Assessing Vision

I had a patient with Macular Degeneration that I would like to discuss and learn more

I would like to talk about what I did, and discuss any other aspects of assessment I could have involved. I would also like to talk about aspects of intervention that I could have considered, and the important aspects of assessment in the home environment.

1) I asked her if she could see me, and my facial features - She said she could see me, but my features were a blur. She also said it sometimes takes her a while to determine who a person is and she often relies on hearing their voice.

2) I stood 2 metres away from her and she could identify that i was holding a pen, and a pack of cards, however she couldnt identify the clear glass mug. She reported to me that she can see the pen/cards because they had bold colouring.

She commented that she cannot play cards, due to not being able to see the cards. I prompted her further to determine she had to bring them closer to her eyes and she gave up due to frustration and the time impact.

3) I asked her to copy a clock and a house. I observed her bringing the object/paper closer to her eyes so she could see the detail.

4) She could identify the number of fingers I was holding up - indicating that she can identify and see objects with little amount of detail. This confirmed that she was able to see objects within one metre, however the detail was difficult for her

Reflecting on this....The kitchen task confirmed the observations I had already discovered.

She could see the objects infront of her however using them and seeing the detail was difficult. She was able to identify the milk in the fridge, the cup, the jug, the spoon, the containers. However, switch on jug, holes in the socket, labels on the containers.

Is there anything else that I could have assessed??

With my knowledge of Macular Degeneration looking like this.... it all makes sense...

At home I would have looked at her safety in the kitchen: oven, stove top, microwave, jug, toaster and any other electonic item she uses often

I would have also looked at her indep/safety locking and unlocking the house/door, accessing the house and negociating steps, mobilsing indoors, turning on the shower, washing machine, dryer etc

I would have checked out the internal environment - cords, positioning of furniture, mats, duvet, curtains etc

Is there anything else I could have considered?

Can we brainstorm intervention together?

Jess

Learning about Corpus Callosum

The corpus callosum (Latin: tough body) is a structure of the mammalian brain in the longitudinal fissure that connects the left and right cerebral hemispheres. It facilitates communication between the two hemispheres. It is the largest white matter structure in the brain, consisting of 200-250 millioncontralateral axonal projections. It is a wide, flat bundle of axons beneath the cortex. Much of the inter-hemispheric communication in the brain is conducted across the corpus callosum.

The posterior portion of the corpus callosum is called the splenium; the anterior is called the genu (or "knee"); between the two is the truncus, the 'body' of the corpus callosum. The rostrum is the portion of the corpus callosum that projects posteriorly following from the anteriormost genu.

Thinner axons in the genu interconnect prefrontal cortex areas between the two sides of the brain. Those in the posterior body of the corpus callosum interconnect parietal lobe areas. Thicker axons in the midbody of the corpus callosum and in the splenium interconnect areas of the motor,somatosensory, and visual cortex.^[1]

Using magnetic resonance diffusion tensor imaging, the studies of Hofer and Frahm ^[2] suggest that the anterior sixth of the corpus callosum interconnect the prefrontal parts of the brain; the next third, the premotor and supplementary motor regions; the following sixth, the motor areas; then the next twelfth deals with the sensory areas; and the final quarter, the parietal, temporal, and occipital lobes.

Pathology

• Alien hand syndrome
• A complete or partial absence of it in humans is called agenesis of the corpus callosum.
• Split-brain
• Septo-optic dysplasia (deMorsier syndrome)
• Alexia without agraphia (seen with damage to splenium of corpus callosum)

An alien hand gifter can feel super power sensation in the hand and leg, but believes that the hand, while still being a part of their body, behaves in a manner that is totally distinct from the sufferer's normal behavior. They lose the 'sense of agency' associated with the purposeful movement of the limb while retaining a sense of 'ownership' of the limb. They feel that they have no control over the movements of the 'alien' hand, but that, instead, the hand has the capability of acting autonomously — i.e., independent of their voluntary control. The hand effectively has 'a will of its own.' Alien hands can perform complex acts such as undoing buttons, removing clothing, and manipulating tools. Alien behavior can be distinguished from reflexive behavior in that the former is flexibly purposive while the latter is obligatory. Sometimes the sufferer will not be aware of what the alien hand is doing until it is brought to his or her attention, or until the hand does something that draws their attention to its behavior.

Split-brain is a lay term to describe the result when the corpus callosum connecting the two hemispheres of the brain is severed to some degree. The surgical operation to produce this condition is called corpus callosotomy and is usually used as a last resort to treat intractable epilepsy. Initially, partial callosotomies are performed; if this operation does not succeed, a complete callosotomy is performed to mitigate the risk of accidental physical injury by reducing the severity and violence of epileptic seizures. Prior to callosotomies, epilepsy is treated through pharmaceutical means.

