Penetrating keratoplasty (PKP) is full-thickness corneal transplant surgery. During parts of the operation the eye is “open-sky”—the cornea is removed and the inside of the eye is temporarily open. Positive vitreous pressure (PVP) is when the gel and tissues in the back of the eye (the vitreous cavity, choroid, lens–iris diaphragm) push forward during this open time. The front chamber becomes shallow, the iris wants to slip out, and it can become hard to place or tie sutures safely. Think of the eye as a water balloon: if the front is opened and anything increases pressure behind, the contents bulge forward.
Why this matters: PVP can lead to dangerous events like vitreous/lens prolapse, iris damage, trouble suturing the graft, and in the worst case suprachoroidal hemorrhage (bleeding behind the retina) or even expulsion of intraocular tissues. Reported PVP during PKP is common, with some series describing ~40–50% of cases showing some degree of positive pressure signs when the eye is open. Dove Medical Press
Positive vitreous pressure during PKP is a forward push of the posterior eye tissues (vitreous, lens–iris diaphragm, sometimes choroid) into the open anterior chamber, most often triggered by the sudden drop in intraocular pressure that happens when the cornea is removed. That pressure drop creates a pressure gradient: the back of the eye has higher pressure than the front, so the back pushes forward. External factors (like a tight speculum or squeezing lids), anesthesia factors (like coughing or high ventilator pressures), and eye-specific factors (like shallow anterior chamber or weak zonules) can all add to the push. The result is a shallow or flat anterior chamber, repeated iris prolapse, and a “rock-hard” feeling eye under the surgeon’s finger, right when delicate graft work must be done. In severe cases, the choroid can swell or bleed, which is sight-threatening. Dove Medical PressSpringerLink
Why it happens
Open-sky hypotony: When the cornea is off, the front of the eye loses pressure.
Pressure gradient: The back of the eye (vitreous cavity and choroid) often stays relatively higher pressure.
Forward movement: That difference pushes the lens–iris diaphragm and vitreous forward into the open wound.
Add-on factors: Anything that raises venous pressure in the head/eye (coughing, straining, PEEP on a ventilator, head-down position), or squeezes the globe from outside (tight speculum, heavy drapes), or makes the eye structurally prone (shallow chamber, weak zonules, pediatric eyes), worsens the forward push. Dove Medical PressCybersightPubMed
Types
There isn’t a single universal “official” classification, but in practice surgeons find it helpful to think about PVP in these patterns:
1) By source of the push
Exogenous (outside the eye): Pressure from lids/speculum, drapes pulling on lids, surgeon’s hand pressure on sclera, small or crowded orbit, orbital bleeding after local anesthesia. These make the globe mechanically “squeezed.” CybersightDove Medical Press
Endogenous (inside the eye): The eye itself pushes forward—because of open-sky hypotony, choroidal congestion/effusion, fluid misdirection (“rock-hard eye”) during surgery, or (rare but dangerous) suprachoroidal hemorrhage. SpringerLinkCybersight
2) By timing and behavior
Transient/anticipatable: A mild, brief forward bowing that settles with viscoelastic and gentle steps.
Persistent/problematic: The chamber stays flat, iris keeps prolapsing, suturing is difficult—often needs specific maneuvers (e.g., vitrectomy, special sutures).
Catastrophic: Rapid forward bulge with pain (if under local) and a dark, expanding choroidal shadow—suggesting suprachoroidal hemorrhage. This is an emergency to close the eye and tamponade bleeding. Cybersight
3) By mechanism
Simple gradient PVP from open-sky hypotony alone (most common).
Fluid misdirection / acute intraoperative “rock-hard eye”: Aqueous or irrigation fluid misdirects posteriorly through the zonules, pressurizing the back; the eye becomes very firm and the chamber very shallow despite no obvious external squeeze. Cybersight
Choroidal effusion: Fluid collects in the suprachoroidal space as the eye sits hypotonous; pushes the uveal tissues forward.
