanoma for at least 2 years, while the last patient underwent enucleation, and the histological examination confirmed the MR diagnosis. In 4/12 patients, high-resolution MR suggested a diagnosis of extrascleral extension of melanoma, which was confirmed at histological examination after enucleation. CONCLUSION: High-resolution MR imaging of the eye with surface coils allowed us to evaluate extrascleral extension of uveal melanoma and choose the correct therapeutic approach, avoiding unnecessary enucleation in 7/12 patients.

Incidental Finding of Suprachoroidal Space's Silicone Oil Migration: A Tumor-Mimicking Lesion and Its Clinical Management.

The migration of silicone oil into the suprachoroidal region is a rare complication of vitrectomy. A 70-year-old man was admitted to our ocular oncology unit with a choroidal elevation in the nasal area, as well as signs of pars plana vitrectomy surgery performed about 5 years ago for retinal detachment. The patient underwent ocular ultrasound, visual field test, fluorangiography, and magnetic resonance imaging, which led to the diagnosis of silicone oil migration in the suprachoroidal space. Silicone oil may move into the suprachoroidal area, mimicking choroidal neoformation. It is important to have a comprehensive diagnosis and then set up the appropriate treatment. [Ophthalmic Surg Lasers Imaging Retina 2024;55:104-108.].

Management of Terson Syndrome: Long-Term Experience in a Single Center.

BACKGROUND/OBJECTIVES: Terson Syndrome (TS) is a rare entity consisting of an intraocular hemorrhage secondary to subarachnoid hemorrhage (SAH) or intracerebral hemorrhage (IH). This study aimed to retrospectively describe the experience of the Ophthalmology Unit of Policlinico Gemelli, Rome, in the management of TS. METHODS: Twenty-four eyes of 19 patients (10 males-53%; 9 females-47%; mean age of 44.73 ± 12.49 years) with TS who had pars plana vitrectomy between 2011 and 2024 were included. The primary outcome was the mean change in best-corrected visual acuity (BCVA) 1-3 months after surgery. The secondary outcome was the correlation of post-operative BCVA with the timing of vitrectomy (early vs. late, ≤100 or >100 days). RESULTS: The time between diagnosis and surgery ranged from 33 to 284 days (median = 102 days, interquartile range IQR = 74-161). Baseline BCVA ranged from 6 to 50 ETDRS letters with a median of 17 letters (IQR = 15-25) and significantly increased after surgery, with a median value of 80 (IQR = 70-85). The BCVA percentage improvement had a median of 325% (IQR = 300-431%). No differences in post-operative BCVA were found between patients who underwent early or late vitrectomy. One vitrectomy was complicated by an endophthalmitis. CONCLUSIONS: Although no clear guidelines exist on managing TS, vitrectomy significantly improves BCVA, and a delay in surgical intervention does not necessarily worsen the functional outcome. However, an early vitrectomy could improve the stimuli perception, facilitating the rehabilitation process.

Bilateral papilledema associated with retinal hemorrhagic appearance as earliest sign of spinal cord tumor.

INTRODUCTION: To report a case of a 57-years-old female patient who presented with prominent bilateral proptosis and swollen disks. CASE DESCRIPTION: A 57-year-old obese patient admitted to our ophthalmic department complaining of bilateral sense of eye swelling and mild blurring vision. The anterior segment and pupillary reflex were normal on ophthalmological testing. Likewise, eye movements were preserved and she did not report diplopia in any position of gaze. Dilated fundus examination revealed bilateral hemorrhagic papilledema, pre-retinal hemorrhages in both eyes, dot and blot hemorrhages in the peripheral retina. Visual acuity was 20/20 in both eyes. Routine hematological investigations revealed increased both Von Willebrand factor and ristocetin factor and LAC positivity. The lumbar puncture (LP) showed elevated cerebrospinal fluid (CSF) proteins. Magnetic resonance imaging (MRI) with contrast of brain and spinal cord showed signs of intracranial hypertension and the presence of two lesions in continuity with each other respectively located at T12-L1 and L1-L2. Radiologic features were compatible with the diagnosis of ependymoma. A surgical procedure was conducted and confirmed the diagnosis after anatomical pathology analysis. CONCLUSION: Although rare, bilateral hemorrhagic swollen disks could be an early sign of spinal cord tumors, in particular ependymomas.

