Pilote Mongo C# :désérialiser BsonValue

Voici comment procéder :

using MongoDB.Bson.Serialization;

MongoServer srv = MongoServer.Create(myConnStr);
BsonDocument doc = srv["db"]["products"].FindOneById(ObjectId.Parse("abcdef01234"));
BsonValue dimVal = doc["Dimensions"];
List<Dimension> d = BsonSerializer.Deserialize<List<Dimension>>(dimVal.ToJson());