Henle Fiber Layer Research Articles

PARACENTRAL ACUTE MIDDLE MACULOPATHY AND HENLE FIBER LAYER HEMORRHAGE IN DENGUE FEVER: MULTIMODAL IMAGING AND REVIEW OF THE LITERATURE.

To use multimodal imaging to report a case of dengue fever presenting with Henle fiber layer hemorrhage (HH) and acute paracentral acute middle maculopathy (PAMM). Fundus photography and autofluorescence, fluorescein angiography, and optical coherence tomography (OCT) were acquired over a month, and a literature review of dengue fever-associated maculopathy was performed. A 19-year-old man presented with a sudden loss of vision in both eyes 12 days after experiencing initial systemic symptoms suggestive of dengue fever. His best-corrected visual acuity (BCVA) was counting fingers in the right eye (OD) and 20/200 in the left eye (OS). Pupillary light reflex was reduced in both eyes (OU). Dilated fundoscopic examination revealed optic disc swelling and a small deep hemorrhage near the fovea in OU. OCT revealed a petaloid shape hyperreflectivity involving both outer nuclear and plexiform layers in OU and a subtle hyperreflectivity thinning the inner nuclear layer (INL) in OS, findings compatible with HH and PAMM, respectively. Immunoglobin M was positive for dengue fever. Thus, a diagnosis of dengue fever-associated maculopathy was performed and oral steroids were started. After a month, the final BCVA reached 20/25 (OD) and 20/20 (OS), the HH reabsorbed utterly, and a INL thinning in the area of the PAAM was observed. Dengue fever-associated maculopathy can present with PAAM and HH. Multimodal imaging is helpful to characterize the extension of the changes in the retina and to monitor its recovery. In such cases, structural and functional damage may occur despite treatment with oral steroids.

Analysis of Henle's fiber layer and outer retinal layers in cone dystrophy.

To evaluate Henle's Fiber Layer (HFL) thickness and volume parameters in patients with cone photoreceptor atrophy with directional optical coherence tomography (D-OCT). Macular 20°×20° standard and D-OCT images were acquired from patients diagnosed with hereditary cone dystrophy with evident foveal ellipsoid zone defect in OCT, and age-matched healthy controls. Thickness and volume parameters of HFL, outer nuclear layer (ONL) and retinal layers between ellipsoid zone and Bruch membrane complex (EZ-BM) were calculated from manual segmentation through D-OCT images and comparative analysis is performed. Twelve eyes of 6 patients were compared to 12 eyes of 6 age-matched healthy controls (mean age: 29.5±16.6 and 26.6±3.9 years respectively; P=0.162). Patients had lower total HFL volume (0.45±0.03 and 0.85±0.15 mm3; P<0.001) and mean HFL thickness (16.1±1.1 and 30.1±5.3 µm; P<0.001) than healthy controls. Central subfield, parafoveal and perifoveal ETDRS zone HFL parameters in patients were significantly lower than healthy controls. A centrifugal correlation was found between central ONL and the corresponding parafoveal HFL (Spearman's rho: 0.785; P<0.001). HFL assessment might be a useful OCT biomarker in patients with cone photoreceptor atrophy. HFL thinning is observed in foveal, parafoveal and perifoveal areas of patients with cone photoreceptor atrophy, while volume reduction in ONL and EZ-BM components were limited to central and parafoveal zones.

ACUTE POSTERIOR MULTIFOCAL PLACOID PIGMENT EPITHELIOPATHY AND PLACOID VARIANT DISEASES MASQUERADING AS AGE-RELATED MACULAR DEGENERATION IN THE ELDERLY: A Case Series.

