It looks like the knife went by the lateral side of the nose and got stuck somewhere in the maxillary region. A person with such a head injury may be evaluated using X-ray, CT scan, or MRI (MRI can only be used when the penetrating object would not be magnetic, because MRI uses magnetism and could move the object, causing further injury). If someone has been stabbed, call 911 immediately. Lay the stabbed person down and check their pulse and breathing. If the stabbing object is still embedded, do not remove it!