What is a Cataract: Causes, Symptoms, Treatment Options, and Solutions with Advanced Care in Japan
- sakai208
- Nov 10
- 5 min read
Updated: Nov 21
I. Introduction: What is a Cataract? The Clouding of the Natural Lens
The term "what is a cataract" refers to the clouding of the eye’s natural lens. As the world’s leading cause of blindness, understanding its nature and treatment is crucial. Modern surgery is safe and effective, and seeking treatment in Japan offers access to world-class surgical precision and the broadest selection of advanced Intraocular Lens (IOL) technology, optimizing vision for the patient's entire life.
II. Fundamental Understanding & Symptoms
A cataract is the progressive opacification of the lens protein (what causes cataracts), often starting as a subtle change in middle age.
1. Symptoms:
Cataracts typically develop slowly and painlessly. The most common symptoms include:
Clouded or Blurry Vision: Often described as looking through a frosty window.
Glare and Light Sensitivity (Haloes): Increased difficulty seeing in bright sunlight or seeing rings (halos) around lights at night.
Poor Night Vision: Driving becomes increasingly difficult due to reduced contrast and heightened glare from headlights.
Fading or Yellowing of Colors: Colors may appear less vibrant or have a brownish/yellowish tint.
Frequent Changes in Prescription: A temporary period of "second sight" where near vision improves due to the cataract's swelling, followed by a rapid progression of nearsightedness.
2. Types and Classification:
Cataracts are classified to determine surgical complexity and impact on vision:
Anatomical Types: Nuclear (center, causes hardening and yellowing), Cortical (periphery, causes glare/halos), and Posterior Subcapsular (PSC) (rear surface, severe reading difficulty).
Etiological Types: Age-Related (most common), Traumatic, Secondary (due to diabetes, steroids), and Congenital.
Professional Grading (grades of cataracts): Specialists use systems like LOCS III or the Emily-Little Classification to assess lens hardness and density, which is critical for planning the safe surgical removal of the lens.
III. Progression of the Disease: The stages of cataract
Cataracts progress through defined stages, guiding the specialist on the optimal time for surgical intervention.
Early Stage: Small areas of opacity develop, often near the periphery. Vision is typically unaffected, or the patient notices only mild glare.
Immature Stage: The opacity spreads, involving the center of the lens. Visual acuity begins to noticeably decline, impacting daily activities like driving or reading.
Mature Stage: The entire lens is densely cloudy, often appearing white or yellow to the observer. Vision is severely limited to light perception.
Timing for Intervention: In Japan, the decision for surgery is rarely based solely on the physical stage of the cataract; it is based on the impact on the patient's quality of life (QOL). If the cataract interferes with work, driving, hobbies, or independence, the specialist will recommend surgery, even if the cataract is not yet "mature." This approach prioritizes the patient's functional vision over a rigid progression timeline.
IV. Treatment Options
While eye drops may be prescribed in the very early stages to potentially slow progression, surgical extraction of the cataract is the only definitive cure for a cataract.
The primary techniques are:
Phacoemulsification (Modern Standard): Uses a tiny incision (<3mm) and ultrasound energy to break up and suction out the lens. This is the global gold standard for most cases.
Extracapsular Cataract Extraction (ECCE): A larger incision manual method, now reserved for extremely hard (mature) cataracts.
FLACS (Femtosecond Laser-Assisted Cataract Surgery): The most advanced technique, using a laser to automate critical steps (incision, lens fragmentation), significantly reducing the need for ultrasonic energy and increasing IOL placement precision.
2. The IOL Revolution (The Japanese Advantage)
After the cloudy lens is removed, it is replaced with a clear, artificial Intraocular Lens (IOL). This is where modern cataract surgery becomes refractive surgery. Japanese clinics offer an advanced array of IOL options:
Monofocal Lenses: The standard, providing clear vision at a single distance (usually far), requiring glasses for near tasks.
Multifocal/Trifocal Lenses: These revolutionary lenses correct vision at multiple distances (near, intermediate, and far), often allowing for complete independence from glasses.
Extended Depth of Focus (EDOF) Lenses: Offer a continuous range of high-quality vision, particularly effective for minimizing night-time side effects like glare.
Light Adjustable Lens (LAL): The Light Adjustable Lens allows the surgeon to non-invasively fine-tune the prescription after the surgery is complete, eliminating refractive surprise.