Supportive treatment to chemotherapy with MMC, in patients with ocular surface squamous neoplasia or conjunctival melanocytic tumor.

PURPOSE: Since there is a lack of clear information regarding the benefit to combine supportive therapies (such as artificial tears) to mitomycin C (MMC) in the treatment of ocular surface neoplasia, the primary purpose of the study was to evaluate hyaluronic acid eye drops and hyaluronic acid-conjugated lactobionic acid (LACTOyal FREE) eye drops as supportive therapy. METHODS: Retrospective evaluation of patients with ocular surface squamous neoplasia or conjunctival melanocytic tumor treated with MMC, who had used also artificial tears as supportive treatment. A 6-month follow-up with evaluation of subjective and objective tests for ocular surface integrity was conducted. RESULTS: A total of 35 patients were analyzed, most of them with squamous disease (71.4%). The break-up time (BUT), Ocular Surface Disease Index (OSDI) and Schirmer test values showed a significant difference at any time point with overall population. No statistical difference was found among subgroups (Lactoyal vs No Lactoyal). CONCLUSION: The use of an ancillary therapy based on hyaluronic acid allows to improve both subjective and objective ocular parameters, reducing MMC induced adverse effects. Meantime, hyaluronic acid-conjugated lactobionic acid eye drops highlighted the same advantages with a more positive trend in OSDI results.

Photodynamic therapy (PDT) as adjuvant treatment to brachytherapy for amelanotic choroidal melanoma.

PURPOSE: To evaluate the effect of photodynamic therapy (PDT) as adjuvant treatment, after brachytherapy, in posterior amelanotic choroidal melanomas. METHODS: Six patients with posterior amelanotic choroidal melanoma underwent brachytherapy treatment. Tumour response was assessed by fundus examination, fundus photography and A-B scan ultrasonography. The residual tumours were treated with adjuvant PDT performed with infusion of verteporfin intravenously at 6 mg/m2 body surface area. Five minutes after infusion, a 689 nm laser was applied with a light dose of 100 J/cm2 over an interval of 166 s. RESULTS: At a median follow-up after brachytherapy of 17.5 months (IQR 16.2-22.5, range 5-42 months), tumours showed a partial reduction of tumour thickness (22.5% as compared to baseline value) and persistent low internal reflectivity at A-B scan ultrasonography. Supplementary photodynamic treatment resulted in complete resolution of the lesion with marked decrease of elevation . Mean decrease in thickness after PDT was 49.9% with respect to previous brachytherapy treatment 22.5% (p = 0.007). The results was achieved within a median period of 4 months (range 2-4 months) after PDT, and there has been no recurrence after a median follow-up of 84.7 months ± 18.7 (range 59 to 107 months). CONCLUSION: Combined treatment of brachytherapy and adjuvant PDT in amelanotic uveal melanoma seems to be favourable with regard to complete and rapid tumour regression.

Radiological and clinical findings in uveal melanoma treated by plaque interventional radiotherapy (brachytherapy): Visual atlas and literature review on response assessment.

Uveal melanoma (UM) is the most common intra-ocular tumor in Caucasian adults and may derive from melanocytes. Historically, the first therapeutic approach to treat UM has been surgical removal of the eye, with obvious consequences in terms of function, cosmesis, and psychological impact on patients. Collaborative Ocular Melanoma Study (COMS) introduced the first uniform approach to perform interventional radiotherapy (IRT - brachytherapy) procedure in a standardized way that allowed to demonstrate equivalence of IRT with enucleation in terms of overall survival. Since this milestone, several international guidelines have been issued with regard to several technical aspects of this procedure, which has become the mainstream therapy worldwide. However, nowadays, there is still a lack of consensus about the criteria to definitively assess UM response after IRT. We present a collection of paradigmatic cases treated in our institution, and then discuss in detail the latest available evidence on the topic.

