'practically unchanged' is correct and usable in written English.
It means that something is almost completely the same as it was before. For example, "After 100 years, the house was practically unchanged."
Of Germanic Swiss origin, the shooting called Schuetzen was practiced for centuries practically unchanged throughout much of central Europe, and by the 1880s it had become predominantly popular.
The legislation is going through practically unchanged.
Surprisingly, the cafe where she brushes off her schoolboy would-be suitor is practically unchanged.
The NSX was left practically unchanged for 16 years before Honda ended production in 2005.
The western coastline of the delta, however, has remained practically unchanged since the 18th century.
It is impossible for melanoma to stay practically unchanged for three and a half years without metastatic consequences.
During this period Man came under a Scandinavian system of government that has remained practically unchanged ever since.
The proportion of Chinese cities with fairly good air quality was practically unchanged last year, while the number of extremely polluted cities declined.
The boy threw it all up in an hour, the steak looking practically unchanged, and became listless and squash-colored for three days.
Viterbo's medieval quarter, enclosed by 11th- to 13th-century walls and towers, remains practically unchanged, with its Romanesque arcades and 13th- and 14th-century houses and palaces.
And here, sitting across the table from me, was the same guy, practically unchanged, with the shaggy bowl cut and the soft voice.
