Ophthalmology over the decades: A catalyst of innovation in the 1970s

As part of Ophthalmology Times’ 50th anniversary, this timeline highlights key technological advances in ophthalmology, beginning with breakthroughs in the 1970s that paved the way for decades of innovation and have enhanced the diagnosis and treatment of various eye conditions up to the present day.

Refinements in cataract surgery took center stage, marked by major improvements in phacoemulsification techniques, advancements in A-scan ultrasound technology for precise ocular measurements, and the introduction of more sophisticated IOLs. These innovations significantly transformed ophthalmology by enhancing surgical precision and delivering better visual outcomes for patients undergoing cataract surgery.

Extracapsular cataract extraction

During this decade, extracapsular cataract extraction (ECCE) became the preferred method over intracapsular cataract extraction (ICCE) due to the severe blinding complications linked to ICCE. With conventional ECCE, the entire lens nucleus was removed through a 10-mm incision.¹

Phacoemulsification, first developed by Charles Kelman, MD, in the late 1960s, revolutionized cataract surgery by reducing the incision size to approximately 3 to 4 mm. In addition, an ultrasound-driven needle was used to emulsify and aspirate the cataractous lens.²

As with the introduction of many innovative procedures, phacoemulsification was initially met with resistance but is now considered the safest and the preferred method of cataract surgery in the developed world.³ Its smaller incision results in a more stable anterior chamber throughout the surgery, shorter recovery times, and less surgically induced astigmatism.¹

IOLs make an impact

The development of IOLs marked a pivotal shift in ophthalmology, moving beyond simply removing cataracts to more precisely restoring vision.¹ Although Harold Ridley, MD, introduced IOLs in 1949, their implantation became a more accepted and refined treatment for aphakia during the 1970s. The earliest lenses were made from polymethylmethacrylate, but by the 1970s, materials evolved from hydrogels—used to create the first foldable lenses in the 1950s—to acrylic, resulting in improved optical quality and better visual outcomes.⁴

The first foldable silicone IOL was implanted in human eyes in 1978 by Chinese eye surgeon Kai-yi Zhou. These IOLs were rapidly adopted by the ophthalmic community and went on to dominate the market throughout the 1980s. Foldable silicone IOLs further reduced the incision size and improved patient comfort and recovery times.^4,5

Early refractive designs of multifocal IOLs were introduced in the 1970s, enabling correction of both distance and near vision within a single lens. This innovation further enhanced visual outcomes for patients. Early designs, such as the 2-zone refractive multifocal IOL, allowed for improved refractive results after surgery, according to the National Institutes of Health.¹

Ophthalmic viscosurgical devices

Ophthalmic viscosurgical devices (OVDs), introduced in 1972, are gel-like substances that significantly enhanced the safety and efficiency of cataract surgery. They maintain space within the eye, protect internal structures, and enable smoother surgical maneuvers. Additionally, OVDs prevent the globe from deflating and safeguard delicate eye tissues without disrupting the surgical process, further improving outcomes.⁶

A-scan ultrasound

A-scan ultrasound technology enabled more accurate measurements of the eye, which in turn allowed for more precise selection of IOL powers, significantly improving visual outcomes after cataract surgery—its most common application. Beyond measuring axial length, this technology also assists in evaluating tumors such as choroidal melanomas, detecting lens dislocation, and identifying retinal detachments. Ultrasonography is particularly valuable when the fundus cannot be visualized through slit lamp or laser interferometry, such as in cases of dense cataracts. Additionally, ocular ultrasonography can facilitate earlier detection of ocular melanoma by characterizing tumor structure and composition based on factors such as height, regularity, reflectivity, and sound attenuation of the echoes.⁷

Argon lasers

In the 1970s, the argon laser transformed ophthalmology by providing a noninvasive treatment option for various eye conditions. One of its primary uses during this time was in managing diabetic retinopathy. The ETDRS trial (NCT00000151) demonstrated the effectiveness of argon laser panretinal photocoagulation in preventing vision loss for patients with proliferative diabetic retinopathy. This laser treatment helped control neovascularization and macular edema linked to the disease.⁸

Beyond diabetic retinopathy, the argon laser was also applied to treat age-related macular degeneration, particularly extrafoveal chorioretinal lesions; glaucoma, by enhancing aqueous humor outflow and lowering IOP; and retinal tears, detachments, and other retinal disorders involving neovascularization and vascular lesions. During this era, argon lasers were used in techniques such as focal and panretinal photocoagulation along with grid photocoagulation to treat macular edema. The introduction of slit lamp–based delivery systems greatly enhanced the precision and control of these treatments.The argon laser’s ability to be strongly absorbed by hemoglobin and melanin made it a valuable tool for targeting blood vessels and other pigmented structures in the eye.^8,9

Glaucoma treatment advances

The 1970s witnessed the advent of the first modern hypotensive eye drops, including timolol—a β-blocker that lowered IOP by reducing fluid production in the eye. This breakthrough paved the way for later advancements in topical glaucoma treatments.¹⁰

Additionally, this decade saw the introduction of ocular drug delivery systems, such as the pilocarpine polymer-membrane unit for treating open-angle glaucoma. These sustained-release systems improved treatment effectiveness and patient adherence by delivering medication more consistently over time.