Clinical and ultrasonographic features of choroidal metastases based on primary cancer site: Long-term experience in a single center.

INTRODUCTION AND PURPOSE: Choroidal metastases (CM) are the most common intraocular malignancies. With longer survival rates for cancer patients, CM will be increasingly encountered. We evaluated clinical and ultrasonographic (US) characteristics of CM in order to identify diagnostic biomarkers that correlate with the primary tumor site. METHODS: The medical records of all patients with CM evaluated at the Ocular Oncology Unit between February 2010 and March 2020 were analyzed. RESULTS: 82 eyes of 70 patients were included. The primary cancer site was lung in 26 patients (37%), breast in 23 (33%), kidney in 9 (13%), gastrointestinal in 5 (7%), thyroid in 5 (7%), parathyroids and prostate respectively in 2 (3%). Fifty-five patients (78%) had other systemic metastases at the time of ocular diagnosis. Ten (14%) patients had no history of primary cancer. Bilateral CM were found in 20 patients (29%); fifty-six eyes (68%) had a single CM. The epicenter of CM was predominantly macula (43 eyes, 52%). The mean thickness was 4,1 mm (range 1,8-12,3). US structure was inhomogeneous in 67 eyes (82%). Reflectivity was mainly medium (39%) and medium-low (39%). In particular, CM from lung cancer showed lower reflectivity than those from the breast (p = 0,02). CM deriving from lung cancer were typically dome-shaped, whereas CM originating from breast were characteristically plateau shaped (p = 0,02). Seventy-four (91%) eyes presented fluid on optical coherence tomography. CONCLUSION: We significatively found that CM from lung cancer generally appear dome-shaped with medium-low internal reflectivity, whereas those from breast cancer typically present a plateau appearance and higher internal reflectivity. Though it is hard to identify the site of the primary tumor relying exclusively on clinical and US aspects, morphology and internal reflectivity can be considered as diagnostic biomarkers. Thus, the origin of the primary tumor can be suspected by integrating a constellation of findings.

Retinal Morpho-Functional Changes Following 0.19 mg Fluocinolone Acetonide Intravitreal Implant for Chronic Diabetic Macular Edema.

PURPOSE: To evaluate morpho-functional outcomes of the intravitreal fluocinolone acetonide (FAc) implant. METHODS: Retrospective, observational, single-center study. Primary endpoint was the mean change in central macular thickness (CMT) from baseline to month 1-3. Secondary endpoints included mean CMT change from baseline to month 4-8 and 9-14 and mean best corrected visual acuity (BCVA), photopic negative response (PhNR) and b-wave of flash full-field electroretinogram (ERG) changes from baseline to month 1-3, 4-8, and 9-14. RESULTS: Fourteen patients (18 eyes) were included. Mean (standard deviation) CMT decreased from 473 (196) µm at baseline to 371 (163) µm at month 1-3 (mean difference - 102.3 ± 98.35 µm, 95% CI ± 46.4 µm; p < 0.0001) and this decrease tended to endure up to month 9-14. BCVA did not change significantly. There was an improvement in mean PhNR amplitude from 2.76 (1.65) µV at baseline to 3.73 (2.32) µV at month 1-3 (mean difference 0.91 (1.14) µV, 95% CI ± 0.54 µV, p = 0.003); b-wave amplitude improved from 8.83 (4.52) µV at baseline versus 10.05 (5.04) µV at month 1-3 (mean difference 1.22 (2.23) µV, 95% CI ± 1.08 µV, p = 0.0384). These ERG positive changes tended to endure up to month 9-14, although they did not reach statistical significance after month 3. CONCLUSIONS: Intravitreal FAc implant significantly improved anatomic as well as functional outcomes related to middle and inner retinal layers, known to be altered in diabetic retinopathy. Our findings support the hypothesis that intravitreal FAc implant may exert a protective effect in diabetic retinas with diabetic macular edema.

