B-Scan procedure basics in ophthalmology.pptx

B-Scan procedure basics in ophthalmology

1. B-SCAN Moderator : Dr Gladys R Rodrigues Presenter : Dr Sriraj Alapati

2. INTRODUCTION Brightness scan Complements clinical examination but doesn’t replace it. High frequency : good RESOLUTION : UBM (20-50 MHz) Low frequency : good TISSUE PENETRATION : B Scan ( 8- 10 MHz ) Acoustic Impedance – reflectivity (returning echoes) Gain (40-100 Db) – amplitude of echoes Direct globe / via lid / immersion

3. INDICATIONS A. OPAQUE OCULAR MEDIA Anterior segment : Corneal opacification Hyphemia / Hypopyon Miosis Dense Cataract Pupillary or retrolental membrane Posterior segment : (Point like in B Scan) Vitreous hemorrhage Asteroid hyalosis Vitreous inflammation (endophthalmitis)

4. B. CLEAR OCULAR MEDIA Membrane like in B Scan : PVD, Choroidal detachment, RD, Retinoschisis, PED, ROP, Vitreous cyst, PHPV. Infections / Inflammations: VKH, SO, posterior scleritis, endophthalmitis, neurocysticercosis. Trauma : IOFB , IOL / nucleus subluxation / drop, globe / choroidal rupture, retrobulbar hemorrhage, giant retinal tear. Tumors : RB, cavernous hemangioma, choroidal melanoma, choroidal osteoma. Disc abnormalities : Disc oedema, drusen, coloboma. Orbit : thyroid, CCF. Post surgical : air / gas, silicone oil

5. PROBE ORIENTATION Centre of cornea Perpendicular to cornea Position & relation of lesion to lens & ONH Axial Longitudinal Transverse Perpendicular to limbus AP extent of lesion Parallel to limbus Lateral extent of lesion 4 transverse scans: 94%

6. Upper part of screen corresponds to portion of globe where probe marker is directed.

7. DESCRIPTION OF A LESION 1. Topographic : size, shape, borders, location (clock, disc) 2. Quantitative : A. STRUCTURE Regular homogenous – choroidal melanoma Regular heterogenous – choroidal hemangioma Irregular – RB, mets 3. Kinetic : after movements / mobility (move with eye) Present – PVD Absent – old RD/CD B. REFLECTIVITY (A Scan) High – asteroid, RD, CD Medium – old VH Low – vit cells

8. POINT LIKE IN B SCAN VITREOUS CELLS Point like on high gain settings +/- membranes Endophthalmitis / uveitis Low reflectivity After movements present

9. VITREOUS HAEMORRHAGE Fresh – Fine granular/ pin point echoes with high gain settings PVD / FVP / RD Medium reflectivity After movements present Old – Blood clots and membranes (dot like echoes organize) of varying reflectivity. After movements absent PVD FVP

10. ASTEROID HYALOSIS Calcium salts in vitreous cavity Point like larger, more echogenic than RBCs. Echolucent gap between vitreous and posterior globe wall. High reflectivity After movements present

11. Point like Vitreous cells Vitreous hemorrhage Asteroid hyalosis Topographic Point like with high gain Endophthalmitis / uveitis Point like with high gain PVD / FVP – PDR / RD Point like larger, more echogenic than RBCs. Echolucent gap Reflectivity Low Medium (fresh) low (old) High After movement Present Present (fresh) / absent (old) Present

12. MEMBRANE LIKE IN B SCAN PVD Separation between posterior vitreous cortex & NSR Myopes, old age Smooth, thin, mobile membrane, open funnel +/- disc insertion, inserts at ORA / CB Variable amplitude Low reflectivity After movements present Vitreous attached to retina : vitreous base is strongest ( ora serrata ), optic disc margin, macula, main retinal vessels,  lattice degeneration .

13. RETINAL DETACHEMENT Bright, continuous Smooth or folded Open or closed funnel Disc and ORA insertion Steeply rising peak 80-100% reflectivity After movements present in fresh (acute) and absent in old RD. Rhegmatogenous Tractional Exudative Combined

14. Long standing RD with intra retinal cyst , fixed retinal folds, thin retina. Total RD : triangular / funnel (open/closed) shape with insertion at optic disc and ORA serrata.