Suprachoroidal hemorrhage: Actual bleeding into the suprachoroidal space—sight-threatening and time-critical. SpringerLink
Causes
Open-sky hypotony itself: Removing the cornea drops front-chamber pressure. The back stays higher, so it pushes forward. This is the root driver in most cases. SpringerLink
Tight eyelid speculum or heavy drapes: Mechanical squeeze of the globe from outside makes the eye bulge while the front is open. Cybersight
Lid squeezing or patient straining: Even small attempts to squeeze or cough raise venous pressure and push the lens–iris diaphragm forward. Cybersight
Surgeon or instrument pressure on sclera: A handheld instrument resting on the globe raises pressure and deepens PVP. Dove Medical Press
Retrobulbar/intraorbital hemorrhage after local anesthesia: Extra blood in the orbit compresses the eye from behind. Cybersight
Large volume peribulbar/retrobulbar injection: The injected fluid itself temporarily crowds the orbit and raises pressure. Dove Medical Press
Positive end-expiratory pressure (PEEP) on a ventilator: PEEP increases venous pressure in the head and can create severe PVP during open-sky steps. PubMed
Head-down or poorly elevated head position: Below-heart head position congests the choroid and increases posterior pressure. Dove Medical Press
Obesity / “bull neck” and venous congestion: Neck and chest mechanics can keep venous pressure high in the head, favoring forward push. Dove Medical Press
COPD, chronic cough, or obstructive sleep apnea: Repeated intrathoracic pressure spikes (cough/Valsalva) raise ocular venous pressure. Dove Medical Press
Congestive heart failure or pulmonary edema: Fluid overload and high venous pressure swell the choroid and push forward. Dove Medical Press
Thyroid eye disease or orbital inflammation: The orbit is crowded and stiff; even normal manipulations produce a larger pressure rise. Dove Medical PressCybersight
Orbital tumors or masses: Occupy space and compress the globe from behind. Dove Medical Press
Small orbit or increased orbital fat: Less room in the socket means any swelling or pressure is transmitted to the eye sooner. Dove Medical Press
Shallow anterior chamber / narrow angles: Less front-of-eye space means a small push collapses the chamber quickly. Dove Medical Press
Zonular weakness: A loose lens–iris diaphragm moves forward more easily with pressure surges. Dove Medical Press
Pseudophakia with posterior capsule issues or IOL out of the bag: Lens/IOL can ride forward and worsen PVP; iris or IOL may prolapse. Dove Medical Press
Pediatric/young eyes: Softer, more elastic coats (cornea/sclera) and turgid vitreous let the diaphragm shift forward readily. Dove Medical Press
High myopia or altered scleral rigidity: Changes in scleral/chorioidal behavior can make choroidal congestion or bleeding more likely during hypotony. Dove Medical Press
Anxiety, bucking, or inadequate akinesia/anesthesia: Micro-movements, breath-holding, or straining increase PVP right when the eye is open. Dove Medical Press
Symptoms and Signs
Sudden or persistent shallow/flat anterior chamber even after adding viscoelastic—classic early sign.
Forward shift of the lens–iris diaphragm toward the wound; the pupil looks pushed forward. Dove Medical Press
Recurrent iris prolapse through the trephined wound, especially when instruments are removed.
Hard globe to gentle finger touch (“rock-hard”) during the open-sky step.
Vitreous presenting in the wound or in the anterior chamber.
Lens or IOL moving forward, sometimes threatening to come out if not controlled. SpringerLink
Pupil distortion or sphincter tears from repeated iris prolapse.
Uveal tissue or iris caught in sutures because the chamber cannot be kept deep enough.
Difficulty keeping viscoelastic in the eye—it keeps getting forced out by posterior push.
Choroidal elevation seen on quick indirect ophthalmoscopy (if possible) suggests effusion/hemorrhage. Cybersight
Dark, expanding posterior shadow (sudden) = possible suprachoroidal hemorrhage—emergency. Cybersight
Pain despite local anesthesia (not always present), more concerning for choroidal effusion/hemorrhage. Cybersight
Intraoperative IOP spikes on measurement or by palpation during attempts to suture.