Choriocapillaris Vascular Density Changes: Healthy vs. Advanced Exudative Age-Related Macular Degeneration Previously Treated with Multiple Anti-VEGF Intravitreal Injections.

PURPOSE: To assess choriocapillaris vascular density (VD) in healthy and advanced exudative age-related macular degeneration (ae-AMD) patients by new full-range optical coherence tomography angiography (OCT-A). METHOD: In this observational, cross-sectional study, 21 healthy and 21 ae-AMD eyes, already treated with anti-VEGF, were enrolled. Angio-View retina patterns centered on fovea (6.4 × 6.4 mm) were acquired for all participants using Solix full-range OCT (Optovue Inc., Freemont, CA, USA). The main outcome was to compare choriocapillaris VD between healthy and ae-AMD eyes. Automated measurements of whole image choriocapillaris VD (%) and fovea grid-based (%) were collected for the analysis. Angio-View patterns were used to assess the flow area (mm2) of macular neovascularization (MNV) by contour flow measure algorithm. Best-corrected visual acuity (BCVA) of both groups was also used for the statistical analysis. RESULTS: The mean age was 60.9 (±8.3) in healthy and 73.33 (±15.05) in ae-AMD eyes. The mean BCVA (ETDRS letters) was 98.47 (±1.50) in healthy and 7.04 (±5.96) in ae-AMD eyes. The Mann-Whitney test comparing choriocapillaries VD for whole and fovea healthy and ae-AMD eyes showed statistical significance (p < 0.0001 (t = 4.91; df = 40) and p < 0.0001 (t = 6.84; df = 40), respectively). Regarding, the correlation between MNV and VD of choriocapillaries, neither whole nor fovea areas were statistically significant (F = 0.38 (R2 = 0.01) and 1.68 (R2 = 0.08), respectively). CONCLUSIONS: Choriocapillaris VD showed a statistically significant reduction in comparison to healthy eyes in ae-AMD eyes. Choriocapillaris impairment can be seen in the early phase of MNV pathogenesis.

Short-Term Assessment of Intravitreal Dexamethasone Implant Using Enhanced-Depth Image Optical Coherence Tomography and Optical Coherence Tomography Angiography in Patients with Retinal Vascular Diseases.

INTRODUCTION: To evaluate the short-term efficacy and safety of intravitreal dexamethasone implant (IDI) in patients with macular oedema associated with diabetic retinopathy (DR) and retinal vein occlusion (RVO) using enhanced-depth image optical coherence tomography (EDI-OCT) and to estimate the effect of dexamethasone on the choroid and the retinal vascular network using OCT angiography (OCTA). METHODS: Fifteen eyes in 15 patients with macular oedema secondary to diabetes (DR, n = 8) or retinal vein occlusion (RVO, n = 7) were treated with intravitreal injection of sustained-release IDI. Primary efficacy end points were changes in best corrected visual acuity and central macular thickness (CMT). Secondary end points were changes in choroidal thickness and choroidal and retinal vascular networks as determined by OCTA. RESULTS: CMT was significantly reduced from baseline by 3 h after injection (p < 0.01) and improved further during the 3-month follow-up. Visual acuity improvement was consistent with CMT reduction. No alterations in IOP or systemic side effects were observed. OCTA showed improvement from baseline in terms of decreased number and size of cysts and restoration of the retinal vascular network; flow choroidal thickness did not change significantly. CMT and visual acuity variations were similar in the two groups. CONCLUSIONS: CMT reduced as early as 3 h after the injection of IDI, with further reduction during follow-up. Choroidal thickness was unchanged, whereas the vascular retinal network improved from baseline to the end of study. Both EDI-OCT and OCTA were useful in demonstrating the early beneficial effects of IDI on the macula and the perifoveal vascular network. FUNDING: The article processing charges, the open access fee and the medical writing and editorial assistance was funded by Allergan.

Personalized re-treatment strategy for uveal melanoma local recurrences after interventional radiotherapy (brachytherapy): single institution experience and systematic literature review.

