Michael L. Rosenberg

Psychiatric disorders and functional impairment in patients with persistent dizziness

Objective: To determine the prevalence and predictors of psychiatric dizziness and to measure functional impairment associated with dizziness.Design: Consecutive outpatients with a chief complaint of dizziness.Setting: Four outpatient clinics at a military teaching hospital.Patients: 100 dizzy patients and 25 control patients.Measurements and main results: Structured psychiatric interviews were conducted using the Diagnostic Interview Schedule, and functional status was assessed with the Sickness Impact Profile and the 20-item MOS (Medical Outcomes Study) Short-Form. Psychiatric disorders were a primary or contributory cause of dizziness for 40% of the dizzy patients. Compared with the control patients, the dizzy patients had a higher lifetime (46% vs 32%) as well as recent (37% vs 20%) prevalence of axis I disorders. The greatest differences were in disorders of depression and somatization. The dizzy patients had a higher lifetime prevalence (2 3% vs 8%) as well as recent history (11 % vs 0%) of major depression or dysthymia. Also, somatization disorders were strikingly more common among the dizzy patients than among the control patients (37% vs 8%, p=0.005), with the dizzy patients reporting more than three times as many psychiatric or unexplained physical symptoms (5.2 vs 1.5). Age <40 years, related complaints of weakness or headaches, and dizziness provoked by hyperventilation or standing were independent predictors of psychiatric dizziness. The dizzy patients reported moderate functional impairment, which was most severe among those with psychiatric disorders.Conclusions: Persistent dizziness is associated with increased functional impairment and psychiatric comorbidity, particularly depression and somatization. Moreover, psychiatric disorders aggravate the impairment that occurs with dizziness alone.

Unilateral pursuit-induced congenital nystagmus

We describe two patients with a lifelong history of oscillopsia only when following objects moving toward their left side. Neurologic examination was normal except for eye movements. The patients showed nystagmus during any tasks that required visual following toward the left (ie, smooth pursuit, optokinetic nystagmus, and vestibulo-ocular-reflex-suppression), but had no nystagmus during fixation of stationary targets or visual following tasks to the right. Eye-movement recordings showed waveforms during pursuit to the left that were typical of congenital nystagmus.

One-year outcome for patients with a chief complaint of dizziness.

Objective: To determine the one-year outcome for patients with a chief complaint of dizziness that had persisted at least two weeks.Design: Prospective cohort study.Setting: Federal teaching hospital.Patients: 100 dizzy patients and 25 control subjects.Measurements: The primary outcome was dizziness status (improved or not improved); the secondary outcomes were morbidity and health care utilization.Results: The dizziness resolved for 18 patients, whereas the status improved for 37, stayed the same for 32, and worsened for 11, with two patients lost to follow-up. Thus, 55% of patients whose dizziness had not resolved two weeks after their initial visits improved over the subsequent 12 months. Logistic regression revealed four independent predictors of persistent dizziness at one-year follow-up: dizziness due to psychiatric causes, dysequilibrium, vertigo other than benign positional vertigo, vestibular neuronitis, or migraine (odds ratio, 6.3; 95% CI, 2.1–18.6); daily dizziness (odds ratio, 6.4; 95% CI, 2.0–21.0); dizziness worse with walking (odds ratio, 3.0; 95% CI, 1.1–9.0); and patient had initially feared a serious illness (odds ratio, 0.25; 95% CI, 0.10–0.74). These four factors could be used to classify patients as having either a high (82%), medium (47%), or low (0%) likelihood of improvement at one-year follow-up. One patient died from heart failure, and none developed a serious disease for which dizziness had been a harbinger. Dizziness was not associated with an increased number of clinic visits.Conclusions: Among patients with a chief complaint of dizziness who are still symptomatic at two-week follow-up, more than half improve within a year. Clinical factors identify patients at higher risk for persistent dizziness.