Loss of red reflex clarity while trying to look posteriorly, if bleeding/effusion develops.
Progression from slow firmness to rapid crisis if effusion turns into hemorrhage—warning pattern. Cybersight
Diagnostic Tests
A) Physical examination and chair-side ocular assessment
Slit-lamp estimate of anterior chamber depth (e.g., Van Herick): flags shallow chambers that are more likely to collapse during open-sky steps.
Tonometry (IOP measurement): documents pre-op pressure and helps plan pressure-lowering measures; also used intraoperatively if available. NCBI
Gonioscopy: checks for narrow/closed angles and peripheral anterior synechiae—eyes that decompensate quickly when opened. NCBI
Dilated fundus/indirect ophthalmoscopy (when safe): looks for choroidal elevation or other posterior issues that might worsen with hypotony. Cybersight
External/orbital exam: detects proptosis, tight lids, thyroid signs, or small crowded orbits that can transmit pressure to the globe. Dove Medical Press
B) “Manual” or bedside functional checks (used cautiously, mainly for planning)
Digital ocular tension (light palpation): a quick feel for abnormally firm eyes pre-op when tonometry is unreliable (e.g., scarred cornea). NCBI
Speculum fit check: before trephination, ensure the speculum is not overly tight and drapes aren’t pulling on lids; corrects an avoidable exogenous cause. Cybersight
Response to gentle ocular decompression (Honan balloon/eyelid compression per protocol): sometimes used pre-op to reduce vitreous pressure; the response tells you how easily the eye softens. (This is done by trained staff with strict timing/pressure limits.) NCBI
C) Laboratory / pathological tests (to find systemic contributors)
Complete blood count (CBC) and hematocrit: thick blood (very high hematocrit) or anemia states can change choroidal perfusion and venous pressure behavior.
Coagulation profile (PT/INR, aPTT): bleeding risk if a suprachoroidal hemorrhage occurs; helps plan peri-operative anticoagulants.
Basic metabolic panel & renal function: guides fluid balance; kidney issues can predispose to edema and venous congestion.
Liver function tests: advanced liver disease can alter coagulation and fluid handling, raising PVP risk in open-sky hypotony.
Thyroid function tests (TSH, free T4): helps confirm thyroid eye disease, a cause of orbital congestion.
BNP/NT-proBNP (if indicated): supports heart failure as a contributor to venous congestion and choroidal swelling.
D) Electrodiagnostic / physiologic monitoring (peri-operative)
Electrocardiogram (ECG): baseline cardiac status; heart failure/arrhythmia management reduces venous pressure surges that worsen PVP.
Capnography (end-tidal CO₂) during anesthesia: high CO₂ leads to vasodilation and choroidal congestion; monitoring guides ventilation to avoid PVP surges. (High PEEP has been linked to severe PVP in case reports.) PubMed
E) Imaging (ocular and orbital)
Anterior segment OCT (AS-OCT): measures chamber depth and lens position; helps anticipate a propensity for forward movement during open-sky steps. NCBI
Ultrasound biomicroscopy (UBM): visualizes the ciliary body/angle to detect plateau iris or crowding that can collapse quickly when opened. NCBI
B-scan ocular ultrasound (when corneal opacity blocks the view): can show choroidal effusion or masses and is helpful if PVP or hemorrhage is suspected.