PURPOSE: To report the results of a patient's tailored therapeutic approach using a second course of interventional radiotherapy (brachytherapy) in patients with locally recurrent uveal melanoma. MATERIAL AND METHODS: Patients who had already undergone ocular brachytherapy treated at our IOC (Interventional Oncology Center) were considered. Five patients who has received a second course of treatment with a plaque after local recurrences were included in our study. Re-irradiation was performed with Ruthenium-106 (prescribed dose to the apex 100 Gy) or with Iodine-125 plaques (prescribed dose to the apex 85 Gy). Moreover, a systematic literature search was conducted through three electronic databases, including Medline/PubMed, Scopus, and Embase. RESULTS: All patients were initially treated with Ruthenium-106 plaque; the re-irradiation was performed with Ruthenium-106 plaque in three cases and with Iodine in two cases. Mean time between the first and the second plaque was 56.8 months (range, 25-93 months). Local tumor control rate was 100%, no patient underwent secondary enucleation owing to re-treatment failure. Distant metastasis occurred in 1 patient after 6 months from re-treatment. After a median follow-up of 44.2 months (range, 26-65 months) from re-treatment, all patients experienced worsening of the visual acuity (median visual acuity was 0.42 at time of recurrence and decline to 0.24 at the most recent follow-up); cataract occurred in two cases, no patient developed scleral necrosis. We considered 2 papers for a systematic review. CONCLUSIONS: In selected cases, especially in presence of marginal local recurrence, a personalized re-treatment strategy with a plaque may offer high probability of tumor control and organ preservation but worsening of visual acuity.

Photodynamic Therapy in Ocular Oncology.

Although introduced for the treatment of maculopathies, photodynamic therapy (PDT) is now largely used in some eye cancers treatment. The selective tissue damage with PDT is achieved by sequestration of the photosensitizer in the target tissue and focal activation of the photosensitizer by low energy directed light. In this way, it is possible to achieve the destruction of the tumor tissue by safeguarding the surrounding healthy structures. Our study describes the clinical uses and efficacy of photodynamic therapy in ocular oncology.

INTERACTS (INTErventional Radiotherapy ACtive Teaching School) guidelines for quality assurance in choroidal melanoma interventional radiotherapy (brachytherapy) procedures.

Eye plaque brachytherapy represents a safe and effective therapeutic approach for choroidal melanoma, combining clinical outcomes with an eye and visual preservation. As it represents a complex procedure, a specific quality assurance program is strongly suggested to improve patients and operators safety, and to reduce possible complications linked to surgical procedure and radiation exposure. The aim of this paper is to describe the INTERACTS (Interventional Radiotherapy Active Teaching School) guidelines for quality assurance in choroidal melanoma interventional radiotherapy (brachytherapy) used in our institution.

Underestimate of tonometric readings after photorefractive keratectomy increases at higher intraocular pressure levels.

