Hippocampal Volume in Schizophrenia and Its Relationship with Risperidone Treatment: A Stereological Study

Abstract

The purpose of this study was to assess the significance of the hippocampal volume differences and its relation with risperidone treatment in schizophrenia. In schizophrenic patients who were on risperidone treatment (n = 11) and in healthy volunteers (n = 11), volumes of the hippocampi were estimated using magnetic resonance images (MRIs). A detailed systematic series of coronal MRIs of the entire brain (3 mm thickness, T₁-weighted, TR/TE 400/10 ms) was obtained for each subject. All estimations were done according to Cavalieri’s method by a modified point-counting grid placed on surface areas of hippocampal slices. The mean right and left hippocampal volumes in schizophrenics and control subjects were 1,059.4 and 1,003.2 mm³, and 1,780.1 and 1,589.1 mm³, respectively. The corresponding coefficients of errors were 0.05 and 0.068, and 0.059 and 0.081, respectively. The volumes of left and right hemispheres were not significantly different in both schizophrenic patients and controls (p > 0.05). However, a statistically significant difference (p < 0.05) was found between hippocampal volumes of the schizophrenic patients and controls. In conclusion, the hippocampal volume of the schizophrenic patients is significantly smaller than of the healthy controls. The patients who responded well to risperidone treatment had significantly greater hippocampal volumes than the patients who did not respond properly. Thus, hippocampal volume may be a predictor of the treatment response of schizophrenics to risperidone.

Magnetic Resonance Imaging Predictors of Treatment Response in First-Episode Schizophrenia

“…6 Similarly, Zipursky et al 7 reported that cortical gray matter deficit predicted the need for dose escalation due to poor clinical response. In contrast, other work indicates that patients who responded to antipsychotics had larger hippocampal 8 and frontal 10 volumes compared with patients who did not respond and that partially responsive patients with larger brain volumes may be more likely to experience the benefits of clozapine treatment. 9 Our data converge with prior studies suggesting that patients with schizophrenia most likely to derive clinical benefit from antipsychotic medications have greater gray matter thickness compared with nonresponders and healthy volunteers.…”

“…[17][18][19] The goal of this study was to identify MR imaging predictors of treatment response in patients experiencing a first-episode of schizophrenia using cortical pattern matching to quantify gray matter thickness and cortical asymmetry. Based on prior work suggesting that cortical gray matter deficits predicted antipsychotic dose escalation and that antipsychotic response was associated with larger brain volume, 8,9 we predicted that greater gray matter thickness would be associated with response to antipsychotic medications. In addition, based on our prior work indicating that abnormal cerebral ''torque'' was associated with worse functional outcome in schizophrenia, 12 we further predicted that greater hemispheric shape asymmetry would be associated with antipsychotic response.…”

MR-based in vivo hippocampal volumetrics: 2. Findings in neuropsychiatric disorders

“…Smaller bilateral hippocampi in schizophrenia have been found by a large number of research groups. [233][234][235][236][237][238][239][240][241][242][243][244][245][246][247] This reduction in volume is related to symptom severity. 248 Some studies were only able to find evidence for significantly smaller left hippocampal volume.…”

Numerical analysis of age and gender-dependent neuronal cells in postnatal development of rat hippocampus

“…To date there have been numerous novel studies using various research techniques and reporting a wealth of information about different aspects of the hippocampus. In particular, developmental properties 3,4 , response to lesion or damage 5 relationship with other diseases 6,7 , contribution to learning and memory 8 , neurotoxic effects of some agents 9 , sex differences, including right-left asymmetry aspects 10 , and the generation of new neuronal cells known as neurogenesis [11][12][13] .…”