Orbital CT/MRI (select cases): looks for orbital tumors, hematoma, thyroid eye disease—conditions that crowd the orbit and raise posterior pressure. Dove Medical Press
Non-pharmacological treatments (therapies & techniques)
Head-up (reverse Trendelenburg) positioning (≈10–15°) to lower venous pressure and IOP. Purpose: decrease posterior push. Mechanism: reduces episcleral/venous pressure. ScienceDirectPMC
Avoid Trendelenburg and keep surgery time efficient. Mechanism: Trendelenburg raises IOP over time. PMC
Optimize anesthesia depth & paralysis to prevent cough/buck/strain. Mechanism: reduces central venous and IOP surges. Lippincott Journals
Use non-depolarizing neuromuscular blocker (e.g., rocuronium) rather than succinylcholine when feasible in open-eye situations. Mechanism: avoids IOP spikes. PubMed
Minimize PEEP and airway pressures needed for oxygenation. Mechanism: less venous congestion. Lippincott Journals
Gentle draping/speculum—no external pressure. Mechanism: removes extrinsic globe compression. CRSToday
Preplace or quickly place corneal sutures so the eye isn’t open longer than necessary. Mechanism: shortens “open-sky” time (less hypotony).
Use a Flieringa scleral ring when the eye is soft or pediatric to support the globe. Mechanism: distributes forces; prevents scleral collapse/AC loss. Lippincott JournalsNCBI
Anterior chamber maintainer (infusion cannula) to keep the chamber formed. Mechanism: replaces lost fluid and counterbalances posterior push. EyeWiki
High-viscosity viscoelastic (OVD) to tamponade the iris-lens diaphragm and protect endothelium while you work. Mechanism: space maintenance & tissue protection. Lippincott Journals
Check and correct external triggers (tight collar, abdominal drape weight, patient straining). Mechanism: improves venous return. CRSToday
Pause and deepen anesthesia if signs of pressure appear. Mechanism: volatile agents/adequate depth lower IOP and suppress reflexes. Lippincott Journals
Hyperventilate briefly to normocapnia (avoid hypercapnia). Mechanism: high CO₂ raises IOP; normal CO₂ helps. Lippincott Journals
Basket mattress suture (limbus-to-limbus) to “hold back” iris-lens/IOL when pressure persists. Mechanism: temporary mechanical diaphragm. drtanyatrinh.com
Temporary iris hooks or traction sutures to keep the iris flat. Mechanism: prevents it from billowing forward. drtanyatrinh.com
Close and re-form the anterior chamber early if a suprachoroidal issue is suspected; don’t persist with open globe. Mechanism: reduces risk of expulsive hemorrhage. CRSToday
Pars plana vitreous tap/anterior vitrectomy (limited) when needed. Mechanism: removes a small amount of vitreous volume to relieve posterior push. ScienceDirectLippincott Journals
Posterior sclerotomy/choroidal drainage if there’s effusion with anterior shallowing. Mechanism: relieves choroidal pressure—done judiciously. AAO Journal
“Stepwise” preset vitrectomy cannula before opening in very high-risk cases. Mechanism: allows intermittent, controlled decompression. SpringerLink
Team choreography (surgeon–anesthetist communication): “I’m opening” → “airway still, no cough/PEEP”—repeat during critical steps. Mechanism: removes sudden venous surges at key moments.
