Jennifer Horner

Aspiration after stroke: Lesion analysis by brain MRI

Aspiration is a common problem following stroke, resulting in feeding difficulties and aspiration pneumonia. Despite past studies using clinical assessment and computed tomographic (CT) scans of the head, the correlation of stroke location with aspiration remains unclear. Since brain magnetic resonance imaging is more sensitive than CT for many stroke types, we have correlated MRI lesions with aspiration in patients who have sustained a stroke. We selected patients with acute stroke who underwent brain MRI and a swallowing evaluation. Aspiration was present in 21 of 38 patients (55%). Patients with just small vessel infarcts had a significantly lower occurrence of aspiration (3 of 14, 21%) compared to those with both large-and small-vessel infarcts (15 of 20, 75%, p=0.002). Multivariate analysis of several specific brain areas failed to identify a significant association between stroke location and the occurrence of aspiration. These findings suggest that patients who have experienced stroke should be individually evaluated for swallowing dysfunction regardless of stroke location or size, since even small-vessel strokes can be associated with aspiration in >20% of cases.

Swallowing in Alzheimer's disease

SummaryUsing a prospective case series design, we examined the incidence of oropharyngeal swallowing abnormalities in 25 patients with moderate or severe Alzheimers disease by videofluoroscopy. Aspiration occurred in 6 of 25 (28.6%). Only four patients showed unequivocally normal performance. Exploratory statistical analyses showed that swallowing abnormalities associated significantly with duration of dementia, eating dependency, and abnormal oral praxis. We observed a trend toward a higher incidence of aspiration in patients with more severe dementia. We conclude that oropharyngeal swallowing abnormalities, including aspiration, are more prevalent in patients with Alzheimers disease than in normal elderly individuals.

Restitution and substitution: Two theories of recovery with application to neurobehavioral treatment

This article reviews two theories regarding recovery from brain damage in adulthood. The notion of restitution of function assumes that behavioral improvement results from the increasing integrity of the injured functional system. In contrast, the theory of substitution of function assumes that improvement results from system reorganization or compensation. Both these processes take place during the course of neurologic recovery. The ability of the clinical neuropsychologist to maximize behavioral changes in the brain-damaged patient during the recovery period requires an appreciation for these recovery mechanisms. Treatment decisions can be enhanced by knowledge of the time course, degree of recovery potential, and behavioral constraints of these complementary recovery processes.

Progressive dysfluency associated with right hemisphere disease

A late onset progressive dysfluency following a right hemisphere stroke occurred in a 62-year-old male. Dysfluency was characterized by pronounced word and phrase reiterations, and sound and syllable reiterations to a lesser degree. Spontaneous speech was significantly more dysfluent than oral reading and repetition. Recitation and singing were minimally dysfluent. Reiterations were accompanied by reduced vocal loudness and increased rate of speech. Reiterations occurred in initial, medial, and final sentence position. Secondary symptoms such as facial grimacing were absent. In contrast to acquired cortical stuttering which is characterized by a preponderance of sound and syllable sentence initial repetitions, dysfluency was more closely characteristic of palilalia. The dysfluency occurred as a symptom of a diffuse nonspecific subcortical projection system defect related to massive infarction in the right middle cerebral artery distribution with associated atrophy.

Swallowing in Torticollis Before and After Rhizotomy

To determine risk factors for dysphagia after ventral rhizotomy, videofluoroscopic barium swallowing examinations were done on 41 spasmodic torticollis patients before and after surgery. Radiologic abnormalities were present in 68.3% of the patients before surgery, but these were only mildly abnormal in the majority. After surgery 95.1% showed radiologic abnormalities which were moderate or severe in one-third of the patients. Swallowing abnormalities correlated significantly with duration of torticollis and subjective complaints of swallowing difficulty both before and after surgery, but not with age, sex, or type of torticollis. The major acute postoperative finding was aggravation of preexisting pharyngeal dysfunction. Follow-up from about half of our original sample showed that gradual improvement occurred from 4 to 24 weeks after surgery by subjective report. We review the innervation of intrinsic and extrinsic pharyngeal musculature, and suggest that C1–3 rhizotomies and selective sectioning of the spinal accessory nerve are responsible for aggravation of pharyngeal swallowing dysfunction in the acute postsurgical period.