To report eight cases of acute posterior multifocal placoid pigment epitheliopathy (APMPPE) or persistent placoid maculopathy (PPM) initially masquerading as age-related macular degeneration in elderly individuals. APMPPE or PPM eyes in patients above age 55 years with macular retinal pigment epithelium disruption including drusenoid lesions on macular examination and/or with multimodal imaging were included. At least one method of multimodal imaging including fluorescein angiography (FA), indocyanine green angiography, optical coherence tomography (OCT), and OCT angiography (OCTA) was performed in all eyes for diagnosis and to monitor for macular neovascularization. Eight elderly male patients presented with vision loss and were all initially diagnosed with non-neovascular or neovascular age-related macular degeneration. With the aid of multimodal retinal imaging, a final diagnosis of either APMPPE or PPM was rendered. With FA and indocyanine green angiography, choroidal hypoperfusion was detected in all but one eye. With OCT, the angular sign of Henle fiber layer hyperreflectivity was identified in >50% of eyes. With OCTA, inner choroidal flow deficits were detected in all eyes. Macular neovascularization requiring anti-vascular endothelial growth factor injection therapy complicated three of eight cases. Both APMPPE and PPM may develop in elderly individuals and may masquerade as age-related macular degeneration on presentation. Multimodal imaging including FA, indocyanine green angiography, and OCTA are important diagnostic modalities to assess for inner choroidal hypoperfusion to arrive at an accurate diagnosis and to detect macular neovascularization, which frequently complicates APMPPE and PPM. In these patients, serial anti-vascular endothelial growth factor intravitreal injections are essential in treating macular neovascularization and in preventing significant vision loss.

Spectrum of retinal microvascular ischemia in patients with COVID-19 based on multimodal imaging

PurposeTo describe and evaluate the multimodal imaging findings in retinal microvascular ischemia associated with COVID-19 infection. MethodsPatients with COVID-19 associated retinal microvascular ischemia and visiting the outpatient Department of Ophthalmology, Shanghai General Hospital from December 2022, to February 2023, were documented and their multimodal images were retrospectively reviewed. Retinal microvascular ischemia was defined as the presence of isolated or multiple focal retinal whitening(s) on color fundus images. Patients with retinal vessel occlusion or retinopathies secondary to systematic disorders diagnosed before infection were excluded. ResultsA total of 32 eyes from 21 patients were included, 24 (75.00 %) eyes with multiple retinal whitenings, while 8 (25.00 %) eyes with isolated lesions. When divided by the types of ischemia, 9 (28.13 %) eyes had only inner retinal involvement (known as cotton wool spot, CWS), 4 (12.50 %) eyes had only middle retinal involvement (known as paracentral acute middle maculopathy, PAMM), and 19 (59.38 %) eyes had both. In addition, 4 (12.50 %) eyes had coincident angular sign of Henle fiber layer hyperreflectivity (ASHH). Patients with hypertension tended to have multiple lesions rather than isolated lesion of retinal microvascular ischemia (P = 0.008). Transient uncontrolled high blood pressure or acute kidney injury was simultaneously detected in some cases. ConclusionsOcular manifestation of COVID-19 associated microvascular ischemia can be variable, including CWS, PAMM and ASHH. Multimodal fundus imaging technologies are useful tools to reveal involved retinal layers, extent, and severity. Moreover, ocular manifestations may serve as a window of COVID-19 related microcirculation in other systems throughout the body.

EN FACE OPTICAL COHERENCE TOMOGRAPHY MORPHOLOGY OF MACULAR PUCKER CORRELATES WITH METAMORPHOPSIA: Possible Role of the Henle Fiber Layer.

To describe macular pucker contraction patterns with en face optical coherence tomography (OCT), to provide a correlation with metamorphopsia scores, and to discuss the protective role of the Henle fiber layer (HFL) against tangential traction. Retrospective, institutional, observational, and consecutive case series. Clinical charts, M-charts scores, and structural and en face OCT imaging of patients diagnosed with macular pucker were reviewed. A 120 eyes of 114 consecutive patients diagnosed with macular pucker were included. En face OCT patterns of macular pucker contraction were foveal in 51 of 120 eyes (42.5%) and extrafoveal in 69 of 120 eyes (57.5%). Foveal macular puckers had regular, a concentric, circle morphology in the HFL (46/51 eyes, 90.2%), whereas extrafoveal membranes had irregular, distorted, circular HFL morphology (62/69 eyes, 89.8%; P < 0.001). Foveal contraction morphology and regular HFL pattern, as well as extrafoveal contraction morphology and an irregular HFL pattern, highly correlated one with another (P < 0.001 in both cases). Foveal macular puckers with regular HFL patterns had significantly less vertical and horizontal M-charts scores as compared with extrafoveal membranes with irregular HFL (P < 0.001 in both cases). Ellipsoid zone and external limiting membrane defects were rare in the parafoveal region (5/120 eyes, 4.2%). Visual acuity did not correlate with metamorphopsia scores (P = 0.903). En face OCT imaging identifies macular pucker contraction patterns that correlate with metamorphopsia scores and that can be used alongside the current structural OCT staging system to guide clinicians in the surgical decision-making process.