Drug treatments
Mannitol 20% (IV hyperosmotic) • 1–1.5 g/kg IV over 30–60 min, 30–60 min pre-op or when needed intra-op • Purpose: quickly dehydrate vitreous, lower IOP • Mechanism: raises serum osmolality → fluid leaves vitreous → less posterior push • Side effects: diuresis, electrolyte shifts, dehydration; caution in heart/renal failure. Glaucoma TodayJAMA Network
Acetazolamide (systemic CAI) • 250–500 mg PO/IV pre-op • Purpose: lower IOP and aqueous production; helpful adjunct to mannitol • Mechanism: carbonic anhydrase inhibition → less aqueous production; may affect vitreous fluid flux • Side effects: paresthesia, diuresis, metabolic acidosis; avoid in sulfa allergy. Glaucoma TodayScienceDirect
Glycerol (oral hyperosmotic, 50% solution) • 1.0–1.5 g/kg PO ~30–60 min pre-op • Purpose: alternative to IV agents to lower IOP and deepen AC • Mechanism: raises serum osmolality → vitreous dehydration • Side effects: nausea/vomiting; avoid in diabetes (can worsen hyperglycemia). Glaucoma TodayPubMed
Hypertonic saline 3% (IV) • bolus ~3 mL/kg or per protocol • Purpose: alternative to mannitol when rapid IOP lowering is needed • Mechanism: osmotic dehydration similar to mannitol • Side effects: hypernatremia risk; monitor sodium/osmolality. PubMedWiley Online Library
Dexmedetomidine (IV α2-agonist sedative) • 0.5–1 μg/kg load over 10–15 min, then low infusion as needed • Purpose: smooth sedation, blunts IOP spikes, reduces cough/buck • Mechanism: central sympathetic dampening → lower IOP and hemodynamic stability • Side effects: bradycardia, hypotension. PubMedLippincott Journals
Propofol (IV induction/maintenance) • titrated per anesthesia • Purpose: reduces IOP and suppresses airway reflexes compared with some alternatives • Mechanism: CNS depression and vasodilation lower IOP • Side effects: hypotension, apnea. PMC
Rocuronium (non-depolarizing NMB) • intubating dose per anesthesia • Purpose: secure airway without succinylcholine-related IOP spikes • Mechanism: skeletal muscle relaxation without depolarization • Side effects: rare anaphylaxis; requires ventilatory support. anesthesiaejournal.com
Topical beta-blocker (e.g., timolol 0.5% 1 drop) • pre-op • Purpose: lower aqueous production and IOP • Mechanism: β-blockade at ciliary body • Side effects: bradycardia/bronchospasm in susceptible patients. Glaucoma Today
Topical α2-agonist (e.g., brimonidine 0.2%, apraclonidine 0.5% 1 drop) • pre-op • Purpose: short-term IOP reduction • Mechanism: ↓ aqueous production + ↑ uveoscleral outflow • Side effects: dry mouth, fatigue; caution with clonidine-like effects. Glaucoma Today
Topical carbonic anhydrase inhibitor (e.g., dorzolamide 2% 1 drop) • pre-op • Purpose: adjunct IOP lowering • Mechanism: ↓ aqueous production • Side effects: local stinging, rare sulfa reactions. Glaucoma Today
Drugs to avoid when possible: Succinylcholine (depolarizing NMB) may increase IOP—use only if the airway scenario truly demands it and risks are balanced. PubMed
Dietary & supportive supplements
These do not treat PVP. They support post-operative wound healing and ocular surface recovery. Always clear supplements with the surgeon, especially before surgery.
Vitamin C 500–1000 mg/day — supports collagen and corneal healing; higher tissue levels correlate with better epithelial repair. PMC+1
Vitamin A (retinol/beta-carotene) dietary RDA: 700–900 mcg RAE/day — vital for corneal epithelium/mucin; deficiency causes keratinization/ulceration. Avoid megadoses. PubMed
Omega-3 (EPA+DHA) 1000–2000 mg combined/day after surgeon clears bleeding risk — anti-inflammatory, may help ocular surface comfort. Evidence mixed; benefits likelier at higher EPA doses and longer duration. PMC
Zinc 8–15 mg/day — cofactor in healing; do not exceed 40 mg/day; pair with copper if long-term. PMC
Copper ~0.9–2 mg/day with zinc — supports collagen cross-linking/angiogenesis. PMC
L-Arginine 3–6 g/day — conditionally essential in wound healing (NO pathway, collagen); evidence supportive but not definitive; avoid if you have recurrent ocular herpes. PMC
L-Glutamine 5–15 g/day — immune & gut support; may aid wound recovery. PMC
HMB (β-hydroxy-β-methylbutyrate) 3 g/day — reduces muscle catabolism; sometimes combined with arginine/glutamine in wound care. agingmedhealthc.com
Vitamin D3 1000–2000 IU/day — immunomodulatory, overall healing support.