Japanese specialists are highly experienced in IOL selection, utilizing precise pre-operative biometry and diagnostic imaging to match the perfect advanced lens to the patient's anatomy and lifestyle.
V. Specialized Challenge: Post-Refractive Eyes
Cataract surgery after LASIK or other laser eye surgery is highly complex because the laser permanently changes the corneal shape, making IOL power calculation extremely difficult (high risk of refractive surprise).
Mitigation: Japanese specialists mitigate this risk by using advanced formulas (e.g., Barrett True-K) and specific diagnostic equipment. For highest predictability, they often recommend LAL or Monofocal IOLs.
VI. Risks and Adverse Effects
While surgery is extremely safe, understanding potential drawbacks is part of the informed consent process.
Infection (Endophthalmitis): Extremely rare, but serious. Prevented by Japan’s strict sterile protocols and prophylactic antibiotics.
Posterior Capsular Rupture (P.C.R.): Tearing of the lens capsule during removal, managed by specialized techniques.
Long-Term Risk (PCO): Posterior Capsule Opacification ("secondary cataract") is common but easily treated with an outpatient YAG laser capsulotomy.
These are common and affect QOV, even in a successful surgery:
Dysphotopsia: Visual disturbances (halos, glare, light streaks, or shadows) resulting from the IOL optics, most often with multifocal lenses.
Dry Eye Syndrome: Temporary dryness due to nerve disruption.
Structural Side Effects: Temporary ptosis (drooping eyelid).
VII. Recovery and Specialized Post-Op Care
Safe and rapid healing depends heavily on post-operative adherence.
Vision improvement is rapid (often driving quality by Day 1). Full stabilization takes 1–3 months.
2. Restrictions
Patients must strictly adhere to rules to protect the IOL and incision:
Avoid Eye Rubbing: Critical for preventing flap or IOL displacement.
Water Contamination: No swimming, hot tubs, or dirty water exposure for at least one month.
Heavy Lifting/Bending: Restricted initially to prevent temporary IOP spikes.
VIII.Cost and Comprehensive Care in Japan
The cost of cataract surgery in Japan reflects the quality of the technology and expertise provided.
1. Cost Factors
The total surgical cost depends heavily on the lens selected and the surgical technique:
Lens Choice: Standard Monofocal IOLs are the base price. Advanced Multifocal/Trifocal/EDOF lenses significantly increase the cost due to the technology and the increased complexity of the planning required.
Technology: The use of a Femtosecond Laser to assist in creating precise incisions and softening the lens before ultrasound removal (Femto-Cataract Surgery) adds cost but enhances safety and precision.
2. Value of Japanese Care
For international patients paying out-of-pocket, the investment covers:
The Broadest IOL Selection: Access to all FDA/EU approved and cutting-edge Japanese-developed lenses.
Surgical Precision: Execution by surgeons with high volume experience and micro-level precision.
Meticulous Biometry: World-class diagnostic measurements crucial for accurate IOL power calculation, providing the best possible refractive outcome.
3. Estimated Costs Per Eye.
Monofocal Lens: 450,000 JPY to 800,000 JPY
(Approx: ~$2,860 - $5,100 USD / ¥20,500 - ¥36,000 CNY / ₱168,000 - ₱300,000 PHP / ₹239,000 - ₹425,000 INR / Rp47,000,000 - Rp84,000,000 IDR / ฿105,000 - ฿185,000 THB)
Multifocal Lens: 800,000 JPY to 1,200,000 JPY
(Approx: ~$5,100 - $7,600 USD / ¥36,000 - ¥54,500 CNY / ₱300,000 - ₱450,000 PHP / ₹425,000 - ₹640,000 INR / Rp84,000,000 - Rp125,000,000,000 IDR / ฿185,000 - ฿280,000 THB)
Note: The exchange rates above are approximate and subject to daily fluctuations. The final cost will be paid in Japanese Yen.
IX. Conclusion: Achieving Clarity: The Promise of Safe and Precise Japanese Surgery
The question "what is a cataract" should be answered with the assurance that it is a common condition with a highly effective, safe solution. Modern cataract surgery offers not just the removal of cloudiness but a powerful opportunity for refractive correction.
By choosing the advanced medical care in Japan, patients secure the highest standard of safety, gain access to the most sophisticated IOL options for true spectacle independence, and benefit from a thorough post-operative follow-up commitment—ensuring not just vision, but the best quality of life.
This article was reviewed by
Dr. Daiki Sakai, MD