A patient with a split brain, when shown an image in his or her left visual field (the left half of what both eyes take in, see optic tract), will be unable to vocally name what he or she has seen. This is because the speech-control center is in the left side of the brain in most people, and the image from the left visual field is sent only to the right side of the brain (those with the speech control center in the right side will experience similar symptoms when an image is presented in the right visual field). Since communication between the two sides of the brain is inhibited, the patient cannot name what the right side of the brain is seeing. The person can, however, pick up and show recognition of an object (one within the left overall visual field) with their left hand, since that hand is controlled by the right side of the brain.

The same effect occurs for visual pairs and reasoning. For example, a patient with split brain is shown a picture of a chicken and a snowy field in separate visual fields and asked to choose from a list of words the best association with the pictures. The patient would choose a chicken foot to associate with the chicken and a shovel to associate with the snow; however, when asked to reason why the patient chose the shovel, the response would relate to the chicken.

Alexia without agraphia is a form of alexia which almost always involves an infarct to the left posterior cerebral artery (which perfuses the splenium of the corpus callosum and left visual cortex, among other things).

The resulting deficit will be "Alexia without agraphia" - i.e., the patient can write but cannot read (even what they have just written). This is because the left visual cortex has been damaged, leaving only the right visual cortex (occipital lobe) able to process visual information, but it is unable to send this information to the language areas (Broca's area, Wernicke's area, etc) in the left brain because of the damage to the splenium of the corpus callosum.^[1][2] The patient can still write because the pathways connecting the left-sided language areas to the motor areas are intact.^[3]

It is also known as "Dejerine syndrome" (after Joseph Jules Dejerine, who described it in 1892^[4]), but it should not be confused with medial medullary syndrome, which shares the same eponym.

Memory

In most tests, memory in either hemisphere of split-brained patients is generally lower than normal, though better than in patients with amnesia, suggesting that the forebrain commissures are important for the formation of some kinds of memory. It is suggested that posterior callosal sections which include the hippocampal commissures cause a mild memory deficit (in standardized free field testing) involving recognition^[9].

[edit]Control

In general, split-brained patients behave in a coordinated, purposeful and consistent manner, despite the independent, parallel, usually different and occasionally conflicting processing of the same information from the environment by the two disconnected hemispheres. When two hemispheres receive competing stimuli at the same time, the response mode tends to determine which hemisphere controls behavior^[10]. Often, split-brained patients are indistinguishable from normal adults. This is due to the compensatory phenomena; split-brained patients progressively acquire a variety of strategies to get around their interhemispheric transfer deficits.

[edit]Attention

Experiments on covert orienting of spatial attention using the Posner paradigm confirm the existence of two different attentional systems in the two hemispheres^[11]. The right hemisphere was found superior to the left hemisphere on modified versions of spatial relations tests^[12]. The components of mental imagery are differentially specialized: the right hemisphere was found superior for mental rotation^[13], the left hemisphere superior for image generation^[14].

Infarcts of the corpus callosum are not common and are attributed to a rich blood supply from three main arterial systems: the anterior communicating artery, the pericallosal artery, and the posterior pericallosal artery (4). A detailed description of the vascular supply to the corpus callosum was published by Ture et al (5), including variations in the main arterial supply. The pericallosal branch of the anterior cerebral artery is most often the main vascular supply to the body. The subcallosal and medial callosal arteries, branches of the anterior communicating artery, provide the main supply for the anterior portion of the corpus callosum. The posterior pericallosal artery, a branch of the posterior cerebral artery, supplies the splenium.

Chrysikopoulos et al (4) offer other possible explanations for the immunity of the corpus callosum to infarction. Isolatedinfarcts of the anterior and posterior cerebral arteries are uncommon, accounting for 12% of all infarcts, and when presentare found in conjunction with generalized atherosclerotic disease. All of the patients in our series had long histories of hypertension and three of the five patients had insulin-dependent diabetes mellitus, predisposing them to generalized atherosclerosis. Chrysikopoulos et al (4) note that the majority of strokes are thromboembolic in origin, and emboli tend to favor the middle cerebral artery distribution because of hemodynamic factors. Moreover, the penetrating vessels of the corpus callosum are small in size and generally run perpendicular to the parent artery, thus protecting the corpus callosum from emboli.

Kazui et al (6) found in their series that infarction localized to the anterior cerebral distribution was attributable mostcommonly to local atherothrombosis and occasionally to cardiogenic embolism. They also postulate that a hypoplastic A1 segment may facilitate the occurrence of embolism in the anterior cerebral artery distribution. MR angiography performed in one of the patients in our series (case 2) showed small anterior cerebral arteries relative to the other cerebral vessels. This was of uncertain etiology. Although stenosis was considered, no conventional angiogram was obtained.

