Imaging in pulmonary gangrene shows multiple small cavities joining together to form a large cavity. Mycobacterial
Mycobacteria that can cause cavitations include Mycobacterium tuberculosis and nontuberculous mycobacteria, most commonly Mycobacterium avium complex. Primary tuberculosis is caused by the initial infection with Mycobacterium tuberculosis and rarely results in the formation of lung cavities. 90% of people with primary tuberculosis are able to contain the infection and enter a latent phase. Reactivation tuberculosis, which is caused by the reactivation of latent tuberculosis, results in lung cavities visible on X-ray 30 to 50% of the time. There are frequently multiple cavities, and they most commonly occur in the apical and posterior segments of the upper lobes or the superior segment of the lower lobes. Cavitary tuberculosis is associated with worse outcomes, a higher rate of treatment failure, more frequent relapse after treatment, and a higher risk of transmitting the disease to others. Even after successful treatment with anti-tuberculosis drugs, 20-50% of patients with cavitary tuberculosis have persistent cavities, which results in decreased lung function and increased risk of opportunistic infections by Aspergillus fumigatus and other fungal pathogens.Nontuberculous mycobacteria (NTM) are all mycobacterial species other than Mycobacteria tuberculosis (which causes tuberculosis) and Mycobacterium leprae (which causes leprosy). NTM are found everywhere in the environment but are most commonly found in soil and water. Lung disease is caused by inhaling or ingesting nontuberculous mycobacteria. Unlike tuberculosis, NTM infection is not transmitted from person to person.
This can occur more frequently when a person has CVI. Hence, a person with CVI can look at an optical illusion or abstract picture and perceive something that is significantly different from what a person without CVI will perceive.The presence of CVI does not necessarily mean that the persons brain is damaged in any other way, but it can often be accompanied by other neurological problems, the most common being epilepsy. Diagnosis
Diagnosing CVI is difficult. A diagnosis is usually made when visual performance is poor but it is not possible to explain this from an eye examination. Before CVI was widely known among professionals, some would conclude that the patient was faking their problems or had for some reason engaged in self-deception. However, there are now testing techniques that do not depend on the patients words and actions, such as fMRI scanning, or the use of electrodes to detect responses to stimuli in both the retina and the brain. These can be used to verify that the problem is indeed due to a malfunction of the visual cortex and/or the posterior visual pathway. See also
Cortical blindness

References
Further reading
Tallent, Aubri & Tallent, Andrei (2012). Little Bear Sees: How Children with Cortical Visual Impairment Can Learn to See. Little Bear Sees Publishing, of Wyatt-MacKenzie. p. 156. ISBN 978-1936214822. OCLC 1936214822. Roman-Lantzy, Christine (2019). Cortical Visual Impairment: Advanced Principles. New York: AFB Press. ISBN 978-1616480073. OCLC 1055566701. Roman-Lantzy, Christine (2017). Cortical Visual Impairment: An Approach to Assessment and Intervention 2nd Ed. New York: AFB Press. ISBN 978-0891286882.