From the Guidelines

Yes, a computed tomography (CT) scan of the chest can identify a hiatal hernia.

A CT scan is considered the gold standard for diagnosing diaphragmatic hernias, including hiatal hernias, with a sensitivity and specificity of 14–82% and 87%, respectively 1.
The CT scan can evaluate the intrathoracic complications of herniated abdominal organs and provide detailed information about the presence, location, and size of the diaphragmatic defect.
Radiological findings on a CT scan that may indicate a hiatal hernia include diaphragmatic discontinuity, segmental non-recognition of the diaphragm, and intrathoracic herniation of abdominal contents 1.
A CT scan of the chest and abdomen is recommended when there is a persistent clinical suspicion of a hiatal hernia, despite advances in imaging methods, the chest X-ray is still useful as an initial screening tool 1.

The CT scan may miss small tears or penetrating injuries, but it is more accurate than a chest X-ray in determining the presence and size of a diaphragmatic defect 1.
The use of biological and bioabsorbable meshes in surgical repair can reduce recurrence, and laparoscopic repair is the preferred technique in hemodynamically stable patients without significant comorbidities 1.

From the Research

A CT scan of the chest can be used to identify a hiatal hernia, as mentioned in the study 2, which lists computed tomography as one of the diagnostic measures for sliding hiatal hernia.
The study 3 also suggests that identification of a hiatal hernia by computed tomography (CT) scanning is possible, particularly with axial imaging from a coronary artery calcium score exam.
Another study 4 found that high-resolution 3-dimensional tomography can be a useful tool for understanding the anatomy of hiatal hernias and surgical planning of patients eligible for laparoscopic or robotic antireflux surgery.

The study 2 compared esophageal hiatal diameters measured via ultrasonography and computed tomography, and found a statistically significant difference between patients with sliding hiatal hernias and controls.
The study 5 found that colonic distention at CT with water enema and CT colonography can induce small sliding hiatal hernias, and that the prevalence of sliding hiatal hernias in the external control group was significantly lower than in the CT-WE and CTC cohorts.
The study 4 found a correlation between tomographic and endoscopic findings for the presence and size of hiatal hernias, but no correlation between tomographic and manometric findings for the diagnosis of hiatal hernias.

The study 5 suggests that incidental findings at CT-WE and CTC should be considered according to the clinical background, and that small sliding hiatal hernias should not be reported in patients with symptoms not related to reflux disease undergoing CT-WE or CTC.
The study 3 notes that identification of a hiatal hernia by computed tomography (CT) scanning is often subjective, and that several CT features are diagnostic or suggestive of a hiatal hernia.