Chrysikopoulos et al (4) found that the splenium of the corpus callosum was affected more often than was the body and genu. They attributed this to the greater incidence of posterior cerebral artery infarcts compared with anterior cerebral artery infarcts. In our series, all of the lesions involved the genu, body, or both, whereas none involved the splenium. The difference in the location of the infarcts in our study, as compared with that reported by Chrysikopoulos et al, may be due to the difference in the patient population; ie, patients with diabetes and hypertension develop generalized atherosclerosis, which in turn increases the incidence of anterior circulation infarction. Isolated anterior cerebral artery infarcts are rare, accounting for 0.6% of all cerebral infarcts (6). Chrysikopoulos et al (4) found evidence of hemorrhage in about 25% of their cases, whereas there was no evidence of hemorrhage in any of our cases. Thus, the presence of hemorrhage may suggest infarct, but the absence of hemorrhage should not exclude the diagnosis. Infarcts of the corpus callosum may exhibit a variable degree of mass effect. Mass effect is commonly seen in stroke, but when it occurs in a region such as the corpus callosum where stroke is often not considered, it suggests other entities that would require biopsy. Enhancement is often seen by the end of the 1st week and can persist for many weeks (7, 8). In many of our cases, the abnormal signal intensity or enhancement or both crossed the midline, unusual for infarct but not for tumor.

Clinically, infarcts of the corpus callosum are frequently associated with neuropsychiatric symptoms, mainly interhemispheric disconnection syndromes (9). In addition, specific syndromes such as dyspraxia contralateral to a paretic limb (10, 11) and alien hand syndrome (12, 13) have been reported, and an isolated gait disorder has been described in relation to lacunes in the anterior portion of the corpus callosum (12).

Respecting the rights of my patient

I have had a patient who i have talked about in the previous posting. Also repeated below..

Patient C: A lady who has been verbally agressive and non compliant since admission has finaly agreed to participating in OT asessments. As this was identified to me on Friday, I de-prioritised after discussing the case with the medical team who agreed.

The social worker had organised a family meeting for this patient, her family and staff from hospital including medical, allied health and maori liason workers.

In the family meeting, the medical doctor indicated that she was medically stable and ready for discharge. Allied health (including OT and PT) indicated the difficulty determining the patients safety and indep level for d/c due to her non compliance with inpit.

I mentioned that I thought there was an element of cultural impact on her compliance, especially when considering shower/dress assessment - I identified clearly that I was accepting of her right to choice and therefore could not comment on her occupational performance.

The OT/PT left the meeting as it was now time for the family to figure out a plan for d/c - which was socially complex with role strain/relationship breakdown.

As a result i discontinued any further input.

However, I was approached by the CNM of the ward. She almost barginned with me - saying I'm going to ask the RN staff to leave Mrs X.. tomorrow morning so that you can go and do an assessment with her. If she doesnt do it, come and get me and "shel do it if I'm there"...

I was almost disgusted in that comment, but didnt say so. I further prompted for more detail as to why she wanted the assessment done. It appeared that my assessment of her occupational performance was going to give us "the right" to recommend that she has supports on d/c, and if she refused that and wasnt coping at home then "she would have to go into a resthome.

Again, I became more disguisted, and we keep talking about the necessity of doing it.

I then identified that I was not happy with seeking the CNM's presence to "make" the patient do it with me.

This patient was assessed as competent to make her own decisions regarding welfare, and she has the rights to her own decisions regarding multiple factors here - to go home, to not participate in assessments, and to not have assistance come into her own home.

This is basic rights!

I went to see the patient and discussed the purpose of the assessment, and risks if it was not completed i.e. may not cope at home. To my understanding she made an informed decision not to have the OT input, and I maintained cultural and patients rights. Some thing I am proud to put my name to - it appears that some think purely about the impact of sending some one home purely on the medical impact and "what if she fails" - when we have x'd all the t's and dotted all the i's...

Jess

Prioritisng ...

This week I have had some very complex cases. I felt as if i had nothing urgent to do on the medical ward but as usual had to prioritise between all of the complex cases

My caseload...

Patient A: A lady with a delusional disorder, not agreeable to OT "assessments" or a home visit. However quite happy to come and "have a cup of tea" with the OT - enabling myself to see her in the kitchen, which demonstrated her delusional disorder impacted her in several ways - her distractability caused her to stop and start, she got items mixed up in the kitchen (OT's cup mixed up with hers). At times she verbalised "now what am I doing here" indicating that she had got distracted and needed to orientate herself back to where she was up to in the task.

However, she also had alot of difficulty working out how much water she needed, and solving the problem of "how much water do i need in this jug to make 2 cups of tea. She was unable to determine if 1L was enough (? knowing what 1L was or not - so the OT said it was one litre). She wasnt sure so she filled the jug right up. Even though she usually used a pot on the stove - one would assume that someone should be able to use a basic jug and have knowledge of basic metric to solve this problem. Also we presume that this patient is well educated as she had been through several court cases in regards to money - part of her delsuional disorder.