PURPOSE: To determine whether tonometric readings of increases in intraocular pressure (IOP) during the water-drinking test (WDT) are affected by variations in central corneal thickness (CCT) induced by photorefractive keratectomy (PRK). METHODS: Data from 30 randomly selected eyes of 30 patients (18 men and 12 women; mean age, +/- SD: 33.9 +/- 7.6 years) undergoing bilateral PRK for myopia (-6.57 +/- 2.39 D) were obtained. Objective refraction, anterior radius of corneal curvature (R), CCT, and IOP measurements at baseline and at different time intervals after ingestion of 1 L of water within 5 minutes, were performed before and 6 months after PRK. All measured IOPs were recalculated by a correction factor for R and CCT and expressed as corrected intraocular pressure (IOPC) measurements. RESULTS: The mean R +/- SD was 7.84 +/- 0.20 and 8.76 +/- 0.34 mm, and the mean CCT was 544.83 +/- 19.69 and 453.97 +/- 29.95 microm, before and after PRK, respectively. The mean IOP at baseline was 15.05 +/- 2.78 and 9.83 +/- 2.56 mm Hg, and during WDT was 18.32 +/- 3.42 and 11.42 +/- 3.10 mm Hg at 10 minutes, 18.59 +/- 2.99 and 11.54 +/- 2.54 mm Hg at 20 minutes, 17.80 +/- 2.85 and 10.87 +/- 2.22 mm Hg at 30 minutes, 16.35 +/- 3.02 and 10.26 +/- 2.21 mm Hg at 45 minutes, and 14.90 +/- 2.52 and 9.81 +/- 2.32 mm Hg at 60 minutes, before and after PRK, respectively. The mean IOPC at baseline was 13.64 +/- 2.33 and 13.05 +/- 2.98 mm Hg, and during WDT was 16.61 +/- 2.77 and 15.08 +/- 3.59 mm Hg at 10 minutes, 16.96 +/- 2.69 and 15.33 +/- 2.96 mm Hg at 20 minutes, 16.10 +/- 2.50 and 14.42 +/- 2.60 mm Hg at 30 minutes, 14.92 +/- 2.72 and 13.62 +/- 2.65 mm Hg at 45 minutes, 13.82 +/- 2.27 and 13.05 +/- 2.55 mm Hg at 60 minutes, before and after excimer laser treatment, respectively. Pre- and postoperative IOPs and percentages of IOP increase differed significantly (P < 0.05), in particular at the peak, as did IOPCs but not the percentages of increase in IOPC, apart from the highest values. CONCLUSIONS: Corneal changes after PRK for myopia may induce an uneven underestimate of the IOP increases. The inadequacy of a correction factor to compensate for CCT and R at high IOP levels indicates that other biomechanical factors may play a role when the cornea is subjected to dynamic actual IOP variation. Such increase of the well-known underestimate of IOP after PRK at higher actual IOPs may have significant clinical implications in tonometric assessment of subjects at risk of glaucomatous damage.

Tonometric changes of latanoprost-induced intraocular pressure reduction after photorefractive keratectomy.

PURPOSE: To assess whether tonometric measurements of the drop in intraocular pressure (IOP) induced by 0.005% latanoprost are modified after photorefractive keratectomy (PRK). METHODS: Data from 24 randomly selected eyes of 24 patients (12 men and 12 women, mean age +/- SD: 31.7 +/- 6.2 years) who were undergoing bilateral PRK for myopia (-6.38 +/- 2.26 D) were obtained. Objective refraction, central corneal thickness (CCT), anterior radius of corneal curvature (R), and IOP measurements at baseline and 24 hours after 1 drop of 0.005% latanoprost, were performed before and 6 months after PRK. All measured IOPs were recalculated by a correction factor for CCT and R and expressed as true IOP (IOPT) measurements. RESULTS: The mean CCT +/- SD was 544.58 +/- 36.03 and 463.21 +/- 38.59 micro m, and the anterior radius of corneal curvature was 7.73 +/- 0.26 and 8.33 +/- 0.37 mm, before and after PRK, respectively. The mean IOP at baseline was 15.8 +/- 2.92 and 12.23 +/- 2.37 mm Hg, and after latanoprost administration was 12.54 +/- 1.97 and 10.19 +/- 1.47 mm Hg, before and after PRK, respectively. The mean IOPT at baseline was 15.46 +/- 1.08 and 16.18 +/- 2.31 mm Hg, and after latanoprost administration was 11.85 +/- 1.56 and 12.96 +/- 1.71 mm Hg, before and after PRK, respectively. The mean IOP and IOPT reductions after latanoprost administration were, respectively, 3.25 +/- 1.66 and 3.61 +/- 1.7 mm Hg before PRK, and 2.03 +/- 1.42 and 3.22 +/- 1.79 mm Hg after PRK. Pre- and postoperative IOP reduction significantly differed (P < 0.001), but not IOPT. CONCLUSIONS: The effect of hypotensive drugs on IOP readings may be underestimated because of measurement errors due to CCT reduction and R increase after PRK for myopia. Misdiagnosis of reduced pharmacologic efficacy may be avoided if the measured IOP is corrected by a proper nomogram.