Progressive transcortical sensory aphasia and progressive ideational apraxia owing to temporoparietal cortical atrophy

A 65-year-old ambidextrous man with 12 years of education began to experience progressive word-finding difficulty. He had been an office worker until he retired at age 60. He had no previous medical or psychiatric problems. He was referred to our hospital for evaluation of speech difficulties 1 year after the onset of aphasia. His laboratory results were normal, and no remarkable neurological findings were noted. Neurological examination was normal with no pyramidal, extra-pyramidal nor cerebellar signs.

Neuropsychological examination (Table 1) showed remarkable word-finding difficulty but no phonological paraphasias. Grammar, articulation, prosody, and repetition were also preserved. Conversational speech was hesitant, with word-finding pauses. The maximum length of sentence repetition was five phrases. Non-word repetition was preserved. His digit span was a maximum of six digits forward and five digits backward. Comprehension of single words was nearly intact, whereas comprehension of complex sentences was impaired. For example, although he was able to comprehend simple oral sentences such as “Touch your ankle”, he was unable to comprehend complex oral sentences such as “Touch your right ankle with your left hand”. Reading of complex sentences was also impaired as was oral comprehension. His writing was severely impaired compared with his speech, suggesting that he had agraphia itself that was independent of aphasia. His calculation was also severely compromised, and he was no longer able to perform simple additions of one figure that included carrying. On neuropsychological examination, his correct naming was 25 % on the Standard Language Test of Aphasia (SLTA) [12]. Although his comprehension of single words remained 100 %, comprehension of command sentences was only 20 %. Taken together, his aphasia was categorized as transcortical sensory aphasia with preserved repetition and word meaning. Reading comprehension of complex sentence commands was only 20 %. Written naming in Kanji was 20 % and dictation of short sentences was 0 %. His correct calculation was 15 % on SLTA.

At this time, he also showed apraxia. He became unable to use nail clippers and tried to cut his nails with scissors instead. He clearly understood what the nail clippers were used for but he was not sure how to use them. No ideomotor apraxia was observed with either hand when asked to imitate the examiner’s gesture. He showed no visual agnosia or Bálint syndrome in the visual perception test for agnosia [13]. He showed no visuoconstruction disorders when copying a cube. Affect and concern with hygiene were preserved, and his personality did not change. His score on the Clinical Dementia Rating scale [14] remained at 0.5 for the initial 2 years of his illness. Brain magnetic resonance imaging demonstrated atrophy in the left temporoparietal cortices (Fig. 1a). We evaluated the patient with Tc-99 m ECD SPECT [15] (Fig. 1a), which demonstrated relative hypoperfusion mainly in the left temporoparietal areas, which partly extended to the occipital lobe. The main affected areas were slightly posterior and somewhat distant from the perisylvian area, the main area usually affected by lvPPA [2, 3]. The affected area also differed from that of svPPA in which the main affected area is typically the temporal pole [1].

At age 67, he put pesticide on a wound after he was bitten, confusing it with an antipruritic drug. On another occasion, he put denture cleaner on his garden plants. He also began to present with episodic memory deficits and tended to forget his schedule or what he had said.

His aphasia gradually worsened. At age 70, although his repetition of short sentences remained intact, he often could not understand what simple words meant. His comprehension of single words fell to 60 %, and his comprehension of command sentences became 0 % on the SLTA. His naming ability fell to 0 %. He was no longer able to read or write, including his own name and address. He was also unable to recognize tools used in everyday life. Eventually, he began to often eat non-edible objects such as sponges. He was admitted to a nursing home. The clinical features of this case most likely suggest Alzheimer’s disease.

This patient presented with transcortical sensory aphasia and ideational apraxia that insidiously worsened. Agraphia and acalculia were also observed. Episodic memory deficits became apparent 2 years after the onset of symptoms. Ideational apraxia progressed into conceptual apraxia. Hypoperfusion was found mainly in the left temporoparietal area.

