diff --git a/DicomGrepCore/Enums/MatchPatternEnum.cs b/DicomGrepCore/Enums/MatchPatternEnum.cs
index 3ff15f1..8c93908 100644
--- a/DicomGrepCore/Enums/MatchPatternEnum.cs
+++ b/DicomGrepCore/Enums/MatchPatternEnum.cs
@@ -9,6 +9,7 @@ namespace DicomGrepCore.Enums
     public enum MatchPatternEnum
     {
         Normal,
+        Wildcard,
         Regex
     }
 }
diff --git a/DicomGrepCore/Extensions/StringExtensions.cs b/DicomGrepCore/Extensions/StringExtensions.cs
deleted file mode 100644
index 6a90d64..0000000
--- a/DicomGrepCore/Extensions/StringExtensions.cs
+++ /dev/null
@@ -1,15 +0,0 @@
-using System;
-using System.Collections.Generic;
-using System.Text;
-
-namespace DicomGrepCore.Extensions
-{
-    public static class StringExtensions
-    {
-        public static bool CaseInsensitiveContains(this string text, string value,
-                            StringComparison stringComparison = StringComparison.CurrentCultureIgnoreCase)
-        {
-            return text.IndexOf(value, stringComparison) >= 0;
-        }
-    }
-}
diff --git a/DicomGrepCore/Services/SearchService.cs b/DicomGrepCore/Services/SearchService.cs
index 26886d3..b8338e8 100644
--- a/DicomGrepCore/Services/SearchService.cs
+++ b/DicomGrepCore/Services/SearchService.cs
@@ -1,5 +1,4 @@
-using DicomGrepCore.Extensions;
-using DicomGrepCore.Entities;
+using DicomGrepCore.Entities;
 using DicomGrepCore.Services.EventArgs;
 using System;
 using System.Collections.Generic;
@@ -295,52 +294,44 @@ private bool CompareString(string refString, SearchCriteria _criteria, bool isDi
                 return false;
             }
 
-            return CompareString(refString, _criteria.SearchText, _criteria.CaseSensitive, _criteria.WholeWord);
+            string testString = _criteria.SearchText;
 
-        }
-
-        private bool CompareString(string refString, string testString, bool caseSensitive, bool wholeWord)
-        {
-            bool result = false;
             switch (criteria.MatchPattern)
             {
                 default:
                 case MatchPatternEnum.Normal:
-                    if (wholeWord)
-                    {
-                        result = refString.Equals(testString, caseSensitive ? StringComparison.InvariantCulture : StringComparison.InvariantCultureIgnoreCase);
-                    }
-                    else
-                    {
-                        result = refString.CaseInsensitiveContains(testString, caseSensitive ? StringComparison.InvariantCulture : StringComparison.InvariantCultureIgnoreCase);
-                    }
+                    testString = Regex.Escape(testString);
+                    break;
+                case MatchPatternEnum.Wildcard:
+                    testString = Regex.Escape(testString);
+                    testString = testString.Replace(@"\*", ".*").Replace(@"\?", ".{1}");
                     break;
                 case MatchPatternEnum.Regex:
-                    RegexOptions options = RegexOptions.Compiled;
-                    if (!caseSensitive)
-                    {
-                        options |= RegexOptions.IgnoreCase;
-                    }
+                    break;
+            }
 
-                    if (wholeWord)
-                    {
-                        // regex match start
-                        if (!testString.StartsWith('^'))
-                        {
-                            testString = "^" + testString;
-                        }
+            RegexOptions options = RegexOptions.Compiled | RegexOptions.Singleline;
+            if (!_criteria.CaseSensitive)
+            {
+                options |= RegexOptions.IgnoreCase;
+            }
 
-                        // regex match end
-                        if (!testString.EndsWith('$'))
-                        {
-                            testString += "$";
-                        }
-                    }
+            if (_criteria.WholeWord)
+            {
+                // regex match start
+                if (!testString.StartsWith('^'))
+                {
+                    testString = "^" + testString;
+                }
 
-                    result = Regex.IsMatch(refString, testString, options);
-                    break;
+                // regex match end
+                if (!testString.EndsWith('$'))
+                {
+                    testString += "$";
+                }
             }
-            return result;
+
+            return Regex.IsMatch(refString, testString, options);
         }
 
     }