Mild trigonocephaly with clinical symptoms: analysis of surgical results in 65 patients.

Introduction: It has been believed that isolated, mild trigonocephaly rarely presents with clinical symptoms.

Patients And Methods: We diagnosed and operated on 65 patients with mild trigonocephaly and developmental delay up to July 2000. There were 47 boys and 18 girls in our series. All patients had symptoms such as delay in language development, hyperactivity, autistic tendencies, and motor dysfunctions. Their facial features were characterized by a metopic ridge, depressed temples, heel-shaped rather than keel-shaped forehead, and slight hypotelorism. The most important physical sign was the palpable metopic ridge. Most patients did not exhibit any symptoms until they were more than 1 year old. Fifteen patients showed regression in language acquisition and use. Three-dimensional computed tomography revealed the metopic ridge, depressed pterional regions, hypotelorism, and small anterior fossae. Magnetic resonance imaging was performed on all patients and demonstrated no abnormal findings in the brain. Single-photon emission computed tomography (SPECT) was performed on 83% of patients and revealed decreased cerebral blood flow (CBF) in the frontal lobes of 76% of those patients. Decompressive cranioplasty of the frontal bone involving the skull base was performed on all patients.

Results: In most (61 out of 65) patients a degree of postoperative improvement in clinical symptoms was noted, especially in behavioral problems. Postoperative SPECT demonstrated increased CBF in the frontal lobes in 95% of the patients.

Conclusion: Based on these results, it can be postulated that mild trigonocephaly is frequently associated with developmental delays and that these symptoms can be improved to a certain degree by decompressive cranioplasty.