A 50-year-old right-handed man with 16 years of education began to experience progressive word-finding difficulty. He had been a system engineer but began making mistakes at his work because he was unable to understand exactly what his manager told him. He had no previous medical or psychiatric problems. His older sister had been clinically diagnosed with Alzheimer’s disease at age 60. He was referred to our hospital for evaluation of cognitive function at age 52, 2 years after the onset of cognitive decline. His laboratory results were normal. Neurological examination was normal with no pyramidal, extra-pyramidal nor cerebellar signs. Neuropsychological examination (Table 1) showed word-finding difficulty but no phonological paraphasias. Grammar, articulation, prosody, and repetition were also preserved. Conversational speech was hesitant, with word-finding pauses. The maximum length of sentence repetition was six phrases. Non-word repetition was preserved. His digit span was a maximum of six digits forward and four digits backward. Comprehension of single words was intact, whereas comprehension of complex sentences was impaired. For example, although he was able to comprehend simple oral sentences such as “Touch your ankle”, he was unable to comprehend complex oral sentences such as “Touch the book on the table with the pen first, then give me the pen”. His correct naming was 65 % on the SLTA [7]. Although his comprehension of single words remained 100 %, comprehension of command sentences was 50 %. Taken together, his aphasia was categorized as transcortical sensory aphasia with preserved repetition and word meaning. He also made mistakes in writing, in particular, in Kanji, or Chinese characters. Although he was a university graduate, he could not write some Kanjis, which are taught in lower grades of primary school. Although reading was relatively preserved compared with writing, comprehension of written complex sentences was also impaired as was oral comprehension. He also showed acalculia, in particular when carrying and borrowing were needed. Reading comprehension of complex sentence commands was only 20 % on SLTA. Written naming in Kanji was 20 % and dictation of short sentences was 0 %. His correct calculation was 10 %. In addition, he was no longer able to read an analog clock. While driving, he became unsure of how to operate windshield wipers. Although he showed no visual agnosia or any signs of Bálint syndrome in the visual perception test for agnosia [13], he showed visuoconstruction disorders when copying a cube. Affect and concern with hygiene were preserved, and his personality did not change. His score on the Clinical Dementia Rating scale [14] remained at 0.5 for the initial 2 years of his illness. Brain magnetic resonance imaging demonstrated atrophy in the bilateral parietal cortices (Fig. 1b). We also evaluated the patient with Tc-99 m ECD SPECT (Fig. 1b), which demonstrated relative hypoperfusion in the bilateral temporoparietal areas, which partly extended to the occipital lobe.

At age 53, he began to complain of difficulty using electrical appliances such as vending machines and the remote control for an air conditioner. He clearly understood what these appliances are used for but was unsure how to operate them. No ideomotor apraxia was observed with either hand when asked to imitate the examiner’s gesture. He also showed dorsal simultanagnosia, one of the three sign of Bálint syndrome in the visual perception test for agnosia [13]. At age 54, he began to present with episodic memory deficits and tended to forget his schedule or what he had said. He could not copy Kanjis, nor could he even trace them. At age 55, he was no longer able to fasten his seatbelt. He showed apraxia of dressing and often put clothes on backwards or upside down. His aphasia gradually worsened.

At age 56, although his repetition of short sentences remained intact, he often could not understand what words meant. His comprehension of single words fell to 70 %, and his comprehension of command sentences became 0 % on the SLTA. His naming ability fell to 0 % on the SLTA. He became unable to flush the toilet in his house. When asked to use a comb, a toothbrush, or a fan, he was not sure how to use them, although he clearly understood what these tools are and what they are used for. He could not put his legs into his own horigotatsu, a Japanese foot warmer consisting of a short-legged table over a hole in the floor with a foot warmer and a quilt over it. He occasionally began to get lost. At age 57, he was admitted to a nursing home. The clinical features of this case most likely suggest early-onset Alzheimer’s disease.

This patient presented with transcortical sensory aphasia and ideational apraxia as well as visuospatial deficits, which gradually worsened. Episodic memory deficits became apparent 4 years after the onset of symptoms. Hypoperfusion was demonstrated mainly in the bilateral temporoparietal areas.