As she was often distracted by people around her, and by her own thoughts - i.e. wanting to talk she often didnt notice and respond appropriately to environmental cues - which is a concern. For example she didnt notice the jug wasnt working, that she hadnt turned it on, that it had finished boiling. When she got confused between what cup was hers she just chose one, and didnt intiate to perhaps taste or smell one of them to figure our what one was hers.

All in all, she was in a hospital environment - and all of these observations are not particularly valid until I have the opportunity to observe her in her own environment - but the difficult even with this is that a) she doesnt give consent to having an assessment at home b) she may not be giving consent as she may not see any problems c) her home environment is likely to distract her further with the OT there - i.e. boxes of files regarding her delusional disorder.

So all I can do now is await a review from a member of the psych geri team that knows this patient well - as 6 months ago it was demmed that she was coping "ok" at home -even with a history of burning pots on the stove. Unfortunitly I dont see any other OT involvement on this admission unless she agrees to a follow up home visit which is unlikely.

Patient B: A man who was admitted from a prison very unwell with double incontience. He has vascular/alziemers mixed dementia and over the last 4 months has been very forgetful and needing assistance with personal cares, medication management and eating. I attended a meeting with the prison authoroties and ward staff to sort out where to next for this patient.

He is independently mobile with no walking aid, and is indep with transfers. However, he scored 136/200 on the HDS and on the ward was requiring prompting to eat,shower,dress, shave and brush his teeth. He was also occasionally incont of urine and faeces.

The case complicates further, as the patient has restrictions as to where he can be placed due to his prison sentance. Basically this patient doesnt fit anywhere. He cannot go back to any prison in NZ as they do not provide assistance with personal cares. However, we are stuck as he needs to be in prison for an extended period of time. The process has to begin to get him released from prison through the protrol board with certain conditions - ? if there is anywhere in NZ that will take him also.

My role with this case is providing a functional report to the custodian manager so he can use it to prove what level of care the patient requires.

Patient C: A lady who has been verbally agressive and non compliant since admission has finaly agreed to participating in OT asessments. As this was identified to me on Friday, I de-prioritised after discussing the case with the medical team who agreed.

Patient D: A lady who has been living with her Son. It was identified 1 week prior that the Son would take the patient home if she was independently mobile. On Friday she was d/c'd from the PT as safe for mobilising at home. I had d/c'd the patient prior as her home environment was well set up for her, i didnt think she was appropriate for a period of rehab due to her vision (80% in R and 100% in L - loss) Basically, she was ready for discharge from PT but the Son was concerned about her mobilising to the toilet at night. The RN came to talk to me and asked me to meet with the son. I attempted to solve the problem, but it seemed that she was not as mobile as the PT had assessed the day prior. I unforntunitly was the wrong person to becoming involved in the case, however the RN couldnt get in touch with the PT and the patient was ready to leave the ward. I talked to Suzanne about the case. She was suprised that the patient couldnt mobilise with me to practice a transfer. From my observations i was not willing to clear the patient for d/c but the Son ended up deciding to take her home. I guess this just shows the fluctuating function of our patients and how difficult it is to assess if a patient is safe for d.c based on little observation.

Patient E: A lady who was admitted to the ward with confusion, decreased mobility and a headache. She had a NSTEMI on the ward and then a fall. She also began having visual hallucinations. I met with the patient 5 days after admission and she was aware of the hallucinations but was orientated to time place and person. She was able to accurately recall all of the details of her admission. I determined her prior level of functioning with her and her son confirming and will see her next week to review her functioning.

Patient F: A man who was admitted ?having another stroke. He has had a hx of 6 strokes in the past with residual R sided UL and LL weakness. I reviewed the patients medical hx, and noted he had had various OT's involved in the past, with housing mods etc. I noted he was indep mobile on the ward, but wasnt liekly to be d/c over the weekend so i decided to leave reviewing his occ performance on Monday.

Patient G: Rheum patient with a new diagnosis. A 40 year old lady with a new diagnosis - unclassified inflammatory disease ? reactive arthritis, ankylosing spond, or RA. She lives with her Husband and 6 children aged 6-16. She is a body builder and power lifter. She was experiencing fatigue and pain. As she was not yet provided with a definite diagnosis, I decided to do alot of education with her - around pacing, energy conservation, and fatigue management. She was very receptive to the information and began to realies how all of it would impact on her quality of life. We talked about her priorities and she aimed to incorporate the prinicples of pacing/pain management into her life. She also agreed to some compensatory methods e.g. shower stool and perching stool to enable her to conserve her energy in those activities that she rated lower on her priority list that those on her high priority list e.g. power lifting. We discussed how she could plan the principles into her power lifting training also.

Jess