15. RD RHEGMATOGENOUS TRACTIONAL EXUDATIVE Topographic Funnel / double membrane Folds +, retinal break+ Attached to disc Concave, tent like traction +/- FVP / VH (PDR) Convex , bullous Shifting fluid Scleral thickening Mass lesions, Sys causes Reflectivity High High High After movement Present (fresh) / absent (old) Absent Absent

16. CHOROIDAL DETACHEMENT Smooth, dome shaped Multiconvex / multilobed Immobile Kissing choroids No disc insertion Inserts at ORA / CB Don’t extend to posterior pole (vortex veins) Steeply rising double peak (retina, choroid) 90-100% reflectivity After movements absent Hypotony : GDD Sulfonamides Expulsive choroidal Hg #PCA: Uncontrolled HTN Sudden decompression of high pre op IOP 2. HEMORRHAGIC SEROUS

17. Membrane Like PVD RD CD Shape Concave Double membrane / concave / convex Multi convex (dome) Location Variable Variable Periphery (vortex veins) ONH Attachments Variable Yes No Types - Rhegmatogenous / Tractional / Exudative / Combined Serous / hemorrhagic Cause Myopia / age Break / FVP / Sys cause Hypotony / expulsive choroidal hg Other findings Prominently seen inferiorly Folds / FVP / shifting fluid Kissing choroids Reflectivity (A scan) 40-90% 80-100% 90-100% Spike Single Single Double (retina, choroid) Mobility Marked Moderate Absent Aftermovement + + (fresh Rheg ) / - -

18. Dense anterior membrane with narrow closed funnel RD Elevated smooth thin dome shaped membrane, often bilateral RETINOSCHISIS ROP

19. VITREOUS CYST Dome shaped serous lesion PED PHPV Tent like retinal dragging Fluid filled structure with reflective walls

20. INFECTIONS / INFLAMMATIONS CYSTICERCOSIS Pork tape worm S/R cyst with RD (reverse diamond ring sign) High reflectivity spikes SCOLEX

21. ENDOPHTHALMITIS Cobweb appearance (highly reflective membranes) SYMPATHETIC OPHTHALMOPLEGIA 2 weeks After penetrating trauma Choroidal thickening with exudative RD

22. B/L disc oedema Choroidal thickening & areas of bullous retinal elevation at posterior pole VKH T sign (tenons fluid + optic nerve hypo intensity) Choroidal thickening Scleral thickening ERD POSTERIOR SCLERITIS

23. SUBLUXATED LENS PCR IOL DROP (Multiple high reflectivity echoes) TRAUMA NUCLEAS DROP (Biconvex with shadow)

24. GLOBE RUPTURE Hemorrhagic vitreous track CHOROIDAL RUPTURE Focal area of fundus thickening

25. RETROBULBAR HEMORRHAGE GIANT RETINAL TEAR

26. Posterior shadowing Persistence at lower gain High reflectivity spikes >100% Overestimation of size Vitreous / retinal / subretinal / orbital Metal & stone : higher reflective echoes Wood & vegetable matter : intermediate echoes Glass is picked only when sound beam strikes perpendicular along smooth surface of glass. Spherical IOFBs produce strong reverberations due to regular structure. Air bubble may mimic foreign body IOFB

27. TUMORS Calcification produce high reflectivity and shadowing Endophytic – vitreous echoes Exophytic – ERD with subretinal echoes RETINOBLASTOMA

28. Choroidal melanoma Collar-button / mushroom / dome shape : Knapp roone tumor break in bruchs membrabe Exudative RD Choroidal excavation Steep angle kappa Acoustic hollowing Vascularity on color doppler

29. Cavernous Hemangioma High reflectivity with shadowing at posterior pole, double optic nerve Choroidal osteoma Intraconal Heterogenous structure Varying reflectivity No color flow on doppler

30. DISC ABNORMALITIES Patient to fixate in primary gaze. Probe placed longitudinal, temporally with medium gain setting . Normal ONH seen as round echo lucent lesion adjacent to globe with shadowing. Disc oedema : crescent or doughnut sign

31. DISC ELEVATION DRUSEN Enlarged optic nerve With low gain settings

32. GLAUCOMATOUS OPTIC CUPPING OPTIC DISC COLOBOMA Bean pot configuration

33. ORBIT Enlargement muscle belly sparing tendinous insertion TED Dilated SOV CCF

34. High reflective curvilinear echo with comet tail shadowing . Echo seen in non dependent location as air bubble floats. High reflective echoes. Single large air bubble causing strong reverberations. Apparent lengthening of eye waves pass slow. AIR / GAS SILICON OIL POST SURGICAL

35. THANK YOU

36. Q1. Patient c/o pain with blurring of vision. Fundus examination shows choroidal folds with localized elevation of the retina Findings on B scan and diagnosis? T sign Scleral & choroidal thickening RD POSTERIOR SCLERITIS

37. Q2. Patient with sudden blurring of vision. There is no view of the fundus. Findings on B scan? VH PVD RD

38. Q3. Patient diagnosed to have bilateral disc elevation on routine examination. V/A and colour vision is normal. Diagnosis? DISC DRUSEN

39. Q4. Patient presents with blurring of vision. Examination shows low IOP & mature cataract with no view of fundus. Findings on B scan? RETINAL DETACHEMENT Low IOP? Fresh : RPE actively pumps fluid Old : CB shutdown

40. Q5. Patient with h/o injury at workplace with blurring of vision , S/P cataract surgery 2years ago. Findings on B Scan & Diagnosis? Multiple high reflectivity echoes / reverberations. IOL DROP / Spherical IOFB / Air