Intraoperative sonography is becoming a well-recognized addition in neurosurgery. Intraoperative sonography can be used for assistance in tumor resection, evaluation of vessels with color flow Doppler, reduction in surgery time, decreased cost, and real-time scanning without radiation administered to the patient. With technological advances occurring constantly, sonography as well as neurosurgery will continually improve. Neurosurgery is one of the most sensitive and delicate surgeries performed. Intraoperative sonography in neurosurgery can assist in tumor localization, vascular malformation detection, and anatomical evaluation of relationships between a tumor and normal brain tissue. In light of the technological advances as well as lower cost, intraoperative sonography is becoming more common in neurosurgery.

Niemann-Pick disease type C (NPC) is an autosomal, recessive lipid storage disease that can present in infants, children, and adults. Harmful quantities of lipids accumulate in the spleen, liver, lungs, bone marrow, and, in some patients, the brain. Infiltration of the lipid component can cause organs, vessels, and surrounding tissues to lose their function with advancement of the disease. The elevated levels of lipids lead to irreversible damage of the organs and organ failure, resulting in death. Sonographic evaluation of patients with NPC provides valuable information on the progression of this disease.

An arrhythmia is a disturbance in the normal rhythm of the heart. Heart rhythms are generated by the sinoatrial (SA) node and travel through the heart’s conduction system, causing the atrial and ventricular myocardium to contract and relax at a regular rate. If there is a disturbance in the electrical system of the heart, it can be detected in utero by using M-mode sonography. It is important to diagnose a fetal arrhythmia early in pregnancy. If the arrhythmia persists, it can lead to congestive heart failure and hydrops.

Testicular epidermoid cysts are benign tumors that represent only 1% of all testicular tumors. This tumor presents as a palpable mass within the testicle. High-resolution sonography can help provide a presurgical diagnosis due to the tumor’s unique sonographic appearance of a “bow tie” echogenicity. This bow tie pattern is formed by the deposition of keratin in layers by the lining of the cyst. A preoperative sonographic diagnosis of a testicular epidermoid cyst can lead to testicle-sparing surgery in healthy, young males due to the benign nature of this tumor.

Lissencephaly is a neural disorder characterized by lack of sulcations in the brain. In lissencephaly, the normal migration of the neuron does not occur due to an insult to the fetus early in gestation. This causes a “smooth brain” appearance. Lissencephaly is associated with syndromes such as Walker-Warburg and Miller-Dieker syndromes. Sonographic findings of lissencephaly include agenesis of the corpus collosum, dilated third ventricle, and lack of sulcations. Patients diagnosed with lissencephaly do not usually de-velop intellectually past the three- to five-month age level.