Gaze-evoked visual seizures in nonketotic hyperglycemia

Summary: Focal motor seizures are commonly a symptom of nonketotic hyperglycemia (NKH). Posture‐induced motor seizures are less common but have been reported in some patients with this disorder. We report the first case of gaze‐evoked sensory (visual) seizures in nonketotic hyperglycemia. Both seizures and ictal ÉEG findings disappeared shortly after hyperglycemia was corrected.

Nystagmus and visual evoked potentials

The pattern reversal evoked potentials test (PR-VEP) is widely used for assessing the integrity of the anterior visual pathways. With the conventional black and white check stimulus, a successful test requires that the patient be able to fixate at the center of the screen. Although in most patients with nystagmus a reliable VEP can be obtained, we have noted that some patients may have no response even in the absence of anterior visual pathway dysfunction. We suspected that this was due to a decrease in foveation of each check, secondary to the nystagmus. To test this hypothesis we evaluated 4 patients with marked horizontal nystagmus and found no evidence of anterior visual pathway dysfunction. The conventional PR-VEP showed absence of P100 response bilaterally in all patients. With horizontal grating stimulus, two patients demonstrated well defined P100 responses bilaterally and in the other two, a unilateral response was noted. The latency and amplitude of all of these responses was normal. A study of ...

Miosis and internal ophthalmoplegia as a manifestation of partial seizures

We present a patient whose only physical manifestation of a partial sensory seizure was bilateral pupillary constriction and internal ophthalmoplegia. The onset and offset of each attack corresponded distinctly with an electroen‐cephalographic discharge of the left temporo‐occipital region. We propose involvement of a cortical pupillary constrictive center in the temporal‐occipital area. NEUROLOGY 1991;41:737‐739

The Friction Sweat Test as a New Method for Detecting Facial Anhidrosis in Patients With Horner's Syndrome

Forty-eight patients with Horners syndrome documented by cocaine test were examined with the friction sweat test, a method of detecting a mild sweating asymmetry using alcohol and a standard office prism bar. In all but one patient, the results of the friction test corresponded with the results predicted by the history, physical examination, and Paredrine testing, or with the results of a starch-iodine sweat test. The test is a quick, simple, and reproducible procedure that allows a more accurate determination of the location of the Horners syndrome at the initial office visit, and therefore assists in determining what tests need to be performed in the further examination of the patient.

Physiologic Anisocoria: A Manifestation of a Physiologic Sympathetic Asymmetry

Forty-two consecutive subjects identified clinically by other clinicians as having anisocoria were evaluated by the author in a blinded fashion with the friction sweat test. The presence and side of any ptosis or lid fissure narrowing was also noted. Thirty-three of 42 (79%) had an associated decrease in sweating on the same side as the smaller pupil. Three (7%) had decreased sweating contralateral to the miosis and in 6 (14%) no significant asymmetry could be detected. Fifteen had an associated ptosis and narrowed lid fissure, all but one ipsilateral to the miosis. These findings strongly suggest that physiologic anisocoria is a manifestation of a physiologic asymmetry of resting sympathetic tone.

Stimulus Sensitive Constant Micro Macro Square-Wave Jerks in a Comatose Patient

Abstract Saccades are generally thought of as being cortically generated and not seen in comatose patients. We describe a patient, comatose secondary to a large intracerebral hemorrhage, who developed constant rhythmic small amplitude square-wave jerks with an intersaccadic interval of 130 ms. Despite the patient’s comatose state the eye movements would stop transiently in response to auditory or tactile stimulation and then quickly regain their previous amplitude. The case suggests that the presence of repetitive saccades in the form of square-wave jerks does not indicate consciousness.

Failure of the Clinical Examination to Predict the Presence of Functional Vision

The absence of a pupillary light reflex and the lack of any clinical response to visual stimulation are generally considered reliable signs of poor visual function in patients with abnormal mental status. Two case reports are presented, one with no pupillary light reflex and no response to visual stimuli; and another with no clinical response to visual stimulation. After several months with no signs of vision, both patients regained significant visual function. It is important to recognize that all signs of visual function can be absent despite the potential for good vision. This should be considered before concluding that visual loss will be permanent.