Implantable medical devices having modular lead bores

A modular lead bore for an implantable medical device that includes medical device circuitry, the modular lead bore comprising:

• a plurality of lead bore modules that are hermetically coupled together, each lead bore module of the plurality of lead bore modules comprising a lead bore passageway and a feedthrough passageway;
• a plurality of electrical contacts, each electrical contact of the plurality of electrical contacts being aligned to the lead bore passageway of each corresponding lead bore module;
• a plurality of seals, where each seal of the plurality is present within the lead bore passageway of each corresponding lead bore module and between electrical contacts;
• a plurality of hermetic feedthrough assemblies, each hermetic feedthrough assembly of the plurality of hermetic feedthrough assemblies being present within the feedthrough passageway of each corresponding lead bore module;
• and
• a plurality of feedthrough pins, with each feedthrough pin of the plurality of feedthrough pins passing through the hermetic feedthrough assembly of each corresponding lead bore module, each feedthrough pin being electrically coupled to the electrical contact of each corresponding lead bore module and being configured to couple to the medical device circuitry.