G.R. No. 84846 - Aguja vs. Government Service Insurance System

Jesus D. Aguja was employed as a janitor in the Office of the Municipal Treasurer in Libmanan, Camarines Sur.
In April 1979, while cleaning the office’s toilet, a bottle of muriatic acid suddenly fell to the floor.
The acid splashed, causing significant injury:

The petitioner’s right eye was struck, leading to a gradual loss of vision that eventually resulted in complete blindness.
The petitioner’s left eye was affected by the accident, developing a pterygium on the nasal side, which disturbed his vision (documented as having a vision of 20/40).

Based on the accident, Aguja initially filed for compensation benefits under PD 626, as amended.
He was first granted temporary total disability benefits from September 5 to 29, 1979.
This was followed by an award of permanent partial disability benefits for a period of twenty-five (25) months.

After receiving the initial awards, the petitioner sought additional benefits on the ground of permanent total disability.
His claim was based on the worsening condition of his left eye, which, though not completely blind, was gradually deteriorating due to the pterygium and other complications.
The Government Service Insurance System (GSIS) denied the claim, stating that:

The petitioner had already received the maximum awardable benefits.
The condition of the left eye (alleged to have relatively normal vision) did not meet the criteria for permanent total disability.

The petitioner elevated his case to the Employees Compensation Commission (ECC), which later affirmed the GSIS decision on November 10, 1988.
The petitioner was notified of the ECC decision on January 8, 1989.
Unaware of the denial and seeking further relief, he petitioned the Court for additional benefits.
The Court initially dismissed the petition as premature in its February 10, 1988 resolution but simultaneously directed the ECC to expedite its handling of the claim.

The petitioner moved for reconsideration by attaching the ECC decision.
In a June 15, 1988 resolution, the Court revived the case and allowed for further submissions.
On September 15, 1990, the Court ordered the petitioner to secure satisfactory medical proof regarding the condition of his left eye.
A later resolution (dated November 26, 1990) directed the Public Attorney’s Office (PAO) to assist the petitioner in obtaining the required medical certificate.
The medical certificate revealed:

These findings confirmed that the left eye was gradually losing vision and that the injury could be traced directly to the acid accident in 1979.

The injury’s proximate cause was the accidental fall of the bottle, establishing a clear work-related causal link.
The secondary condition (pterygium and associated ocular injuries) on the left eye was seen as a natural consequence or aggravation of the original injury sustained while on duty.
Retrospectively, the deterioration of the left eye, though gradual and occurring after the initial period, was directly connected to the work incident.

Whether the petitioner, Jesus D. Aguja, is entitled to additional compensation benefits by converting his permanent partial disability award to one of permanent total disability.

Does the gradual deterioration of the petitioner’s left eye warrant qualification for permanent total disability benefits under PD 626, as amended?
Is the medical evidence provided, which indicates worsening conditions (such as pterygium and immature cataract), sufficient to establish the work-related aggravation that qualifies him for a higher grade of disability benefits?