THE PROGNOSTIC SIGNIFICANCE OF ACUTE HENLE FIBER LAYER HYPERREFLECTIVITY IN PLACOID DISEASES.

To investigate the pathophysiology and prognostic significance of acute Henle fiber layer (HFL) hyperreflectivity in placoid diseases by examining its relationship with impaired choroidal flow and persistent photoreceptor disruption. Retrospective-prospective observational study on patients with placoid diseases. Indocyanine green angiography and optical coherence tomography were performed during the acute phase and follow-up. Impaired choroidal flow, HFL hyperreflectivity, and persistent ellipsoid zone disruption, their colocalization index, and their associations with initial and final visual acuity were explored. Sixteen eyes from eight patients (mean age, 25.3 ± 6.44 years) were included (median follow-up, 13.5 months). Quantitative analysis revealed significant correlations between areas of impaired choroidal flow, HFL hyperreflectivity, and persistent ellipsoid zone disruption (correlation coefficients of 0.69, 0.63, and 0.46, respectively). Impaired choroidal flow area exceeded HFL hyperreflectivity (P = 0.002) and ellipsoid zone disruption (P = 0.003). A noteworthy 94% nonrandom overlap between HFL hyperreflectivity and ellipsoid zone disruption was observed. Worse initial visual acuity correlated with foveal involvement (P = 0.0002), thicker choroid (P = 0.001), larger impaired choroidal flow areas (P = 0.02), and thinner outer retina post lesion inactivation (P = 0.04). Henle fiber layer hyperreflectivity predicted photoreceptor recovery potential in placoid diseases. If HFL hyperreflectivity corresponds to acute HFL damage, it may suggest more severe involvement of the entire photoreceptor length.

High-throughput ultrastructural analysis of macular telangiectasia type 2.

Macular Telangiectasia type 2 (MacTel), is an uncommon form of late-onset, slowly-progressive macular degeneration. Associated with regional Müller glial cell loss in the retina and the amino acid serine synthesized by Müller cells, the disease is functionally confined to a central retinal region - the MacTel zone. We have used high-throughput multi-resolution electron microscopy techniques, optimized for disease analysis, to study the retinas from two women, mother and daughter, aged 79 and 48 years respectively, suffering from MacTel. In both eyes, the principal observations made were changes specific to mitochondrial structure both outside and within the MacTel zone in all retinal cell types, with the exception of those in the retinal pigment epithelium (RPE). The lesion areas, which are a hallmark of MacTel, extend from Bruch's membrane and the choriocapillaris, through all depths of the retina, and include cells from the RPE, retinal vascular elements, and extensive hypertrophic basement membrane material. Where the Müller glial cells are lost, we have identified a significant population of microglial cells, exclusively within the Henle fiber layer, which appear to ensheathe the Henle fibers, similar to that seen normally by Müller cells. Since Müller cells synthesize retinal serine, whereas retinal neurons do not, we propose that serine deficiency, required for normal mitochondrial function, may relate to mitochondrial changes that underlie the development of MacTel. With mitochondrial changes occurring retina-wide, the question remains as to why the Müller cells are uniquely susceptible within the MacTel zone.

Evaluating fingerprint-like patterns in the healthy Henle fiber layer using enface OCT imaging

PurposeEnface OCT may disclose a distinct “fingerprint-like' pattern within the HFL in various macular disorders. This study aims to investigate the frequency and characteristics of this pattern in healthy eyes and identify potential factors influencing its visibility. MethodsTwo, independent masked reading center graders evaluated for the presence and prominence of a fingerprint pattern in the Henle fiber layer (HFL) on enface OCT images from 33 healthy subjects (66 eyes). The prominence of the pattern was rated qualitatively using a 0–3 scale, with 3 indicating the strongest prominence. Tilt angles (relative to the normal/perpendicular at the center) of the retina were measured on horizontal and vertical B-scans, and the retinal curvature was assessed using ImageJ, in order to determine the impact of the incident light angle on the visibility and prominence of the fingerprint pattern. Inter-grader agreement using Cohen's kappa and the frequency and percentage of patterns in the entire enface image and in each quadrant were calculated and compared using the Friedman test with Dunn's post-test. A generalized estimating equation (GEE) was used to analyze the association between these metrics and fingerprint prominence. ResultsSubstantial inter-grader agreement was observed (Cohen's kappa = 0.71) for assessing the prominence of the fingerprint pattern. Over 70% of eyes exhibited some evidence of the pattern (score ≥1). Significant difference in pattern prominence across quadrants was detected (p < 0.05), with lowest prominence in the temporal quadrant (p < 0.001 for pairwise comparisons against all other quadrants). The GEE analysis to account for the extent of the effect of scan tilt angle and RPE curvature was not able to predict the prominence of the fingerprint pattern, highlighting that angle of incidence (of the scanning laser light) alone could not explain the pattern. ConclusionsThis study confirms that a fingerprint-like pattern within the HFL can also be observed in healthy eyes, challenging the notion that this finding is only manifest in the setting of disease. In addition, the lack of correlation with angle of incident light suggests that the pattern may be related to other intrinsic characteristics of the HFL.