Other developments during the 1970s include the following:

Pars plana vitrectomy: In 1970, Robert Machemer, MD, performed the first pars plana vitrectomy, which revolutionized the treatment of vitreoretinal diseases by enabling surgeons to access and operate on the retina and vitreous through small incisions.¹¹

Indocyanine green angiography: In 1972, R. W. Flower and Bernard Hochheimer, PhD, developed indocyanine green angiography, a diagnostic technique used to visualize the choroidal circulation and diagnose various retinal disorders.¹²

Adaptive optics systems: Beginning in 1978 at the University of Heidelberg, wavefront measurement and compensation principles were adapted for ophthalmology. Adaptive optics systems were developed to measure and compensate wave aberrations of the human eye with closed-loop control. These systems use wavefront sensors to measure aberrations in the optical system and then deformable mirrors to correct these aberrations in real time, improving image quality for retinal imaging and vision testing. The closed-loop control ensures continuous correction of aberrations as the eye changes.¹³

Finally, in 1979, the American Academy of Ophthalmology and Otolaryngology divided into 2 separate entities: the American Academy of Ophthalmology and the American Academy of Otolaryngology–Head and Neck Surgery. This split reflected the growing specialization and distinct development of these 2 medical fields.¹

References:

1. Davis G. The evolution of cataract surgery. Mo Med. 2016;113(1):58-62.

2. 50 years of phacoemulsification. Ophthalmology Management. November 1, 2017. Accessed August 22, 2025. https://ophthalmologymanagement.com/issues/2017/november/50-years-of-phacoemulsification/

3. Gurnani B, Kaur K. Phacoemulsification. In: StatPearls [Internet]. StatPearls Publishing; updated June 11, 2023. Accessed September 22, 2025. https://www.ncbi.nlm.nih.gov/books/NBK576419/

4. Kretz F, Scholtz S, Auffarth G. A brief history of IOL materials. The Ophthalmologist. May 19, 2014. Accessed August 22, 2025. https://theophthalmologist.com/issues/2014/articles/may/a-brief-history-of-iol-materials

5. Zhou KY. Silicon intraocular lenses in 50 cataract cases. Chin Med J (Engl). 1983;96(3):175-176.

6. Borkenstein AF, Borkenstein EM, Malyugin B. Ophthalmic viscosurgical devices (OVDs) in challenging cases: a review. Ophthalmol Ther. 2021;10(4):831-843. doi:10.1007/s40123-021-00403-9

7. Ringeisen AL, Shlensky D, Murchison A, Justin GA, Hsu J. Ophthalmologic ultrasound. EyeWiki. Updated January 16, 2025. Accessed August 22, 2025. http://eyewiki.org/Ophthalmologic_Ultrasound

8. Photocoagulation treatment of proliferative diabetic retinopathy: the second report of diabetic retinopathy study findings. Ophthalmology. 1978;85(1):82-106. doi:10.1016/s0161-6420(78)35693-1

9. DeBoer CMT, Smith SJ, Blumenkranz MS.Milestones in retina: laser therapy. American Society of Retina Specialists. 2021. Accessed September 22, 2025. https://retinahistory.asrs.org/milestones-developments/laser-therapy

10. Karmel M. Glaucoma drops: Rx for success, or trouble? EyeNet Magazine. March 1, 2009. Accessed September 22, 2025. https://www.aao.org/eyenet/article/glaucoma-drops-rx-success-trouble

11. Omari A, Mahmoud TH. Vitrectomy. In: StatPearls [Internet]. StatPearls Publishing; Updated July 25, 2023. Accessed September 22, 2025. https://www.ncbi.nlm.nih.gov/books/NBK551668/

12. Fernández M, Gil M, Gonzalez F, Gómez-UllaF. Diagnostic usefulness of indocyanine green angiography (ICGA) in age-related macular degeneration (AMD). AMD Book. July 2017. Accessed August 22, 2025. https://amdbook.org/content/diagnostic-usefulness-indocyanine-green-angiography-icga-age-related-macular-degeneration-am

13. Jayabalan GS, Bille JF. Chapter 16: the development of adaptive optics and its application in ophthalmology. In: Bille JF, ed. High Resolution Imaging in Microscopy and Ophthalmology. Springer; 2019.

14. Truhlsen SM. Whatever happened to the EENT specialists? Surv Ophthalmol. 2013;58(1):92-94. doi:10.1016/j.survophthal.2012.04.001