Another difference that has been cited between organic and psychogenic amnesia is the temporal gradient of retrograde loss of autobiographical memory. The temporal gradient of loss in most cases of organic amnesia is said to be steepest at its most recent premorbid period, whereas for psychogenic amnesia the temporal gradient of retrograde autobiographical memory loss is said to be quite consistently flat. Although there is much literature on psychogenic amnesia as dissimilar to organic amnesia, the distinction between neurological and psychological features is often difficult to discern and remains controversial. Diagnosis
Functional assessment of brain activity can be assessed for psychogenic amnesia using imaging techniques such as fMRI, PET and EEG, in accordance with clinical data. Some research has suggested that organic and psychogenic amnesia to some extent share the involvement of the same structures of the temporo-frontal region in the brain. It has been suggested that deficits in episodic memory may be attributable to dysfunction in the limbic system, while self-identity deficits have been suggested as attributable to functional changes related to the posterior parietal cortex. To reiterate however, care must be taken when attempting to define causation as only ad hoc reasoning about the aetiology of psychogenic amnesia is possible, which means cause and consequence can be infeasible to untangle. Treatments
Because psychogenic amnesia is defined by its lack of physical damage to the brain, treatment by physical methods is difficult. Nonetheless, distinguishing between organic and dissociative memory loss has been described as an essential first-step in effective treatments.
Primarily nuclear imaging techniques such as single-photon emission computed tomography (SPECT), positron emission tomography (PET), and bone scintigraphy are taken along with other data before a patient is diagnosed for Condylar Hyperplasia. In SPECT imaging, an increase uptake of the isotope is seen on the affected in comparison to the non-affected side. A difference of at least 10% or a minimum ratio of 55% to 45% uptake of technetium-99m is seen when comparing affected vs non-affected side respectively. An uptake of more than 55% and difference of at least 10% indicates an active condylar growth. Classification
Hugo Obwegesr and Makek classified condylar hyperplasia into three categories, listed in the table below. Type 1 develops its characteristics from the horizontal vector, and Type 2 develops its characteristics from the vertical vector. Type 1 CH occurs much more common (15x) than Type 2 CH. Wolford et al. in 2014, developed an updated classification of condylar hyperplasia. In 1986, Slootweg & Muller devised a histopathological classification which allows the condylar tissues to be classified into specific categories. Treatment
Many treatment options exist for this type of condition. Orthognathic surgery can be performed once the active condylar growth has finished in some cases. The point of this surgery to wait as long as the condyle is growing and only do surgery when the condyle stops growing, so the chances of any worsening of facial asymmetry lessens. This option, however, does include a person living with the facial asymmetry features all the way up until 18 to 19 years of age.