Impact of Solar Eclipses on Vision: Insights from Optical Coherence Tomography and Optical Coherence Tomography Angiography Analysis*

Purpose Solar retinopathy, resulting from solar eclipse exposure, poses risks to visual health. This study explores acute and chronic phase findings using clinical examinations and optical coherence tomography (OCT) and optical coherence tomography angiography (OCT-A) with a focus on longitudinal assessment. Methods Seven eyes with a history of unprotected solar eclipse exposure were included. Clinical examination, fundus photography, OCT, and OCT-A imaging were performed at initial assessment, as well as at one-month and six-month follow-up intervals. Data analysis included descriptive statistics. Results The cases, exposed without protection, underwent assessments, revealing variable visual acuity, outer retinal layer, and Henle fiber layer changes during follow-up. Regression of hyperreflectivity within the outer retinal and Henle fiber layers was observed over time in all eyes, although persistent microdefects within the outer retinal layer were noted in specific cases. OCT-A imaging revealed a larger foveal avascular zone, which persisted over a six-month period in select cases. Additionally, affected eyes exhibited a decrease in superficial vascular density, with subsequent improvement noted during the six-month period. Conclusion Solar retinopathy can result in visual impairment, accompanied by alterations observed in the Henle fiber layer using OCT. Additionally, OCT-A findings indicate possible vascular involvement. This study underscores the significance of adopting protective measures during solar eclipses and emphasizes the value of employing longitudinal multimodal imaging techniques to comprehend the pathophysiology of the condition.

DIRECTIONAL OPTICAL COHERENCE TOMOGRAPHY IMAGING OF MACULAR PATHOLOGY.

To survey the impact of directional reflectivity on structures within optical coherence tomography images in retinal pathology. Sets of commercial optical coherence tomography images taken from multiple pupil positions were analyzed. These directional optical coherence tomography sets revealed directionally reflective structures within the retina. After ensuring sufficient image quality, resulting hybrid and composite images were characterized by assessing the Henle fiber layer, outer nuclear layer, ellipsoid zone, and interdigitation zone. Additionally, hybrid images were reviewed for novel directionally reflective pathological features. Cross-sectional directional optical coherence tomography image sets were obtained in 75 eyes of 58 patients having a broad range of retinal pathologies. All cases showed improved visualization of the outer nuclear layer/Henle fiber layer interface, and outer nuclear layer thinning was, therefore, more apparent in several cases. The ellipsoid zone and interdigitation zone also demonstrated attenuation where a geometric impact of underlying pathology affected their orientation. Misdirected photoreceptors were also noted as a consistent direction-dependent change in ellipsoid zone reflectivity between regions of normal and absent ellipsoid zone. Directional optical coherence tomography enhances the understanding of retinal anatomy and pathology. This optical contrast yields more accurate identification of retinal structures and possible imaging biomarkers for photoreceptor-related pathology.

CONCENTRIC MACULAR RINGS SIGN IN COMBINED HAMARTOMA OF RETINA AND RETINAL PIGMENT EPITHELIUM.