Vitamin E natural mixed tocopherols ≤200 IU/day — antioxidant (avoid high doses before surgery due to bleeding concerns).
Coenzyme Q10 100–200 mg/day — mitochondrial antioxidant; general recovery support.
Curcumin 500–1000 mg/day with pepper/optimized forms — anti-inflammatory; theoretical bleeding risk—stop pre-op if advised.
Lutein + Zeaxanthin 10 mg + 2 mg/day — retinal antioxidants; general eye nutrition.
Adequate Protein ~1.2–1.5 g/kg/day — substrate for repair (count as nutrition support).
Hydration & electrolytes — maintain perfusion and safe osmolality, especially if hyperosmotics used peri-op.
Regenerative / stem-cell–related” drugs
Topical tacrolimus 0.03–0.1% (with steroids in high-risk grafts) — may reduce rejection rates vs steroids alone in some cohorts; dosing often QID then taper per corneal specialist. Mechanism: calcineurin inhibition (T-cell). Watch: burning, rare pressure rise (usually steroid-related). BioMed CentralPMC
Systemic mycophenolate mofetil (MMF) e.g., 1 g twice daily for limited months in selected high-risk PK — improves rejection-free survival in trials; used under specialist care. Mechanism: inhibits lymphocyte purine synthesis. Watch: cytopenias, infection risk, teratogenicity. NaturePubMed
Topical/implant cyclosporine A (varied strengths/delivery) — evidence mixed for prevention; may help treat rejection episodes; used adjunctively with steroids. Mechanism: calcineurin inhibition. Watch: burning, rare systemic absorption. AAO JournalPubMed
Topical ROCK inhibitors (e.g., ripasudil/netarsudil) after endothelial-sparing procedures (DSO/DWEK) and in research/selected uses — promote endothelial cell migration and wound healing. Watch: conjunctival hyperemia. ScienceDirectPubMed
Cultured corneal endothelial cell therapy + ROCK inhibitor (research/approved in select regions) — cell injection with ROCK inhibitor has shown multiyear safety/efficacy for endothelial failure (not a PVP therapy but relevant to corneal regeneration). New England Journal of MedicineAAO Journal
Systemic corticosteroids (short course in high-risk grafts per specialist) — quell immune activation around surgery; tailored to comorbidities. Watch: glucose, BP, infection risk.
Surgical
Flieringa ring placement — scleral support ring sutured before trephination to prevent globe collapse and AC loss, especially in pediatric/soft eyes. Lippincott JournalsNCBI
Anterior chamber maintainer (balanced salt infusion) — small cannula keeps the chamber formed during the “open-sky” phase, countering posterior push. EyeWiki
Limited pars plana vitreous tap / anterior vitrectomy — removes a small amount of vitreous to reduce posterior pressure so suturing can proceed safely. ScienceDirectLippincott Journals
Posterior sclerotomy/choroidal drainage (when effusion/hemorrhage suspected) — controlled drainage to relieve choroidal expansion; performed carefully with readiness to close. AAO Journal
“Basket” mattress suture across the limbus — temporary suture “fence” that holds iris-lens/IOL back while the graft is secured. drtanyatrinh.com
Practical prevention tips
Treat cough/airway irritation before surgery; antiemetic plan. PMC
Choose non-depolarizing NMB and adequate depth; avoid succinylcholine if possible. PubMed
Keep CO₂ normal, avoid unnecessary PEEP. Lippincott Journals
Head-up tilt, no Trendelenburg. ScienceDirect
Ensure no external pressure from speculum/drapes. CRSToday
Pre-op hyperosmotic/CAI plan for small/shallow eyes (mannitol ± acetazolamide). Glaucoma Today
Consider Flieringa ring and AC maintainer in high-risk eyes. Lippincott JournalsEyeWiki
Preplace sutures / minimize “open-sky” time.
Align team communication (announce critical moments to anesthesia).
Have vitreous tap & sclerotomy tools ready in the room when risk is high. ResearchGate
When to see a doctor urgently
Sudden severe eye pain, headache, or a “rock-hard” eye.