Evaluation of memory and language function pre- and postthalamotomy with an attempt to define those patients at risk for postoperative dysfunction

Memory and language dysfunction has been sporadically reported following stereotaxic thalamotomies. In order to determine which patients are at greatest risk and to better define the nature of this dysfunction, we have prospectively evaluated 18 patients undergoing stereotaxic thalamotomies for movement disorders (MDs). Patients were evaluated clinically, with computed tomography (CT) and with memory and language protocols (MLPs) pre- and postoperatively. Patients exhibiting postoperative deficits were again evaluated with the MLP on follow-up visits to the clinic. Significant changes in memory and language function occurred in 7 out of 18 patients. These 7 patients had diverse etiologies for their MDs. Five of the 18 patients had undergone previous thalamotomies on the contralateral side. Three of these 5 patients with bilateral thalamotomies experienced postoperative functional impairments in memory and language while only 4 of 13 patients with a unilateral thalamotomy experienced these problems. The postoperative functional impairments noted were primarily those requiring orientation and speech. All patients with postoperative memory and language impairments were again evaluated with MLPs months after the operation. In 3 of 7 patients, no improvement was noted, while the remaining 4 did recover to baseline. More severe deficits tended to occur in those patients with ventriculomegaly or evidence of other major cerebral tissue loss by preoperative CT scan and in those patients with lower MLP scores preoperatively. Postoperative memory and language dysfunction was not correlated with the number or size of the lesions made, the postoperative general neurologic examination or CT scans, or the clinical response of the MDs. From our data, it appears that patients with more profound neurologic compromise and/or bilateral involvement as evidenced by poor performance on the MLP, tissue loss on CT scanning, or previous thalamic lesion, are most at risk for memory and language dysfunction postoperatively. However, this dysfunction is not necessarily permanent. Preoperative evaluation with MLPs and CT scanning appear to be of value in predicting those patients at greatest risk for postoperative and language dysfunction.

Dysphagia in tetanus: Evaluation and outcome

A 72-year-old man who contracted tetanus after a puncture wound presented with severe dysphagia in association with trismus, risus sardonicus, and nuchal rigidity. We describe his medical course and outcome, including repeated videofluoroscopic barium swallow examinations. We emphasize the value of videofluoroscopy for examining and managing dysphagia in patients with tetanus, in both the acute and chronic stages of this rare illness.

Swallowing, speech, and brainstem auditory-evoked potentials in spasmodic torticollis

To explore the controversial “brainstem theory” of spasmodic torticollis, eight consecutively referred patients were examined. Three independent examinations were conducted on the same day: a videofluoroscopic barium swallowing examination, an instrumental speech examination, and a brainstem auditory-evoked potential (BAEP) analysis. Swallowing was normal in two patients; speech physiology, in five; and BAEPs, in all. Normal BAEPs refute the brainstem theory, while abnormalities of speech and swallowing temper this conclusion. Several alternative explanations are proposed.

Task-Dependent Neglect: Computed Tomography Size and Locus Correlations

We studied the severity and task-specific nature of neglect in relation to brain lesion size and locus in 23 right hemisphere stroke patients. We used five visuospatial tasks, including reading and writing. No single task identified hemispatial neglect in all patients. Drawing from memory was most sensitive, whereas writing was least sensitive. Neglect was not limited to parietal disease, but occurred following lesions in several cortical and subcortical locations. Severity of neglect correlated significantly with lesion locus (it was most severe with central lesions), but not with lesion size. We discuss observed patterns of neglect relative to a theory of hypoarousal and suggest the importance of neglect to prognosis for recovery from stroke.