To describe two cases of concentric macular rings (CMR) sign in patients with combined hamartoma of retina and retinal pigment epithelium (CHRRPE). History and clinical examination, spectral-domain optical coherence tomography (SD-OCT), and optic coherence tomography angiography (OCTA). The first patient was a 26-year-old woman with clinical diagnosis of Neurofibromatosis type 2. The Best-Corrected Visual Acuity (BCVA) was 20/25 in the right eye (OD) and 20/20 in the left eye (OS). She presented a subtle grayish lesion in the macular region of OD. On macular SD-OCT, there was a thickened and disorganized retina, suggestive of CHRRPE. In addition, at the parafoveal region, there was a dentate pattern in the outer plexiform layer (OPL) and Henle fiber layer (HFL) on cross-sectional SD-OCT. OCTA showed no foveal avascular zone (FAZ) in OD and Optos ultra-wide-field revealed CMR sign in this eye. The second patient was a 14-year-old boy, with diabetes mellitus type 1. His BCVA was 20/25 in OD and 20/20 in OS. He had a subtle whitish lesion in the macular region of OD, with SD-OCT findings suggestive of CHRRPE. Similar to the first case, there was a dentate pattern in the OPL and HFL, on SD-OCT. In OD, blue reflectance images exhibited the CMR sign, and OCTA showed absent FAZ. CHRRPE may be related to changes in the OPL and HFL interface and may present the CMR sign.

Hemorrhagic unilateral retinopathy: a report of multimodal imaging in three cases.

To report three cases of hemorrhagic unilateral retinopathy, diagnosed by multimodal imaging. Case report of 3 patients, 2 women and one man, aged 51, 74, and 52, respectively. Symptoms were acute floaters, blurred vision, or central scotoma, unilateral in all cases. The best-corrected visual acuity was 20/20 in the affected eye in 2 patients with a paracentral scotoma, and 20/160 in the third patient. Funduscopic examination revealed multiple unilateral posterior hemorrhages located in the Henle fiber layer in the macula and beneath the internal limiting membrane around the optic disc on spectral-domain optical coherence tomography (SD-OCT). Fluorescein angiography and indocyanine green angiography (ICGA) did not show any vascular abnormalities. SD-OCT angiography (SD-OCT-A) did not show any capillary drop-out or choroidal abnormalities. In all patients, the visual symptoms completely disappeared within a few weeks, with spontaneous regression of the hemorrhages. Hemorrhagic unilateral retinopathy is a rarely reported and poorly understood disorder. ICGA and SD-OCT-A did not allow better understanding the condition. No etiology has been associated with this entity so far. The spontaneous resolution of the present cases confirmed the favorable visual prognosis of the condition.

Henle fiber layer thickening and deficits in objective retinal function in participants with a history of multiple traumatic brain injuries.

This study tested whether multiple traumatic brain injuries (TBIs) alter the structure of the Henle fiber layer (HFL) and degrade cell-specific function in the retinas of human participants. A cohort of case participants with multiple TBIs and a cohort of pair-matched control participants were prospectively recruited. Directional optical coherence tomography and scanning laser polarimetry measured HFL thickness and phase retardation, respectively. Full-field flash electroretinography (fERG) assessed retinal function under light-adapted (LA) 3.0, LA 30 Hz, dark-adapted (DA) 0.01, DA 3.0, and DA 10 conditions. Retinal imaging and fERG outcomes were averaged between both eyes, and paired t-tests or Wilcoxon signed-rank tests analyzed inter-cohort differences. Global HFL thickness was significantly (p = 0.02) greater in cases (8.4 ± 0.9 pixels) than in controls (7.7 ± 1.1 pixels). There was no statistically significant difference (p = 0.91) between the cohorts for global HFL phase retardation. For fERG, LA 3.0 a-wave amplitude was significantly reduced (p = 0.02) in cases (23.5 ± 4.2 μV) compared to controls (29.0 ± 8.0 μV). There were no other statistically significant fERG outcomes between the cohorts. In summary, the HFL thickens after multiple TBIs, but phase retardation remains unaltered in the macula. Multiple TBIs may also impair retinal function, indicated by a reduction in a-wave amplitude. These results support the potential of the retina as a site to detect TBI-associated pathology.

Henle fiber layer hemorrhage after seizure and its pattern of resolution

Henle fiber layer hemorrhage after seizure and its pattern of resolution

Unusual morphology of foveal Müller glia in an adult human born pre-term.