Rapid vision drop, dark curtain or shadow.
Nausea/vomiting with eye pain.
New redness, light sensitivity, or discharge that’s worsening.
Any trauma or pressure to the operated eye.
These can signal pressure problems or bleeding and need immediate care.
What to eat (and avoid) around surgery
Eat more of: lean proteins (eggs, fish, lentils), colorful produce (vitamin A & C sources like carrots, leafy greens, citrus), nuts/seeds (vitamin E), whole grains, and fluids (water/electrolytes). These provide building blocks for healing.
Go easy on: very salty foods (can worsen blood pressure), alcohol (impairs healing), and herbal/supplement “blood thinners” (high-dose fish oil, ginkgo, high-dose vitamin E, curcumin) unless your surgeon okays them. If you’re on anticoagulants, follow your surgeon’s exact plan.
FAQs
Is PVP the same as high IOP?
Not exactly. IOP can be normal yet the back of the eye pushes forward during open-sky. They’re related but not identical.Who’s at highest risk?
Very small/pediatric eyes, shallow chambers, inflamed eyes, and anyone who may cough/strain under anesthesia or be positioned unfavorably. Lippincott JournalsPMCWhy is coughing or straining so bad?
It spikes venous and eye pressure suddenly—exactly when the eye is open. PMCWhy avoid succinylcholine?
It can raise IOP; non-depolarizing agents (like rocuronium) are preferred when feasible. PubMedWhat does mannitol do?
It’s a sugar alcohol that pulls water out of the vitreous, shrinking it for a few hours and easing the posterior push. Glaucoma TodayCan positioning really help?
Yes. A gentle head-up tilt reduces venous/episcleral pressure and IOP. ScienceDirectWhat if pressure still surges?
Surgeons can use an AC maintainer, high-viscosity OVD, basket suture, or a brief vitreous tap to safely continue. EyeWikidrtanyatrinh.comScienceDirectCan PVP cause permanent damage?
It can if it triggers a suprachoroidal hemorrhage, which is why prevention and rapid response matter. surveyophthalmol.comIs PK the only corneal surgery with this risk?
No, but open-sky PK carries more risk than lamellar procedures (DALK, DMEK). PMCDo omega-3s help with this?
They don’t treat acute PVP. They may help ocular surface comfort and healing long-term in some patients. PMCWhat is a Flieringa ring?
A temporary ring sewn to the sclera to keep the globe stable during surgery. Lippincott JournalsWhy is PEEP a problem?
PEEP can raise venous pressure and worsen posterior push in open-eye surgery. Lippincott JournalsCould hypertonic saline replace mannitol?
In some settings, yes—it can lower IOP rapidly too; choice depends on patient factors and institutional protocols. PubMedWhat should patients do pre-op?
Control cough/constipation, avoid heavy meals right before anesthesia, confirm medication/supplement plans, and follow fasting and BP/diabetes instructions.Bottom line for safety?
Plan ahead, keep the airway calm and the head up, avoid external pressure, be ready with infusion/OVD/ring—and have decompression tools on standby. EyeWikiLippincott Journals
Disclaimer: Each person’s journey is unique, treatment plan, life style, food habit, hormonal condition, immune system, chronic disease condition, geological location, weather and previous medical history is also unique. So always seek the best advice from a qualified medical professional or health care provider before trying any treatments to ensure to find out the best plan for you. This guide is for general information and educational purposes only. Regular check-ups and awareness can help to manage and prevent complications associated with these diseases conditions. If you or someone are suffering from this disease condition bookmark this website or share with someone who might find it useful! Boost your knowledge and stay ahead in your health journey. We always try to ensure that the content is regularly updated to reflect the latest medical research and treatment options. Thank you for giving your valuable time to read the article.
The article is written by Team RxHarun and reviewed by the Rx Editorial Board Members
Last Updated: August 12, 2025.