The fovea of the human retina, a specialization for acute and color vision, features a high concentration of cone photoreceptors. A pit on the inner retinal aspect is created by the centrifugal migration of post-receptoral neurons. Foveal cells are specified early in fetal life, but the fovea reaches its final configuration postnatally. Pre-term birth retards migration resulting in a small pit, a small avascular zone, and nearly continuous inner retinal layers. To explore the involvement of Müller glia, we used serial-section electron microscopic reconstructions to examine the morphology and neural contacts of Müller glia contacting a single foveal cone in a 28-year-old male organ donor born at 28 weeks of gestation. A small non-descript foveal avascular zone contained massed glial processes that included a novel class of 'inner' Müller glia. Similar to classic 'outer' Müller glia that span the retina, inner Müller glia have bodies in the inner nuclear layer (INL). These cells are densely packed with intermediate filaments and insert processes between neurons. Unlike 'outer' Müller glia, 'inner' Müller glia do not reach the external limiting membrane but instead terminate at the outer plexiform layer. One completely reconstructed inner cell ensheathed cone pedicles and a cone-driven circuit of midget bipolar and ganglion cells. Inner Müller glia outnumber foveal cones by 1.8-fold in the outer nuclear layer (221,448 vs. 123,026 cells/mm2). Cell bodies of inner Müller glia outnumber those of outer Müller glia by 1.7-fold in the INL (41,872 vs. 24,631 cells/ mm2). Müller glia account for 95 and 80% of the volume of the foveal floor and Henle fiber layer, respectively. Determining whether inner cells are anomalies solely resulting from retarded lateral migration of inner retinal neurons in pre-term birth requires further research.

Multimodal imaging of acute fovealitis with angular sign of Henle fiber layer hyperreflectivity (ASHH): Report of a case and review of the literature

Acute retinal pigment epitheliitis (ARPE) is a rare and transient macular disorder that was first described by Krill and Deutman in 1972. Later, Gerardo Ledesma-Gil and Spaide described a novel disease named acute fovealitis in 2022. According to them, this entity was different from ARPE on the basis of distinct features found in high-resolution optical coherence tomography (OCT) imaging. Angular sign of Henle fiber layer hyperreflectivity (ASHH) is a newly described terminology that is caused by an acute insult to photoreceptor compartments. In this article, we report a case that has both the ophthalmoscopic and OCT features of acute fovealitis as described in the literature, with the presence of ASHH in the acute stage, which resolves on its own rapidly along with the symptoms without any intervention.

Multimodal topographically oriented approach to the study of full-thickness macular holes

This article studies the relationship between structural changes according to the findings of optical coherence tomography (OCT) and OCT angiography (OCTA), microperimetry (MP), multifocal electroretinography (mfERG) parameters in topographically corresponding areas of the macular region in idiopathic full-thickness macular holes (FTMH). OCT, OCTA, MP and mfERG were performed in 14 eyes with FTMH stages I-IV according to Gass. In 13 points at a distance of 0-2.5°, 2.5-5.0°, and 5.0-10.0° from the fixation point, the light sensitivity (LS), amplitude and latency of the P1 component were compared with the size of the hole, the area of cystic changes (CC) at the level of the inner nuclear layer (INL) and the outer plexiform layer and Henle fiber layer complex (OPL+HFL), vessel density in the superficial and deep capillary plexus (SCP and DCP). LS and P1 component amplitude were significantly reduced at a distance of up to 5.0° from the fixation point. LS correlates with the apical and basal diameter of the hole (R> -0.53), the area of CC in the INL (R> -0.62) and the OPL+HFL complex (R> -0.55), the density of vessels in the SCP at a distance of up to 2.5° from the fixation point (R>0.51) and in the DCP at a distance of up to 5° from the fixation point (R>0.49). The P1 amplitude correlates with the basal diameter of the hole (R= -0.38), the area of CC in the INL and the OPL+HFL complex (R> -0.33) and vessel density in the SCP (R=0.37) at a distance of up to 2.5° from the fixation point, as well as vessel density in the DCP at a distance of up to 5° from the fixation point (R=0.47). Vessel density in the DCP is significantly lower in the presence of CC in the retina (p<0.001). In FTMH, there is a relationship between bioelectrical activity and LS, and structural disorders, capillary perfusion in different layers of the retina. A multimodal topographically oriented approach allows studying the relationship between structural and functional parameters in individual points of the retina and can be used in monitoring of FTMH after surgical treatment.

CENTRAL BOUQUET HEMORRHAGE: Clinical and Multimodal Imaging Features.

To describe the clinical characteristics, multimodal imaging features, and anatomic basis of a distinctive pattern of deep retinal hemorrhages located in the central fovea, a presentation referred to as "central bouquet hemorrhage." Retrospective, observational, multicenter case series of eyes with central bouquet hemorrhage. Multimodal imaging features were reviewed and analyzed. Ten eyes from 10 patients (4 women and 6 men), with a mean age of 55.6 ± 21.7 years (range 25-84 years) were included. Underlying etiologies were neovascular age-related macular degeneration (40%), lacquer cracks in pathological myopia (30%), macular telangiectasia Type 2 (10%), proliferative diabetic retinopathy (10%), and ocular trauma associated with angioid streaks (10%). On ophthalmoscopy, all eyes with central bouquet hemorrhage displayed a deep retinal hemorrhage with round margins in the central fovea and associated with petaloid hemorrhages radiating in the surrounding Henle fiber layer. Cross-sectional optical coherence tomography showed a well-delineated round hyperreflective lesion involving the central foveal Henle fiber layer/outer nuclear layer in all cases. Accompanying hyperreflective hemorrhages tracking along the obliquely oriented Henle fiber layer were present in all eyes. Resolution occurred in all patients, either spontaneously (30%) or after treatment with intravitreal anti-vascular endothelial growth factor injections (70%), and was associated with partial visual acuity improvement (from 20/113 to 20/36). "Central bouquet hemorrhage" is a novel descriptive term describing a characteristic round pattern of intraretinal blood in the fovea associated with Henle fiber layer hemorrhage and encountered in a spectrum of macular disease.

Angular Sign of Henle Fiber Layer Hyperreflectivity in Purtscher and Purtscher like Retinopathy.

Angular Sign of Henle Fiber Layer Hyperreflectivity (ASHH) is a marker of Henle Fibre layer ischemia. Our aim is to describe ASHH as a novel OCT sign in Purtscher and Purtscher like retinopathy. Here we present 3 Cases, one classical Purtscher Retinopathy and 2 Purtscher like Retinopathy who had ASHH on SD OCT imaging. Modalities like Colour fundus photography, cross-sectional OCT, OCT angiography (OCTA) and fluorescein angiography were used. Presence ASHH in Purtscher Retinopathy and Purtscher like retinopathy points towards a deep capillary plexus insult and has prognostic implications.

Pathophysiology of Secondary Macular Hole in Rhegmatogenous Retinal Detachment.

To describe the pathophysiology of secondary macular hole (MH) in rhegmatogenous retinal detachment (RRD). A retrospective cohort of 360 consecutive primary fovea-off RRDs presenting to St. Michael's Hospital, Toronto, from January 2012 to September 2022 were included. Preoperative OCT was assessed for bacillary layer detachment (BALAD) abnormalities. Histological sections of normal eyes were assessed to inform OCT interpretations. Primary outcome measure was the progression of BALAD to full-thickness MH (FTMH). Of the 360 patients, 22.5% (n = 81) had BALAD abnormalities at presentation. Eight percent (29/360) had associated MH, of which 79.3% (23/29) were a BALAD-lamellar hole and 20.7% (6/29) were FTMH. After reattachment, 62% of MHs persisted (18/29), of which 83% (15/18) had BALAD-lamellar holes that subsequently progressed to FTMH in a mean of 8.1 ± 3.2 days. BALAD-lamellar holes had significantly worse postoperative visual acuity (P < 0.001) when compared with other BALAD abnormalities (58/81) or with the rest of the cohort (279/360). OCT spectrum from BALAD to FTMH includes (1) cleavage planes extending from Henle fiber layer into the BALAD; (2) central outer nuclear layer thinning; (3) Müller cell cone loss with tissue remnants at the foveal walls; (4) retinal tissue operculum close to BALAD-MH; and (5) progressive thinning or degradation of the posterior band of BALAD-lamellar hole leading to FTMH. Histological specimens identified foveal regions of low mechanical stability. BALAD plays a crucial role in the pathophysiology of MH in RRDs, which forms owing to sequential changes in four critical areas: RPE-photoreceptor interface, myoid zone, Henle fiber layer, and Müller cell cone with surrounding tissue. Timely management of fovea-off RRD with BALAD may be prudent to avoid the progression to BALAD-lamellar hole, subsequent FTMH, and worse functional outcomes.